Reflow Makefile.
Sort using scripts/sort-makefile-lines.py.
No code generation changes observed in binary artifacts.
No regressions on x86_64 and i686.
Linux 6.3 has no new syscalls. Update the version number in
syscall-names.list to reflect that it is still current for 6.3.
Tested with build-many-glibcs.py.
While mach/kern_return.h happens to pull mach/machine/kern_return.h,
mach/machine/boolean.h, and mach/machine/vm_types.h (and realpath-ing them
exposes the machine-specific machine symlink content), those headers do not
actually define anything machine-specific for the content of errno.h.
So we can just rule out these machine-specific from the dependency
comment.
We already did the same change for Hurd
(https://git.savannah.gnu.org/cgit/hurd/hurd.git/commit/?id=ef5924402864ef049f40a39e73967628583bc1a4)
Due to MiG requiring the subsystem to be defined early in order to know the
size of a port, this was causing a division by zero error during ./configure.
We could have just move subsystem to the top of the snippet, however it is
simpler to just remove the check given that we have no plans to use some other
MiG anyway.
HAVE_MIG_RETCODE is removed completely since this will be a no-op either
way (compiling against old Hurd headers will work the same, new Hurd
headers will result in the same stubs since retcode is a no-op).
Message-Id: <ZFspor91aoMwbh9T@jupiter.tail36e24.ts.net>
This patch redirects the error functions to the appropriate
longdouble variants which enables the compiler to optimize
for the abi ieeelongdouble.
Signed-off-by: Sachin Monga <smonga@linux.ibm.com>
Reflow all long lines adding comment terminators.
Sort all reflowed text using scripts/sort-makefile-lines.py.
No code generation changes observed in binary artifacts.
No regressions on x86_64 and i686.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Summary of changes:
- Use BAD_TYPECHECK to perform type checking in a cleaner way.
BAD_TYPECHECK is moved into sysdeps/mach/rpc.h to avoid duplication.
- Remove assertions for mach_msg_type_t since those won't work for
x86_64.
- Update message structs to use mach_msg_type_t directly.
- Use designated initializers.
Message-Id: <ZFa+roan3ioo0ONM@jupiter.tail36e24.ts.net>
Summary of the changes:
- Update msg_align to use ALIGN_UP like we have done in previous
patches. Use it below whenever necessary to avoid repeating the same
alignment logic.
- Define BAD_TYPECHECK to make it easier to do type checking in a few
places below.
- Update io2mach_type to use designated initializers.
- Make RetCodeType use mach_msg_type_t. mach_msg_type_t is 8 byte for
x86_64, so this make it portable.
- Also call msg_align for _IOT_COUNT2/_IOT_TYPE2 since it is more
correct.
Message-Id: <ZFMvVsuFKwIy2dUS@jupiter.tail36e24.ts.net>
arm_sve.h depends on stdint.h but that relies on libc headers unless
compiled in freestanding mode. Without this change a bootstrap glibc
build (that uses a compiler without installed libc headers) failed with
checking for availability of SVE ACLE... In file included from [...]/arm_sve.h:28,
from conftest.c:1:
[...]/stdint.h:9:16: fatal error: stdint.h: No such file or directory
9 | # include_next <stdint.h>
| ^~~~~~~~~~
compilation terminated.
configure: error: mathvec is enabled but compiler does not have SVE ACLE. [...]
This patch enables libmvec on AArch64. The proposed change is mainly
implementing build infrastructure to add the new routines to ABI,
tests and benchmarks. I have demonstrated how this all fits together
by adding implementations for vector cos, in both single and double
precision, targeting both Advanced SIMD and SVE.
The implementations of the routines themselves are just loops over the
scalar routine from libm for now, as we are more concerned with
getting the plumbing right at this point. We plan to contribute vector
routines from the Arm Optimized Routines repo that are compliant with
requirements described in the libmvec wiki.
Building libmvec requires minimum GCC 10 for SVE ACLE. To avoid raising
the minimum GCC by such a big jump, we allow users to disable libmvec
if their compiler is too old.
Note that at this point users have to manually call the vector math
functions. This seems to be acceptable to some downstream users.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
dev_t are 64bit on Linux ports, so better increase their size on 64bit
Hurd. It happens that this helps with BZ 23084 there: st_dev has type fsid_t
(quad) and is specified by POSIX to have type dev_t. Making dev_t 64bit
makes these match.
The standards want msg_lspid/msg_lrpid/shm_cpid/shm_lpid to be pid_t, see BZ
23083 and 23085.
We can leave them __rpc_pid_t on i386 for ABI compatibility, but avoid
hitting the issue on 64bit.
The standards want uid/cuid to be uid_t, gid/cgid to be gid_t and mode to be
mode_t, see BZ 23082.
We can leave them short ints on i386 for ABI compatibility, but avoid
hitting the issue on 64bit.
bits/ipc.h ends up being exactly the same in sysdeps/gnu/ and
sysdeps/unix/sysv/linux/, so remove the latter.
The standards want l_type and l_whence to be short ints, see BZ 23081.
We can leave them ints on i386 for ABI compatibility, but avoid hitting the
issue on 64bit.
These were created by creating stub files, running 'make update-abi',
and reviewing the results.
Also, set baseline ABI to GLIBC_2.38, the (upcoming) first glibc
release to first have x86_64-gnu support.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
If we're trying to interrupt an interruptible RPC, but the server fails
to respond to our __interrupt_operation () call, we instead destroy the
reply port we were expecting the reply to the RPC on.
Instead of deallocating the name completely, replace it with a dead
name, so the name won't get reused for some other right, and deallocate
it in _hurd_intr_rpc_mach_msg once we return from the signal handler.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230429201822.2605207-4-bugaevc@gmail.com>
We make lib{mach,hurd}user.so only call __mig_strlen which can be
relocated before libc.so is relocated, similar to what is done with
__mig_memcpy.
Message-Id: <ZE8DTRDpY2hpPZlJ@jupiter.tail36e24.ts.net>
Normally, in static builds, the first code that runs is _start, in e.g.
sysdeps/x86_64/start.S, which quickly calls __libc_start_main, passing
it the argv etc. Among the first things __libc_start_main does is
initializing the tunables (based on env), then CPU features, and then
calls _dl_relocate_static_pie (). Specifically, this runs ifunc
resolvers to pick, based on the CPU features discovered earlier, the
most suitable implementation of "string" functions such as memcpy.
Before that point, calling memcpy (or other ifunc-resolved functions)
will not work.
In the Hurd port, things are more complex. In order to get argv/env for
our process, glibc normally needs to do an RPC to the exec server,
unless our args/env are already located on the stack (which is what
happens to bootstrap processes spawned by GNU Mach). Fetching our
argv/env from the exec server has to be done before the call to
__libc_start_main, since we need to know what our argv/env are to pass
them to __libc_start_main.
On the other hand, the implementation of the RPC (and other initial
setup needed on the Hurd before __libc_start_main can be run) is not
very trivial. In particular, it may (and on x86_64, will) use memcpy.
But as described above, calling memcpy before __libc_start_main can not
work, since the GOT entry for it is not yet initialized at that point.
Work around this by pre-filling the GOT entry with the baseline version
of memcpy, __memcpy_sse2_unaligned. This makes it possible for early
calls to memcpy to just work. The initial value of the GOT entry is
unused on x86_64, and changing it won't interfere with the relocation
being performed later: once _dl_relocate_static_pie () is called, the
baseline version will get replaced with the most suitable one, and that
is what subsequent calls of memcpy are going to call.
Checked on x86_64-gnu.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230429201822.2605207-6-bugaevc@gmail.com>
Checked on x86_64-gnu.
[samuel.thibault@ens-lyon.org: Restored same comments as on i386]
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230429201822.2605207-3-bugaevc@gmail.com>
If any of the early boot-up tasks calls exit () or returns from main (),
terminate it properly instead of crashing on trying to dereference
_hurd_ports and getting forcibly terminated by the kernel.
We sadly cannot make the __USEPORT macro do the check for _hurd_ports
being unset, because it evaluates to the value of the expression
provided as the second argument, and that can be of any type; so there
is no single suitable fallback value for the macro to evaluate to in
case _hurd_ports is unset. Instead, each use site that wants to care for
this case will have to do its own checking.
Checked on x86_64-gnu.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230429131354.2507443-4-bugaevc@gmail.com>
There are reports for hang in __check_pf:
https://github.com/JoeDog/siege/issues/4
It is reproducible only under specific configurations:
1. Large number of cores (>= 64) and large number of threads (> 3X of
the number of cores) with long lived socket connection.
2. Low power (frequency) mode.
3. Power management is enabled.
While holding lock, __check_pf calls make_request which calls __sendto
and __recvmsg. Since __sendto and __recvmsg are cancellation points,
lock held by __check_pf won't be released and can cause deadlock when
thread cancellation happens in __sendto or __recvmsg. Add a cancellation
cleanup handler for __check_pf to unlock the lock when cancelled by
another thread. This fixes BZ #20975 and the siege hang issue.
In some cases, we do not want to go through the resolver for function
calls. For example, functions with vector arguments will use vector
registers to pass arguments. In the resolver, we do not save/restore the
vector argument registers for lazy binding efficiency. To avoid ruining
the vector arguments, functions with vector arguments will not go
through the resolver.
To achieve the goal, we will annotate the function symbols with
STO_RISCV_VARIANT_CC flag and add DT_RISCV_VARIANT_CC tag in the dynamic
section. In the first pass on PLT relocations, we do not set up to call
_dl_runtime_resolve. Instead, we resolve the functions directly.
Signed-off-by: Hsiangkai Wang <kai.wang@sifive.com>
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://inbox.sourceware.org/libc-alpha/20230314162512.35802-1-kito.cheng@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
The build of glibc for i686-gnu has been failing for a while with GCC
mainline / GCC 13:
../sysdeps/mach/hurd/getcwd.c: In function '__hurd_canonicalize_directory_name_internal':
../sysdeps/mach/hurd/getcwd.c:242:48: error: pointer 'file_name' may be used after 'realloc' [-Werror=use-after-free]
242 | file_namep = &buf[file_namep - file_name + size / 2];
| ~~~~~~~~~~~^~~~~~~~~~~
../sysdeps/mach/hurd/getcwd.c:236:25: note: call to 'realloc' here
236 | buf = realloc (file_name, size);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
Fix by doing the subtraction before the reallocation.
Tested with build-many-glibcs.py for i686-gnu.
[samuel.thibault@ens-lyon.rg: Removed mention of this being a bug]
Message-Id: <18587337-7815-4056-ebd0-724df262d591@codesourcery.com>
As fixed in 0822e3552a ("hurd: Don't pass FD_CLOEXEC in CMSG_DATA"),
senders currently don't have any flag to pass. We shouldn't blindly take
random flags that senders could be erroneously giving us.
This is a new flag that can be passed to recvmsg () to make it
atomically set the CLOEXEC flag on all the file descriptors received
using the SCM_RIGHTS mechanism. This is useful for all the same reasons
that the other XXX_CLOEXEC flags are useful: namely, it provides
atomicity with respect to another thread of the same process calling
(fork and then) exec at the same time.
This flag is already supported on Linux and FreeBSD. The flag's value,
0x40000, is choosen to match FreeBSD's.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230423160548.126576-2-bugaevc@gmail.com>
The flags are used by _hurd_intern_fd, which takes O_* flags, not FD_*.
Also, it is of no concern to the receiving process whether or not
the sender process wants to close its copy of sent file descriptor
upon exec, and it should not influence whether or not the received
file descriptor gets the FD_CLOEXEC flag set in the receiving process.
The latter should in fact be dependent on the MSG_CMSG_CLOEXEC flag
being passed to the recvmsg () call, which is going to be implemented
in the following commit.
Fixes 344e755248
"hurd: Support sending file descriptors over Unix sockets"
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
This makes the prefer_map_32bit_exec tunable no longer Linux-specific.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230423215526.346009-4-bugaevc@gmail.com>
This is a flag that can be passed to mmap () to request that the mapping
being established should be located in the lower 2 GB area of the
address space, so only the lower 31 (not 32) bits can be set in its
address, and the address can be represented as a 32-bit integer without
truncating it.
This flag is intended to be compatible with Linux, FreeBSD, and Darwin
flags of the same name. Out of those systems, it appears Linux and
FreeBSD take MAP_32BIT to mean "map 31 bit", whereas Darwin allows the
32nd bit to be set in the address as well. The Hurd follows Linux and
FreeBSD behavior.
Unlike on those systems, on the Hurd MAP_32BIT is defined on all
supported architectures (which currently are only i386 and x86_64).
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230423215526.346009-1-bugaevc@gmail.com>
When opening a temporary file without O_CLOEXEC we risk leaking the
file descriptor if another thread calls (fork and then) exec while we
have the fd open. Fix this by consistently passing O_CLOEXEC everywhere
where we open a file for internal use (and not to return it to the user,
in which case the API defines whether or not the close-on-exec flag
shall be set on the returned fd).
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230419160207.65988-4-bugaevc@gmail.com>
Properly differentiate between setting up the real TLS with
TLS_INIT_TP, and setting up the early TLS (__init1_tcbhead) in static
builds. In the latter case, don't yet migrate the reply port into the
TCB, and don't yet set __libc_tls_initialized to 1.
This also lets us move the __init1_desc assignment inside
_hurd_tls_init ().
Fixes cd019ddd89
"hurd: Don't leak __hurd_reply_port0"
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Created tunable glibc.pthread.stack_hugetlb to control when hugepages
can be used for stack allocation.
In case THP are enabled and glibc.pthread.stack_hugetlb is set to
0, glibc will madvise the kernel not to use allow hugepages for stack
allocations.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
We must not use the user's reply port (scp->sc_reply_port) for any of
our own RPCs, otherwise various things break. So, use MACH_PORT_DEAD as
a reply port when destroying our reply port, and make sure to do this
after _hurd_sigstate_unlock (), which may do a gsync_wake () RPC.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Optimize the fast paths (x < y) and (x/y < 2^12). Delay handling of special
cases to reduce the number of instructions executed before the fast paths.
Performance improvements for fmod:
Skylake Zen2 Neoverse V1
subnormals 11.8% 4.2% 11.5%
normal 3.9% 0.01% -0.5%
close-exponents 6.3% 5.6% 19.4%
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
When glibc is built as a shared library, TLS is always initialized by
the call of TLS_INIT_TP () macro made inside the dynamic loader, prior
to running the main program (see dl-call_tls_init_tp.h). We can take
advantage of this: we know for sure that __LIBC_NO_TLS () will evaluate
to 0 in all other cases, so let the compiler know that explicitly too.
Also, only define _hurd_tls_init () and TLS_INIT_TP () under the same
conditions (either !SHARED or inside rtld), to statically assert that
this is the case.
Other than a microoptimization, this also helps with avoiding awkward
sharing of the __libc_tls_initialized variable between ld.so and libc.so
that we would have to do otherwise -- we know for sure that no sharing
is required, simply because __libc_tls_initialized would always be set
to true inside libc.so.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230319151017.531737-25-bugaevc@gmail.com>
Now that the signal code no longer accesses it, the only real user of it
was mig-reply.c, so move the logic for managing the port there.
If we're in SHARED and outside of rtld, we know that __LIBC_NO_TLS ()
always evaluates to 0, and a TLS reply port will always be used, not
__hurd_reply_port0. Still, the compiler does not see that
__hurd_reply_port0 is never used due to its address being taken. To deal
with this, explicitly compile out __hurd_reply_port0 when we know we
won't use it.
Also, instead of accessing the port via THREAD_SELF->reply_port, this
uses THREAD_GETMEM and THREAD_SETMEM directly, avoiding possible
miscompilations.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
This reverts commit b37899d34d.
Apparently we load libc.so (and thus start using its functions) before
calling TLS_INIT_TP, so libc.so functions should not actually assume
that TLS is always set up.
Previously, once we set up TLS, we would implicitly switch from using
__hurd_reply_port0 to reply_port inside the TCB, leaving the former
unused. But we never deallocated it, so it got leaked.
Instead, migrate the port into the new TCB's reply_port slot. This
avoids both the port leak and an extra syscall to create a new reply
port for the TCB.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230319151017.531737-28-bugaevc@gmail.com>
If we're doing signals, that means we've already got the signal thread
running, and that implies TLS having been set up. So we know that
__hurd_local_reply_port will resolve to THREAD_SELF->reply_port, and can
access that directly using the THREAD_GETMEM and THREAD_SETMEM macros.
This avoids potential miscompilations, and should also be a tiny bit
faster.
Also, use mach_port_mod_refs () and not mach_port_destroy () to destroy
the receive right. mach_port_destroy () should *never* be used on
mach_task_self (); this can easily lead to port use-after-free
vulnerabilities if the task has any other references to the same port.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230319151017.531737-26-bugaevc@gmail.com>
When glibc is built as a shared library, TLS is always initialized by
the call of TLS_INIT_TP () macro made inside the dynamic loader, prior
to running the main program (see dl-call_tls_init_tp.h). We can take
advantage of this: we know for sure that __LIBC_NO_TLS () will evaluate
to 0 in all other cases, so let the compiler know that explicitly too.
Also, only define _hurd_tls_init () and TLS_INIT_TP () under the same
conditions (either !SHARED or inside rtld), to statically assert that
this is the case.
Other than a microoptimization, this also helps with avoiding awkward
sharing of the __libc_tls_initialized variable between ld.so and libc.so
that we would have to do otherwise -- we know for sure that no sharing
is required, simply because __libc_tls_initialized would always be set
to true inside libc.so.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230319151017.531737-25-bugaevc@gmail.com>
These are just regular local variables that are not accessed in any
funny ways, not even though a pointer. There's absolutely no reason to
declare them volatile. It only ends up hurting the quality of the
generated machine code.
If anything, it would make sense to decalre sigsp as *pointing* to
volatile memory (volatile void *sigsp), but evidently that's not needed
either.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230403115621.258636-2-bugaevc@gmail.com>
This is based on the Linux port's version, but laid out to match Mach's
struct i386_thread_state, much like the i386 version does.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Rename x86_cpu_INDEX_7_ECX_1 to x86_cpu_INDEX_7_ECX_15 for the unused bit
15 in ECX from CPUID with EAX == 0x7 and ECX == 0.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
sysdeps/mach/hurd/htl/pt-pthread_self.c: New file.
htl/Makefile: .. Add it to libc routine.
sysdeps/mach/hurd/htl/pt-sysdep.c(__pthread_self): Remove it.
sysdeps/mach/hurd/htl/pt-sysdep.h(__pthread_self): Add hidden propertie.
htl/Versions(__pthread_self) Version it as private symbol.
Signed-off-by: Guy-Fleury Iteriteka <gfleury@disroot.org>
Message-Id: <20230318095826.1125734-3-gfleury@disroot.org>
As indicated by sparc kernel-features.h, even though sparc64 defines
__NR_pause, it is not supported (ENOSYS). Always use ppoll or the
64 bit time_t variant instead.
The error handling is moved to sysdeps/ieee754 version with no SVID
support. The compatibility symbol versions still use the wrapper
with SVID error handling around the new code. There is no new symbol
version nor compatibility code on !LIBM_SVID_COMPAT targets
(e.g. riscv).
The ia64 is unchanged, since it still uses the arch specific
__libm_error_region on its implementation. For both i686 and m68k,
which provive arch specific implementation, wrappers are added so
no new symbol are added (which would require to change the
implementations).
It shows an small improvement, the results for fmod:
Architecture | Input | master | patch
-----------------|-----------------|----------|--------
x86_64 (Ryzen 9) | subnormals | 12.5049 | 9.40992
x86_64 (Ryzen 9) | normal | 296.939 | 296.738
x86_64 (Ryzen 9) | close-exponents | 16.0244 | 13.119
aarch64 (N1) | subnormal | 6.81778 | 4.33313
aarch64 (N1) | normal | 155.620 | 152.915
aarch64 (N1) | close-exponents | 8.21306 | 5.76138
armhf (N1) | subnormal | 15.1083 | 14.5746
armhf (N1) | normal | 244.833 | 241.738
armhf (N1) | close-exponents | 21.8182 | 22.457
Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
This uses a new algorithm similar to already proposed earlier [1].
With x = mx * 2^ex and y = my * 2^ey (mx, my, ex, ey being integers),
the simplest implementation is:
mx * 2^ex == 2 * mx * 2^(ex - 1)
while (ex > ey)
{
mx *= 2;
--ex;
mx %= my;
}
With mx/my being mantissa of double floating pointer, on each step the
argument reduction can be improved 8 (which is sizeof of uint32_t minus
MANTISSA_WIDTH plus the signal bit):
while (ex > ey)
{
mx << 8;
ex -= 8;
mx %= my;
} */
The implementation uses builtin clz and ctz, along with shifts to
convert hx/hy back to doubles. Different than the original patch,
this path assume modulo/divide operation is slow, so use multiplication
with invert values.
I see the following performance improvements using fmod benchtests
(result only show the 'mean' result):
Architecture | Input | master | patch
-----------------|-----------------|----------|--------
x86_64 (Ryzen 9) | subnormals | 17.2549 | 12.0318
x86_64 (Ryzen 9) | normal | 85.4096 | 49.9641
x86_64 (Ryzen 9) | close-exponents | 19.1072 | 15.8224
aarch64 (N1) | subnormal | 10.2182 | 6.81778
aarch64 (N1) | normal | 60.0616 | 20.3667
aarch64 (N1) | close-exponents | 11.5256 | 8.39685
I also see similar improvements on arm-linux-gnueabihf when running on
the N1 aarch64 chips, where it a lot of soft-fp implementation (for
modulo, and multiplication):
Architecture | Input | master | patch
-----------------|-----------------|----------|--------
armhf (N1) | subnormal | 11.6662 | 10.8955
armhf (N1) | normal | 69.2759 | 34.1524
armhf (N1) | close-exponents | 13.6472 | 18.2131
Instead of using the math_private.h definitions, I used the
math_config.h instead which is used on newer math implementations.
Co-authored-by: kirill <kirill.okhotnikov@gmail.com>
[1] https://sourceware.org/pipermail/libc-alpha/2020-November/119794.html
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
This uses a new algorithm similar to already proposed earlier [1].
With x = mx * 2^ex and y = my * 2^ey (mx, my, ex, ey being integers),
the simplest implementation is:
mx * 2^ex == 2 * mx * 2^(ex - 1)
while (ex > ey)
{
mx *= 2;
--ex;
mx %= my;
}
With mx/my being mantissa of double floating pointer, on each step the
argument reduction can be improved 11 (which is sizeo of uint64_t minus
MANTISSA_WIDTH plus the signal bit):
while (ex > ey)
{
mx << 11;
ex -= 11;
mx %= my;
} */
The implementation uses builtin clz and ctz, along with shifts to
convert hx/hy back to doubles. Different than the original patch,
this path assume modulo/divide operation is slow, so use multiplication
with invert values.
I see the following performance improvements using fmod benchtests
(result only show the 'mean' result):
Architecture | Input | master | patch
-----------------|-----------------|----------|--------
x86_64 (Ryzen 9) | subnormals | 19.1584 | 12.5049
x86_64 (Ryzen 9) | normal | 1016.51 | 296.939
x86_64 (Ryzen 9) | close-exponents | 18.4428 | 16.0244
aarch64 (N1) | subnormal | 11.153 | 6.81778
aarch64 (N1) | normal | 528.649 | 155.62
aarch64 (N1) | close-exponents | 11.4517 | 8.21306
I also see similar improvements on arm-linux-gnueabihf when running on
the N1 aarch64 chips, where it a lot of soft-fp implementation (for
modulo, clz, ctz, and multiplication):
Architecture | Input | master | patch
-----------------|-----------------|----------|--------
armhf (N1) | subnormal | 15.908 | 15.1083
armhf (N1) | normal | 837.525 | 244.833
armhf (N1) | close-exponents | 16.2111 | 21.8182
Instead of using the math_private.h definitions, I used the
math_config.h instead which is used on newer math implementations.
Co-authored-by: kirill <kirill.okhotnikov@gmail.com>
[1] https://sourceware.org/pipermail/libc-alpha/2020-November/119794.html
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
Linux kernel uses AT_HWCAP2 to indicate if FSGSBASE instructions are
enabled. If the HWCAP2_FSGSBASE bit in AT_HWCAP2 is set, FSGSBASE
instructions can be used in user space. Define dl_check_hwcap2 to set
the FSGSBASE feature to active on Linux when the HWCAP2_FSGSBASE bit is
set.
Add a test to verify that FSGSBASE is active on current kernels.
NB: This test will fail if the kernel doesn't set the HWCAP2_FSGSBASE
bit in AT_HWCAP2 while fsgsbase shows up in /proc/cpuinfo.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
The divss instruction clobbers its first argument, and the constraints
need to reflect that. Fortunately, with GCC 12, generated code does
not actually change, so there is no externally visible bug.
Suggested-by: Jakub Jelinek <jakub@redhat.com>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
Just like the other existing rtld-str* files, this provides rtld with
usable versions of stpncpy and strncpy.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230319151017.531737-22-bugaevc@gmail.com>
The source code is the same as sysdeps/i386/htl/tcb-offsets.sym, but of
course the produced tcb-offsets.h will be different.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230319151017.531737-21-bugaevc@gmail.com>
These do not need any changes to be used on x86_64.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230319151017.531737-20-bugaevc@gmail.com>
This is more correct, if only because these fields are defined as having
the type unsigned int in the Mach headers, so casting them to a signed
int and then back is suboptimal.
Also, remove an extra reassignment of uesp -- this is another remnant of
the ecx kludge.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230319151017.531737-16-bugaevc@gmail.com>
There's nothing Mach- or Hurd-specific about it; any port that ends
up with rtld pulling in strncpy will need this.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230319151017.531737-15-bugaevc@gmail.com>
This was used for the value of libc-lock's owner when TLS is not yet set
up, so THREAD_SELF can not be used. Since the value need not be anything
specific -- it just has to be non-NULL -- we can just use a plain
constant, such as (void *) 1, for this. This avoids accessing the symbol
through GOT, and exporting it from libc.so in the first place.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230319151017.531737-12-bugaevc@gmail.com>
Noone is or should be using __hurd_threadvar_stack_{offset,mask}, we
have proper TLS now. These two remaining variables are never set to
anything other than zero, so any code that would try to use them as
described would just dereference a zero pointer and crash. So remove
them entirely.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230319151017.531737-6-bugaevc@gmail.com>
And make always supported. The configure option was added on glibc 2.25
and some features require it (such as hwcap mask, huge pages support, and
lock elisition tuning). It also simplifies the build permutations.
Changes from v1:
* Remove glibc.rtld.dynamic_sort changes, it is orthogonal and needs
more discussion.
* Cleanup more code.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Prevent sh from interpreting a user string as shell options if it
starts with '-' or '+'. Since the version of /bin/sh used for testing
system() is different from the full-fledged system /bin/sh add support
to it for handling "--" after "-c". Add a testcase to ensure the
expected behavior.
Signed-off-by: Joe Simmons-Talbott <josimmon@redhat.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Instead define the required fields in system dependend files. The only
system dependent definition is FILENAME_MAX, which should match POSIX
PATH_MAX, and it is obtained from either kernel UAPI or mach headers.
Currently set pre-defined value from current kernels.
It avoids a circular dependendy when including stdio.h in
gen-as-const-headers files.
Checked on x86_64-linux-gnu and i686-linux-gnu
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
They are both used by __libc_freeres to free all library malloc
allocated resources to help tooling like mtrace or valgrind with
memory leak tracking.
The current scheme uses assembly markers and linker script entries
to consolidate the free routine function pointers in the RELRO segment
and to be freed buffers in BSS.
This patch changes it to use specific free functions for
libc_freeres_ptrs buffers and call the function pointer array directly
with call_function_static_weak.
It allows the removal of both the internal macros and the linker
script sections.
Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This allows other targets to use the same inputs for their own libmvec
microbenchmarks without having to duplicate them in their own
subdirectory.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Binutils 2.40 sets EF_LARCH_OBJABI_V1 for shared objects:
$ ld --version | head -n1
GNU ld (GNU Binutils) 2.40
$ echo 'int dummy;' > dummy.c
$ cc dummy.c -shared
$ readelf -h a.out | grep Flags
Flags: 0x43, DOUBLE-FLOAT, OBJ-v1
We need to ignore it in ldconfig or ldconfig will consider all shared
objects linked by Binutils 2.40 "unsupported". Maybe we should stop
setting EF_LARCH_OBJABI_V1 for shared objects, but Binutils 2.40 is
already released and we cannot change it.
Linux threads were removed about 12 years ago and the current
nptl implementation only requires 4-byte alignment for pthread
locks.
The 16-byte alignment causes various issues. For example in
building ignition-msgs, we have:
/usr/include/google/protobuf/map.h:124:37: error: static assertion failed
124 | static_assert(alignof(value_type) <= 8, "");
| ~~~~~~~~~~~~~~~~~~~~^~~~
This is caused by the 16-byte pthread lock alignment.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
For better debug experience use separate code block with extra
cfi_* directives to run child (same as in __clone3).
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Use the clone3 wrapper on ARC. It doesn't care about stack alignment.
All callers should provide an aligned stack.
It follows the internal signature:
extern int clone3 (struct clone_args *__cl_args, size_t __size,
int (*__func) (void *__arg), void *__arg);
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Between versions v2.11 and v2.12 struct ntptimeval got new fields.
That wasn't a problem because new function ntp_gettimex was created
(and made default) to support new struct. Old ntp_gettime was not
using new fields so it was safe to call with old struct
definition. Then commits 5613afe9e3 and b6ad64b907 (added for
64 bit time_t support), ntp_gettime start setting new fields.
Sets fields manually to maintain compatibility with v2.11 struct
definition.
Resolves#30156
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
according to man-pages-posix-2017, shm_open() function may fail if the length
of the name argument exceeds {_POSIX_PATH_MAX} and set ENAMETOOLONG
Signed-off-by: abushwang <abushwangs@gmail.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Recorded in [BZ #30183]:
1. export GLIBC_TUNABLES=glibc.cpu.hwcaps=-AVX512
2. Add _dl_printf("p -- %s\n", p); just before switch(nl) in
sysdeps/x86/cpu-tunables.c
3. compiled and run ./testrun.sh /usr/bin/ls
you will get:
p -- -AVX512
p -- LC_ADDRESS=en_US.UTF-8
p -- LC_NUMERIC=C
...
The function, TUNABLE_CALLBACK (set_hwcaps)
(tunable_val_t *valp), checks far more than it should and it
should stop at end of "-AVX512".
Fix bug that SIGCHLD is erroneously blocked forever in the following
scenario:
1. Thread A calls system but hasn't returned yet
2. Thread B calls another system but returns
SIGCHLD would be blocked forever in thread B after its system() returns,
even after the system() in thread A returns.
Although POSIX does not require, glibc system implementation aims to be
thread and cancellation safe. This bug was introduced in
5fb7fc9635 when we moved reverting signal
mask to happen when the last concurrently running system returns,
despite that signal mask is per thread. This commit reverts this logic
and adds a test.
Signed-off-by: Adam Yi <ayi@janestreet.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch updates the kernel version in the tests tst-mman-consts.py,
tst-mount-consts.py and tst-pidfd-consts.py to 6.2. (There are no new
constants covered by these tests in 6.2 that need any other header
changes, and the removed MAP_VARIABLE for hppa was addressed
separately.)
Tested with build-many-glibcs.py.
The __builtin_arm_uqsub8 is an internal GCC builtin which might change
in future release (the correct way is to include "arm_acle.h" and use
__uqsub8 ()). Since not all compilers support it, just use the
inline assembler instead.
Checked on armv7a-linux-gnueabihf.
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
The generic implementation already cover word access along with
cmpbge for both aligned and unaligned, so use it instead.
Checked qemu static for alpha-linux-gnu.
The default, and power7 implementation just adds word aligned
access when inputs have the same aligment. The unaligned case
is still done by byte operations.
This is already covered by the generic implementation, which also add
the unaligned input optimization.
Checked on powerpc64-linux-gnu built without multi-arch for powerpc64,
power7, power8, and power9 (build for le).
Reviewed-by: Rajalakshmi Srinivasaraghavan <rajis@linux.ibm.com>
The default, power4, and power7 implementation just adds word aligned
access when inputs have the same aligment. The unaligned case
is still done by byte operations.
This is already covered by the generic implementation, which also add
the unaligned input optimization.
Checked on powerpc-linux-gnu built without multi-arch for powerpc,
power4, and power7.
Reviewed-by: Rajalakshmi Srinivasaraghavan <rajis@linux.ibm.com>
C2x adds binary integer constants starting with 0b or 0B, and supports
those constants for the %i scanf format (in addition to the %b format,
which isn't yet implemented for scanf in glibc). Implement that scanf
support for glibc.
As with the strtol support, this is incompatible with previous C
standard versions, in that such an input string starting with 0b or 0B
was previously required to be parsed as 0 (with the rest of the input
potentially matching subsequent parts of the scanf format string).
Thus this patch adds 12 new __isoc23_* functions per long double
format (12, 24 or 36 depending on how many long double formats the
glibc configuration supports), with appropriate header redirection
support (generally very closely following that for the __isoc99_*
scanf functions - note that __GLIBC_USE (DEPRECATED_SCANF) takes
precedence over __GLIBC_USE (C2X_STRTOL), so the case of GNU
extensions to C89 continues to get old-style GNU %a and does not get
this new feature). The function names would remain as __isoc23_* even
if C2x ends up published in 2024 rather than 2023.
When scanf %b support is added, I think it will be appropriate for all
versions of scanf to follow C2x rules for inputs to the %b format
(given that there are no compatibility concerns for a new format).
Tested for x86_64 (full glibc testsuite). The first version was also
tested for powerpc (32-bit) and powerpc64le (stdio-common/ and wcsmbs/
tests), and with build-many-glibcs.py.
Before GCC r13-2728, it would produce a normal dynamic-linked executable
with -static-pie. I mistakely believed it would produce a static-linked
executable, so failed to detect the breakage. Then with Binutils 2.40
and (vanilla) GCC 12, libc_cv_static_pie_on_loongarch is mistakenly
enabled and cause a building failure with "undefined reference to
_DYNAMIC".
Fix the issue by disabling static PIE if -static-pie creates something
with a INTERP header.
"We don't need it any more"
The INTR_MSG_TRAP macro in intr-msg.h used to play little trick with
the stack pointer: it would temporarily save the "real" stack pointer
into ecx, while setting esp to point to just before the message buffer,
and then invoke the mach_msg trap. This way, INTR_MSG_TRAP reused the
on-stack arguments laid out for the containing call of
_hurd_intr_rpc_mach_msg (), passing them to the mach_msg trap directly.
This, however, required special support in hurdsig.c and trampoline.c,
since they now had to recognize when a thread is inside the piece of
code where esp doesn't point to the real tip of the stack, and handle
this situation specially.
Commit 1d20f33ff4 has removed the actual
temporary change of esp by actually re-pushing mach_msg arguments onto
the stack, and popping them back at end. It did not, however, deal with
the rest of "the ecx kludge" code in other files, resulting in potential
crashes if a signal arrives in the middle of pushing arguments onto the
stack.
Fix that by removing "the ecx kludge". Instead, when we want a thread
to skip the RPC, but cannot make just make it jump to after the trap
since it's not done adjusting the stack yet, set the SYSRETURN register
to MACH_SEND_INTERRUPTED (as we do anyway), and rely on the thread
itself for detecting this case and skipping the RPC.
This simplifies things somewhat and paves the way for a future x86_64
port of this code.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230301162355.426887-1-bugaevc@gmail.com>
The _FPU_SETCW and _FPU_GETCW macros are defined with inline assemblies.
They use the sfpc and efpc instructions, respectively. But both contain
a spurious second operand that leads to a compile error with Clang.
Removing this operand works both with gcc/gas (since binutils 2.18) as
well as with clang/llvm.
Needed due to recent commits:
- "added pair of inputs for hypotf in binary32"
commit ID cf7ffdd8a5
- "update auto-libm-test-out-hypot"
commit ID 3efbf11fdf
Linux 6.2 adds six new Arm HWCAP values and two new HWCAP2 values; add
them to glibc's Arm bits/hwcap.h, with corresponding dl-procinfo.c and
dl-procinfo.h updates.
Tested with build-many-glibcs.py for arm-linux-gnueabi.
This is for future-proofing. On i386, it is 4-byte aligned anyway, but
on x86_64, we want it 8-byte aligned, not 4-byte aligned.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230214173722.428140-4-bugaevc@gmail.com>
Update libm test ulps for
commit 3efbf11fdf
Author: Paul Zimmermann <Paul.Zimmermann@inria.fr>
Date: Tue Feb 14 11:24:59 2023 +0100
update auto-libm-test-out-hypot
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This patch implements the LoongArch specific math barriers in order to omit
the store and load from stack if possible.
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The Linux kernel upstream commit 71bdea6f798b ("parisc: Align parisc
MADV_XXX constants with all other architectures") dropped the
parisc-specific MADV_* values in favour of the same constants as
other architectures. In the same commit a wrapper was added which
translates the old values to the standard MADV_* values to avoid
breakage of existing programs.
This upstream patch has been downported to all stable kernel trees as
well.
This patch now drops the parisc specific constants from glibc to
allow newly compliled programs to use the standard MADV_* constants.
v2: Added NEWS section, based on feedback from Florian Weimer
Signed-off-by: Helge Deller <deller@gmx.de>
This drops all of the return address rewriting kludges. The only
remaining hack is the jump out of a call stack while adjusting the
stack pointer.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Linux 6.2 has no new syscalls. Update the version number in
syscall-names.list to reflect that it is still current for 6.2.
Tested with build-many-glibcs.py.
Crossing 2GB boundaries with indirect calls and jumps can use more
branch prediction resources on Intel Golden Cove CPU (see the
"Misprediction for Branches >2GB" section in Intel 64 and IA-32
Architectures Optimization Reference Manual.) There is visible
performance improvement on workloads with many PLT calls when executable
and shared libraries are mmapped below 2GB. Add the Prefer_MAP_32BIT_EXEC
bit so that mmap will try to map executable or denywrite pages in shared
libraries with MAP_32BIT first.
NB: Prefer_MAP_32BIT_EXEC reduces bits available for address space
layout randomization (ASLR), which is always disabled for SUID programs
and can only be enabled by the tunable, glibc.cpu.prefer_map_32bit_exec,
or the environment variable, LD_PREFER_MAP_32BIT_EXEC. This works only
between shared libraries or between shared libraries and executables with
addresses below 2GB. PIEs are usually loaded at a random address above
4GB by the kernel.
Linux 6.2 removed the hppa compatibility MAP_VARIABLE define. That
means that, whether or not we remove it in glibc, it needs to be
ignored in tst-mman-consts.py (since this macro comparison
infrastructure expects that new kernel header versions only add new
macros, not remove old ones).
Tested with build-many-glibcs.py for hppa-linux-gnu (Linux 6.2
headers).
Fix the computation to allow for cntfrq_el0 being larger than 1GHz.
Assume cntfrq_el0 is a multiple of 1MHz to increase the maximum
interval (1024 seconds at 1GHz).
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
It fixes the build after 7ea510127e and 22999b2f0f.
Checked with build for s390x-linux-gnu with -march=z13.
Reviewed-by: Arjun Shankar <arjun@redhat.com>
__builtin_arm_uqsub8 is only available on gcc newer or equal than 10.
Checked on arm-linux-gnueabihf built with gcc 9.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
The default Linux implementation already handled the Linux generic
ABIs interface used on newer architectures, so there is no need to
Imply the generic any longer.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
And disable if kernel does not support it.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
And disable if kernel does not support it.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
And remove redundant entries on other architectures Version. The
version for fallocate64 was supposed to be 2.10, but it was then
added to 32-bit platforms in 2.11 because it mistakenly wasn't
exported for them in 2.10 (see the commit message for
1f3615a1c9).
The linux/generic did not exist before 2.15, i.e. when the tile
ports were added (and microblaze did not exist before 2.18), which
explains those differences but also illustrates that "2.11 for 32-bit,
2.10 for 64-bit" should be sufficient since versions older than the
minimum for the architecture are automatically adjusted.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
While cleaning up old libc version support, the deprecated libc4 code was
accidentally kept in `implicit_soname`, instead of the libc6 code.
This causes additional symlinks to be created by `ldconfig` for libraries
without a soname, e.g. a library `libsomething.123.456.789` without a soname
will create a `libsomething.123` -> `libsomething.123.456.789` symlink.
As the libc6 version of the `implicit_soname` code is a trivial `xstrdup`,
just inline it and remove `implicit_soname` altogether.
Some further simplification looks possible (e.g. the call to `create_links`
looks like a no-op if `soname == NULL`, other than the verbose printfs), but
logic is kept as-is for now.
Fixes: BZ #30125
Fixes: 8ee878592c ("Assume only FLAG_ELF_LIBC6 suport")
Signed-off-by: Joan Bruguera <joanbrugueram@gmail.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
And make it a bit more 64-bit ready. This is in preparation to moving this
file into x86/
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230218203717.373211-6-bugaevc@gmail.com>
This ensures that a timer_t value can be cast to struct timer_node *
and back.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230218203717.373211-5-bugaevc@gmail.com>
Fix a few more cases of build errors caused by mismatched types. This is a
continuation of f4315054b4.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230218203717.373211-3-bugaevc@gmail.com>
This is going to be done differently on x86_64.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230218203717.373211-2-bugaevc@gmail.com>
Add extra check for compiler definitions to ensure that compiler provides
sqrt and fma hw fpu instructions else use software implementation.
As divide/sqrt and FMA hw support from CPU side is optional,
the compiler can be configured by options to generate hw FPU instructions,
but without use of FDDIV, FDSQRT, FSDIV, FSSQRT, FDMADD and FSMADD
instructions. In this case __builtin_sqrt and __builtin_sqrtf provided by
compiler can't be used inside the glibc code, as these builtins are used
in implementations of sqrt() and sqrtf() functions but at the same time
these builtins unfold to sqrt() and sqrtf(). So it is possible to receive
code like that:
0001c4b4 <__ieee754_sqrtf>:
1c4b4: 0001 0000 b 0 ;1c4b4 <__ieee754_sqrtf>
The same is also true for __builtin_fma and __builtin_fmaf.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The ARCv2 ABI requires 4 byte stack pointer alignment. Don't allow to
use unaligned child stack in clone. As the stack grows down,
align it down.
This was pointed by misc/tst-misalign-clone-internal and
misc/tst-misalign-clone tests. Stack alignmet fixes these tests
fails.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
And use a packed structure instead. The compiler generates optimized
unaligned code if the architecture supports it.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
Builds for s390 recently started failing with:
../sysdeps/s390/multiarch/ifunc-impl-list.c: In function '__libc_ifunc_impl_list':
../sysdeps/s390/multiarch/ifunc-impl-list.c:83:21: error: unused variable 'dl_hwcap' [-Werror=unused-variable]
83 | unsigned long int dl_hwcap = features->hwcap;
| ^~~~~~~~
https://sourceware.org/pipermail/libc-testresults/2023q1/010855.html
Add __attribute__ ((unused)) as already done for another variable
there.
Tested with build-many-glibcs.py (compilers and glibcs) for
s390x-linux-gnu and s390-linux-gnu.
Note: s390x-linux-gnu-O3 started failing with a different error
earlier; that problem may still need to be fixed after this fix is in.
https://sourceware.org/pipermail/libc-testresults/2023q1/010829.html
C2x adds binary integer constants starting with 0b or 0B, and supports
those constants in strtol-family functions when the base passed is 0
or 2. Implement that strtol support for glibc.
As discussed at
<https://sourceware.org/pipermail/libc-alpha/2020-December/120414.html>,
this is incompatible with previous C standard versions, in that such
an input string starting with 0b or 0B was previously required to be
parsed as 0 (with the rest of the string unprocessed). Thus, as
proposed there, this patch adds 20 new __isoc23_* functions with
appropriate header redirection support. This patch does *not* do
anything about scanf %i (which will need 12 new functions per long
double variant, so 12, 24 or 36 depending on the glibc configuration),
instead leaving that for a future patch. The function names would
remain as __isoc23_* even if C2x ends up published in 2024 rather than
2023.
Making this change leads to the question of what should happen to
internal uses of these functions in glibc and its tests. The header
redirection (which applies for _GNU_SOURCE or any other feature test
macros enabling C2x features) has the effect of redirecting internal
uses but without those uses then ending up at a hidden alias (see the
comment in include/stdio.h about interaction with libc_hidden_proto).
It seems desirable for the default for internal uses to be the same
versions used by normal code using _GNU_SOURCE, so rather than doing
anything to disable that redirection, similar macro definitions to
those in include/stdio.h are added to the include/ headers for the new
functions.
Given that the default for uses in glibc is for the redirections to
apply, the next question is whether the C2x semantics are correct for
all those uses. Uses with the base fixed to 10, 16 or any other value
other than 0 or 2 can be ignored. I think this leaves the following
internal uses to consider (an important consideration for review of
this patch will be both whether this list is complete and whether my
conclusions on all entries in it are correct):
benchtests/bench-malloc-simple.c
benchtests/bench-string.h
elf/sotruss-lib.c
math/libm-test-support.c
nptl/perf.c
nscd/nscd_conf.c
nss/nss_files/files-parse.c
posix/tst-fnmatch.c
posix/wordexp.c
resolv/inet_addr.c
rt/tst-mqueue7.c
soft-fp/testit.c
stdlib/fmtmsg.c
support/support_test_main.c
support/test-container.c
sysdeps/pthread/tst-mutex10.c
I think all of these places are OK with the new semantics, except for
resolv/inet_addr.c, where the POSIX semantics of inet_addr do not
allow for binary constants; thus, I changed that file (to use
__strtoul_internal, whose semantics are unchanged) and added a test
for this case. In the case of posix/wordexp.c I think accepting
binary constants is OK since POSIX explicitly allows additional forms
of shell arithmetic expressions, and in stdlib/fmtmsg.c SEV_LEVEL is
not in POSIX so again I think accepting binary constants is OK.
Functions such as __strtol_internal, which are only exported for
compatibility with old binaries from when those were used in inline
functions in headers, have unchanged semantics; the __*_l_internal
versions (purely internal to libc and not exported) have a new
argument to specify whether to accept binary constants.
As well as for the standard functions, the header redirection also
applies to the *_l versions (GNU extensions), and to legacy functions
such as strtoq, to avoid confusing inconsistency (the *q functions
redirect to __isoc23_*ll rather than needing their own __isoc23_*
entry points). For the functions that are only declared with
_GNU_SOURCE, this means the old versions are no longer available for
normal user programs at all. An internal __GLIBC_USE_C2X_STRTOL macro
is used to control the redirections in the headers, and cases in glibc
that wish to avoid the redirections - the function implementations
themselves and the tests of the old versions of the GNU functions -
then undefine and redefine that macro to allow the old versions to be
accessed. (There would of course be greater complexity should we wish
to make any of the old versions into compat symbols / avoid them being
defined at all for new glibc ABIs.)
strtol_l.c has some similarity to strtol.c in gnulib, but has already
diverged some way (and isn't listed at all at
https://sourceware.org/glibc/wiki/SharedSourceFiles unlike strtoll.c
and strtoul.c); I haven't made any attempts at gnulib compatibility in
the changes to that file.
I note incidentally that inttypes.h and wchar.h are missing the
__nonnull present on declarations of this family of functions in
stdlib.h; I didn't make any changes in that regard for the new
declarations added.
This macro from Mach headers conflicts with how
sysdeps/x86_64/multiarch/strcmp-sse2.S expects it to be defined.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230214173722.428140-3-bugaevc@gmail.com>
* Micro-optimize TLS access using GCC's native support for gs-based
addressing when available;
* Just use THREAD_GETMEM and THREAD_SETMEM instead of more inline
assembly;
* Sync tcbhead_t layout with NPTL, in particular update/fix __private_ss
offset;
* Statically assert that the two offsets that are a part of ABI are what
we expect them to be.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230214173722.428140-2-bugaevc@gmail.com>
'sem' is the opaque 'sem_t', 'isem' is the actual 'struct new_sem'.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230212111044.610942-6-bugaevc@gmail.com>
It has been decided that on x86_64, mach_msg_type_number_t stays 32-bit.
Therefore, it's not possible to use mach_msg_type_number_t
interchangeably with size_t, in particular this breaks when a pointer to
a variable is passed to a MIG routine.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230212111044.610942-3-bugaevc@gmail.com>
Make the code flow more linear using early returns where possible. This
makes it so much easier to reason about what runs on error / successful
code paths.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230212111044.610942-2-bugaevc@gmail.com>
We used to use .cfi_adjust_cfa_offset around %esp manipulation
asm instructions to fix unwinding, but when building glibc with
-fno-omit-frame-pointer this is bogus since in that case %ebp is the CFA and
does not move.
Instead, let's force -fno-omit-frame-pointer when building intr-msg.c so
that %ebp can always be used and no .cfi_adjust_cfa_offset is needed.
It follows the internal signature:
extern int clone3 (struct clone_args *__cl_args, size_t __size,
int (*__func) (void *__arg), void *__arg);
The powerpc64 ABI requires an initial stackframe so the child can
store/restore the TOC. It is create prior calling clone3 by
adjusting the stack size (since kernel will compute the stack as
stack plus size).
Checked on powerpc64-linux-gnu (power8, kernel 6.0) and
powerpc64le-linux-gnu (power9, kernel 4.18).
Reviewed-by: Paul E. Murphy <murphyp@linux.ibm.com>
Although static linker can optimize it to local call, it follows the
internal scheme to provide hidden proto and definitions.
Reviewed-by: Carlos Eduardo Seo <carlos.seo@linaro.org>
Although static linker can optimize it to local call, it follows the
internal scheme to provide hidden proto and definitions.
Reviewed-by: Carlos Eduardo Seo <carlos.seo@linaro.org>
The hard float abi and hard float are different,
Hard float abi: Use float register to pass float type arguments.
Hard float: Enable the hard float ISA feature.
So the with_fp_cond cannot represent these two features. When
-mfloat-abi=softfp, the float abi is soft and hard float is enabled.
So add 'with_hard_float_abi' in preconfigure and define 'CSKY_HARD_FLOAT_ABI'
if float abi is hard, and use 'CSKY_HARD_FLOAT_ABI' to determine
dynamic linker because it is what determines compatibility.
And with_fp_cond is still needed to tell glibc whether to enable
hard floating feature.
In addition, use AC_TRY_COMMAND to test gcc to ensure compatibility
between different versions of gcc. The original way has a problem
that __CSKY_HARD_FLOAT_FPU_SF__ means the target only has single
hard float-points ISA, so it's not defined in CPUs like ck810f.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch enables the option to influence hwcaps and stfle bits used
by the s390 specific ifunc-resolvers. The currently x86-specific
tunable glibc.cpu.hwcaps is also used on s390x to achieve the task. In
addition the user can also set a CPU arch-level like z13 instead of
single HWCAP and STFLE features.
Note that the tunable only handles the features which are really used
in the IFUNC-resolvers. All others are ignored as the values are only
used inside glibc. Thus we can influence:
- HWCAP_S390_VXRS (z13)
- HWCAP_S390_VXRS_EXT (z14)
- HWCAP_S390_VXRS_EXT2 (z15)
- STFLE_MIE3 (z15)
The influenced hwcap/stfle-bits are stored in the s390-specific
cpu_features struct which also contains reserved fields for future
usage.
The ifunc-resolvers and users of stfle bits are adjusted to use the
information from cpu_features struct.
On 31bit, the ELF_MACHINE_IRELATIVE macro is now also defined.
Otherwise the new ifunc-resolvers segfaults as they depend on
the not yet processed_rtld_global_ro@GLIBC_PRIVATE relocation.
It uses the bitmanip extension to optimize index_fist and index_last
with clz/ctz (using generic implementation that routes to compiler
builtin) and orc.b to check null bytes.
Checked the string test on riscv64 user mode.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
While ppc has the more important string functions in assembly,
there are still a few generic routines used.
Use the Power 6 CMPB insn for testing of zeros.
Checked on powerpc64le-linux-gnu.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
While arm has the more important string functions in assembly,
there are still a few generic routines used.
Use the UQSUB8 insn for testing of zeros.
Checked on armv7-linux-gnueabihf
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
While alpha has the more important string functions in assembly,
there are still a few for find the generic routines are used.
Use the CMPBGE insn, via the builtin, for testing of zeros. Use a
simplified expansion of __builtin_ctz when the insn isn't available.
Checked on alpha-linux-gnu.
Co-authored-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Use UXOR,SBZ to test for a zero byte within a word. While we can
get semi-decent code out of asm-goto, we would do slightly better
with a compiler builtin.
For index_zero et al, sequential testing of bytes is less expensive than
any tricks that involve a count-leading-zeros insn that we don't have.
Checked on hppa-linux-gnu.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
GCC's combine pass cannot merge (x >> c | y << (32 - c)) into a
double-word shift unless (1) the subtract is in the same basic block
and (2) the result of the subtract is used exactly once. Neither
condition is true for any use of MERGE.
By forcing the use of a double-word shift, we not only reduce
contention on SAR, but also allow the setting of SAR to be hoisted
outside of a loop.
Checked on hppa-linux-gnu.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
It also cleanups the multiple inclusion by leaving the ifunc
implementation to undef the weak_alias and libc_hidden_def.
Co-authored-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
New algorithm read the first aligned address and mask off the
unwanted bytes (this strategy is similar to arch-specific
implementations used on powerpc, sparc, and sh).
The loop now read word-aligned address and check using the has_eq
macro.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc-linux-gnu,
and powerpc64-linux-gnu by removing the arch-specific assembly
implementation and disabling multi-arch (it covers both LE and BE
for 64 and 32 bits).
Co-authored-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
New algorithm now calls strchrnul.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc-linux-gnu,
and powerpc64-linux-gnu by removing the arch-specific assembly
implementation and disabling multi-arch (it covers both LE and BE
for 64 and 32 bits).
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
New algorithm read the first aligned address and mask off the unwanted
bytes (this strategy is similar to arch-specific implementations used
on powerpc, sparc, and sh).
The loop now read word-aligned address and check using the has_zero_eq
function.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc64-linux-gnu,
and powerpc-linux-gnu by removing the arch-specific assembly
implementation and disabling multi-arch (it covers both LE and BE
for 64 and 32 bits).
Co-authored-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
New algorithm read the first aligned address and mask off the
unwanted bytes (this strategy is similar to arch-specific
implementations used on powerpc, sparc, and sh).
The loop now read word-aligned address and check using the has_zero
macro.
Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc-linux-gnu,
and powercp64-linux-gnu by removing the arch-specific assembly
implementation and disabling multi-arch (it covers both LE and BE
for 64 and 32 bits).
Co-authored-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
This patch adds generic string find and detection meant to be used in
generic vectorized string implementation. The idea is to decompose the
basic string operation so each architecture can reimplement if it
provides any specialized hardware instruction.
The 'string-misc.h' provides miscellaneous functions:
- extractbyte: extracts the byte from an specific index.
- repeat_bytes: setup an word by replicate the argument on each byte.
The 'string-fza.h' provides zero byte detection functions:
- find_zero_low, find_zero_all, find_eq_low, find_eq_all,
find_zero_eq_low, find_zero_eq_all, and find_zero_ne_all
The 'string-fzb.h' provides boolean zero byte detection functions:
- has_zero: determine if any byte within a word is zero.
- has_eq: determine byte equality between two words.
- has_zero_eq: determine if any byte within a word is zero along with
byte equality between two words.
The 'string-fzi.h' provides positions for string-fza.h results:
- index_first: return index of first zero byte within a word.
- index_last: return index of first byte different between two words.
The 'string-fzc.h' provides a combined version of fza and fzi:
- index_first_zero_eq: return index of first zero byte within a word or
first byte different between two words.
- index_first_zero_ne: return index of first zero byte within a word or
first byte equal between two words.
- index_last_zero: return index of last zero byte within a word.
- index_last_eq: return index of last byte different between two words.
The 'string-shift.h' provides a way to mask off parts of a work based on
some alignmnet (to handle unaligned arguments):
- shift_find, shift_find_last.
Co-authored-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
It moves OP_T_THRES out of memcopy.h to its own header and adjust
each architecture that redefines it.
Checked with a build and check with run-built-tests=no for all major
Linux ABIs.
Co-authored-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
It moves the op_t definition out to an specific header, adds
the attribute 'may-alias', and cleanup its duplicated definitions.
Checked with a build and check with run-built-tests=no for all major
Linux ABIs.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Improve SVE memcpy by copying 2 vectors if the size is small enough.
This improves performance of random memcpy by ~9% on Neoverse V1, and
33-64 byte copies are ~16% faster.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
This file is not used today since we end up using
sysdeps/i386/htl/machine-sp.h. Getting the stack pointer does not need
to be hurd specific and can go into sysdeps/<arch>.
Message-Id: <Y9tpWs2WOgE/Duiq@jupiter.tail36e24.ts.net>
This adds a special SHM_ANON value that can be passed into shm_open ()
in place of a name. When called in this way, shm_open () will create a
new anonymous shared memory file. The file will be created in the same
way that other shared memory files are created (i.e., under /dev/shm/),
except that it is not given a name and therefore cannot be reached from
the file system, nor by other calls to shm_open (). This is accomplished
by utilizing O_TMPFILE.
This is intended to be compatible with FreeBSD's API of the same name.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230130125216.6254-4-bugaevc@gmail.com>
This is a flag that causes open () to create a new, unnamed file in the
same filesystem as the given directory. The file descriptor can be
simply used in the creating process as a temporary file, or shared with
children processes via fork (), or sent over a Unix socket. The file can
be left anonymous, in which case it will be deleted from the backing
file system once all copies of the file descriptor are closed, or given
a permanent name with a linkat () call, such as the following:
int fd = open ("/tmp", O_TMPFILE | O_RDWR, 0700);
/* Do something with the file... */
linkat (fd, "", AT_FDCWD, "/tmp/filename", AT_EMPTY_PATH);
In between creating the file and linking it to the file system, it is
possible to set the file content, mode, ownership, author, and other
attributes, so that the file visibly appears in the file system (perhaps
replacing another file) atomically, with all of its attributes already
set up.
The Hurd support for O_TMPFILE directly exposes the dir_mkfile RPC to
user programs. Previously, dir_mkfile was used by glibc internally, in
particular for implementing tmpfile (), but not exposed to user programs
through a Unix-level API.
O_TMPFILE was initially introduced by Linux. This implementation is
intended to be compatible with the Linux implementation, except that the
O_EXCL flag is not given the special meaning when used together with
O_TMPFILE, unlike on Linux.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20230130125216.6254-3-bugaevc@gmail.com>
Add an optimization to avoid calling clone3 when glibc detects that
there is no kernel support. It also adds __ASSUME_CLONE3, which allows
skipping this optimization and issuing the clone3 syscall directly.
It does not handle the the small window between 5.3 and 5.5 for
posix_spawn (CLONE_CLEAR_SIGHAND was added in 5.5).
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
It follow the internal signature:
extern int clone3 (struct clone_args *__cl_args, size_t __size,
int (*__func) (void *__arg), void *__arg);
Checked on aarch64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The clone3 flag resets all signal handlers of the child not set to
SIG_IGN to SIG_DFL. It allows to skip most of the sigaction calls
to setup child signal handling, where previously a posix_spawn
had to issue 2 times NSIG sigaction calls (one to obtain the current
disposition and another to set either SIG_DFL or SIG_IGN).
With POSIX_SPAWN_SETSIGDEF the child will setup the signal for the case
where the disposition is SIG_IGN.
The code must handle the fallback where clone3 is not available. This is
done by splitting __clone_internal_fallback from __clone_internal.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
All internal callers of __clone3 should provide an already aligned
stack. Removing the stack alignment in __clone3 is a net gain: it
simplifies the internal function contract (mask/unmask signals) along
with the arch-specific code.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Different than kernel, clone3 returns EINVAL for NULL struct
clone_args or function pointer. This is similar to clone
interface that return EINVAL for NULL function argument.
It also clean up the Linux clone3.h interface, since it not
currently exported.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
There is no need to issue another sigaction if the disposition is
already SIG_DFL.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Occurs when `src` has no null-term.
Two cases:
1) Zero-length check is doing:
```
test %rdx, %rdx
jl L(zero_len)
```
which doesn't actually check zero (was at some point `decq` and the
flag never got updated).
The fix is just make the flag `jle` i.e:
```
test %rdx, %rdx
jle L(zero_len)
```
2) Length check in page-cross case checking if we should continue is
doing:
```
cmpq %r8, %rdx
jb L(page_cross_small)
```
which means we will continue searching for null-term if length ends at
the end of a page and there was no null-term in `src`.
The fix is to make the flag:
```
cmpq %r8, %rdx
jbe L(page_cross_small)
```
All AMD architectures cache details will be computed based on
__cpuid__ `0x8000_001D` and the reference to __cpuid__ `0x8000_0006` will be
zeroed out for future architectures.
Reviewed-by: Premachandra Mallappa <premachandra.mallappa@amd.com>
Use shrn for narrowing the mask which simplifies code and speeds up small
strings. Unroll the first search loop to improve performance on large
strings.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Optimize strnlen using the shrn instruction and improve the main loop.
Small strings are around 10% faster, large strings are 40% faster on
modern CPUs.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Simplify calculation of the mask using shrn. Unroll the main loop.
Small strings are 20% faster on modern CPUs.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
Use shrn for the mask, merge tst+bne into cbnz, and tweak code alignment.
Performance improves slightly as a result.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
The patch suppress the same warnings from 87c266d758,
that shows issues for microblaze, mips soft-fp, nios2, and or1k.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Fix the following issues with built-in function use in
sysdeps/ieee754/ldbl-128 and sysdeps/ieee754/float128:
* fabsl used __builtin_fabsf128 unconditionally, breaking the build
with GCC 6 for several architectures; it should use __builtin_fabsl
with an appropriate redirection in float128_private.h. (I'm not
particularly concerned with building glibc with GCC 6; rather, I
want to be able to run the tgmath.h tests with GCC 6, which is a
significantly different case for tgmath.h compared to GCC 7 and
later because of the lack of _FloatN / _FloatNx support in the
compiler, and at present running the tests with a compiler means
building glibc with that compiler.)
* Some (conditional) uses of built-in functions had been added to
ldbl-128 without appropriate float128_private.h remapping (there was
remapping for the macros controlling whether the built-in functions
are used, just not for the functions themselves).
* s_llrintl.c called __builtin_round not __builtin_llrintl, which is
obviously wrong.
Tested with build-many-glibcs.py for aarch64-linux-gnu, GCC 6 (where
it fixes the glibc build) and GCC 12, and with the glibc testsuite for
x86_64.
The minimum non_temporal_threshold is 0x4040. non_temporal_threshold may
be set to less than the minimum value when the shared cache size isn't
available (e.g., in an emulator) or by the tunable. Add checks for
minimum and maximum of non_temporal_threshold.
This fixes BZ #29953.
If the value changes between sem_wait's read and the gsync_wait call,
the kernel will return KERN_INVALID_ARGUMENT, which we have to interpret
as the value having already changed.
This fixes applications (e.g. libgo) seeing sem_wait erroneously return
KERN_INVALID_ARGUMENT.
The kernel actually verifies it, and a garbage value in the register
causes improper system call failures.
Fixes commit c1c0dea388 ("Linux: Remove epoll_create,
inotify_init from syscalls.list") and commit d1d23b1342
("Lninux: consolidate epoll_create implementation").
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This patch increases the value of SIGSTKSZ and MINSIGSTKSZ
for powerpc64 similar to the kernel commit
2f82ec19757f58549467db568c56e7dfff8af283 to allow
further expansion of the signal stack frame size.
This patch updates the kernel version in the tests tst-mman-consts.py,
tst-mount-consts.py and tst-pidfd-consts.py to 6.1. (There are no new
constants covered by these tests in 6.1 that need any other header
changes.)
Tested with build-many-glibcs.py.
vfprintf is entangled with vfwprintf (of course), __printf_fp,
__printf_fphex, __vstrfmon_l_internal, and the strfrom family of
functions. The latter use the internal snprintf functionality,
so vsnprintf is converted as well.
The simples conversion is __printf_fphex, followed by
__vstrfmon_l_internal and __printf_fp, and finally
__vfprintf_internal and __vfwprintf_internal. __vsnprintf_internal
and strfrom* are mostly consuming the new interfaces, so they
are comparatively simple.
__printf_fp is a public symbol, so the FILE *-based interface
had to preserved.
The __printf_fp rewrite does not change the actual binary-to-decimal
conversion algorithm, and digits are still not emitted directly to
the target buffer. However, the staging buffer now uses bytes
instead of wide characters, and one buffer copy is eliminated.
The changes are at least performance-neutral in my testing.
Floating point printing and snprintf improved measurably, so that
this Lua script
for i=1,5000000 do
print(i, i * math.pi)
end
runs about 5% faster for me. To preserve fprintf performance for
a simple "%d" format, this commit has some logic changes under
LABEL (unsigned_number) to avoid additional function calls. There
are certainly some very easy performance improvements here: binary,
octal and hexadecimal formatting can easily avoid the temporary work
buffer (the number of digits can be computed ahead-of-time using one
of the __builtin_clz* built-ins). Decimal formatting can use a
specialized version of _itoa_word for base 10.
The existing (inconsistent) width handling between strfmon and printf
is preserved here. __print_fp_buffer_1 would have to use
__translated_number_width to achieve ISO conformance for printf.
Test expectations in libio/tst-vtables-common.c are adjusted because
the internal staging buffer merges all virtual function calls into
one.
In general, stack buffer usage is greatly reduced, particularly for
unbuffered input streams. __printf_fp can still use a large buffer
in binary128 mode for %g, though.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Their presence causes stub warnings to be created on architectures
which do not implement them.
Fixes commit d1d23b1342 ("Lninux: consolidate
epoll_create implementation") and commit 842128f160
("Linux: consolidate inotify_init implementation").
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
8b8c768e3c ("Force use of -ffreestanding when checking for gnumach
headers") was passing -ffreestanding to CFLAGS only, but headers checks are
performed with the preprocessor, so we rather need to pass it to CPPFLAGS.
Without this ./configure assumes that we are in a fully hosted
environment, which might not be the case. After this patch, we can rely on
the freestanding header files provided by GCC such as stdint.h.
Message-Id: <Y5+0V9osFc/zXMq0@mars>
In the case of INCORRECT usage of `memcmp(a, b, N)` where `a` and `b`
are concurrently modified as `memcmp` runs, there can be a SIGSEGV
in `L(ret_nonzero_vec_end_0)` because the sequential logic
assumes that `(rdx - 32 + rax)` is a positive 32-bit integer.
To be clear, this change does not mean the usage of `memcmp` is
supported. The program behaviour is undefined (UB) in the
presence of data races, and `memcmp` is incorrect when the values
of `a` and/or `b` are modified concurrently (data race). This UB
may manifest itself as a SIGSEGV. That being said, if we can
allow the idiomatic use cases, like those in yottadb with
opportunistic concurrency control (OCC), to execute without a
SIGSEGV, at no cost to regular use cases, then we can aim to
minimize harm to those existing users.
The fix replaces a 32-bit `addl %edx, %eax` with the 64-bit variant
`addq %rdx, %rax`. The 1-extra byte of code size from using the
64-bit instruction doesn't contribute to overall code size as the
next target is aligned and has multiple bytes of `nop` padding
before it. As well all the logic between the add and `ret` still
fits in the same fetch block, so the cost of this change is
basically zero.
The relevant sequential logic can be seen in the following
pseudo-code:
```
/*
* rsi = a
* rdi = b
* rdx = len - 32
*/
/* cmp a[0:15] and b[0:15]. Since length is known to be [17, 32]
in this case, this check is also assumed to cover a[0:(31 - len)]
and b[0:(31 - len)]. */
movups (%rsi), %xmm0
movups (%rdi), %xmm1
PCMPEQ %xmm0, %xmm1
pmovmskb %xmm1, %eax
subl %ecx, %eax
jnz L(END_NEQ)
/* cmp a[len-16:len-1] and b[len-16:len-1]. */
movups 16(%rsi, %rdx), %xmm0
movups 16(%rdi, %rdx), %xmm1
PCMPEQ %xmm0, %xmm1
pmovmskb %xmm1, %eax
subl %ecx, %eax
jnz L(END_NEQ2)
ret
L(END2):
/* Position first mismatch. */
bsfl %eax, %eax
/* The sequential version is able to assume this value is a
positive 32-bit value because the first check included bytes in
range a[0:(31 - len)] and b[0:(31 - len)] so `eax` must be
greater than `31 - len` so the minimum value of `edx` + `eax` is
`(len - 32) + (32 - len) >= 0`. In the concurrent case, however,
`a` or `b` could have been changed so a mismatch in `eax` less or
equal than `(31 - len)` is possible (the new low bound is `(16 -
len)`. This can result in a negative 32-bit signed integer, which
when zero extended to 64-bits is a random large value this out
out of bounds. */
addl %edx, %eax
/* Crash here because 32-bit negative number in `eax` zero
extends to out of bounds 64-bit offset. */
movzbl 16(%rdi, %rax), %ecx
movzbl 16(%rsi, %rax), %eax
```
This fix is quite simple, just make the `addl %edx, %eax` 64 bit (i.e
`addq %rdx, %rax`). This prevents the 32-bit zero extension
and since `eax` is still a low bound of `16 - len` the `rdx + rax`
is bound by `(len - 32) - (16 - len) >= -16`. Since we have a
fixed offset of `16` in the memory access this must be in bounds.
A recent GCC change resulted in localplt test failures on sparc64
because of references to _Qp_fgt. This is analogous to all the other
floating-point symbols allowed in localplt.data, so it seems
appropriate to allow this one as well.
Tested with build-many-glibcs.py for sparc64-linux-gnu (GCC mainline),
where it fixes the test failure.
The generic (sysdeps/unix/sysv/linux/generic/bits/typesizes.h) and
default (bits/typesizes.h) differs in two fields:
bits/typesizes.h Linux generic
__NLINK_T_TYPE __UWORD_TYPE __U32_TYPE
__BLKSIZE_T_TYPE __SLONGWORD_TYPE __S32_TYPE
Sinceit leads to different C++ mangling names, the default typesize.h
is copied for the requires archtiectures and the generic is make the
default Linux one.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
It is currently used for csky, arc, nios2, and or1k. Newer 64 bit
architecture, like riscv32 and loongarch, reimplement it to override
F_GETLK64/F_SETLK64/F_SETLKW64.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
The includes chain is added on each architecture sysdep.h and
the __NR__llseek hack is moved to lseek.c and lseek64.c.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
And disable if kernel does not support it.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
And disable if kernel does not support it.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
And disable if kernel does not support it.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
And disable if kernel does not support it.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
And disable if kernel does not support it.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
This is similar to other LFS consolidation, where the non-LFS is only
built if __OFF_T_MATCHES_OFF64_T is not defined and the LFS version
is aliased to non-LFS name if __OFF_T_MATCHES_OFF64_T is defined.
For non-LFS variant, use sendfile syscall if defined, otherwise use
sendfile64 plus the offset overflow check (as generic implementation).
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Use unlink syscall if defined, otherwise use unlinkat.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Use symlink syscall if defined, otherwise use symlinkat.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Use rmdir syscall if defined, otherwise use unlinkat.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Use readlink syscall if defined, otherwise readlinkat.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Use mkdir syscall if defined, otherwise use mkdirat.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Use link syscall if defined, otherwise use linkat.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Use lchown syscall if defined, otherwise use fchownat.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Use inotify_init syscall if defined, otherwise use inotify_init1.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Use epoll_create syscall if defined, otherwise use epoll_create1.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Use dup2 syscall if defined, otherwise use dup3.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Use chown syscall if defined, otherwise use fchownat.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Use chmod syscall if defined, otherwise use fchmodat.
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
Use the generic implementation as the default, since the syscall
is supported by all architectures.
Also cleanup some headers and remove the INTERNAL_SYSCALL_ERROR_P
usage (the INTERNAL_SYSCALL_CALL macro already returns an negative
value if an error occurs).
The linux syscall ABI returns long, so the generic syscall code for
linux should use long for the return value.
This fixes the truncation of the return value of the syscall function
when that does not fit into an int.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The assembler is not issued directly, but rather always through CC
wrapper. The binutils version check if done with LD instead.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Previously, getrandom would, each time it's called, traverse the file
system to find /dev/urandom, fetch some random data from it, then throw
away that port. This is quite slow, while calls to getrandom are
genrally expected to be fast.
Additionally, this means that getrandom can not work when /dev/urandom
is unavailable, such as inside a chroot that lacks one. User programs
expect calls to getrandom to work inside a chroot if they first call
getrandom outside of the chroot.
In particular, this is known to break the OpenSSH server, and in that
case the issue is exacerbated by the API of arc4random, which prevents
it from properly reporting errors, forcing glibc to abort on failure.
This causes sshd to just die once it tries to generate a random number.
Caching the random server port, in a manner similar to how socket
server ports are cached, both improves the performance and works around
the chroot issue.
Tested on i686-gnu with the following program:
pthread_barrier_t barrier;
void *worker(void*) {
pthread_barrier_wait(&barrier);
uint32_t sum = 0;
for (int i = 0; i < 10000; i++) {
sum += arc4random();
}
return (void *)(uintptr_t) sum;
}
int main() {
pthread_t threads[THREAD_COUNT];
pthread_barrier_init(&barrier, NULL, THREAD_COUNT);
for (int i = 0; i < THREAD_COUNT; i++) {
pthread_create(&threads[i], NULL, worker, NULL);
}
for (int i = 0; i < THREAD_COUNT; i++) {
void *retval;
pthread_join(threads[i], &retval);
printf("Thread %i: %lu\n", i, (unsigned long)(uintptr_t) retval);
}
In my totally unscientific benchmark, with this patch, this completes
in about 7 seconds, whereas previously it took about 50 seconds. This
program was also used to test that getrandom () doesn't explode if the
random server dies, but instead reopens the /dev/urandom anew. I have
also verified that with this patch, OpenSSH can once again accept
connections properly.
Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
Message-Id: <20221202135558.23781-1-bugaevc@gmail.com>
This patch cleans up the power4 strncmp optimization for powerpc64 which
is unlikely to be used anywhere.
Tested on ppc64le with and without --disable-multi-arch flag.
Reviewed-by: Paul E. Murphy <murphyp@linux.ibm.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
On x32, the size_t parameter may be passed in the lower 32 bits of a
64-bit register with the non-zero upper 32 bits. The string/memory
functions written in assembly can only use the lower 32 bits of a
64-bit register as length or must clear the upper 32 bits before using
the full 64-bit register for length.
This pach fixes strncpy for x32. Tested on x86-64 and x32. On x86-64,
libc.so is the same with and without the fix.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
On x32, the size_t parameter may be passed in the lower 32 bits of a
64-bit register with the non-zero upper 32 bits. The string/memory
functions written in assembly can only use the lower 32 bits of a
64-bit register as length or must clear the upper 32 bits before using
the full 64-bit register for length.
This pach fixes strncat for x32. Tested on x86-64 and x32. On x86-64,
libc.so is the same with and without the fix.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
Add inline assembler for the scalbn functions. Passes GLIBC regression.
GCC 13, LoongArch support ___builtin_scalbn{,f} with -fno-math-errno,
but only "libm" can use -fno-math-errno in GLIBC, and scalbn is in libc
instead of libm because __printf_fp calls it.
GCC 13 compiles these built-ins instead of generic
implementation for function logb.
Link: https://gcc.gnu.org/r13-3922
Co-Authored-By: Xi Ruoyao <xry111@xry111.site>
This patch is using the corresponding GCC builtin for logbf, logb,
logbl and logbf128 if the USE_FUNCTION_BUILTIN macros are defined to one
in math-use-builtins-function.h.
Co-Authored-By: Xi Ruoyao <xry111@xry111.site>
GCC 13 compiles these built-ins instead of generic
implementation for function llrint.
Link: https://gcc.gnu.org/r13-3920
Co-Authored-By: Xi Ruoyao <xry111@xry111.site>
This patch is using the corresponding GCC builtin for llrintf, llrint,
llrintl and llrintf128 if the USE_FUNCTION_BUILTIN macros are defined to one
in math-use-builtins-function.h.
Co-Authored-By: Xi Ruoyao <xry111@xry111.site>
GCC 13 compiles these built-ins instead of generic
implementation for function lrint.
Link: https://gcc.gnu.org/r13-3920
Co-Authored-By: Xi Ruoyao <xry111@xry111.site>
This patch is using the corresponding GCC builtin for lrintf, lrint,
lrintl and lrintf128 if the USE_FUNCTION_BUILTIN macros are defined to one
in math-use-builtins-function.h.
Co-Authored-By: Xi Ruoyao <xry111@xry111.site>
lld does not implement all the linker optimization to avoid the GOT
relocation as done by binutils (bfd/elf32-i386.c:elf_i386_convert_load_reloc).
The current 'movl main@GOT(%ebx), %eax' will then create a GOT
relocation when building with lld, which make static-pie status to
not being able to start the provided main function.
The change uses a __wrap_main local symbol, which in turn calls main
(similar as used by aarch64 and s390x).
Checked on i686-linux-gnu with binutils and lld.
Reviewed-by: Fangrui Song <maskray@google.com>
This patch fixes two problems with audit:
1. The DL_OFFSET_RV_VPCS offset was mixed up with DL_OFFSET_RG_VPCS,
resulting in x2 register value nulling in RG structure.
2. We need to preserve the x8 register before function call, but
don't have to save it's new value and restore it before return.
Anyway the final restore was using OFFSET_RV instead of OFFSET_RG value
which is wrong (althoug doesn't affect anything).
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Currently glibc uses in_time_t_range to detects time_t overflow,
and if it occurs fallbacks to 64 bit syscall version.
The function name is confusing because internally time_t might be
either 32 bits or 64 bits (depending on __TIMESIZE).
This patch refactors the in_time_t_range by replacing it with
in_int32_t_range for the case to check if the 64 bit time_t syscall
should be used.
The in_time_t range is used to detect overflow of the
syscall return value.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Use __builtin_{fma, fmaf} to implement function {fma, fmaf} instead of
the generic implementation.
* sysdeps/loongarch/fpu/math-use-builtins-fma.h: New file.
Old applications pass __IPC_64 as part of the command argument because
old glibc did not check for unknown commands, and passed through the
arguments directly to the kernel, without adding __IPC_64.
Applications need to continue doing that for old glibc compatibility,
so this commit enables this approach in current glibc.
For msgctl and shmctl, if no translation is required, make
direct system calls, as we did before the time64 changes. If
translation is required, mask __IPC_64 from the command argument.
For semctl, the union-in-vararg argument handling means that
translation is needed on all architectures.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
RISC-V architecture extends the cache information for level 3 cache
in AUX vector in Linux v.6.1-rc1. This patch supports sysconf to get
the level 3 cache information.
Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
Implemented:
wcscat-avx2 (+ 744 bytes
wcscpy-avx2 (+ 539 bytes)
wcpcpy-avx2 (+ 577 bytes)
wcsncpy-avx2 (+1108 bytes)
wcpncpy-avx2 (+1214 bytes)
wcsncat-avx2 (+1085 bytes)
Performance Changes:
Times are from N = 10 runs of the benchmark suite and are reported
as geometric mean of all ratios of New Implementation / Best Old
Implementation. Best Old Implementation was determined with the
highest ISA implementation.
wcscat-avx2 -> 0.975
wcscpy-avx2 -> 0.591
wcpcpy-avx2 -> 0.698
wcsncpy-avx2 -> 0.730
wcpncpy-avx2 -> 0.711
wcsncat-avx2 -> 0.954
Code Size Changes:
This change increase the size of libc.so by ~5.5kb bytes. For
reference the patch optimizing the normal strcpy family functions
decreases libc.so by ~5.2kb.
Full check passes on x86-64 and build succeeds for all ISA levels w/
and w/o multiarch.
Implemented:
wcscat-evex (+ 905 bytes)
wcscpy-evex (+ 674 bytes)
wcpcpy-evex (+ 709 bytes)
wcsncpy-evex (+1358 bytes)
wcpncpy-evex (+1467 bytes)
wcsncat-evex (+1213 bytes)
Performance Changes:
Times are from N = 10 runs of the benchmark suite and are reported
as geometric mean of all ratios of New Implementation / Best Old
Implementation. Best Old Implementation was determined with the
highest ISA implementation.
wcscat-evex -> 0.991
wcscpy-evex -> 0.587
wcpcpy-evex -> 0.695
wcsncpy-evex -> 0.719
wcpncpy-evex -> 0.694
wcsncat-evex -> 0.979
Code Size Changes:
This change increase the size of libc.so by ~6.3kb bytes. For
reference the patch optimizing the normal strcpy family functions
decreases libc.so by ~5.7kb.
Full check passes on x86-64 and build succeeds for all ISA levels w/
and w/o multiarch.
Optimizations are:
1. Use more overlapping stores to avoid branches.
2. Reduce how unrolled the aligning copies are (this is more of a
code-size save, its a negative for some sizes in terms of
perf).
3. For st{r|p}n{cat|cpy} re-order the branches to minimize the
number that are taken.
Performance Changes:
Times are from N = 10 runs of the benchmark suite and are
reported as geometric mean of all ratios of
New Implementation / Old Implementation.
strcat-avx2 -> 0.998
strcpy-avx2 -> 0.937
stpcpy-avx2 -> 0.971
strncpy-avx2 -> 0.793
stpncpy-avx2 -> 0.775
strncat-avx2 -> 0.962
Code Size Changes:
function -> Bytes New / Bytes Old -> Ratio
strcat-avx2 -> 685 / 1639 -> 0.418
strcpy-avx2 -> 560 / 903 -> 0.620
stpcpy-avx2 -> 592 / 939 -> 0.630
strncpy-avx2 -> 1176 / 2390 -> 0.492
stpncpy-avx2 -> 1268 / 2438 -> 0.520
strncat-avx2 -> 1042 / 2563 -> 0.407
Notes:
1. Because of the significant difference between the
implementations they are split into three files.
strcpy-avx2.S -> strcpy, stpcpy, strcat
strncpy-avx2.S -> strncpy
strncat-avx2.S > strncat
I couldn't find a way to merge them without making the
ifdefs incredibly difficult to follow.
Full check passes on x86-64 and build succeeds for all ISA levels w/
and w/o multiarch.
Optimizations are:
1. Use more overlapping stores to avoid branches.
2. Reduce how unrolled the aligning copies are (this is more of a
code-size save, its a negative for some sizes in terms of
perf).
3. Improve the loop a bit (similiar to what we do in strlen with
2x vpminu + kortest instead of 3x vpminu + kmov + test).
4. For st{r|p}n{cat|cpy} re-order the branches to minimize the
number that are taken.
Performance Changes:
Times are from N = 10 runs of the benchmark suite and are
reported as geometric mean of all ratios of
New Implementation / Old Implementation.
stpcpy-evex -> 0.922
strcat-evex -> 0.985
strcpy-evex -> 0.880
strncpy-evex -> 0.831
stpncpy-evex -> 0.780
strncat-evex -> 0.958
Code Size Changes:
function -> Bytes New / Bytes Old -> Ratio
strcat-evex -> 819 / 1874 -> 0.437
strcpy-evex -> 700 / 1074 -> 0.652
stpcpy-evex -> 735 / 1094 -> 0.672
strncpy-evex -> 1397 / 2611 -> 0.535
stpncpy-evex -> 1489 / 2691 -> 0.553
strncat-evex -> 1184 / 2832 -> 0.418
Notes:
1. Because of the significant difference between the
implementations they are split into three files.
strcpy-evex.S -> strcpy, stpcpy, strcat
strncpy-evex.S -> strncpy
strncat-evex.S > strncat
I couldn't find a way to merge them without making the
ifdefs incredibly difficult to follow.
2. All implementations can be made evex512 by including
"x86-evex512-vecs.h" at the top.
3. All implementations have an optional define:
`USE_EVEX_MASKED_STORE`
Setting to one uses evex-masked stores for handling short
strings. This saves code size and branches. It's disabled
for all implementations are the moment as there are some
serious drawbacks to masked stores in certain cases, but
that may be fixed on future architectures.
Full check passes on x86-64 and build succeeds for all ISA levels w/
and w/o multiarch.
Changes to generated code are:
1. In a few places use `vpcmpeqb` instead of `vpcmpneq` to save a
byte of code size.
2. Add a branch for length <= (VEC_SIZE * 6) as opposed to doing
the entire block of [VEC_SIZE * 4 + 1, VEC_SIZE * 8] in a
single basic-block (the space to add the extra branch without
changing code size is bought with the above change).
Change (2) has roughly a 20-25% speedup for sizes in [VEC_SIZE * 4 +
1, VEC_SIZE * 6] and negligible to no-cost for [VEC_SIZE * 6 + 1,
VEC_SIZE * 8]
From N=10 runs on Tigerlake:
align1,align2 ,length ,result ,New Time ,Cur Time ,New Time / Old Time
0 ,0 ,129 ,0 ,5.404 ,6.887 ,0.785
0 ,0 ,129 ,1 ,5.308 ,6.826 ,0.778
0 ,0 ,129 ,18446744073709551615 ,5.359 ,6.823 ,0.785
0 ,0 ,161 ,0 ,5.284 ,6.827 ,0.774
0 ,0 ,161 ,1 ,5.317 ,6.745 ,0.788
0 ,0 ,161 ,18446744073709551615 ,5.406 ,6.778 ,0.798
0 ,0 ,193 ,0 ,6.804 ,6.802 ,1.000
0 ,0 ,193 ,1 ,6.950 ,6.754 ,1.029
0 ,0 ,193 ,18446744073709551615 ,6.792 ,6.719 ,1.011
0 ,0 ,225 ,0 ,6.625 ,6.699 ,0.989
0 ,0 ,225 ,1 ,6.776 ,6.735 ,1.003
0 ,0 ,225 ,18446744073709551615 ,6.758 ,6.738 ,0.992
0 ,0 ,256 ,0 ,5.402 ,5.462 ,0.989
0 ,0 ,256 ,1 ,5.364 ,5.483 ,0.978
0 ,0 ,256 ,18446744073709551615 ,5.341 ,5.539 ,0.964
Rewriting with VMM API allows for memcmpeq-evex to be used with
evex512 by including "x86-evex512-vecs.h" at the top.
Complete check passes on x86-64.
The only change to the existing generated code is `tzcnt` -> `bsf` to
save a byte of code size here and there.
Rewriting with VMM API allows for memcmp-evex-movbe to be used with
evex512 by including "x86-evex512-vecs.h" at the top.
Complete check passes on x86-64.
Similar to ppoll, the poll.h header needs to redirect the poll call
to a proper fortified ppoll with 64 bit time_t support.
The implementation is straightforward, just need to add a similar
check as __poll_chk and call the 64 bit time_t ppoll version. The
debug fortify tests are also extended to cover 64 bit time_t for
affected ABIs.
Unfortunately it requires an aditional symbol, which makes backport
tricky. One possibility is to add a static inline version if compiler
supports is and call abort instead of __chk_fail, so fortified version
will call __poll64 in the end.
Another possibility is to just remove the fortify support for
_TIME_BITS=64.
Checked on i686-linux-gnu.
Changes from v1:
Use vec api for register.
Replace VPCMP with VPCMPEQ
Restructure and remove 1 unconditional jump.
Change page cross logic to use sall.
This patch implements following evex512 version of string functions.
evex512 version takes up to 30% less cycle as compared to evex,
depending on length and alignment.
- strrchr function using 512 bit vectors.
- wcsrchr function using 512 bit vectors.
Code size data:
strrchr-evex.o 879 byte
strrchr-evex512.o 601 byte (-32%)
wcsrchr-evex.o 882 byte
wcsrchr-evex512.o 572 byte (-35%)
Placeholder function, not used by any processor at the moment.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
This makes it more likely that the compiler can compute the strlen
argument in _startup_fatal at compile time, which is required to
avoid a dependency on strlen this early during process startup.
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
The old exception handling implementation used function interposition
to replace the dynamic loader implementation (no TLS support) with the
libc implementation (TLS support). This results in problems if the
link order between the dynamic loader and libc is reversed (bug 25486).
The new implementation moves the entire implementation of the
exception handling functions back into the dynamic loader, using
THREAD_GETMEM and THREAD_SETMEM for thread-local data support.
These depends on Hurd support for these macros, added in commit
b65a82e4e7 ("hurd: Add THREAD_GET/SETMEM/_NC").
One small obstacle is that the exception handling facilities are used
before the TCB has been set up, so a check is needed if the TCB is
available. If not, a regular global variable is used to store the
exception handling information.
Also rename dl-error.c to dl-catch.c, to avoid confusion with the
dlerror function.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Commit 6e8a0aac2f ("time: Fix overflow itimer tests on 32-bit
systems") changed in_time_t_range to assume a 32-bit time_t. This broke
fstatat on MIPSn64 that was using it with a 64-bit time_t due to
difference between stat and stat64. This commit fix that by adding a
MIPSn64 specific version, which bypasses the EOVERFLOW tests.
Resolves: BZ #29730
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
clang emits an warning when a double alias redirection is used, to warn
the the original symbol will be used even when weak definition is
overridden. However, this is a common pattern for weak_alias, where
multiple alias are set to same symbol.
Reviewed-by: Fangrui Song <maskray@google.com>
GCC 13 has added more _FloatN and _FloatNx versions of existing
<math.h> and <complex.h> built-in functions, for use in libstdc++-v3.
This breaks the glibc build because of how those functions are defined
as aliases to functions with the same ABI but different types. Add
appropriate -fno-builtin-* options for compiling relevant files, as
already done for the case of long double functions aliasing double
ones and based on the list of files used there.
I fixed some mistakes in that list of double files that I noticed
while implementing this fix, but there may well be more such
(harmless) cases, in this list or the new one (files that don't
actually exist or don't define the named functions as aliases so don't
need the options). I did try to exclude cases where glibc doesn't
define certain functions for _FloatN or _FloatNx types at all from the
new uses of -fno-builtin-* options. As with the options for double
files (see the commit message for commit
49348beafe, "Fix build with GCC 10 when
long double = double."), it's deliberate that the options are used
even if GCC currently doesn't have a built-in version of a given
functions, so providing some level of future-proofing against more
such built-in functions being added in future.
Tested with build-many-glibcs.py for aarch64-linux-gnu
powerpc-linux-gnu powerpc64le-linux-gnu x86_64-linux-gnu (compilers
and glibcs builds) with GCC mainline.
This patch improves following functionality
- Replace VPCMP with VPCMPEQ.
- Replace page cross check logic with sall.
- Remove extra lea from align_more.
- Remove uncondition loop jump.
- Use bsf to check max length in first vector.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
According to the specification of ISO/IEC TS 18661-1:2014,
The strfromd, strfromf, and strfroml functions are equivalent to
snprintf(s, n, format, fp) (7.21.6.5), except the format string contains only
the character %, an optional precision that does not contain an asterisk *, and
one of the conversion specifiers a, A, e, E, f, F, g, or G, which applies to
the type (double, float, or long double) indicated by the function suffix
(rather than by a length modifier). Use of these functions with any other 20
format string results in undefined behavior.
strfromf will convert the arguement with type float to double first.
According to the latest version of IEEE754 which is published in 2019,
Conversion of a quiet NaN from a narrower format to a wider format in the same
radix, and then back to the same narrower format, should not change the quiet
NaN payload in any way except to make it canonical.
When either an input or result is a NaN, this standard does not interpret the
sign of a NaN. However, operations on bit strings—copy, negate, abs,
copySign—specify the sign bit of a NaN result, sometimes based upon the sign
bit of a NaN operand. The logical predicates totalOrder and isSignMinus are
also affected by the sign bit of a NaN operand. For all other operations, this
standard does not specify the sign bit of a NaN result, even when there is only
one input NaN, or when the NaN is produced from an invalid operation.
converting NAN or -NAN with type float to double doesn't need to keep
the signbit. As a result, this test case isn't mandatory.
The problem is that according to RISC-V ISA manual in chapter 11.3 of
riscv-isa-20191213,
Except when otherwise stated, if the result of a floating-point operation is
NaN, it is the canonical NaN. The canonical NaN has a positive sign and all
significand bits clear except the MSB, a.k.a. the quiet bit. For
single-precision floating-point, this corresponds to the pattern 0x7fc00000.
which means that conversion -NAN from float to double won't keep the signbit.
Since glibc ought to be consistent here between types and architectures, this
patch adds copysign to fix this problem if the string is NAN. This patch
adds two different functions under sysdeps directory to work around the
issue.
This patch has been tested on x86_64 and riscv64.
Resolves: BZ #29501
v2: Change from macros to different inline functions.
v3: Add unlikely check to isnan.
v4: Fix wrong commit message header.
v5: Fix style: add space before parentheses.
v6: Add copyright.
Signed-off-by: Letu Ren <fantasquex@gmail.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The extension header is two 32bit words and in the last header both
should be 0. There is plenty space in the __reserved area, but it's
better not to write more than we mean to.
Use an empty wordcopy.c to avoid building the generic one.
It does not seem to be used anywhere.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This consolidates the destructor invocations from _dl_fini and
dlclose. Remove the micro-optimization that avoids
calling _dl_call_fini if they are no destructors (as dlclose is quite
expensive anyway). The debug log message is now printed
unconditionally.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This allows the rest of dynamic loader to check whether the TCB
has been set up (and THREAD_GETMEM and THREAD_SETMEM will work).
Reviewed-by: Siddhesh Poyarekar <siddhesh@gotplt.org>
Since __memcpy_simd is the fastest memcpy on almost all cores, replace
the generic memcpy with it. If SVE is available, a SVE memcpy will be
used by default (including for Neoverse N2).
This patch implements following evex512 version of string functions.
evex512 version takes up to 30% less cycle as compared to evex,
depending on length and alignment.
- strchrnul function using 512 bit vectors.
- strchr function using 512 bit vectors.
- wcschr function using 512 bit vectors.
Code size data:
strchrnul-evex.o 599 byte
strchrnul-evex512.o 569 byte (-5%)
strchr-evex.o 639 byte
strchr-evex512.o 595 byte (-7%)
wcschr-evex.o 644 byte
wcschr-evex512.o 607 byte (-6%)
Placeholder function, not used by any processor at the moment.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
The generic Linux struct_stat misses the conditionals to use
bits/struct_stat_time64_helper.h in the __USE_TIME_BITS64 for
architecture that uses __TIMESIZE == 32 (currently csky and nios2).
Since newer ports should not support 32 bit time_t, the generic
implementation should be used as default.
For arm, hppa, and sh a copy of default struct_stat is added,
while for csky and nios a new one based on generic is used, along
with conditionals to use bits/struct_stat_time64_helper.h.
The default struct_stat is also replaced with the generic one.
Checked on aarch64-linux-gnu and arm-linux-gnueabihf.
Detecting an overflow edge case depended on signed overflow of a long
long. Replace the additions and the overflow checks by
__builtin_add_overflow().
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
The builtin bswap is already used if optimziation is enabled for
GCC 4.8+, so glibc symbols will be used in a very limited scenarios.
Also, gcc generated code is quite similar to all but ia64 and i386
htons.
Checked on alpha, i686, and ia64.
Generic implementation on top of __bswap_32 always expands
inline to either bswap or movbe depending on -march=*.
Signed-off-by: Cristian Rodríguez <crrodriguez@opensuse.org>
Avoid moving code across SET_RESTORE_ROUNDL in order to fix
[BZ #29463].
Tested-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
Linux 6.0 adds a constant ADDRB, a termios c_cflag bit, to its
include/uapi/asm-generic/termbits-common.h.
Add it accordingly to glibc's bits/termios-c_cflag.h headers. As
other constants in these headers are generally in octal, I converted
the value to octal to match. As ADDRB isn't in a POSIX-reserved
namespace, I made it conditional on __USE_MISC.
Tested for x86_64.
Unused at the moment, but evex512 strcmp, strncmp, strcasecmp{l}, and
strncasecmp{l} functions can be added by including strcmp-evex.S with
"x86-evex512-vecs.h" defined.
In addition save code size a bit in a few places.
1. tzcnt ... -> bsf ...
2. vpcmp{b|d} $0 ... -> vpcmpeq{b|d}
This saves a touch of code size but has minimal net affect.
Full check passes on x86-64.
commit b412213eee
Author: Noah Goldstein <goldstein.w.n@gmail.com>
Date: Tue Oct 18 17:44:07 2022 -0700
x86: Optimize strrchr-evex.S and implement with VMM headers
Added `vpcompress{b|d}` to the page-cross logic with is an
AVX512-VBMI2 instruction. This is not supported on SKX. Since the
page-cross logic is relatively cold and the benefit is minimal
revert the page-cross case back to the old logic which is supported
on SKX.
Tested on x86-64.
The ARM preconfigure script tries to detect the capabilities of the
target platform by checking the compiler's predefined architecture
macros. However, if the compiler is tuning for AArch32 on ARMv8/v9 this
step fails:
checking for sysdeps preconfigure fragments... aarch64 alpha arc arm
WARNING: arm/preconfigure: Did not find ARM architecture type; using default
This is because preconfigure.ac doesn't escape the square brackets in
the glob for matching compilers targeting ARMv8. Adding another pair of
brackets to escape the first pair fixes this:
checking for sysdeps preconfigure fragments... aarch64 alpha arc arm
Found compiler is configured for something newer than v7 - using v7
Signed-off-by: Felix Riemann <felix.riemann@sma.de>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The current macros uses pid as signed value, which triggers a compiler
warning for process and thread timers. Replace MAKE_PROCESS_CPUCLOCK
with static inline function that expects the pid as unsigned. These
are similar to what Linux does internally.
Checked on x86_64-linux-gnu.
Reviewed-by: Arjun Shankar <arjun@redhat.com>
Optimization is:
1. Cache latest result in "fast path" loop with `vmovdqu` instead of
`kunpckdq`. This helps if there are more than one matches.
Code Size Changes:
strrchr-evex.S : +30 bytes (Same number of cache lines)
Net perf changes:
Reported as geometric mean of all improvements / regressions from N=10
runs of the benchtests. Value as New Time / Old Time so < 1.0 is
improvement and 1.0 is regression.
strrchr-evex.S : 0.932 (From cases with higher match frequency)
Full results attached in email.
Full check passes on x86-64.
Optimizations are:
1. Use the fact that lzcnt(0) -> VEC_SIZE for memchr to save a branch
in short string case.
2. Save several instructions in len = [VEC_SIZE, 4 * VEC_SIZE] case.
3. Use more code-size efficient instructions.
- tzcnt ... -> bsf ...
- vpcmpb $0 ... -> vpcmpeq ...
Code Size Changes:
memrchr-evex.S : -29 bytes
Net perf changes:
Reported as geometric mean of all improvements / regressions from N=10
runs of the benchtests. Value as New Time / Old Time so < 1.0 is
improvement and 1.0 is regression.
memrchr-evex.S : 0.949 (Mostly from improvements in small strings)
Full results attached in email.
Full check passes on x86-64.
Optimizations are:
1. Use the fact that bsf(0) leaves the destination unchanged to save a
branch in short string case.
2. Restructure code so that small strings are given the hot path.
- This is a net-zero on the benchmark suite but in general makes
sense as smaller sizes are far more common.
3. Use more code-size efficient instructions.
- tzcnt ... -> bsf ...
- vpcmpb $0 ... -> vpcmpeq ...
4. Align labels less aggressively, especially if it doesn't save fetch
blocks / causes the basic-block to span extra cache-lines.
The optimizations (especially for point 2) make the strnlen and
strlen code essentially incompatible so split strnlen-evex
to a new file.
Code Size Changes:
strlen-evex.S : -23 bytes
strnlen-evex.S : -167 bytes
Net perf changes:
Reported as geometric mean of all improvements / regressions from N=10
runs of the benchtests. Value as New Time / Old Time so < 1.0 is
improvement and 1.0 is regression.
strlen-evex.S : 0.992 (No real change)
strnlen-evex.S : 0.947
Full results attached in email.
Full check passes on x86-64.
Size Optimizations:
1. Condence hot path for better cache-locality.
- This is most impact for strchrnul where the logic strings with
len <= VEC_SIZE or with a match in the first VEC no fits entirely
in the first cache line.
2. Reuse common targets in first 4x VEC and after the loop.
3. Don't align targets so aggressively if it doesn't change the number
of fetch blocks it will require and put more care in avoiding the
case where targets unnecessarily split cache lines.
4. Align the loop better for DSB/LSD
5. Use more code-size efficient instructions.
- tzcnt ... -> bsf ...
- vpcmpb $0 ... -> vpcmpeq ...
6. Align labels less aggressively, especially if it doesn't save fetch
blocks / causes the basic-block to span extra cache-lines.
Code Size Changes:
strchr-evex.S : -63 bytes
strchrnul-evex.S: -48 bytes
Net perf changes:
Reported as geometric mean of all improvements / regressions from N=10
runs of the benchtests. Value as New Time / Old Time so < 1.0 is
improvement and 1.0 is regression.
strchr-evex.S (Fixed) : 0.971
strchr-evex.S (Rand) : 0.932
strchrnul-evex.S : 0.965
Full results attached in email.
Full check passes on x86-64.
Optimizations are:
1. Use the fact that tzcnt(0) -> VEC_SIZE for memchr to save a branch
in short string case.
2. Restructure code so that small strings are given the hot path.
- This is a net-zero on the benchmark suite but in general makes
sense as smaller sizes are far more common.
3. Use more code-size efficient instructions.
- tzcnt ... -> bsf ...
- vpcmpb $0 ... -> vpcmpeq ...
4. Align labels less aggressively, especially if it doesn't save fetch
blocks / causes the basic-block to span extra cache-lines.
The optimizations (especially for point 2) make the memchr and
rawmemchr code essentially incompatible so split rawmemchr-evex
to a new file.
Code Size Changes:
memchr-evex.S : -107 bytes
rawmemchr-evex.S : -53 bytes
Net perf changes:
Reported as geometric mean of all improvements / regressions from N=10
runs of the benchtests. Value as New Time / Old Time so < 1.0 is
improvement and 1.0 is regression.
memchr-evex.S : 0.928
rawmemchr-evex.S : 0.986 (Less targets cross cache lines)
Full results attached in email.
Full check passes on x86-64.
This patch implements following evex512 version of string functions.
evex512 version takes up to 30% less cycle as compared to evex,
depending on length and alignment.
- memchr function using 512 bit vectors.
- rawmemchr function using 512 bit vectors.
- wmemchr function using 512 bit vectors.
Code size data:
memchr-evex.o 762 byte
memchr-evex512.o 576 byte (-24%)
rawmemchr-evex.o 461 byte
rawmemchr-evex512.o 412 byte (-11%)
wmemchr-evex.o 794 byte
wmemchr-evex512.o 552 byte (-30%)
Placeholder function, not used by any processor at the moment.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
In the future, this will result in a compilation failure if the
macros are unexpectedly undefined (due to header inclusion ordering
or header inclusion missing altogether).
Assembler sources are more difficult to convert. In many cases,
they are hand-optimized for the mangling and no-mangling variants,
which is why they are not converted.
sysdeps/s390/s390-32/__longjmp.c and sysdeps/s390/s390-64/__longjmp.c
are special: These are C sources, but most of the implementation is
in assembler, so the PTR_DEMANGLE macro has to be undefined in some
cases, to match the assembler style.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This allows us to define a generic no-op version of PTR_MANGLE and
PTR_DEMANGLE. In the future, we can use PTR_MANGLE and PTR_DEMANGLE
unconditionally in C sources, avoiding an unintended loss of hardening
due to missing include files or unlucky header inclusion ordering.
In i386 and x86_64, we can avoid a <tls.h> dependency in the C
code by using the computed constant from <tcb-offsets.h>. <sysdep.h>
no longer includes these definitions, so there is no cyclic dependency
anymore when computing the <tcb-offsets.h> constants.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This way, we can define the pointer guard macros without including
<sysdep.h> on x86-64. Other architectures will not have such an
inclusion dependency, and the implied header file inclusion would
create a porting hazard.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This works around a gcc issue where it const folded inf/inf into nan,
preventing the invalid exception to be signalled.
(x-x)/(x-x) is more robust against optimizations and works for all
out of bounds values including x==nan.
The gcc issue https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95115
should be fixed on release branches starting from gcc-10, but it is
better to change the code in case glibc is built with older gcc.
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
To avoid duplicate the VMM / GPR / mask insn macros in all incoming
evex512 files use the macros defined in 'reg-macros.h' and
'{vec}-macros.h'
This commit does not change libc.so
Tested build on x86-64
1) Copy so that backport will be easier.
2) Make section only define if there is not a previous definition
3) Add `VEC_lo` definition for proper reg-width but in the
ymm/zmm0-15 range.
4) Add macros for accessing GPRs based on VEC_SIZE
This is to make it easier to do think like:
```
vpcmpb %VEC(0), %VEC(1), %k0
kmov{d|q} %k0, %{eax|rax}
test %{eax|rax}
```
It adds macro s.t any GPR can get the proper width with:
`V{upcase_GPR_name}`
and any mask insn can get the proper width with:
`{upcase_mask_insn_without_postfix}`
This commit does not change libc.so
Tested build on x86-64
Besides the option being gcc specific, this approach is still fragile
and not future proof since we do not know if this will be the only
optimization option gcc will add that transforms loops to memset
(or any libcall).
This patch adds a new header, dl-symbol-redir-ifunc.h, that can b
used to redirect the compiler generated libcalls to port the generic
memset implementation if required.
Checked on x86_64-linux-gnu and aarch64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
A start.o compiled from start.S with -DPIC and no -DSHARED is used by
both crt1.o and rcrt1.o. So the LoongArch static PIE patch
unintentionally introduced PC-relative addressing for main and
__libc_start_main into crt1.o.
While the latest Binutils (trunk, which will be released as 2.40)
supports the PC-relative relocs against an external function by creating
a PLT entry, the 2.39 release branch doesn't (and won't) support this.
An error is raised:
"PLT stub does not represent and symbol not defined."
So, we need the following changes:
1. Check if ld supports the PC-relative relocs against an external
function. If it's not supported, we deem static PIE unsupported.
2. Change start.S. If static PIE is supported, use PC-relative
addressing for main and __libc_start_main and rely on the linker to
create PLT entries. Otherwise, restore the old behavior (using GOT
to address these functions).
An alternative would be adding a new "static-pie-start.S", and some
custom logic into Makefile to build rcrt1.o with it. And, restore
start.S to the state before static PIE change so crt1.o won't contain
PC-relative relocs against external symbols. But I can't see any
benefit of this alternative, so I'd just keep it simple.
Tested by building glibc with the following configurations:
1. Binutils trunk + GCC trunk. Static PIE enabled. All tests
passed.
2. Binutils 2.39 branch + GCC trunk. Static PIE disabled. Tests
related to ifunc failed (it's a known issue). All other tests
passed.
3. Binutils 2.39 branch + GCC 12 branch, cross compilation with
build-many-glibcs.py from x86_64-linux-gnu. Static PIE disabled.
Build succeeded.
As per other architectures. I have checked on a armv8 hardware with
the following configurations:
arm-linux-gnueabihf (gcc built with --with-float=hard --with-cpu=arm926ej-s)
armv5-linux-gnueabihf (-march=armv5te -mfpu=vfpv3)
armv7-linux-gnueabihf (-march=armv7-a -mfpu=vfpv3)
armv7-thumb-linux-gnueabihf (-march=armv7-a -mfpu=vfpv3 -mthumb)
armv7-neon-linux-gnueabihf (-march=armv7-a -mfpu=neon)
armv7-neonhard-linux-gnueabihf (-march=armv7-a -mfpu=neon -mfloat-abi=hard)
Without any regression.
I haven't dig into the code, but since Linux atomic-machine.h handle
pre-ARMv6 and ARMv6 I expect the compiler might have some small room
to optimize.
The code size also improves is most of the configurations:
* master
text data bss dec hex filename
1727801 9720 37928 1775449 1b1759 arm-linux-gnueabihf/libc.so
1691729 9720 37928 1739377 1a8a71 arm-linux-gnueabihf-armv7-disable-multi-arch/libc.so
1725509 9720 37928 1773157 1b0e65 armv5-linux-gnueabihf/libc.so
1700757 9720 37928 1748405 1aadb5 armv6-linux-gnueabihf/libc.so
1698973 9720 37928 1746621 1aa6bd armv6t2-linux-gnueabihf/libc.so
1695481 9752 37928 1743161 1a9939 armv7-linux-gnueabihf/libc.so
1692917 9744 37928 1740589 1a8f2d armv7-neonhard-linux-gnueabihf/libc.so
1692917 9744 37928 1740589 1a8f2d armv7-neon-linux-gnueabihf/libc.so
1225353 9752 37928 1273033 136cc9 armv7-thumb-linux-gnueabihf/libc.so
* patched
text data bss dec hex filename
1726805 9720 37928 1774453 1b1375 arm-linux-gnueabihf/libc.so
1689321 9720 37928 1736969 1a8109 arm-linux-gnueabihf-armv7-disable-multi-arch/libc.so
1724433 9720 37928 1772081 1b0a31 armv5-linux-gnueabihf/libc.so
1698301 9720 37928 1745949 1aa41d armv6-linux-gnueabihf/libc.so
1696525 9720 37928 1744173 1a9d2d armv6t2-linux-gnueabihf/libc.so
1693009 9752 37928 1740689 1a8f91 armv7-linux-gnueabihf/libc.so
1690493 9744 37928 1738165 1a85b5 armv7-neonhard-linux-gnueabihf/libc.so
1690493 9744 37928 1738165 1a85b5 armv7-neon-linux-gnueabihf/libc.so
1223837 9752 37928 1271517 1366dd armv7-thumb-linux-gnueabihf/libc.so
The idea is eventually move all architectures to use compiler builtins.
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Tested-by: Aurelien Jarno <aurelien@aurel32.net>
Removal of legacy hwcaps support from the dynamic loader left
no users of _dl_string_hwcap.
Signed-off-by: Javier Pello <devel@otheo.eu>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Last commit made it so that the value passed for that parameter was
always 0 at its only call site.
Signed-off-by: Javier Pello <devel@otheo.eu>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
This was to test loading of shared libraries from platform
subdirectories, but this functionality is going away in the
following commits.
Signed-off-by: Javier Pello <devel@otheo.eu>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
This patch updates the kernel version in the tests tst-mman-consts.py,
tst-mount-consts.py and tst-pidfd-consts.py to 6.0. (There are no new
constants covered by these tests in 6.0 that need any other header
changes.)
Tested with build-many-glibcs.py.
The compiler might transform __stpcpy calls (which are routed to
__builtin_stpcpy as an optimization) to strcpy and x86_64 strcpy
multiarch implementation does not build any working symbol due
ISA_SHOULD_BUILD not being evaluated for IS_IN(rtld).
Checked on x86_64-linux-gnu.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
This addition to the list of source headers in
sysdeps/mach/hurd/bits/errno.h appears in the source tree after
build-many-glibcs.py runs, I'm guessing resulting from gnumach commit
c566ad85a2d6728ebc8ec0f461a3b35df300e96e.
Linux 6.0 has no new syscalls. Update the version number in
syscall-names.list to reflect that it is still current for 6.0.
Tested with build-many-glibcs.py.
The AVX2 strrchr and wcsrchr implementation uses the 'blsmsk'
instruction which belongs to the BMI1 CPU feature and the 'shrx'
instruction, which belongs to the BMI2 CPU feature.
Fixes: df7e295d18 ("x86: Optimize {str|wcs}rchr-avx2")
Partially resolves: BZ #29611
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
The AVX2 memrchr implementation uses the 'shlxl' instruction, which
belongs to the BMI2 CPU feature and uses the 'lzcnt' instruction, which
belongs to the LZCNT CPU feature.
Fixes: af5306a735 ("x86: Optimize memrchr-avx2.S")
Partially resolves: BZ #29611
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
The AVX2 memchr, rawmemchr and wmemchr implementations use the 'bzhi'
and 'sarx' instructions, which belongs to the BMI2 CPU feature.
Fixes: acfd088a19 ("x86: Optimize memchr-avx2.S")
Partially resolves: BZ #29611
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
The AVX2 wcs(n)cmp implementations use the 'bzhi' instruction, which
belongs to the BMI2 CPU feature.
NB: It also uses the 'tzcnt' BMI1 instruction, but it is executed as BSF
as BSF if the CPU doesn't support TZCNT, and produces the same result
for non-zero input.
Partially fixes: b77b06e0e2 ("x86: Optimize strcmp-avx2.S")
Partially resolves: BZ #29611
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
The AVX2 strncmp implementations uses the 'bzhi' instruction, which
belongs to the BMI2 CPU feature.
NB: It also uses the 'tzcnt' BMI1 instruction, but it is executed as BSF
as BSF if the CPU doesn't support TZCNT, and produces the same result
for non-zero input.
Partially fixes: b77b06e0e2 ("x86: Optimize strcmp-avx2.S")
Partially resolves: BZ #29611
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
The AVX2 strcmp implementation uses the 'bzhi' instruction, which
belongs to the BMI2 CPU feature.
NB: It also uses the 'tzcnt' BMI1 instruction, but it is executed as BSF
as BSF if the CPU doesn't support TZCNT, and produces the same result
for non-zero input.
Partially fixes: b77b06e0e2 ("x86: Optimize strcmp-avx2.S")
Partially resolves: BZ #29611
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
The AVX2 str(n)casecmp implementations use the 'bzhi' instruction, which
belongs to the BMI2 CPU feature.
NB: It also uses the 'tzcnt' BMI1 instruction, but it is executed as BSF
as BSF if the CPU doesn't support TZCNT, and produces the same result
for non-zero input.
Partially fixes: b77b06e0e2 ("x86: Optimize strcmp-avx2.S")
Partially resolves: BZ #29611
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
The "System V Application Binary Interface AMD64 Architecture Processor
Supplement" mandates the BMI1 and BMI2 CPU features for the x86-64-v3
level.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
Save a jmp on the lock path coming from an initial failure in
pthread_spin_lock.S. This costs 4-bytes of code but since the
function still fits in the same number of 16-byte blocks (default
function alignment) it does not have affect on the total binary size
of libc.so (unchanged after this commit).
pthread_spin_trylock was using a CAS when a simple xchg works which
is often more expensive.
Full check passes on x86-64.
After upgrading glibc to Debian 2.35-1, gdb faulted on
startup and dropped core in a function call in the main
application. This was caused by not initializing the
global dp register for the main application early enough.
Restore the code to initialize dp in _dl_start_user.
It was removed when code was added to initialize dp in
elf_machine_runtime_setup.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Use INTERNAL_SYSCALL_CALL instead of INLINE_SYSCALL_CALL. This
requires emulate the semantic for hurd call (so __arc4random_buf
uses the fallback).
Checked on x86_64-linux-gnu.
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
Using an unsigned type prevents the fallback to be used if kernel
does not support getrandom syscall.
Checked on x86_64-linux-gnu.
Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
If the compiler is new enough, enable static PIE support. In the static
PIE version of _start (in rcrt1.o), use la.pcrel instead of la.got
because in a static PIE we cannot use GOT entries until the dynamic
relocations for GOT are resolved.
Previous implementation was adjusting length (rsi) to match
bytes (eax), but since there is no bound to length this can cause
overflow.
Fix is to just convert the byte-count (eax) to length by dividing by
sizeof (wchar_t) before the comparison.
Full check passes on x86-64 and build succeeds w/ and w/o multiarch.
GCC 13 adds support for _FloatN and _FloatNx types in C++, so breaking
the installed glibc headers that assume such support is not present.
GCC mostly works around this with fixincludes, but that doesn't help
for building glibc and its tests (glibc doesn't itself contain C++
code, but there's C++ code built for tests). Update glibc's
bits/floatn-common.h and bits/floatn.h headers to handle the GCC 13
support directly.
In general the changes match those made by fixincludes, though I think
the ones in sysdeps/powerpc/bits/floatn.h, where the header tests
__LDBL_MANT_DIG__ == 113 or uses #elif, wouldn't match the existing
fixincludes patterns.
Some places involving special C++ handling in relation to _FloatN
support are not changed. There's no need to change the
__HAVE_FLOATN_NOT_TYPEDEF definition (also in a form that wouldn't be
matched by the fixincludes fixes) because it's only used in relation
to macro definitions using features not supported for C++
(__builtin_types_compatible_p and _Generic). And there's no need to
change the inline function overloads for issignaling, iszero and
iscanonical in C++ because cases where types have the same format but
are no longer compatible types are handled automatically by the C++
overload resolution rules.
This patch also does not change the overload handling for iseqsig, and
there I think changes *are* needed, beyond those in this patch or made
by fixincludes. The way that overload is defined, via a template
parameter to a structure type, requires overloads whenever the types
are incompatible, even if they have the same format. So I think we
need to add overloads with GCC 13 for every supported _FloatN and
_FloatNx type, rather than just having one for _Float128 when it has a
different ABI to long double as at present (but for older GCC, such
overloads must not be defined for types that end up defined as
typedefs for another type).
Tested with build-many-glibcs.py: compilers build for
aarch64-linux-gnu ia64-linux-gnu mips64-linux-gnu powerpc-linux-gnu
powerpc64le-linux-gnu x86_64-linux-gnu; glibcs build for
aarch64-linux-gnu ia64-linux-gnu i686-linux-gnu mips-linux-gnu
mips64-linux-gnu-n32 powerpc-linux-gnu powerpc64le-linux-gnu
x86_64-linux-gnu.
Fix the subscript on air->family, which was accidentally set to COUNT
when it should have remained as I.
Resolves: BZ #29605
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Rename atomic_exchange_rel/acq to use atomic_exchange_release/acquire
since these map to the standard C11 atomic builtins.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Replace atomic_decrement_and_test with atomic_fetch_add_relaxed.
These are simple counters which do not protect any shared data from
concurrent accesses. Also remove the unused file cond-perf.c.
Passes regress on AArch64.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Replace atomic_increment and atomic_increment_val with atomic_fetch_add_relaxed.
One case in sem_post.c uses release semantics (see comment above it).
The others are simple counters and do not protect any shared data from
concurrent accesses.
Passes regress on AArch64.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
We don't need RV32 specific floating point functions, instead make them
generic for RISC-V.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Both RV32 and RV64 should have the same libm-test-ulps, so consolidate
them into a single file.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
QEMU does not support support set_robust_list. Thus, we need
to enable detection of set_robust_list system call.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
It avoid a possible compiler warning where right size of operator
is converted from a negative value to unsigned.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
A new internal definition, __LIBC_LOCK_ALIGNMENT, is used to force
the 4-byte alignment only for m68k, other architecture keep the
natural alignment of the type used internally (and hppa does not
require 16-byte alignment for kernel-assisted CAS).
Reviewed-by: Florian Weimer <fweimer@redhat.com>
POSIX does not say this value is special. For example, old XFS file
systems may still use inode number zero.
Also update the comment regarding ENOENT. Linux may return ENOENT
for some file systems.
Non-at functions can be implemented by just calling the corresponding at
function with AT_FDCWD and zero at_flags.
In the linkat case, the at behavior is different (O_NOLINK), so this introduces
__linkat_common to pass O_NOLINK as appropriate.
lstat functions can also be implemented with fstatat by adding
__fstatat64_common which takes a flags parameter in addition to the at_flags
parameter,
In the end this factorizes chmod, chown, link, lstat64, mkdir, readlink,
rename, stat64, symlink, unlink, utimes.
This also makes __lstat, __lxstat64, __stat and __xstat64 directly use
__fstatat64_common instead of __lstat64 or __stat64.
__syscall_error may end up farther than 1MiB away from a caller,
especially when linking statically large binaries. tail allows for
4GiB jumps and is reduced to j when a linked symbol is within range.
Fixes: 36960f0c76 ("RISC-V: Linux Syscall Interface")
Fixes: 7f33b09c65 ("RISC-V: Linux ABI")
Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
9e5c991106 ("hurd: Fix readlink() hanging on fifo") separated opening
the file for the stat call from opening the file for the read call. That
however opened a small window for the file to change. Better make this
atomic by reopening the file with O_READ.
readlink() opens the target with O_READ to be able to read the symlink
content. When the target is actually a fifo, that would hang waiting for a
writer (caught in the coreutils testsuite). We thus have to first lookup the
target without O_READ to perform io_stat and lookout for fifos, and only
after checking the symlink type, we can re-lookup with O_READ.
Replace the 3 uses of atomic_bit_set and atomic_bit_test_set with
atomic_fetch_or_relaxed. Using relaxed MO is correct since the
atomics are used to ensure memory is released only once.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
Some architectures (mips, powerpc and sparc) define separate values for
EDEADLOCK and EDEADLK. Readd the errlist entry for EDEADLOCK for those
configurations. Also use the dependency files from generating the
auxiliary errlist and siglist files.
C2x makes static_assert and thread_local into keywords, removing the
definitions as macros in assert.h and threads.h. Thus, disable those
macros in those glibc headers for C2x.
The disabling is done based on a combination of language version and
__GNUC_PREREQ, *not* based on __GLIBC_USE (ISOC2X), on the principle
that users of the header (when requesting C11 or later APIs - not
assert.h for C99 and older API versions) should always have the names
static_assert or thread_local available after inclusion of the header,
whether as a keyword or as a macro. Thus, when using a compiler
without the keywords (whether an older compiler, possibly in C2x mode,
or _GNU_SOURCE with any compiler but in an older language mode, for
example) the macros should be defined, even when C2x APIs have been
requested. The __GNUC_PREREQ conditionals here may well need updating
with the versions of other compilers that gained support for these
keywords in C2x mode.
Tested for x86_64.
Not all compilers support the inline asm prefix '%v' to emit the avx
instruction if AVX is enable. Use a prefix instead.
Checked on x86_64-linux-gnu and i686-linux-gnu.
It avoids the possible warning of uninitialized 'frame' variable when
building with clang:
../sysdeps/nptl/jmp-unwind.c:27:42: error: variable 'frame' is
uninitialized when used here [-Werror,-Wuninitialized]
__pthread_cleanup_upto (env->__jmpbuf, CURRENT_STACK_FRAME);
The resulting code is similar to CURRENT_STACK_FRAME.
Checked on x86_64-linux-gnu.
On s390x syscalls are triggered by svc instruction. One can
pass the syscall number encoded in the instruction "svc 123"
or by storing it in r1:
lghi r1,123
svc 0
If the syscall number is encoded in the instruction, this can
cause broken syscall restarts. Therefore this patch is now just
passing the syscall number in r1.
See also kernel-commit:
"s390/signal: switch to using vdso for sigreturn and syscall restart"
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/arch/s390/[%e2%80%a6]call.c?h=v6.0-rc1&id=df29a7440c4b5c65765c8f60396b3b13063e24e9
As information, the "svc 0" feature was introduced in kernel 2.5.62:
commit b5aad611393ef2e132e3648fa4c6e56a9cfa8708
GCC 13 compiles these built-ins to {fmax,fmin}.{s/d} instruction, use
them instead of the generic implementation.
Link: https://gcc.gnu.org/r13-2085
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
We should default to the larger code model, in order to support
larger applications built with -static -pie. This should be
consistent with pic-ccflag, which defaults to -fPIC.
Remove the now redundant override from sysdeps/sparc/Makefile.
Note that -fno-pie and -fno-PIE have the same effect.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
In gnumach, 3e1702a65fb3 ("add rpc_versions for vm types") changed the type
of vm_size_t, making it always a unsigned long. This made it incompatible on
x86 with size_t. Even if we may want to revert it to unsigned int, it's
better to fix the types of parameters according to the .defs files.
posix advises to have strerror_r fill a message even when we are returning
an error.
This makes mach's xpg_strerror_r do this, like the generic version does.
Spotted by the libunistring testsuite test-strerror_r
08d2024b41 ("string: Simplify strerror_r") inadvertently made
__strerror_r print unknown error system in decimal while the original
code was printing it in hexadecimal. perror was kept printing in
hexadecimal in 725eeb4af1 ("string: Use tls-internal on strerror_l"),
let us keep both coherent.
This also fixes a duplicate ':'
Spotted by the libunistring testsuite test-perror2
The start code can get linked into dynamic linked executables where
LGPL would require shipping the source or linkable binaries when the
executable is distributed.
On some targets the license exception was missing in start.S (which
is compiled into crt1.o and Scrt1.o which may end up linked into PDE
and PIE binaries).
I did not review what other code may end up in executables, just
fixed the start.S license inconsistency across targets.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Changes to these arrays are often backported to stable releases,
but additions to these arrays shift the offsets of the following
_rltd_global_ro members, thus breaking the GLIBC_PRIVATE ABI.
Obviously, this change is itself an internal ABI break, but at least
it will avoid further ABI breaks going forward.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
This reverts commit 6f85dbf102.
Once this change hits the release branches, it will require relinking
of all statically linked applications before static dlopen works
again, for the majority of updates on release branches: The NEWS file
is regularly updated with bug references, so the __libc_early_init
suffix changes, and static dlopen cannot find the function anymore.
While this ABI check is still technically correct (we do require
rebuilding & relinking after glibc updates to keep static dlopen
working), it is too drastic for stable release branches.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
The files NEWS, include/link.h, and sysdeps/generic/ldsodefs.h
contribute to the version fingerprint used for detection. The
fingerprint can be further refined using the --with-extra-version-id
configure argument.
_dl_call_libc_early_init is replaced with _dl_lookup_libc_early_init.
The new function is used store a pointer to libc.so's
__libc_early_init function in the libc_map_early_init member of the
ld.so namespace structure. This function pointer can then be called
directly, so the separate invocation function is no longer needed.
The versioned symbol lookup needs the symbol versioning data
structures, so the initialization of libc_map and libc_map_early_init
is now done from _dl_check_map_versions, after this information
becomes available. (_dl_map_object_from_fd does not set this up
in time, so the initialization code had to be moved from there.)
This means that the separate initialization code can be removed from
dl_main because _dl_check_map_versions covers all maps, including
the initial executable loaded by the kernel. The lookup still happens
before relocation and the invocation of IFUNC resolvers, so IFUNC
resolvers are protected from ABI mismatch.
The __libc_early_init function pointer is not protected because
so little code runs between the pointer write and the invocation
(only dynamic linker code and IFUNC resolvers).
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* posix/getopt.c (_getopt_initialize):
* sysdeps/posix/tempname.c (try_dir, try_nocreate):
Put _GL_UNUSED before args instead of after.
This makes no difference for glibc.
It is needed for Gnulib when being compiled on
non-GCC C23 compilers.
gcc introduces gs:0x14 accesses in most functions, so we need some tcbhead
to be ready very early during initialization. This configures a static area
which can be referenced by various protected functions, until proper TLS is
set up.
Linux 5.19 adds more HWCAP2_* values for AArch64; add these to its
bits/hwcap.h header in glibc.
Tested with build-many-glibcs.py for aarch64-linux-gnu.
Linux 5.19 adds a new accounting flag AGROUP; add it to the
enumeration in sys/acct.h.
This shows up that the Alpha-specific variant of this header has a
different set of constants and struct acct, which appear to be the
constants and structure layout from Linux 2.0. These were changed
some time between Linux 2.0 and Linux 2.2; I see no evidence of an
Alpha-specific layout or set of constants, but haven't checked the
detailed Linux kernel history between those versions. Rather, it
looks like tha Alpha-specific header was originally needed because of
the use of types in the kernel structure (such as uid_t and gid_t)
that had different sizes on Alpha, and when glibc was updated for
changes to the structure and constants in the kernel
1998-10-02 Andreas Jaeger <aj@arthur.rhein-neckar.de>
* sysdeps/unix/sysv/linux/sys/acct.h: Bring in sync with current
linux 2.1 version.
that simply omitted to do anything about the Alpha version.
Thus, remove the Alpha version in order to get the updated definitions
into use on Alpha, as I don't think the interfaces are actually
different for Alpha with any kernel version supported by glibc.
Tested for x86_64, and with build-many-glibcs.py for alpha-linux-gnu.
The kernel special-cases the zero argument for alpha brk, and we can
use that to restore the generic Linux error handling behavior.
Fixes commit b57ab258c1 ("Linux:
Introduce __brk_call for invoking the brk system call").
We do not have a hurd data block only when bootstrapping the system, in
which case we don't have a notion of suid yet anyway.
This is needed, otherwise init_standard_fds would check that standard
file descriptors are allocated, which is meaningless during bootstrap.
If the architecture level set is high enough, no IFUNCs are used at
all and the variable i would be unused. Then the build fails with:
../sysdeps/s390/multiarch/ifunc-impl-list.c: In function ‘__libc_ifunc_impl_list’:
../sysdeps/s390/multiarch/ifunc-impl-list.c:76:10: error: unused variable ‘i’ [-Werror=unused-variable]
76 | size_t i = max;
| ^
cc1: all warnings being treated as errors
math/test-float128-y1 fails on x86_64 and ppc64el with gcc 12 and -O3,
because code inside a block guarded by SET_RESTORE_ROUNDL is being moved
after the rounding mode has been restored. Use math_force_eval to
prevent this (and insert some math_opt_barrier calls to prevent code
from being moved before the rounding mode is set).
Fixes#29463
Reviewed-By: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
The #ifdef FSOPEN_CLOEXEC check did not work because the macro
was always defined in this header prior to the check, so that
the <linux/mount.h> contents did not matter.
Fixes commit 774058d729
("linux: Fix sys/mount.h usage with kernel headers").
I.e. from sysdeps/unix/sysv/linux/bits/in.h to netinet/in.h
It is following both the BSD and Linux definitions.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
Now that kernel exports linux/mount.h and includes it on linux/fs.h,
its definitions might clash with glibc exports sys/mount.h. To avoid
the need to rearrange the Linux header to be always after glibc one,
the glibc sys/mount.h is changed to:
1. Undefine the macros also used as enum constants. This covers prior
inclusion of <linux/mount.h> (for instance MS_RDONLY).
2. Include <linux/mount.h> based on the usual __has_include check
(needs to use __has_include ("linux/mount.h") to paper over GCC
bugs.
3. Define enum fsconfig_command only if FSOPEN_CLOEXEC is not defined.
(FSOPEN_CLOEXEC should be a very close proxy.)
4. Define struct mount_attr if MOUNT_ATTR_SIZE_VER0 is not defined.
(Added in the same commit on the Linux side.)
This patch also adds some tests to check if including linux/fs.h and
linux/mount.h after and before sys/mount.h does work.
Checked on x86_64-linux-gnu.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
Improve performance of recursive IO locks by adding a fast path for
the single-threaded case. To reduce the number of memory accesses for
locking/unlocking, only increment the recursion counter if the lock
is already taken.
On Neoverse V1, a microbenchmark with many small freads improved by
2.9x. Multithreaded performance improved by 2%.
Reviewed-by: Cristian Rodríguez <crrodriguez@opensuse.org>
So far this test checks if pidfd_open-syscall is supported,
which was introduced with linux 5.3.
The process_madvise-syscall was introduced with linux 5.10.
Thus you'll get FAILs if you are running a kernel in between.
This patch adds a check if the first process_madvise-syscall
returns ENOSYS and in this case will fail with UNSUPPORTED.
Reviewed-by: Florian Weimer <fweimer@redhat.com>
`#ifndef STPCPY` is incorrect for checking if `STRCPY` is already
defined. It doesn't end up mattering as the whole check is
guarded by `#if IS_IN (libc)` but is incorrect none the less.
Similar to 6720d36b66 for x86-64.
Clang cannot assemble movzx in the AT&T dialect mode. Change movzx to
movzbl, which follows the AT&T dialect and is used elsewhere in the
file.
The older libc versions are obsolete for over twenty years now.
This patch removes the special flags for libc5 and libc4 and assumes
that all libraries cached are libc6 compatible and use FLAG_ELF_LIBC6.
Checked with a build for all affected architectures.
Co-authored-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
exit only terminates the current thread, not the whole process, so it
is the wrong fallback system call in this context. All supported
Linux versions implement the exit_group system call anyway.
This patch updates the kernel version in the tests tst-mman-consts.py,
tst-mount-consts.py and tst-pidfd-consts.py to 5.18. (There are no
new constants covered by these tests in 5.19, or in 5.17 or 5.18 in
the case of tst-mount-consts.py that previously used version 5.16,
that need any other header changes.)
Tested with build-many-glibcs.py.
__pthread_sigmask cannot actually fail with valid pointer arguments
(it would need a really broken seccomp filter), and we do not check
for errors elsewhere.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Since commit ec2c1fcefb ("malloc:
Abort on heap corruption, without a backtrace [BZ #21754]"),
__libc_message always terminates the process. Since commit
a289ea09ea ("Do not print backtraces
on fatal glibc errors"), the backtrace facility has been removed.
Therefore, remove enum __libc_message_action and the action
argument of __libc_message, and mark __libc_message as _No_return.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Linux 5.19 has no new syscalls, but enables memfd_secret in the uapi
headers for RISC-V. Update the version number in syscall-names.list
to reflect that it is still current for 5.19 and regenerate the
arch-syscall.h headers with build-many-glibcs.py update-syscalls.
Tested with build-many-glibcs.py.
The inline and library functions that the CMSG_NXTHDR macro may expand
to increment the pointer to the header before checking the stride of
the increment against available space. Since C only allows incrementing
pointers to one past the end of an array, the increment must be done
after a length check. This commit fixes that and includes a regression
test for CMSG_FIRSTHDR and CMSG_NXTHDR.
The Linux, Hurd, and generic headers are all changed.
Tested on Linux on armv7hl, i686, x86_64, aarch64, ppc64le, and s390x.
[BZ #28846]
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
pidfd_getfd can fail for a valid pidfd with errno EPERM for various
reasons in a restricted environment. Use FAIL_UNSUPPORTED in that case.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Rather than buffering 16 MiB of entropy in userspace (by way of
chacha20), simply call getrandom() every time.
This approach is doubtlessly slower, for now, but trying to prematurely
optimize arc4random appears to be leading toward all sorts of nasty
properties and gotchas. Instead, this patch takes a much more
conservative approach. The interface is added as a basic loop wrapper
around getrandom(), and then later, the kernel and libc together can
work together on optimizing that.
This prevents numerous issues in which userspace is unaware of when it
really must throw away its buffer, since we avoid buffering all
together. Future improvements may include userspace learning more from
the kernel about when to do that, which might make these sorts of
chacha20-based optimizations more possible. The current heuristic of 16
MiB is meaningless garbage that doesn't correspond to anything the
kernel might know about. So for now, let's just do something
conservative that we know is correct and won't lead to cryptographic
issues for users of this function.
This patch might be considered along the lines of, "optimization is the
root of all evil," in that the much more complex implementation it
replaces moves too fast without considering security implications,
whereas the incremental approach done here is a much safer way of going
about things. Once this lands, we can take our time in optimizing this
properly using new interplay between the kernel and userspace.
getrandom(0) is used, since that's the one that ensures the bytes
returned are cryptographically secure. But on systems without it, we
fallback to using /dev/urandom. This is unfortunate because it means
opening a file descriptor, but there's not much of a choice. Secondly,
as part of the fallback, in order to get more or less the same
properties of getrandom(0), we poll on /dev/random, and if the poll
succeeds at least once, then we assume the RNG is initialized. This is a
rough approximation, as the ancient "non-blocking pool" initialized
after the "blocking pool", not before, and it may not port back to all
ancient kernels, though it does to all kernels supported by glibc
(≥3.2), so generally it's the best approximation we can do.
The motivation for including arc4random, in the first place, is to have
source-level compatibility with existing code. That means this patch
doesn't attempt to litigate the interface itself. It does, however,
choose a conservative approach for implementing it.
Cc: Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Cristian Rodríguez <crrodriguez@opensuse.org>
Cc: Paul Eggert <eggert@cs.ucla.edu>
Cc: Mark Harris <mark.hsj@gmail.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: linux-crypto@vger.kernel.org
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
