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* Remove TLS_TCB_ALIGN and TLS_INIT_TCB_ALIGNFlorian Weimer2021-12-091-6/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TLS_INIT_TCB_ALIGN is not actually used. TLS_TCB_ALIGN was likely introduced to support a configuration where the thread pointer has not the same alignment as THREAD_SELF. Only ia64 seems to use that, but for the stack/pointer guard, not for storing tcbhead_t. Some ports use TLS_TCB_OFFSET and TLS_PRE_TCB_SIZE to shift the thread pointer, potentially landing in a different residue class modulo the alignment, but the changes should not impact that. In general, given that TLS variables have their own alignment requirements, having different alignment for the (unshifted) thread pointer and struct pthread would potentially result in dynamic offsets, leading to more complexity. hppa had different values before: __alignof__ (tcbhead_t), which seems to be 4, and __alignof__ (struct pthread), which was 8 (old default) and is now 32. However, it defines THREAD_SELF as: /* Return the thread descriptor for the current thread. */ # define THREAD_SELF \ ({ struct pthread *__self; \ __self = __get_cr27(); \ __self - 1; \ }) So the thread pointer points after struct pthread (hence __self - 1), and they have to have the same alignment on hppa as well. Similarly, on ia64, the definitions were different. We have: # define TLS_PRE_TCB_SIZE \ (sizeof (struct pthread) \ + (PTHREAD_STRUCT_END_PADDING < 2 * sizeof (uintptr_t) \ ? ((2 * sizeof (uintptr_t) + __alignof__ (struct pthread) - 1) \ & ~(__alignof__ (struct pthread) - 1)) \ : 0)) # define THREAD_SELF \ ((struct pthread *) ((char *) __thread_self - TLS_PRE_TCB_SIZE)) And TLS_PRE_TCB_SIZE is a multiple of the struct pthread alignment (confirmed by the new _Static_assert in sysdeps/ia64/libc-tls.c). On m68k, we have a larger gap between tcbhead_t and struct pthread. But as far as I can tell, the port is fine with that. The definition of TCB_OFFSET is sufficient to handle the shifted TCB scenario. This fixes commit 23c77f60181eb549f11ec2f913b4270af29eee38 ("nptl: Increase default TCB alignment to 32"). Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* nptl: Introduce THREAD_GETMEM_VOLATILEFlorian Weimer2021-12-091-0/+2
| | | | | | This will be needed for rseq TCB access. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
* nptl: Introduce <tcb-access.h> for THREAD_* accessorsFlorian Weimer2021-12-092-113/+131
| | | | | | | These are common between most architectures. Only the x86 targets are outliers. Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
* elf: Remove THREAD_GSCOPE_IN_TCBSergey Bugaev2021-09-161-1/+0
| | | | | | | | | All the ports now have THREAD_GSCOPE_IN_TCB set to 1. Remove all support for !THREAD_GSCOPE_IN_TCB, along with the definition itself. Signed-off-by: Sergey Bugaev <bugaevc@gmail.com> Message-Id: <20210915171110.226187-4-bugaevc@gmail.com> Reviewed-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
* Remove "Contributed by" linesSiddhesh Poyarekar2021-09-032-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | We stopped adding "Contributed by" or similar lines in sources in 2012 in favour of git logs and keeping the Contributors section of the glibc manual up to date. Removing these lines makes the license header a bit more consistent across files and also removes the possibility of error in attribution when license blocks or files are copied across since the contributed-by lines don't actually reflect reality in those cases. Move all "Contributed by" and similar lines (Written by, Test by, etc.) into a new file CONTRIBUTED-BY to retain record of these contributions. These contributors are also mentioned in manual/contrib.texi, so we just maintain this additional record as a courtesy to the earlier developers. The following scripts were used to filter a list of files to edit in place and to clean up the CONTRIBUTED-BY file respectively. These were not added to the glibc sources because they're not expected to be of any use in future given that this is a one time task: https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dc https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02 Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* nptl: Move pthread_spin_trylock into libcFlorian Weimer2021-04-231-3/+10
| | | | The symbol was moved using scripts/move-symbol-to-libc.py.
* nptl: Move pthread_spin_lock into libcFlorian Weimer2021-04-231-2/+8
| | | | The symbol was moved using scripts/move-symbol-to-libc.py.
* nptl: Move pthread_spin_init, Move pthread_spin_unlock into libcFlorian Weimer2021-04-231-5/+11
| | | | | | | For some architectures, the two functions are aliased, so these symbols need to be moved at the same time. The symbols were moved using scripts/move-symbol-to-libc.py.
* x86: Remove low-level lock optimizationFlorian Weimer2021-04-211-1/+0
| | | | | | | | | | | | | | | The current approach is to do this optimizations at a higher level, in generic code, so that single-threaded cases can be specifically targeted. Furthermore, using IS_IN (libc) as a compile-time indicator that all locks are private is no longer correct once process-shared lock implementations are moved into libc. The generic <lowlevellock.h> is not compatible with assembler code (obviously), so it's necessary to remove two long-unused #includes. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* x86_64: Correct THREAD_SETMEM/THREAD_SETMEM_NC for movq [BZ #27591]H.J. Lu2021-04-011-2/+8
| | | | | | | | | | | | | | | | config/i386/constraints.md in GCC has (define_constraint "e" "32-bit signed integer constant, or a symbolic reference known to fit that range (for immediate operands in sign-extending x86-64 instructions)." (match_operand 0 "x86_64_immediate_operand")) Since movq takes a signed 32-bit immediate or a register source operand, use "er", instead of "nr"/"ir", constraint for 32-bit signed integer constant or register on movq. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* x86: Use x86/nptl/pthreaddef.hH.J. Lu2021-02-221-47/+0
| | | | | | | 1. Move sysdeps/i386/nptl/pthreaddef.h to sysdeps/x86/nptl/pthreaddef.h. 2. Remove sysdeps/x86_64/nptl/pthreaddef.h. Reviewed-by: DJ Delorie <dj@redhat.com>
* Update copyright dates with scripts/update-copyrightsPaul Eggert2021-01-026-6/+6
| | | | | | | | | | | | | | | | 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 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
* x86: Fix THREAD_SELF definition to avoid ld.so crash (bug 27004)Jakub Jelinek2020-12-031-1/+6
| | | | | | | | | | | The previous definition of THREAD_SELF did not tell the compiler that %fs (or %gs) usage is invalid for the !DL_LOOKUP_GSCOPE_LOCK case in _dl_lookup_symbol_x. As a result, ld.so could try to use the TCB before it was initialized. As the comment in tls.h explains, asm volatile is undesirable here. Using the __seg_fs (or __seg_gs) namespace does not interfere with optimization, and expresses that THREAD_SELF is potentially trapping.
* nptl: Move stack list variables into _rtld_globalFlorian Weimer2020-11-161-2/+0
| | | | | | | | | Now __thread_gscope_wait (the function behind THREAD_GSCOPE_WAIT, formerly __wait_lookup_done) can be implemented directly in ld.so, eliminating the unprotected GL (dl_wait_lookup_done) function pointer. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* x86: Remove UP macro. Define LOCK_PREFIX unconditionally.Florian Weimer2020-11-132-14/+2
| | | | | | | The UP macro is never defined. Also define LOCK_PREFIX unconditionally, to the same string. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* aarch64: enforce >=64K guard size [BZ #26691]Szabolcs Nagy2020-10-021-0/+3
| | | | | | | | | | | | | | | | | | | | | | | There are several compiler implementations that allow large stack allocations to jump over the guard page at the end of the stack and corrupt memory beyond that. See CVE-2017-1000364. Compilers can emit code to probe the stack such that the guard page cannot be skipped, but on aarch64 the probe interval is 64K by default instead of the minimum supported page size (4K). This patch enforces at least 64K guard on aarch64 unless the guard is disabled by setting its size to 0. For backward compatibility reasons the increased guard is not reported, so it is only observable by exhausting the address space or parsing /proc/self/maps on linux. On other targets the patch has no effect. If the stack probe interval is larger than a page size on a target then ARCH_MIN_GUARD_SIZE can be defined to get large enough stack guard on libc allocated stacks. The patch does not affect threads with user allocated stacks. Fixes bug 26691.
* Linux: Remove remnants of the getcpu cacheFlorian Weimer2020-05-162-2/+1
| | | | | | The getcpu cache was removed from the kernel in Linux 2.6.24. glibc support from the sched_getcpu implementation was removed in commit dd26c44403582fdf10d663170f947dfe4b3207a0 ("Consolidate sched_getcpu").
* nptl: Remove x86_64 cancellation assembly implementations [BZ #25765]Adhemerval Zanella2020-04-031-7/+0
| | | | | | | | | All cancellable syscalls are done by C implementations, so there is no no need to use a specialized implementation to optimize register usage. It fixes BZ #25765. Checked on x86_64-linux-gnu.
* x86: Avoid single-argument _Static_assert in <tls.h>Florian Weimer2020-02-171-8/+12
| | | | | Older GCC versions do not support this extension. Fixes commit f1bdee61797 ("x86 tls: Use _Static_assert for TLS access size assertion").
* x86 tls: Use _Static_assert for TLS access size assertionSamuel Thibault2020-02-171-26/+20
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* linux: Consolidate INLINE_SYSCALLAdhemerval Zanella2020-02-141-1/+1
| | | | | | | | | | | With all Linux ABIs using the expected Linux kABI to indicate syscalls errors, there is no need to replicate the INLINE_SYSCALL. The generic Linux sysdep.h includes errno.h even for !__ASSEMBLER__, which is ok now and it allows cleanup some archaic code that assume otherwise. Checked with a build against all affected ABIs.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2020-01-016-6/+6
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* nptl: Add tests for internal pthread_rwlock_t offsetsAdhemerval Zanella2019-11-261-0/+6
| | | | | | | | | | | | | This patch new build tests to check for internal fields offsets for internal pthread_rwlock_t definition. Althoug the '__data.__flags' field layout should be preserved due static initializators, the patch also adds tests for the futexes that may be used in a shared memory (although using different libc version in such scenario is not really supported). Checked with a build against all affected ABIs. Change-Id: Iccc103d557de13d17e4a3f59a0cad2f4a640c148
* nptl: Cleanup mutex internal offset testsAdhemerval Zanella2019-11-261-4/+0
| | | | | | | | | | | | | The offsets of pthread_mutex_t __data.__nusers, __data.__spins, __data.elision, __data.list are not required to be constant over the releases. Only the __data.__kind is used for static initializers. This patch also adds an additional size check for __data.__kind. Checked with a build against affected ABIs. Change-Id: I7a4e48cc91b4c4ada57e9a5d1b151fb702bfaa9f
* Prefer https to http for gnu.org and fsf.org URLsPaul Eggert2019-09-076-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
* x86_64: Remove wrong THREAD_ATOMIC_* macrosAdhemerval Zanella2019-01-031-37/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The x86 defines optimized THREAD_ATOMIC_* macros where reference always the current thread instead of the one indicated by input 'descr' argument. It work as long the input is the self thread pointer, however it generates wrong code if the semantic is to set a bit atomicialy from another thread. This is not an issue for current GLIBC usage, however the new cancellation code expects that some synchronization code to atomically set bits from different threads. The generic code generates an additional load to reference to TLS segment, for instance the code: THREAD_ATOMIC_BIT_SET (THREAD_SELF, cancelhandling, CANCELED_BIT); Compiles to: lock;orl $4, %fs:776 Where with patch changes it now compiles to: mov %fs:16,%rax lock;orl $4, 776(%rax) If some usage indeed proves to be a hotspot we can add an extra macro with a more descriptive name (THREAD_ATOMIC_BIT_SET_SELF for instance) where x86_64 might optimize it. Checked on x86_64-linux-gnu. * sysdeps/x86_64/nptl/tls.h (THREAD_ATOMIC_CMPXCHG_VAL, THREAD_ATOMIC_AND, THREAD_ATOMIC_BIT_SET): Remove macros.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2019-01-016-6/+6
| | | | | | | * All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
* x86: Rename __glibc_reserved2 to ssp_base in tcbhead_tH.J. Lu2018-07-252-1/+10
| | | | | | | | | | | | | | | This will be used to record the current shadow stack base for shadow stack switching by getcontext, makecontext, setcontext and swapcontext. If the target shadow stack base is the same as the current shadow stack base, we unwind the shadow stack. Otherwise it is a stack switch and we look for a restore token to restore the target shadow stack. * sysdeps/i386/nptl/tcb-offsets.sym (SSP_BASE_OFFSET): New. * sysdeps/i386/nptl/tls.h (tcbhead_t): Replace __glibc_reserved2 with ssp_base. * sysdeps/x86_64/nptl/tcb-offsets.sym (SSP_BASE_OFFSET): New. * sysdeps/x86_64/nptl/tls.h (tcbhead_t): Replace __glibc_reserved2 with ssp_base.
* x86: Rename __glibc_reserved1 to feature_1 in tcbhead_t [BZ #22563]H.J. Lu2018-07-142-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | feature_1 has X86_FEATURE_1_IBT and X86_FEATURE_1_SHSTK bits for CET run-time control. CET_ENABLED, IBT_ENABLED and SHSTK_ENABLED are defined to 1 or 0 to indicate that if CET, IBT and SHSTK are enabled. <tls-setup.h> is added to set up thread-local data. Reviewed-by: Carlos O'Donell <carlos@redhat.com> [BZ #22563] * nptl/pthread_create.c: Include <tls-setup.h>. (__pthread_create_2_1): Call tls_setup_tcbhead. * sysdeps/generic/tls-setup.h: New file. * sysdeps/x86/nptl/tls-setup.h: Likewise. * sysdeps/i386/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): New. * sysdeps/x86_64/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): Likewise. * sysdeps/i386/nptl/tls.h (tcbhead_t): Rename __glibc_reserved1 to feature_1. * sysdeps/x86_64/nptl/tls.h (tcbhead_t): Likewise. * sysdeps/x86/sysdep.h (X86_FEATURE_1_IBT): New. (X86_FEATURE_1_SHSTK): Likewise. (CET_ENABLED): Likewise. (IBT_ENABLED): Likewise. (SHSTK_ENABLED): Likewise.
* i386: Change offset of __private_ss to 0x30 [BZ #23250]H.J. Lu2018-06-121-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sysdeps/i386/nptl/tls.h has typedef struct { void *tcb; /* Pointer to the TCB. Not necessarily the thread descriptor used by libpthread. */ dtv_t *dtv; void *self; /* Pointer to the thread descriptor. */ int multiple_threads; uintptr_t sysinfo; uintptr_t stack_guard; uintptr_t pointer_guard; int gscope_flag; int __glibc_reserved1; /* Reservation of some values for the TM ABI. */ void *__private_tm[4]; /* GCC split stack support. */ void *__private_ss; } tcbhead_t; The offset of __private_ss is 0x34. But GCC defines /* We steal the last transactional memory word. */ #define TARGET_THREAD_SPLIT_STACK_OFFSET 0x30 and libgcc/config/i386/morestack.S has cmpl %gs:0x30,%eax # See if we have enough space. movl %eax,%gs:0x30 # Save the new stack boundary. movl %eax,%gs:0x30 # Save the new stack boundary. movl %ecx,%gs:0x30 # Save new stack boundary. movl %eax,%gs:0x30 movl %gs:0x30,%eax movl %eax,%gs:0x30 Since update TARGET_THREAD_SPLIT_STACK_OFFSET changes split stack ABI, this patch updates tcbhead_t to match GCC. [BZ #23250] [BZ #10686] * sysdeps/i386/nptl/tls.h (tcbhead_t): Change __private_tm[4] to _private_tm[3] and add __glibc_reserved2. Add _Static_assert of offset of __private_ss == 0x30. * sysdeps/x86_64/nptl/tls.h: Add _Static_assert of offset of __private_ss == 0x40 for ILP32 and == 0x70 for LP64.
* nptl: Remove __ASSUME_PRIVATE_FUTEXH.J. Lu2018-05-172-7/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since __ASSUME_PRIVATE_FUTEX is always defined, this patch removes the !__ASSUME_PRIVATE_FUTEX paths. Tested with build-many-glibcs.py. * nptl/allocatestack.c (allocate_stack): Remove the !__ASSUME_PRIVATE_FUTEX paths. * nptl/descr.h (header): Remove the !__ASSUME_PRIVATE_FUTEX path. * nptl/nptl-init.c (__pthread_initialize_minimal_internal): Likewise. * sysdeps/i386/nptl/tcb-offsets.sym (PRIVATE_FUTEX): Removed. * sysdeps/powerpc/nptl/tcb-offsets.sym (PRIVATE_FUTEX): Likewise. * sysdeps/sh/nptl/tcb-offsets.sym (PRIVATE_FUTEX): Likewise. * sysdeps/x86_64/nptl/tcb-offsets.sym (PRIVATE_FUTEX): Likewise. * sysdeps/i386/nptl/tls.h: (tcbhead_t): Remve the !__ASSUME_PRIVATE_FUTEX path. * sysdeps/s390/nptl/tls.h (tcbhead_t): Likewise. * sysdeps/sparc/nptl/tls.h (tcbhead_t): Likewise. * sysdeps/x86_64/nptl/tls.h (tcbhead_t): Likewise. * sysdeps/unix/sysv/linux/i386/lowlevellock.S: Remove the !__ASSUME_PRIVATE_FUTEX macros. * sysdeps/unix/sysv/linux/lowlevellock-futex.h: Likewise. * sysdeps/unix/sysv/linux/x86_64/cancellation.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/lowlevellock.S: Likewise. * sysdeps/unix/sysv/linux/kernel-features.h (__ASSUME_PRIVATE_FUTEX): Removed.
* hurd: add gscope supportSamuel Thibault2018-03-111-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | * elf/dl-support.c [!THREAD_GSCOPE_IN_TCB] (_dl_thread_gscope_count): Define variable. * sysdeps/generic/ldsodefs.h [!THREAD_GSCOPE_IN_TCB] (struct rtld_global): Add _dl_thread_gscope_count member. * sysdeps/mach/hurd/tls.h: Include <atomic.h>. [!defined __ASSEMBLER__] (THREAD_GSCOPE_GLOBAL, THREAD_GSCOPE_SET_FLAG, THREAD_GSCOPE_RESET_FLAG, THREAD_GSCOPE_WAIT): Define macros. * sysdeps/generic/tls.h: Document THREAD_GSCOPE_IN_TCB. * sysdeps/aarch64/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/alpha/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/arm/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/hppa/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/i386/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/ia64/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/m68k/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/microblaze/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/mips/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/nios2/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/powerpc/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/riscv/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/s390/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/sh/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/sparc/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/tile/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1. * sysdeps/x86_64/nptl/tls.h: Define THREAD_GSCOPE_IN_TCB to 1.
* Revert Intel CET changes to __jmp_buf_tag (Bug 22743)Carlos O'Donell2018-01-252-5/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit cba595c350e52194e10c0006732e1991e3d0803b and commit f81ddabffd76ac9dd600b02adbf3e1dac4bb10ec, ABI compatibility with applications was broken by increasing the size of the on-stack allocated __pthread_unwind_buf_t beyond the oringal size. Applications only have the origianl space available for __pthread_unwind_register, and __pthread_unwind_next to use, any increase in the size of __pthread_unwind_buf_t causes these functions to write beyond the original structure into other on-stack variables leading to segmentation faults in common applications like vlc. The only workaround is to version those functions which operate on the old sized objects, but this must happen in glibc 2.28. Thank you to Andrew Senkevich, H.J. Lu, and Aurelien Jarno, for submitting reports and tracking the issue down. The commit reverts the above mentioned commits and testing on x86_64 shows that the ABI compatibility is restored. A tst-cleanup1 regression test linked with an older glibc now passes when run with the newly built glibc. Previously a tst-cleanup1 linked with an older glibc would segfault when run with an affected glibc build. Tested on x86_64 with no regressions. Signed-off-by: Carlos O'Donell <carlos@redhat.com>
* Update copyright dates with scripts/update-copyrights.Joseph Myers2018-01-016-6/+6
| | | | | | | * All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
* x86: Add feature_1 to tcbhead_t [BZ #22563]H.J. Lu2017-12-192-1/+5
| | | | | | | | | | | | | | | | | | On x86, padding in struct __jmp_buf_tag is used for shadow stack pointer to support Shadow Stack in Intel Control-flow Enforcemen Technology. cancel_jmp_buf has been updated to include saved_mask so that it is as large as struct __jmp_buf_tag. We must suport the old cancel_jmp_buf in existing binaries. Since symbol versioning doesn't work on cancel_jmp_buf, feature_1 is added to tcbhead_t so that setjmp and longjmp can check if shadow stack is enabled. NB: Shadow stack is enabled only if all modules are shadow stack enabled. [BZ #22563] * sysdeps/i386/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): New. * sysdeps/i386/nptl/tls.h (tcbhead_t): Add feature_1. * sysdeps/x86_64/nptl/tcb-offsets.sym (FEATURE_1_OFFSET): New. * sysdeps/x86_64/nptl/tls.h (tcbhead_t): Rename __glibc_unused1 to feature_1.
* nptl: Add tests for internal pthread_mutex_t offsetsAdhemerval Zanella2017-11-071-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds a new build test to check for internal fields offsets for user visible internal field. Although currently the only field which is statically initialized to a non zero value is pthread_mutex_t.__data.__kind value, the tests also check the offset of __kind, __spins, __elision (if supported), and __list internal member. A internal header (pthread-offset.h) is added to each major ABI with the reference value. Checked on x86_64-linux-gnu and with a build check for all affected ABIs (aarch64-linux-gnu, alpha-linux-gnu, arm-linux-gnueabihf, hppa-linux-gnu, i686-linux-gnu, ia64-linux-gnu, m68k-linux-gnu, microblaze-linux-gnu, mips64-linux-gnu, mips64-n32-linux-gnu, mips-linux-gnu, powerpc64le-linux-gnu, powerpc-linux-gnu, s390-linux-gnu, s390x-linux-gnu, sh4-linux-gnu, sparc64-linux-gnu, sparcv9-linux-gnu, tilegx-linux-gnu, tilegx-linux-gnu-x32, tilepro-linux-gnu, x86_64-linux-gnu, and x86_64-linux-x32). * nptl/pthreadP.h (ASSERT_PTHREAD_STRING, ASSERT_PTHREAD_INTERNAL_OFFSET): New macro. * nptl/pthread_mutex_init.c (__pthread_mutex_init): Add build time checks for internal pthread_mutex_t offsets. * sysdeps/aarch64/nptl/pthread-offsets.h (__PTHREAD_MUTEX_NUSERS_OFFSET, __PTHREAD_MUTEX_KIND_OFFSET, __PTHREAD_MUTEX_SPINS_OFFSET, __PTHREAD_MUTEX_ELISION_OFFSET, __PTHREAD_MUTEX_LIST_OFFSET): New macro. * sysdeps/alpha/nptl/pthread-offsets.h: Likewise. * sysdeps/arm/nptl/pthread-offsets.h: Likewise. * sysdeps/hppa/nptl/pthread-offsets.h: Likewise. * sysdeps/i386/nptl/pthread-offsets.h: Likewise. * sysdeps/ia64/nptl/pthread-offsets.h: Likewise. * sysdeps/m68k/nptl/pthread-offsets.h: Likewise. * sysdeps/microblaze/nptl/pthread-offsets.h: Likewise. * sysdeps/mips/nptl/pthread-offsets.h: Likewise. * sysdeps/nios2/nptl/pthread-offsets.h: Likewise. * sysdeps/powerpc/nptl/pthread-offsets.h: Likewise. * sysdeps/s390/nptl/pthread-offsets.h: Likewise. * sysdeps/sh/nptl/pthread-offsets.h: Likewise. * sysdeps/sparc/nptl/pthread-offsets.h: Likewise. * sysdeps/tile/nptl/pthread-offsets.h: Likewise. * sysdeps/x86_64/nptl/pthread-offsets.h: Likewise. Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Remove CALL_THREAD_FCT macroAdhemerval Zanella2017-04-041-12/+0
| | | | | | | | | | | | | | | | This patch removes CALL_THREAD_FCT macro usage and its defition for x86. For 32 bits it usage is only for force 16 stack alignment, however stack is already explicit aligned in clone syscall. For 64 bits and x32 it just a function call and there is no need to code it with inline assembly. Checked on i686-linux-gnu, x86_64-linux-gnu, and x86_64-linux-gnu-x32. * nptl/pthread_create.c (START_THREAD_DEFN): Remove CALL_THREAD_FCT macro usage. * sysdeps/i386/nptl/tls.h (CALL_THREAD_FCT): Remove definition. * sysdeps/x86_64/nptl/tls.h (CALL_THREAD_FCT): Likewise. * sysdeps/x86_64/32/nptl/tls.h: Remove file.
* Narrowing the visibility of libc-internal.h even further.Zack Weinberg2017-03-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | posix/wordexp-test.c used libc-internal.h for PTR_ALIGN_DOWN; similar to what was done with libc-diag.h, I have split the definitions of cast_to_integer, ALIGN_UP, ALIGN_DOWN, PTR_ALIGN_UP, and PTR_ALIGN_DOWN to a new header, libc-pointer-arith.h. It then occurred to me that the remaining declarations in libc-internal.h are mostly to do with early initialization, and probably most of the files including it, even in the core code, don't need it anymore. Indeed, only 19 files actually need what remains of libc-internal.h. 23 others need libc-diag.h instead, and 12 need libc-pointer-arith.h instead. No file needs more than one of them, and 16 don't need any of them! So, with this patch, libc-internal.h stops including libc-diag.h as well as losing the pointer arithmetic macros, and all including files are adjusted. * include/libc-pointer-arith.h: New file. Define cast_to_integer, ALIGN_UP, ALIGN_DOWN, PTR_ALIGN_UP, and PTR_ALIGN_DOWN here. * include/libc-internal.h: Definitions of above macros moved from here. Don't include libc-diag.h anymore either. * posix/wordexp-test.c: Include stdint.h and libc-pointer-arith.h. Don't include libc-internal.h. * debug/pcprofile.c, elf/dl-tunables.c, elf/soinit.c, io/openat.c * io/openat64.c, misc/ptrace.c, nptl/pthread_clock_gettime.c * nptl/pthread_clock_settime.c, nptl/pthread_cond_common.c * string/strcoll_l.c, sysdeps/nacl/brk.c * sysdeps/unix/clock_settime.c * sysdeps/unix/sysv/linux/i386/get_clockfreq.c * sysdeps/unix/sysv/linux/ia64/get_clockfreq.c * sysdeps/unix/sysv/linux/powerpc/get_clockfreq.c * sysdeps/unix/sysv/linux/sparc/sparc64/get_clockfreq.c: Don't include libc-internal.h. * elf/get-dynamic-info.h, iconv/loop.c * iconvdata/iso-2022-cn-ext.c, locale/weight.h, locale/weightwc.h * misc/reboot.c, nis/nis_table.c, nptl_db/thread_dbP.h * nscd/connections.c, resolv/res_send.c, soft-fp/fmadf4.c * soft-fp/fmasf4.c, soft-fp/fmatf4.c, stdio-common/vfscanf.c * sysdeps/ieee754/dbl-64/e_lgamma_r.c * sysdeps/ieee754/dbl-64/k_rem_pio2.c * sysdeps/ieee754/flt-32/e_lgammaf_r.c * sysdeps/ieee754/flt-32/k_rem_pio2f.c * sysdeps/ieee754/ldbl-128/k_tanl.c * sysdeps/ieee754/ldbl-128ibm/k_tanl.c * sysdeps/ieee754/ldbl-96/e_lgammal_r.c * sysdeps/ieee754/ldbl-96/k_tanl.c, sysdeps/nptl/futex-internal.h: Include libc-diag.h instead of libc-internal.h. * elf/dl-load.c, elf/dl-reloc.c, locale/programs/locarchive.c * nptl/nptl-init.c, string/strcspn.c, string/strspn.c * malloc/malloc.c, sysdeps/i386/nptl/tls.h * sysdeps/nacl/dl-map-segments.h, sysdeps/x86_64/atomic-machine.h * sysdeps/unix/sysv/linux/spawni.c * sysdeps/x86_64/nptl/tls.h: Include libc-pointer-arith.h instead of libc-internal.h. * elf/get-dynamic-info.h, sysdeps/nacl/dl-map-segments.h * sysdeps/x86_64/atomic-machine.h: Add multiple include guard.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2017-01-016-6/+6
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* Remove cached PID/TID in cloneAdhemerval Zanella2016-11-241-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch remove the PID cache and usage in current GLIBC code. Current usage is mainly used a performance optimization to avoid the syscall, however it adds some issues: - The exposed clone syscall will try to set pid/tid to make the new thread somewhat compatible with current GLIBC assumptions. This cause a set of issue with new workloads and usecases (such as BZ#17214 and [1]) as well for new internal usage of clone to optimize other algorithms (such as clone plus CLONE_VM for posix_spawn, BZ#19957). - The caching complexity also added some bugs in the past [2] [3] and requires more effort of each port to handle such requirements (for both clone and vfork implementation). - Caching performance gain in mainly on getpid and some specific code paths. The getpid performance leverage is questionable [4], either by the idea of getpid being a hotspot as for the getpid implementation itself (if it is indeed a justifiable hotspot a vDSO symbol could let to a much more simpler solution). Other usage is mainly for non usual code paths, such as pthread cancellation signal and handling. For thread creation (on stack allocation) the code simplification in fact adds some performance gain due the no need of transverse the stack cache and invalidate each element pid. Other thread usages will require a direct getpid syscall, such as cancellation/setxid signal, thread cancellation, thread fail path (at create_thread), and thread signal (pthread_kill and pthread_sigqueue). However these are hardly usual hotspots and I think adding a syscall is justifiable. It also simplifies both the clone and vfork arch-specific implementation. And by review each fork implementation there are some discrepancies that this patch also solves: - microblaze clone/vfork does not set/reset the pid/tid field - hppa uses the default vfork implementation that fallback to fork. Since vfork is deprecated I do not think we should bother with it. The patch also removes the TID caching in clone. My understanding for such semantic is try provide some pthread usage after a user program issue clone directly (as done by thread creation with CLONE_PARENT_SETTID and pthread tid member). However, as stated before in multiple discussions threads, GLIBC provides clone syscalls without further supporting all this semantics. I ran a full make check on x86_64, x32, i686, armhf, aarch64, and powerpc64le. For sparc32, sparc64, and mips I ran the basic fork and vfork tests from posix/ folder (on a qemu system). So it would require further testing on alpha, hppa, ia64, m68k, nios2, s390, sh, and tile (I excluded microblaze because it is already implementing the patch semantic regarding clone/vfork). [1] https://codereview.chromium.org/800183004/ [2] https://sourceware.org/ml/libc-alpha/2006-07/msg00123.html [3] https://sourceware.org/bugzilla/show_bug.cgi?id=15368 [4] http://yarchive.net/comp/linux/getpid_caching.html * sysdeps/nptl/fork.c (__libc_fork): Remove pid cache setting. * nptl/allocatestack.c (allocate_stack): Likewise. (__reclaim_stacks): Likewise. (setxid_signal_thread): Obtain pid through syscall. * nptl/nptl-init.c (sigcancel_handler): Likewise. (sighandle_setxid): Likewise. * nptl/pthread_cancel.c (pthread_cancel): Likewise. * sysdeps/unix/sysv/linux/pthread_kill.c (__pthread_kill): Likewise. * sysdeps/unix/sysv/linux/pthread_sigqueue.c (pthread_sigqueue): Likewise. * sysdeps/unix/sysv/linux/createthread.c (create_thread): Likewise. * sysdeps/unix/sysv/linux/getpid.c: Remove file. * nptl/descr.h (struct pthread): Change comment about pid value. * nptl/pthread_getattr_np.c (pthread_getattr_np): Remove thread pid assert. * sysdeps/unix/sysv/linux/pthread-pids.h (__pthread_initialize_pids): Do not set pid value. * nptl_db/td_ta_thr_iter.c (iterate_thread_list): Remove thread pid cache check. * nptl_db/td_thr_validate.c (td_thr_validate): Likewise. * sysdeps/aarch64/nptl/tcb-offsets.sym: Remove pid offset. * sysdeps/alpha/nptl/tcb-offsets.sym: Likewise. * sysdeps/arm/nptl/tcb-offsets.sym: Likewise. * sysdeps/hppa/nptl/tcb-offsets.sym: Likewise. * sysdeps/i386/nptl/tcb-offsets.sym: Likewise. * sysdeps/ia64/nptl/tcb-offsets.sym: Likewise. * sysdeps/m68k/nptl/tcb-offsets.sym: Likewise. * sysdeps/microblaze/nptl/tcb-offsets.sym: Likewise. * sysdeps/mips/nptl/tcb-offsets.sym: Likewise. * sysdeps/nios2/nptl/tcb-offsets.sym: Likewise. * sysdeps/powerpc/nptl/tcb-offsets.sym: Likewise. * sysdeps/s390/nptl/tcb-offsets.sym: Likewise. * sysdeps/sh/nptl/tcb-offsets.sym: Likewise. * sysdeps/sparc/nptl/tcb-offsets.sym: Likewise. * sysdeps/tile/nptl/tcb-offsets.sym: Likewise. * sysdeps/x86_64/nptl/tcb-offsets.sym: Likewise. * sysdeps/unix/sysv/linux/aarch64/clone.S: Remove pid and tid caching. * sysdeps/unix/sysv/linux/alpha/clone.S: Likewise. * sysdeps/unix/sysv/linux/arm/clone.S: Likewise. * sysdeps/unix/sysv/linux/hppa/clone.S: Likewise. * sysdeps/unix/sysv/linux/i386/clone.S: Likewise. * sysdeps/unix/sysv/linux/ia64/clone2.S: Likewise. * sysdeps/unix/sysv/linux/mips/clone.S: Likewise. * sysdeps/unix/sysv/linux/nios2/clone.S: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/clone.S: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/clone.S: Likewise. * sysdeps/unix/sysv/linux/s390/s390-32/clone.S: Likewise. * sysdeps/unix/sysv/linux/s390/s390-64/clone.S: Likewise. * sysdeps/unix/sysv/linux/sh/clone.S: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc32/clone.S: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/clone.S: Likewise. * sysdeps/unix/sysv/linux/tile/clone.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/clone.S: Likewise. * sysdeps/unix/sysv/linux/aarch64/vfork.S: Remove pid set and reset. * sysdeps/unix/sysv/linux/alpha/vfork.S: Likewise. * sysdeps/unix/sysv/linux/arm/vfork.S: Likewise. * sysdeps/unix/sysv/linux/i386/vfork.S: Likewise. * sysdeps/unix/sysv/linux/ia64/vfork.S: Likewise. * sysdeps/unix/sysv/linux/m68k/clone.S: Likewise. * sysdeps/unix/sysv/linux/m68k/vfork.S: Likewise. * sysdeps/unix/sysv/linux/mips/vfork.S: Likewise. * sysdeps/unix/sysv/linux/nios2/vfork.S: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/vfork.S: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/vfork.S: Likewise. * sysdeps/unix/sysv/linux/s390/s390-32/vfork.S: Likewise. * sysdeps/unix/sysv/linux/s390/s390-64/vfork.S: Likewise. * sysdeps/unix/sysv/linux/sh/vfork.S: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc32/vfork.S: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/vfork.S: Likewise. * sysdeps/unix/sysv/linux/tile/vfork.S: Likewise. * sysdeps/unix/sysv/linux/x86_64/vfork.S: Likewise. * sysdeps/unix/sysv/linux/tst-clone2.c (f): Remove direct pthread struct access. (clone_test): Remove function. (do_test): Rewrite to take in consideration pid is not cached anymore.
* elf: Consolidate machine-agnostic DTV definitions in <dl-dtv.h>Florian Weimer2016-06-201-12/+1
| | | | | Identical definitions of dtv_t and TLS_DTV_UNALLOCATED were repeated for all architectures using DTVs.
* 2016-01-20 Paul Pluzhnikov <ppluzhnikov@google.com>Paul Pluzhnikov2016-01-203-15/+10
| | | | | | | | | [BZ #19490] * sysdeps/unix/sysv/linux/x86_64/pthread_cond_broadcast.S (pthread_cond_broadcast): Use ENTRY/END * sysdeps/unix/sysv/linux/x86_64/pthread_cond_signal.S (pthread_cond_signal): Likewise * sysdeps/x86_64/nptl/pthread_spin_lock.S (pthread_spin_lock): Likewise * sysdeps/x86_64/nptl/pthread_spin_trylock.S (pthread_spin_trylock): Likewise * sysdeps/x86_64/nptl/pthread_spin_unlock.S (pthread_spin_unlock): Likewise
* Update copyright dates with scripts/update-copyrights.Joseph Myers2016-01-046-6/+6
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* Save and restore vector registers in x86-64 ld.soH.J. Lu2015-08-252-39/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds SSE, AVX and AVX512 versions of _dl_runtime_resolve and _dl_runtime_profile, which save and restore the first 8 vector registers used for parameter passing. elf_machine_runtime_setup selects the proper _dl_runtime_resolve or _dl_runtime_profile based on _dl_x86_cpu_features. It avoids race condition caused by FOREIGN_CALL macros, which are only used for x86-64. Performance impact of saving and restoring 8 vector registers are negligible on Nehalem, Sandy Bridge, Ivy Bridge and Haswell when ld.so is optimized with SSE2. [BZ #15128] * sysdeps/x86_64/Makefile [$(subdir) == elf] (tests): Add ifuncmain8. (modules-names): Add ifuncmod8. ($(objpfx)ifuncmain8): New rule. * sysdeps/x86_64/dl-machine.h: Include <dl-procinfo.h> and <cpuid.h>. (elf_machine_runtime_setup): Use _dl_runtime_resolve_sse, _dl_runtime_resolve_avx, or _dl_runtime_resolve_avx512, _dl_runtime_profile_sse, _dl_runtime_profile_avx, or _dl_runtime_profile_avx512, based on HAS_ARCH_FEATURE. * sysdeps/x86_64/dl-trampoline.S: Rewrite. * sysdeps/x86_64/dl-trampoline.h: Likewise. * sysdeps/x86_64/ifuncmain8.c: New file. * sysdeps/x86_64/ifuncmod8.c: Likewise. * sysdeps/x86_64/nptl/tcb-offsets.sym (RTLD_SAVESPACE_SSE): Removed. * sysdeps/x86_64/nptl/tls.h (__128bits): Removed. (tcbhead_t): Change rtld_must_xmm_save to __glibc_unused1. Change rtld_savespace_sse to __glibc_unused2. (RTLD_CHECK_FOREIGN_CALL): Removed. (RTLD_ENABLE_FOREIGN_CALL): Likewise. (RTLD_PREPARE_FOREIGN_CALL): Likewise. (RTLD_FINALIZE_FOREIGN_CALL): Likewise.
* NPTL: swap comments for THREAD_SETMEM and THREAD_SETMEM_NC for i386 and x86_64Martin Galvan2015-03-281-2/+2
| | | | | The comments for THREAD_SETMEM and THREAD_SETMEM_NC were swapped for i386 and x86_64; this patch fixes that.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2015-01-026-6/+6
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* Remove configure tests for assembler CFI support.Joseph Myers2014-06-262-57/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch removes configure tests for assembler CFI support (and thereby eliminates an architecture-specific case in the main configure.ac), instead assuming that support is present unconditionally. The main test was added in 2003 around the time CFI support was added to the assembler. cfi_personality and cfi_lsda support were added to the assembler in 2006. cfi_sections support was added in 2009, a few weeks before binutils 2.20 was released; it's in 2.20, the minimum supported version, so even that configure test is obsolete. Tested x86_64 that the installed shared libraries are unchanged by this patch. * configure.ac (libc_cv_asm_cfi_directives): Remove configure test. * configure: Regenerated. * config.h.in (HAVE_ASM_CFI_DIRECTIVES): Remove macro undefine. * sysdeps/arm/configure.ac (libc_cv_asm_cfi_directive_sections): Remove configure test. * sysdeps/arm/configure: Regenerated. * sysdeps/nptl/configure.ac: Do not check libc_cv_asm_cfi_directives. * sysdeps/nptl/configure: Regenerated. * sysdeps/x86_64/nptl/configure.ac: Remove file. * sysdeps/x86_64/nptl/configure: Remove generated file. * b/sysdeps/generic/sysdep.h [HAVE_ASM_CFI_DIRECTIVES]: Make code unconditional. [!HAVE_ASM_CFI_DIRECTIVES]: Remove conditional code.
* x86: Consolidate unnecessary nptl/ subdirectories.Roland McGrath2014-06-241-1/+0
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* Clean up stack-coloring macros.Roland McGrath2014-06-201-7/+0
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* Include <kernel-features.h> explicitly where required.Joseph Myers2014-06-201-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | This patch makes files using __ASSUME_* macros include <kernel-features.h> explicitly, rather than relying on some other header (such as tls.h, lowlevellock.h or pthreadP.h) to include it implicitly. (I omitted cases where I've already posted or am testing the patch that stops the file from needing __ASSUME_* at all.) This accords with the general principle of making source files include the headers for anything they use, and also helps make it safe to remove <kernel-features.h> includes from any file that doesn't use __ASSUME_* (some of those may be stray includes left behind after increasing the minimum kernel version, others may never have been needed or may have become obsolete after some other change). Tested x86_64 that the disassembly of installed shared libraries is unchanged by this patch. * nptl/pthread_cond_wait.c: Include <kernel-features.h>. * nptl/pthread_rwlock_timedrdlock.c: Likewise. * nptl/pthread_rwlock_timedwrlock.c: Likewise. * nptl/sysdeps/unix/sysv/linux/lowlevelrobustlock.c: Likewise. * nscd/nscd.c: Likewise. * sysdeps/i386/nptl/tcb-offsets.sym: Likewise. * sysdeps/powerpc/nptl/tcb-offsets.sym: Likewise. * sysdeps/sh/nptl/tcb-offsets.sym: Likewise. * sysdeps/x86_64/nptl/tcb-offsets.sym: Likewise.