commit 04deeaa9ea
Author: Lucas A. M. Magalhaes <lamm@linux.ibm.com>
Date: Fri Jul 10 19:41:06 2020 -0300
Fix time/tst-cpuclock1 intermitent failures
has 2 issues:
1. It assumes time_t == long which is false on x32.
2. tst-timespec.c is compiled without -fexcess-precision=standard which
generates incorrect results on i686 in support_timespec_check_in_range:
double ratio = (double)observed_norm / expected_norm;
return (lower_bound <= ratio && ratio <= upper_bound);
This patch does
1. Compile tst-timespec.c with -fexcess-precision=standard.
2. Replace long with time_t.
3. Replace LONG_MIN and LONG_MAX with TYPE_MINIMUM (time_t) and
TYPE_MAXIMUM (time_t).
This test fails intermittently in systems with heavy load as
CLOCK_PROCESS_CPUTIME_ID is subject to scheduler pressure. Thus the
test boundaries were relaxed to keep it from failing on such systems.
A refactor of the spent time checking was made with some support
functions. With the advantage to representing time jitter in percent
of the target.
The values used by the test boundaries are all empirical.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
Checked on x86-64-linux-gnu, i686-linux-gnu, powerpc64le-linux-gnu,
and s390x-linux-gnu.
Tested-by: Carlos O'Donell <carlos@redhat.com>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
During testing of localedef running in a minimal container
there were several error cases which were hard to diagnose
since they appeared as strerror (errno) values printed by the
higher level functions. This change adds three new verbose
messages for potential failure paths. The new messages give
the user the opportunity to use -v and display additional
information about why localedef might be failing. I found
these messages useful myself while writing a localedef
container test for --no-hard-links.
Since the changes cleanup the code that handle codeset
normalization we add tst-localedef-path-norm which contains
many sub-tests to verify the correct expected normalization of
codeset strings both when installing to default paths (the
only time normalization is enabled) and installing to absolute
paths. During the refactoring I created at least one
buffer-overflow which valgrind caught, but these tests did not
catch because the exec in the container had a very clean heap
with zero-initialized memory. However, between valgrind and
the tests the results are clean.
The new tst-localedef-path-norm passes without regression on
x86_64.
Change-Id: I28b9f680711ff00252a2cb15625b774cc58ecb9d
It allows parent process to wait for child state using a polling
strategy over procfs on Linux. The polling is used over ptrace to
avoid the need to handle signals on the target pid and to handle some
system specific limitation (such as YAMA).
The polling has some limitations, such as resource consumption due
the procfs read in a loop and the lack of synchronization after the
state is obtained.
The interface idea is to simplify some sleep synchronization waitid
tests and is to reduce timeouts by replacing arbitrary waits.
The testcase forks a child process and runs pldd with PID of
this child. On systems where /proc/sys/kernel/yama/ptrace_scope
differs from zero, pldd will fail with
/usr/bin/pldd: cannot attach to process 3: Operation not permitted
This patch checks if ptrace_scope exists, is zero "classic ptrace permissions"
or one "restricted ptrace". If ptrace_scope exists and has a higher
restriction, then the test is marked as UNSUPPORTED.
The case "restricted ptrace" is handled by rearranging the processes involved
during the test. Now we have the following process tree:
-parent: do_test (performs output checks)
--subprocess 1: pldd_process (becomes pldd via execve)
---subprocess 2: target_process (ptraced via pldd)
ChangeLog:
* elf/tst-pldd.c (do_test): Add UNSUPPORTED check.
Rearrange subprocesses.
(pldd_process): New function.
* support/Makefile (libsupport-routines): Add support_ptrace.
* support/xptrace.h: New file.
* support/support_ptrace.c: Likewise.
nss_db allows for getpwent et al to be called without a set*ent,
but it only works once. After the last get*ent a set*ent is
required to restart, because the end*ent did not properly reset
the module. Resetting it to NULL allows for a proper restart.
If the database doesn't exist, however, end*ent erroniously called
munmap which set errno.
The test case runs "makedb" inside the testroot, so needs selinux
DSOs installed.
It adds useful functions for tests that use struct timespec.
Checked on x86_64-linux-gnu and i686-linux-gnu.
* support/timespec.h: New file. Provide timespec helper functions
along with macros in the style of those in check.h.
* support/timespec.c: New file. Implement check functions declared
in support/timespec.h.
* support/timespec-add.c: New file from gnulib containing
timespec_add implementation that handles overflow.
* support/timespec-sub.c: New file from gnulib containing
timespec_sub implementation that handles overflow.
* support/README: Mention timespec.h.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* support/xclock_gettime.c (xclock_gettime): New file. Provide
clock_gettime wrapper for use in tests that fails the test rather
than returning failure.
* support/xtime.h: New file to declare xclock_gettime.
* support/Makefile: Add xclock_gettime.c.
* support/README: Mention xtime.h.
Its API is similar to support_capture_subprocess, but rather creates a
new process based on the input path and arguments. Under the hoods it
uses posix_spawn to create the new process.
It also allows the use of other support_capture_* functions to check
for expected results and free the resources.
Checked on x86_64-linux-gnu.
* support/Makefile (libsupport-routines): Add support_subprocess,
xposix_spawn, xposix_spawn_file_actions_addclose, and
xposix_spawn_file_actions_adddup2.
(tst-support_capture_subprocess-ARGS): New rule.
* support/capture_subprocess.h (support_capture_subprogram): New
prototype.
* support/support_capture_subprocess.c (support_capture_subprocess):
Refactor to use support_subprocess and support_capture_poll.
(support_capture_subprogram): New function.
* support/tst-support_capture_subprocess.c (write_mode_to_str,
str_to_write_mode, test_common, parse_int, handle_restart,
do_subprocess, do_subprogram, do_multiple_tests): New functions.
(do_test): Add support_capture_subprogram tests.
* support/subprocess.h: New file.
* support/support_subprocess.c: Likewise.
* support/xposix_spawn.c: Likewise.
* support/xposix_spawn_file_actions_addclose.c: Likewise.
* support/xposix_spawn_file_actions_adddup2.c: Likewise.
* support/xspawn.h: Likewise.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
The alignment of TLS variables is wrong if accessed from within a thread
for architectures with tls variant TLS_TCB_AT_TP.
For the main thread the static tls data is properly aligned.
For other threads the alignment depends on the alignment of the thread
pointer as the static tls data is located relative to this pointer.
This patch adds this alignment for TLS_TCB_AT_TP variants in the same way
as it is already done for TLS_DTV_AT_TP. The thread pointer is also already
properly aligned if the user provides its own stack for the new thread.
This patch extends the testcase nptl/tst-tls1.c in order to check the
alignment of the tls variables and it adds a pthread_create invocation
with a user provided stack.
The test itself is migrated from test-skeleton.c to test-driver.c
and the missing support functions xpthread_attr_setstack and xposix_memalign
are added.
ChangeLog:
[BZ #23403]
* nptl/allocatestack.c (allocate_stack): Align pointer pd for
TLS_TCB_AT_TP tls variant.
* nptl/tst-tls1.c: Migrate to support/test-driver.c.
Add alignment checks.
* support/Makefile (libsupport-routines): Add xposix_memalign and
xpthread_setstack.
* support/support.h: Add xposix_memalign.
* support/xthread.h: Add xpthread_attr_setstack.
* support/xposix_memalign.c: New File.
* support/xpthread_attr_setstack.c: Likewise.
For a full analysis of both the pthread_rwlock_tryrdlock() stall
and the pthread_rwlock_trywrlock() stall see:
https://sourceware.org/bugzilla/show_bug.cgi?id=23844#c14
In the pthread_rwlock_trydlock() function we fail to inspect for
PTHREAD_RWLOCK_FUTEX_USED in __wrphase_futex and wake the waiting
readers.
In the pthread_rwlock_trywrlock() function we write 1 to
__wrphase_futex and loose the setting of the PTHREAD_RWLOCK_FUTEX_USED
bit, again failing to wake waiting readers during unlock.
The fix in the case of pthread_rwlock_trydlock() is to check for
PTHREAD_RWLOCK_FUTEX_USED and wake the readers.
The fix in the case of pthread_rwlock_trywrlock() is to only write
1 to __wrphase_futex if we installed the write phase, since all other
readers would be spinning waiting for this step.
We add two new tests, one exercises the stall for
pthread_rwlock_trywrlock() which is easy to exercise, and one exercises
the stall for pthread_rwlock_trydlock() which is harder to exercise.
The pthread_rwlock_trywrlock() test fails consistently without the fix,
and passes after. The pthread_rwlock_tryrdlock() test fails roughly
5-10% of the time without the fix, and passes all the time after.
Signed-off-by: Carlos O'Donell <carlos@redhat.com>
Signed-off-by: Torvald Riegel <triegel@redhat.com>
Signed-off-by: Rik Prohaska <prohaska7@gmail.com>
Co-authored-by: Torvald Riegel <triegel@redhat.com>
Co-authored-by: Rik Prohaska <prohaska7@gmail.com>
There is general agreement that the very short list of things that ISO
C says you can do in an async signal handler should all work when the
handler is running on an alternate signal stack with only MINSIGSTKSZ
space. This patch adds tests to make sure those things do work.
To facilitate this, there is a new set of test support routines for
setting up alternate signal stacks; see support/xsignal.h for the API.
* support/xsignal.h (xalloc_sigstack, xfree_sigstack)
(xget_sigstack_location): New test support functions.
* support/xsigstack.c: New file, implementing them.
* support/tst-xsigstack.c: New test for them.
* support/Makefile: Update.
* signal/tst-minsigstksz-1.c
* signal/tst-minsigstksz-2.c
* signal/tst-minsigstksz-3.c
* signal/tst-minsigstksz-3a.c
* signal/tst-minsigstksz-4.c: New tests.
* signal/Makefile: Run them.
On systems without enough random-access memory, stdlib/test-bz22786
will go deeply into swap and time out, even with a substantial
TIMEOUTFACTOR. This commit adds a facility to construct repeating
strings with alias mappings, so that the requirement for physical
memory, and uses it in stdlib/test-bz22786.
The test-container.c file assumes that ld.so is always named
something like /elf/ld-linux-*.
But e.g. on s390x it is named ld64.so.1 or ld.so.1 on s390.
There are other architectures like power or mips with similar names.
This patch introduces the new global variable support_objdir_elf_ldso
which contains the absolute path to the runtime linker used by the
testsuite, e.g. OBJDIR_PATH/elf/ld-linux-x86-64.so.2.
The check in test-container.c is now comparing against this path.
Without this patch, test-container.c is searching invalid files / directories
and fails to find glibc/nss/tst-nss-test3.root/tst-nss-test3.script.
Then the test tst-nss-test3 fails!
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
ChangeLog:
* support/support.h (support_objdir_elf_ldso): New variable.
* support/support_paths.c (support_objdir_elf_ldso): Likewise.
* support/Makefile (CFLAGS-support_paths.c): Add definition
for OBJDIR_ELF_LDSO_PATH.
* support/test-container.c (main): Search for the ld.so
which is also used by the testsuite.
copy_file_range can't be used to copy a file from glibc source directory
to glibc build directory since they may be on different filesystems.
This patch adds xcopy_file_range for cross-device copy.
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
[BZ #23597]
* support/Makefile (libsupport-routines): Add
support_copy_file_range and xcopy_file_range.
* support/support.h: Include <sys/types.h>.
(support_copy_file_range): New prototype.
* support/support_copy_file_range.c: New file. Copied and
modified from io/copy_file_range-compat.c.
* support/test-container.c (copy_one_file): Call xcopy_file_rang
instead of copy_file_range.
* support/xcopy_file_range.c: New file.
* support/xunistd.h (xcopy_file_range): New prototype.
C99 specifies that the EOF condition on a file is "sticky": once EOF
has been encountered, all subsequent reads should continue to return
EOF until the file is closed or something clears the "end-of-file
indicator" (e.g. fseek, clearerr). This is arguably a change from
C89, where the wording was ambiguous; the BSDs always had sticky EOF,
but the System V lineage would attempt to read from the underlying fd
again. GNU libc has followed System V for as long as we've been
using libio, but nowadays C99 conformance and BSD compatibility are
more important than System V compatibility.
You might wonder if changing the _underflow impls is sufficient to
apply the C99 semantics to all of the many stdio functions that
perform input. It should be enough to cover all paths to _IO_SYSREAD,
and the only other functions that call _IO_SYSREAD are the _seekoff
impls, which is OK because seeking clears EOF, and the _xsgetn impls,
which, as far as I can tell, are unused within glibc.
The test programs in this patch use a pseudoterminal to set up the
necessary conditions. To facilitate this I added a new test-support
function that sets up a pair of pty file descriptors for you; it's
almost the same as BSD openpty, the only differences are that it
allocates the optionally-returned tty pathname with malloc, and that
it crashes if anything goes wrong.
[BZ #1190]
[BZ #19476]
* libio/fileops.c (_IO_new_file_underflow): Return EOF immediately
if the _IO_EOF_SEEN bit is already set; update commentary.
* libio/oldfileops.c (_IO_old_file_underflow): Likewise.
* libio/wfileops.c (_IO_wfile_underflow): Likewise.
* support/support_openpty.c, support/tty.h: New files.
* support/Makefile (libsupport-routines): Add support_openpty.
* libio/tst-fgetc-after-eof.c, wcsmbs/test-fgetwc-after-eof.c:
New test cases.
* libio/Makefile (tests): Add tst-fgetc-after-eof.
* wcsmbs/Makefile (tests): Add tst-fgetwc-after-eof.
This adds system call wrappers for pkey_alloc, pkey_free, pkey_mprotect,
and x86-64 implementations of pkey_get and pkey_set, which abstract over
the PKRU CPU register and hide the actual number of memory protection
keys supported by the CPU. pkey_mprotect with a -1 key is implemented
using mprotect, so it will work even if the kernel does not support the
pkey_mprotect system call.
The system call wrapers use unsigned int instead of unsigned long for
parameters, so that no special treatment for x32 is needed. The flags
argument is currently unused, and the access rights bit mask is limited
to two bits by the current PKRU register layout anyway.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
System defaults vary, and a mere unshare (CLONE_NEWNS) (which is part of
support_become_root) is no longer sufficient.
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Without this fix, the rwlock can fail to execute the explicit hand-over
in certain cases (e.g., empty critical sections that switch quickly between
read and write phases). This can then lead to errors in how __wrphase_futex
is accessed, which in turn can lead to deadlocks.
Current allocate_stack logic for create stacks is to first mmap all
the required memory with the desirable memory and then mprotect the
guard area with PROT_NONE if required. Although it works as expected,
it pessimizes the allocation because it requires the kernel to actually
increase commit charge (it counts against the available physical/swap
memory available for the system).
The only issue is to actually check this change since side-effects are
really Linux specific and to actually account them it would require a
kernel specific tests to parse the system wide information. On the kernel
I checked /proc/self/statm does not show any meaningful difference for
vmm and/or rss before and after thread creation. I could only see
really meaningful information checking on system wide /proc/meminfo
between thread creation: MemFree, MemAvailable, and Committed_AS shows
large difference without the patch. I think trying to use these
kind of information on a testcase is fragile.
The BZ#18988 reports shows that the commit pages are easily seen with
mlockall (MCL_FUTURE) (with lock all pages that become mapped in the
process) however a more straighfoward testcase shows that pthread_create
could be faster using this patch:
--
static const int inner_count = 256;
static const int outer_count = 128;
static
void *thread1(void *arg)
{
return NULL;
}
static
void *sleeper(void *arg)
{
pthread_t ts[inner_count];
for (int i = 0; i < inner_count; i++)
pthread_create (&ts[i], &a, thread1, NULL);
for (int i = 0; i < inner_count; i++)
pthread_join (ts[i], NULL);
return NULL;
}
int main(void)
{
pthread_attr_init(&a);
pthread_attr_setguardsize(&a, 1<<20);
pthread_attr_setstacksize(&a, 1134592);
pthread_t ts[outer_count];
for (int i = 0; i < outer_count; i++)
pthread_create(&ts[i], &a, sleeper, NULL);
for (int i = 0; i < outer_count; i++)
pthread_join(ts[i], NULL);
assert(r == 0);
}
return 0;
}
--
On x86_64 (4.4.0-45-generic, gcc 5.4.0) running the small benchtests
I see:
$ time ./test
real 0m3.647s
user 0m0.080s
sys 0m11.836s
While with the patch I see:
$ time ./test
real 0m0.696s
user 0m0.040s
sys 0m1.152s
So I added a pthread_create benchtest (thread_create) which check
the thread creation latency. As for the simple benchtests, I saw
improvements in thread creation on all architectures I tested the
change.
Checked on x86_64-linux-gnu, i686-linux-gnu, aarch64-linux-gnu,
arm-linux-gnueabihf, powerpc64le-linux-gnu, sparc64-linux-gnu,
and sparcv9-linux-gnu.
[BZ #18988]
* benchtests/thread_create-inputs: New file.
* benchtests/thread_create-source.c: Likewise.
* support/xpthread_attr_setguardsize.c: Likewise.
* support/Makefile (libsupport-routines): Add
xpthread_attr_setguardsize object.
* support/xthread.h: Add xpthread_attr_setguardsize prototype.
* benchtests/Makefile (bench-pthread): Add thread_create.
* nptl/allocatestack.c (allocate_stack): Call mmap with PROT_NONE and
then mprotect the required area.
