Commit Graph

2813 Commits

Author SHA1 Message Date
H.J. Lu
42e48e720c nptl: Add tst-pthread-key1-static for BZ #21777
Add a static pthread static tests to verify that BZ #21777 is fixed.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2024-04-09 05:27:03 -07:00
Konstantin Kharlamov
fe00366b63 treewide: python-scripts: use is None for none-equality
Testing for `None`-ness with `==` operator is frowned upon and causes
warnings in at least "LGTM" python linter. Fix that.

Signed-off-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2024-02-23 08:50:00 -03:00
Adhemerval Zanella
460860f457 Remove ia64-linux-gnu
Linux 6.7 removed ia64 from the official tree [1], following the general
principle that a glibc port needs upstream support for the architecture
in all the components it depends on (binutils, GCC, and the Linux
kernel).

Apart from the removal of sysdeps/ia64 and sysdeps/unix/sysv/linux/ia64,
there are updates to various comments referencing ia64 for which removal
of those references seemed appropriate. The configuration is removed
from README and build-many-glibcs.py.

The CONTRIBUTED-BY, elf/elf.h, manual/contrib.texi (the porting
mention), *.po files, config.guess, and longlong.h are not changed.

For Linux it allows cleanup some clone2 support on multiple files.

The following bug can be closed as WONTFIX: BZ 22634 [2], BZ 14250 [3],
BZ 21634 [4], BZ 10163 [5], BZ 16401 [6], and BZ 11585 [7].

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=43ff221426d33db909f7159fdf620c3b052e2d1c
[2] https://sourceware.org/bugzilla/show_bug.cgi?id=22634
[3] https://sourceware.org/bugzilla/show_bug.cgi?id=14250
[4] https://sourceware.org/bugzilla/show_bug.cgi?id=21634
[5] https://sourceware.org/bugzilla/show_bug.cgi?id=10163
[6] https://sourceware.org/bugzilla/show_bug.cgi?id=16401
[7] https://sourceware.org/bugzilla/show_bug.cgi?id=11585
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2024-01-08 17:09:36 -03:00
Paul Eggert
dff8da6b3e Update copyright dates with scripts/update-copyrights 2024-01-01 10:53:40 -08:00
Florian Weimer
e21aa9b9cc nptl: Link tst-execstack-threads-mod.so with -z execstack
This ensures that the test still links with a linker that refuses
to create an executable stack marker automatically.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2023-11-20 09:22:25 +01:00
Florian Weimer
8c8eff33e4 nptl: Rename tst-execstack to tst-execstack-threads
So that the test is harder to confuse with elf/tst-execstack
(although the tests are supposed to be the same).

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2023-11-20 09:22:21 +01:00
Adhemerval Zanella
fee9e40a8d malloc: Decorate malloc maps
Add anonymous mmap annotations on loader malloc, malloc when it
allocates memory with mmap, and on malloc arena.  The /proc/self/maps
will now print:

   [anon: glibc: malloc arena]
   [anon: glibc: malloc]
   [anon: glibc: loader malloc]

On arena allocation, glibc annotates only the read/write mapping.

Checked on x86_64-linux-gnu and aarch64-linux-gnu.
Reviewed-by: DJ Delorie <dj@redhat.com>
2023-11-07 10:27:20 -03:00
Adhemerval Zanella
6afce56c19 nptl: Decorate thread stack on pthread_create
Linux 4.5 removed thread stack annotations due to the complexity of
computing them [1], and Linux added PR_SET_VMA_ANON_NAME on 5.17
as a way to name anonymous virtual memory areas.

This patch adds decoration on the stack created and used by
pthread_create, for glibc crated thread stack the /proc/self/maps will
now show:

  [anon: glibc: pthread stack: <tid>]

And for user-provided stacks:

  [anon: glibc: pthread user stack: <tid>]

The guard page is not decorated, and the mapping name is cleared when
the thread finishes its execution (so the cached stack does not have any
name associated).

Checked on x86_64-linux-gnu aarch64 aarch64-linux-gnu.

[1] 65376df582

Co-authored-by: Ian Rogers <irogers@google.com>
Reviewed-by: DJ Delorie <dj@redhat.com>
2023-11-07 10:27:20 -03:00
Samuel Thibault
6333a6014f __call_tls_dtors: Use call_function_static_weak 2023-09-04 20:03:37 +02:00
Florian Weimer
2c6b4b272e nptl: Unconditionally use a 32-byte rseq area
If the kernel headers provide a larger struct rseq, we used that
size as the argument to the rseq system call.  As a result,
rseq registration would fail on older kernels which only accept
size 32.
2023-07-21 16:18:18 +02:00
Arsen Arsenović
3edca7f545
nptl: Make tst-tls3mod.so explicitly lazy
Fixes the following test-time errors, that lead to FAILs, on toolchains
that set -z now out o the box, such as the one used on Gentoo Hardened:

  .../build-x86-x86_64-pc-linux-gnu-nptl $ grep '' nptl/tst-tls3*.out
  nptl/tst-tls3.out:dlopen failed
  nptl/tst-tls3-malloc.out:dlopen failed

Reviewed-by: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Andreas K. Hüttel <dilfridge@gentoo.org>
2023-07-20 12:24:28 +02:00
Paul Eggert
3edc4ff2ce make ‘struct pthread’ a complete type
* nptl/descr.h (struct pthread): Remove end_padding member, which
made this type incomplete.
(PTHREAD_STRUCT_END_PADDING): Stop using end_padding.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-07-19 14:16:04 -07:00
Frédéric Bérat
8022fc7d51 tests: replace system by xsystem
With fortification enabled, system calls return result needs to be checked,
has it gets the __wur macro enabled.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-06-19 09:15:05 -04:00
Frédéric Bérat
20b6b8e8a5 tests: replace read by xread
With fortification enabled, read calls return result needs to be checked,
has it gets the __wur macro enabled.

Note on read call removal from  sysdeps/pthread/tst-cancel20.c and
sysdeps/pthread/tst-cancel21.c:
It is assumed that this second read call was there to overcome the race
condition between pipe closure and thread cancellation that could happen
in the original code. Since this race condition got fixed by
d0e3ffb7a5 the second call seems
superfluous. Hence, instead of checking for the return value of read, it
looks reasonable to simply remove it.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-06-19 09:14:56 -04:00
Paul Pluzhnikov
7f0d9e61f4 Fix all the remaining misspellings -- BZ 25337 2023-06-02 01:39:48 +00:00
Frédéric Bérat
026a84a54d tests: replace write by xwrite
Using write without cheks leads to warn unused result when __wur is
enabled.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
2023-06-01 12:40:05 -04:00
Carlos O'Donell
b600f47758 nptl: Reformat Makefile.
Reflow all long lines adding comment terminators.
Rename files that cause inconsistent ordering.
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.
2023-05-18 12:39:47 -04:00
Cupertino Miranda
b630be0922 Created tunable to force small pages on stack allocation.
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>
2023-04-20 13:54:24 -03:00
Adhemerval Zanella Netto
33237fe83d Remove --enable-tunables configure option
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>
2023-03-29 14:33:06 -03:00
Adhemerval Zanella Netto
88677348b4 Move libc_freeres_ptrs and libc_subfreeres to hidden/weak functions
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>
2023-03-27 13:57:55 -03:00
Andreas Schwab
359a0b9dbc Remove pthread-pi-defines.sym
It became unused with the removal of the assembler implementation of the
pthread functions.
2023-02-03 17:59:55 +01:00
Joseph Myers
6d7e8eda9b Update copyright dates with scripts/update-copyrights 2023-01-06 21:14:39 +00:00
YunQiang Su
a9acb7b39e Define in_int32_t_range to check if the 64 bit time_t syscall should be used
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>
2022-11-17 14:35:13 -03:00
Florian Weimer
ee1ada1bdb elf: Rework exception handling in the dynamic loader [BZ #25486]
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>
2022-11-03 09:39:31 +01:00
Adhemerval Zanella
3d8b5dde87 nptl: Fix pthread_create.c build with clang
clang complains that libc_hidden_data_def (__nptl_threads_events)
creates an invalid alias:

  pthread_create.c:50:1: error: alias must point to a defined variable or function
  libc_hidden_data_def (__nptl_threads_events)
  ^
  ../include/libc-symbols.h:621:37: note: expanded from macro
  'libc_hidden_data_def'

It seems that clang requires that a proper prototype is defined prior
the hidden alias creation.

Reviewed-by: Fangrui Song <maskray@google.com>
2022-11-01 09:51:10 -03:00
Adhemerval Zanella
9b5e138f2b linux: Avoid shifting a negative signed on POSIX timer interface
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>
2022-10-20 10:19:08 -03:00
Yu Chien Peter Lin
365b3af67e nptl: Convert tst-setuid2 to test-driver
Use <support/test-driver.c> and replace pthread calls to its xpthread
equivalents.

Signed-off-by: Yu Chien Peter Lin <peterlin@andestech.com>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-10-03 11:19:36 -03:00
Wilco Dijkstra
22f4ab2d20 Use atomic_exchange_release/acquire
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>
2022-09-26 16:58:08 +01:00
Wilco Dijkstra
4a07fbb689 Use C11 atomics instead of atomic_decrement_and_test
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>
2022-09-23 15:59:56 +01:00
Wilco Dijkstra
d1babeb32d Use C11 atomics instead of atomic_increment(_val)
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>
2022-09-23 15:59:56 +01:00
Wilco Dijkstra
8114b95cef Use C11 atomics instead of atomic_and/or
Remove the 4 uses of atomic_and and atomic_or with atomic_fetch_and_acquire
and atomic_fetch_or_acquire. This is preserves existing implied semantics,
however relaxed MO on FUTEX_OWNER_DIED accesses may be correct.

Passes regress on AArch64.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
2022-09-23 15:59:56 +01:00
Adhemerval Zanella Netto
de477abcaa Use '%z' instead of '%Z' on printf functions
The Z modifier is a nonstandard synonymn for z (that predates z
itself) and compiler might issue an warning for in invalid
conversion specifier.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
2022-09-22 08:48:04 -03:00
Wilco Dijkstra
a30e960328 Use relaxed atomics since there is no MO dependence
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>
2022-09-13 11:58:07 +01:00
Wilco Dijkstra
a364a3a709 Use C11 atomics instead of atomic_decrement(_val)
Replace atomic_decrement and atomic_decrement_val with
atomic_fetch_add_relaxed.

Reviewed-by: DJ Delorie <dj@redhat.com>
2022-09-09 14:22:26 +01:00
Adhemerval Zanella Netto
6f4e0fcfa2 stdlib: Add arc4random, arc4random_buf, and arc4random_uniform (BZ #4417)
The implementation is based on scalar Chacha20 with per-thread cache.
It uses getrandom or /dev/urandom as fallback to get the initial entropy,
and reseeds the internal state on every 16MB of consumed buffer.

To improve performance and lower memory consumption the per-thread cache
is allocated lazily on first arc4random functions call, and if the
memory allocation fails getentropy or /dev/urandom is used as fallback.
The cache is also cleared on thread exit iff it was initialized (so if
arc4random is not called it is not touched).

Although it is lock-free, arc4random is still not async-signal-safe
(the per thread state is not updated atomically).

The ChaCha20 implementation is based on RFC8439 [1], omitting the final
XOR of the keystream with the plaintext because the plaintext is a
stream of zeros.  This strategy is similar to what OpenBSD arc4random
does.

The arc4random_uniform is based on previous work by Florian Weimer,
where the algorithm is based on Jérémie Lumbroso paper Optimal Discrete
Uniform Generation from Coin Flips, and Applications (2013) [2], who
credits Donald E. Knuth and Andrew C. Yao, The complexity of nonuniform
random number generation (1976), for solving the general case.

The main advantage of this method is the that the unit of randomness is not
the uniform random variable (uint32_t), but a random bit.  It optimizes the
internal buffer sampling by initially consuming a 32-bit random variable
and then sampling byte per byte.  Depending of the upper bound requested,
it might lead to better CPU utilization.

Checked on x86_64-linux-gnu, aarch64-linux, and powerpc64le-linux-gnu.

Co-authored-by: Florian Weimer <fweimer@redhat.com>
Reviewed-by: Yann Droneaud <ydroneaud@opteya.com>

[1] https://datatracker.ietf.org/doc/html/rfc8439
[2] https://arxiv.org/pdf/1304.1916.pdf
2022-07-22 11:58:27 -03:00
Adhemerval Zanella
f27e5e2178 nptl: Fix ___pthread_unregister_cancel_restore asynchronous restore
This was due a wrong revert done on 404656009b.

Checked on x86_64-linux-gnu and i686-linux-gnu.
2022-07-13 10:44:13 -03:00
Adhemerval Zanella
e070501d12 Replace __libc_multiple_threads with __libc_single_threaded
And also fixes the SINGLE_THREAD_P macro for SINGLE_THREAD_BY_GLOBAL,
since header inclusion single-thread.h is in the wrong order, the define
needs to come before including sysdeps/unix/sysdep.h.  The macro
is now moved to a per-arch single-threade.h header.

The SINGLE_THREAD_P is used on some more places.

Checked on aarch64-linux-gnu and x86_64-linux-gnu.
2022-07-05 10:14:47 -03:00
Adhemerval Zanella
a1bdd81664 Refactor internal-signals.h
The main drive is to optimize the internal usage and required size
when sigset_t is embedded in other data structures.  On Linux, the
current supported signal set requires up to 8 bytes (16 on mips),
was lower than the user defined sigset_t (128 bytes).

A new internal type internal_sigset_t is added, along with the
functions to operate on it similar to the ones for sigset_t.  The
internal-signals.h is also refactored to remove unused functions

Besides small stack usage on some functions (posix_spawn, abort)
it lower the struct pthread by about 120 bytes (112 on mips).

Checked on x86_64-linux-gnu.

Reviewed-by: Arjun Shankar <arjun@redhat.com>
2022-06-30 14:56:21 -03:00
Adhemerval Zanella
d55df811e9 nptl: Remove unused members from struct pthread
It removes both pid_ununsed and cpuclock_offset_ununsed, saving about
12 bytes from struct pthread.

Reviewed-by: Arjun Shankar <arjun@redhat.com>
2022-06-29 16:58:26 -03:00
Adhemerval Zanella
baf2a265c7 misc: Optimize internal usage of __libc_single_threaded
By adding an internal alias to avoid the GOT indirection.
On some architecture, __libc_single_thread may be accessed through
copy relocations and thus it requires to update also the copies
default copy.

This is done by adding a new internal macro,
libc_hidden_data_{proto,def}, which has an addition argument that
specifies the alias name (instead of default __GI_ one).

Checked on x86_64-linux-gnu and i686-linux-gnu.

Reviewed-by: Fangrui Song <maskray@google.com>
2022-06-24 17:45:58 -03:00
Adhemerval Zanella
c7d36dcecc nptl: Fix __libc_cleanup_pop_restore asynchronous restore (BZ#29214)
This was due a wrong revert done on 404656009b.

Checked on x86_64-linux-gnu.
2022-06-08 09:23:02 -03:00
Wangyang Guo
8162147872 nptl: Add backoff mechanism to spinlock loop
When mutiple threads waiting for lock at the same time, once lock owner
releases the lock, waiters will see lock available and all try to lock,
which may cause an expensive CAS storm.

Binary exponential backoff with random jitter is introduced. As try-lock
attempt increases, there is more likely that a larger number threads
compete for adaptive mutex lock, so increase wait time in exponential.
A random jitter is also added to avoid synchronous try-lock from other
threads.

v2: Remove read-check before try-lock for performance.

v3:
1. Restore read-check since it works well in some platform.
2. Make backoff arch dependent, and enable it for x86_64.
3. Limit max backoff to reduce latency in large critical section.

v4: Fix strict-prototypes error in sysdeps/nptl/pthread_mutex_backoff.h

v5: Commit log updated for regression in large critical section.

Result of pthread-mutex-locks bench

Test Platform: Xeon 8280L (2 socket, 112 CPUs in total)
First Row: thread number
First Col: critical section length
Values: backoff vs upstream, time based, low is better

non-critical-length: 1
	1	2	4	8	16	32	64	112	140
0	0.99	0.58	0.52	0.49	0.43	0.44	0.46	0.52	0.54
1	0.98	0.43	0.56	0.50	0.44	0.45	0.50	0.56	0.57
2	0.99	0.41	0.57	0.51	0.45	0.47	0.48	0.60	0.61
4	0.99	0.45	0.59	0.53	0.48	0.49	0.52	0.64	0.65
8	1.00	0.66	0.71	0.63	0.56	0.59	0.66	0.72	0.71
16	0.97	0.78	0.91	0.73	0.67	0.70	0.79	0.80	0.80
32	0.95	1.17	0.98	0.87	0.82	0.86	0.89	0.90	0.90
64	0.96	0.95	1.01	1.01	0.98	1.00	1.03	0.99	0.99
128	0.99	1.01	1.01	1.17	1.08	1.12	1.02	0.97	1.02

non-critical-length: 32
	1	2	4	8	16	32	64	112	140
0	1.03	0.97	0.75	0.65	0.58	0.58	0.56	0.70	0.70
1	0.94	0.95	0.76	0.65	0.58	0.58	0.61	0.71	0.72
2	0.97	0.96	0.77	0.66	0.58	0.59	0.62	0.74	0.74
4	0.99	0.96	0.78	0.66	0.60	0.61	0.66	0.76	0.77
8	0.99	0.99	0.84	0.70	0.64	0.66	0.71	0.80	0.80
16	0.98	0.97	0.95	0.76	0.70	0.73	0.81	0.85	0.84
32	1.04	1.12	1.04	0.89	0.82	0.86	0.93	0.91	0.91
64	0.99	1.15	1.07	1.00	0.99	1.01	1.05	0.99	0.99
128	1.00	1.21	1.20	1.22	1.25	1.31	1.12	1.10	0.99

non-critical-length: 128
	1	2	4	8	16	32	64	112	140
0	1.02	1.00	0.99	0.67	0.61	0.61	0.61	0.74	0.73
1	0.95	0.99	1.00	0.68	0.61	0.60	0.60	0.74	0.74
2	1.00	1.04	1.00	0.68	0.59	0.61	0.65	0.76	0.76
4	1.00	0.96	0.98	0.70	0.63	0.63	0.67	0.78	0.77
8	1.01	1.02	0.89	0.73	0.65	0.67	0.71	0.81	0.80
16	0.99	0.96	0.96	0.79	0.71	0.73	0.80	0.84	0.84
32	0.99	0.95	1.05	0.89	0.84	0.85	0.94	0.92	0.91
64	1.00	0.99	1.16	1.04	1.00	1.02	1.06	0.99	0.99
128	1.00	1.06	0.98	1.14	1.39	1.26	1.08	1.02	0.98

There is regression in large critical section. But adaptive mutex is
aimed for "quick" locks. Small critical section is more common when
users choose to use adaptive pthread_mutex.

Signed-off-by: Wangyang Guo <wangyang.guo@intel.com>
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2022-05-09 14:38:40 -07:00
Adhemerval Zanella
62be968167 nptl: Fix pthread_cancel cancelhandling atomic operations
The 404656009b reversion did not setup the atomic loop to set the
cancel bits correctly.  The fix is essentially what pthread_cancel
did prior 26cfbb7162.

Checked on x86_64-linux-gnu and aarch64-linux-gnu.
2022-04-20 12:01:43 -03:00
Adhemerval Zanella
404656009b nptl: Handle spurious EINTR when thread cancellation is disabled (BZ#29029)
Some Linux interfaces never restart after being interrupted by a signal
handler, regardless of the use of SA_RESTART [1].  It means that for
pthread cancellation, if the target thread disables cancellation with
pthread_setcancelstate and calls such interfaces (like poll or select),
it should not see spurious EINTR failures due the internal SIGCANCEL.

However recent changes made pthread_cancel to always sent the internal
signal, regardless of the target thread cancellation status or type.
To fix it, the previous semantic is restored, where the cancel signal
is only sent if the target thread has cancelation enabled in
asynchronous mode.

The cancel state and cancel type is moved back to cancelhandling
and atomic operation are used to synchronize between threads.  The
patch essentially revert the following commits:

  8c1c0aae20 nptl: Move cancel type out of cancelhandling
  2b51742531 nptl: Move cancel state out of cancelhandling
  26cfbb7162 nptl: Remove CANCELING_BITMASK

However I changed the atomic operation to follow the internal C11
semantic and removed the MACRO usage, it simplifies a bit the
resulting code (and removes another usage of the old atomic macros).

Checked on x86_64-linux-gnu, i686-linux-gnu, aarch64-linux-gnu,
and powerpc64-linux-gnu.

[1] https://man7.org/linux/man-pages/man7/signal.7.html

Reviewed-by: Florian Weimer <fweimer@redhat.com>
Tested-by: Aurelien Jarno <aurelien@aurel32.net>
2022-04-14 12:48:31 -03:00
DJ Delorie
2fe64148a8 Allow for unpriviledged nested containers
If the build itself is run in a container, we may not be able to
fully set up a nested container for test-container testing.
Notably is the mounting of /proc, since it's critical that it
be mounted from within the same PID namespace as its users, and
thus cannot be bind mounted from outside the container like other
mounts.

This patch defaults to using the parent's PID namespace instead of
creating a new one, as this is more likely to be allowed.

If the test needs an isolated PID namespace, it should add the "pidns"
command to its init script.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2022-04-04 14:17:08 -04:00
Adhemerval Zanella
692c2571c8 nptl: Use libc-diag.h with tst-thread-setspecific
And also use libsupport.

Checked on x86_64-linux-gnu and i686-linux-gnu.
2022-03-31 09:02:41 -03:00
John David Anglin
2bbc694df2 nptl: Fix cleanups for stack grows up [BZ# 28899]
_STACK_GROWS_DOWN is defined to 0 when the stack grows up.  The
code in unwind.c used `#ifdef _STACK_GROWS_DOWN' to selct the
stack grows down define for FRAME_LEFT.  As a result, the
_STACK_GROWS_DOWN define was always selected and cleanups were
incorrectly sequenced when the stack grows up.
2022-02-28 15:47:38 +00:00
Adhemerval Zanella
254d3d5aef elf: Fix initial-exec TLS access on audit modules (BZ #28096)
For audit modules and dependencies with initial-exec TLS, we can not
set the initial TLS image on default loader initialization because it
would already be set by the audit setup.  However, subsequent thread
creation would need to follow the default behaviour.

This patch fixes it by setting l_auditing link_map field not only
for the audit modules, but also for all its dependencies.  This is
used on _dl_allocate_tls_init to avoid the static TLS initialization
at load time.

Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Tested-by: Carlos O'Donell <carlos@redhat.com>
2022-02-01 14:49:46 -03:00
Jangwoong Kim
6b8dbbd03a nptl: Effectively skip CAS in spinlock loop
The commit:
"Add LLL_MUTEX_READ_LOCK [BZ #28537]"
SHA1: d672a98a1a

introduced LLL_MUTEX_READ_LOCK, to skip CAS in spinlock loop
if atomic load fails. But, "continue" inside of do-while loop
does not skip the evaluation of escape expression, thus CAS
is not skipped.

Replace do-while with while and skip LLL_MUTEX_TRYLOCK if
LLL_MUTEX_READ_LOCK fails.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
2022-01-20 05:05:09 -08:00
Paul Eggert
581c785bf3 Update copyright dates with scripts/update-copyrights
I used these shell commands:

../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")

and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.

I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah.  I don't
know why I run into these diagnostics whereas others evidently do not.

remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
2022-01-01 11:40:24 -08:00