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* tests: replace system by xsystemFrédéric Bérat2023-06-192-2/+5
| | | | | | 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>
* tests: replace read by xreadFrédéric Bérat2023-06-191-1/+3
| | | | | | | | | | | | | | | 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 d0e3ffb7a58854248f1d5e737610d50cd0a60f46 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>
* Fix all the remaining misspellings -- BZ 25337Paul Pluzhnikov2023-06-0216-25/+25
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* tests: replace write by xwriteFrédéric Bérat2023-06-013-3/+8
| | | | | | | Using write without cheks leads to warn unused result when __wur is enabled. Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
* nptl: Reformat Makefile.Carlos O'Donell2023-05-185-79/+196
| | | | | | | | | 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.
* Created tunable to force small pages on stack allocation.Cupertino Miranda2023-04-204-0/+18
| | | | | | | | | | 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>
* Remove --enable-tunables configure optionAdhemerval Zanella Netto2023-03-292-5/+1
| | | | | | | | | | | | 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>
* Move libc_freeres_ptrs and libc_subfreeres to hidden/weak functionsAdhemerval Zanella Netto2023-03-271-1/+0
| | | | | | | | | | | | | | | | | | | | 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>
* Remove pthread-pi-defines.symAndreas Schwab2023-02-032-11/+1
| | | | | It became unused with the removal of the assembler implementation of the pthread functions.
* Update copyright dates with scripts/update-copyrightsJoseph Myers2023-01-06273-273/+273
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* Define in_int32_t_range to check if the 64 bit time_t syscall should be usedYunQiang Su2022-11-171-2/+2
| | | | | | | | | | | | | | | | | 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>
* elf: Rework exception handling in the dynamic loader [BZ #25486]Florian Weimer2022-11-031-0/+3
| | | | | | | | | | | | | | | | | | | | | | | 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 b65a82e4e757c1e6cb7073916 ("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>
* nptl: Fix pthread_create.c build with clangAdhemerval Zanella2022-11-011-2/+4
| | | | | | | | | | | | | | | | 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>
* linux: Avoid shifting a negative signed on POSIX timer interfaceAdhemerval Zanella2022-10-201-1/+1
| | | | | | | | | | 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>
* nptl: Convert tst-setuid2 to test-driverYu Chien Peter Lin2022-10-031-37/+15
| | | | | | | | 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>
* Use atomic_exchange_release/acquireWilco Dijkstra2022-09-262-2/+2
| | | | | | | 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>
* Use C11 atomics instead of atomic_decrement_and_testWilco Dijkstra2022-09-232-104/+1
| | | | | | | | | | 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>
* Use C11 atomics instead of atomic_increment(_val)Wilco Dijkstra2022-09-233-3/+3
| | | | | | | | | | | 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>
* Use C11 atomics instead of atomic_and/orWilco Dijkstra2022-09-234-4/+4
| | | | | | | | | | 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>
* Use '%z' instead of '%Z' on printf functionsAdhemerval Zanella Netto2022-09-222-14/+14
| | | | | | | | 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>
* Use relaxed atomics since there is no MO dependenceWilco Dijkstra2022-09-132-2/+3
| | | | | | | | 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>
* Use C11 atomics instead of atomic_decrement(_val)Wilco Dijkstra2022-09-092-2/+2
| | | | | | | Replace atomic_decrement and atomic_decrement_val with atomic_fetch_add_relaxed. Reviewed-by: DJ Delorie <dj@redhat.com>
* stdlib: Add arc4random, arc4random_buf, and arc4random_uniform (BZ #4417)Adhemerval Zanella Netto2022-07-221-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* nptl: Fix ___pthread_unregister_cancel_restore asynchronous restoreAdhemerval Zanella2022-07-131-1/+1
| | | | | | This was due a wrong revert done on 404656009b459658. Checked on x86_64-linux-gnu and i686-linux-gnu.
* Replace __libc_multiple_threads with __libc_single_threadedAdhemerval Zanella2022-07-054-36/+1
| | | | | | | | | | | 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.
* Refactor internal-signals.hAdhemerval Zanella2022-06-305-16/+17
| | | | | | | | | | | | | | | | | | 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>
* nptl: Remove unused members from struct pthreadAdhemerval Zanella2022-06-291-7/+0
| | | | | | | It removes both pid_ununsed and cpuclock_offset_ununsed, saving about 12 bytes from struct pthread. Reviewed-by: Arjun Shankar <arjun@redhat.com>
* misc: Optimize internal usage of __libc_single_threadedAdhemerval Zanella2022-06-241-1/+4
| | | | | | | | | | | | | | | 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>
* nptl: Fix __libc_cleanup_pop_restore asynchronous restore (BZ#29214)Adhemerval Zanella2022-06-081-1/+2
| | | | | | This was due a wrong revert done on 404656009b459658. Checked on x86_64-linux-gnu.
* nptl: Add backoff mechanism to spinlock loopWangyang Guo2022-05-091-2/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* nptl: Fix pthread_cancel cancelhandling atomic operationsAdhemerval Zanella2022-04-201-1/+2
| | | | | | | | The 404656009b reversion did not setup the atomic loop to set the cancel bits correctly. The fix is essentially what pthread_cancel did prior 26cfbb7162ad. Checked on x86_64-linux-gnu and aarch64-linux-gnu.
* nptl: Handle spurious EINTR when thread cancellation is disabled (BZ#29029)Adhemerval Zanella2022-04-1410-85/+272
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Allow for unpriviledged nested containersDJ Delorie2022-04-041-0/+4
| | | | | | | | | | | | | | | | | 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>
* nptl: Use libc-diag.h with tst-thread-setspecificAdhemerval Zanella2022-03-311-7/+8
| | | | | | And also use libsupport. Checked on x86_64-linux-gnu and i686-linux-gnu.
* nptl: Fix cleanups for stack grows up [BZ# 28899]John David Anglin2022-02-281-1/+1
| | | | | | | | _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.
* elf: Fix initial-exec TLS access on audit modules (BZ #28096)Adhemerval Zanella2022-02-011-1/+1
| | | | | | | | | | | | | | | | | 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>
* nptl: Effectively skip CAS in spinlock loopJangwoong Kim2022-01-201-3/+2
| | | | | | | | | | | | | | | | The commit: "Add LLL_MUTEX_READ_LOCK [BZ #28537]" SHA1: d672a98a1af106bd68deb15576710cd61363f7a6 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>
* Update copyright dates with scripts/update-copyrightsPaul Eggert2022-01-01274-274/+274
| | | | | | | | | | | | | | | | | | | | | | | 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
* nptl: rseq failure after registration on main thread is fatalFlorian Weimer2021-12-091-1/+2
| | | | | | | | | | | | | | | | | | | | This simplifies the application programming model. Browser sandboxes have already been fixed: Sandbox is incompatible with rseq registration <https://bugzilla.mozilla.org/show_bug.cgi?id=1651701> Allow rseq in the Linux sandboxes. r=gcp <https://hg.mozilla.org/mozilla-central/rev/042425712eb1> Sandbox needs to support rseq system call <https://bugs.chromium.org/p/chromium/issues/detail?id=1104160> Linux sandbox: Allow rseq(2) <https://chromium.googlesource.com/chromium/src.git/+/230675d9ac8f1> Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
* nptl: Add glibc.pthread.rseq tunable to control rseq registrationFlorian Weimer2021-12-091-1/+9
| | | | | | | | This tunable allows applications to register the rseq area instead of glibc. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com> Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
* nptl: Add rseq registrationFlorian Weimer2021-12-092-0/+17
| | | | | | | | | | | | The rseq area is placed directly into struct pthread. rseq registration failure is not treated as an error, so it is possible that threads run with inconsistent registration status. <sys/rseq.h> is not yet installed as a public header. Co-Authored-By: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com> Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
* misc, nptl: Remove stray references to __condvar_load_64_relaxedFlorian Weimer2021-12-061-1/+1
| | | | | | The function was renamed to __atomic_wide_counter_load_relaxed in commit 8bd336a00a5311bf7a9e99b3b0e9f01ff5faa74b ("nptl: Extract <bits/atomic_wide_counter.h> from pthread_cond_common.c").
* nptl: Increase default TCB alignment to 32Florian Weimer2021-12-032-1/+4
| | | | | | | | | | rseq support will use a 32-byte aligned field in struct pthread, so the whole struct needs to have at least that alignment. nptl/tst-tls3mod.c uses TCB_ALIGNMENT, therefore include <descr.h> to obtain the fallback definition. Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* nptl: Do not set signal mask on second setjmp return [BZ #28607]Florian Weimer2021-11-241-2/+2
| | | | | | | | | | | | __libc_signal_restore_set was in the wrong place: It also ran when setjmp returned the second time (after pthread_exit or pthread_cancel). This is observable with blocked pending signals during thread exit. Fixes commit b3cae39dcbfa2432b3f3aa28854d8ac57f0de1b8 ("nptl: Start new threads with all signals blocked [BZ #25098]"). Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* nptl: Extract <bits/atomic_wide_counter.h> from pthread_cond_common.cFlorian Weimer2021-11-173-179/+52
| | | | | | | | | | | | | And make it an installed header. This addresses a few aliasing violations (which do not seem to result in miscompilation due to the use of atomics), and also enables use of wide counters in other parts of the library. The debug output in nptl/tst-cond22 has been adjusted to print the 32-bit values instead because it avoids a big-endian/little-endian difference. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Move assignment out of the CAS conditionH.J. Lu2021-11-152-8/+6
| | | | | | | | | | | | | | | | | | | | | | | | Update commit 49302b8fdf9103b6fc0a398678668a22fa19574c Author: H.J. Lu <hjl.tools@gmail.com> Date: Thu Nov 11 06:54:01 2021 -0800 Avoid extra load with CAS in __pthread_mutex_clocklock_common [BZ #28537] Replace boolean CAS with value CAS to avoid the extra load. and commit 0b82747dc48d5bf0871bdc6da8cb6eec1256355f Author: H.J. Lu <hjl.tools@gmail.com> Date: Thu Nov 11 06:31:51 2021 -0800 Avoid extra load with CAS in __pthread_mutex_lock_full [BZ #28537] Replace boolean CAS with value CAS to avoid the extra load. by moving assignment out of the CAS condition.
* Add LLL_MUTEX_READ_LOCK [BZ #28537]H.J. Lu2021-11-121-0/+7
| | | | | | | | | | | | | | | | CAS instruction is expensive. From the x86 CPU's point of view, getting a cache line for writing is more expensive than reading. See Appendix A.2 Spinlock in: https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/xeon-lock-scaling-analysis-paper.pdf The full compare and swap will grab the cache line exclusive and cause excessive cache line bouncing. Add LLL_MUTEX_READ_LOCK to do an atomic load and skip CAS in spinlock loop if compare may fail to reduce cache line bouncing on contended locks. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
* Avoid extra load with CAS in __pthread_mutex_clocklock_common [BZ #28537]H.J. Lu2021-11-121-5/+5
| | | | | | Replace boolean CAS with value CAS to avoid the extra load. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
* Avoid extra load with CAS in __pthread_mutex_lock_full [BZ #28537]H.J. Lu2021-11-121-5/+5
| | | | | | Replace boolean CAS with value CAS to avoid the extra load. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
* nptl: Fix tst-cancel7 and tst-cancelx7 pidfile raceStafford Horne2021-10-181-6/+3
| | | | | | | | | | | | | | The check for waiting for the pidfile to be created looks wrong. At the point when ACCESS is run the pid file will always be created and accessible as it is created during DO_PREPARE. This means that thread cancellation may be performed before the pid is written to the pidfile. This was found to be flaky when testing on my OpenRISC platform. Fix this by using the semaphore to wait for pidfile pid write completion. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
generated by cgit-pink 1.4.1 (git 2.36.1) at 2024-11-06 03:46:46 +0000