| Commit message (Collapse) | Author | Age | Files | Lines |
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The fallback allocation is removed, so the possible size constraint
should be analyzed just once; __alloc_dir assumes that 'statp'
argument is non-null, and the max_buffer_size move to close its
used.
Checked on x86_64-linux-gnu and i686-linux-gnu.
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This generic implementation already expects a getdents API which
is Linux specific. It also allows simplify it by assuming
_DIRENT_HAVE_D_RECLEN and _DIRENT_HAVE_D_OFF support.
The readdir are also expanded on each required implementation,
futher fixes and improvements will make parametrize the
implementation more complex.
Checked on x86_64-linux-gnu, i686-linux-gnu, and with a build
for all affected ABIs.
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It basically calls the 64-bit time_t wait4 internal symbol.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
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It was made deprecated on 2.31, so it moves to compat symbol after
two releases. It was also removed from exported symbol for riscv32
(since ABI will be supported on for 2.33).
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
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The generic implementation does not support time64 and the default
one return overflow for invalid tv_sec with UTIME_NOW / UTIME_OMIT
(which is valid since tv_sec in such cases is ignored by the
kernel).
Checked on x86_64-linux-gnu and i686-linux-gnu (on 5.4 and on 4.15
kernel).
Reviewed-by: Lukasz Majewski <lukma@denx.de>
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Although not required by the standards, some code expects that a
successful stat call should not set errno. However since aa03f722f3b99
'linux: Add {f}stat{at} y2038 support', on 32-bit systems with 32-bit
time_t supporrt, stat implementation will first issues __NR_statx and
if it fails with ENOSYS issue the system stat syscall.
On architecture running on kernel without __NR_statx support the
first call will set the errno to ENOSYS, even when the following stat
syscall might not fail.
This patch fixes by using INTERNAL_SYSCALL and only setting the errno
value when function returns.
Checked on i686-linux-gnu, x86_64-linux-gnu, sparc64-linux-gnu,
sparcv9-linux-gnu, powerpc64-linux-gnu, powerpc64le-linux-gnu,
arm-linux-gnueabihf, and aarch64-linux-gnu.
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The Linux shminfo fields are '__syscall_ulong_t' (which is 64-bit
for x32). This patch fixes the test to compare againt the correct
type and to only clamp the value if '__syscall_ulong_t' is the same
size of 'unsigned long int'.
Checked on x86_64-linux-gnu-x32.
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Child of vfork should either call _exit or one of the exec family of
functions. But normally there is nothing to prevent child of vfork from
return of the vfork-calling function. Simpilfy x86 vfork when shadow
stack is in use to introduce mismatched shadow stack in child of vfork
to trigger SIGSEGV when the child returns from the function in which
vfork was called.
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f_flags is added into struct statfs since Linux 2.6.36, which is lacked
in glibc's statfs64.c until now. So mount flags is uninitialized on
platforms having no statfs64 syscall in kernel, e.g., alpha and its derivation
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The pthread_mutex_clocklock and pthread_mutex_timedlock have been converted
to support 64 bit time.
This change uses:
- New __futex_clocklock_wait64 (instead of lll_timedwait)
from ./sysdeps/nptl/futex-helpers.c and
- New __futex_clocklock64 function (instead of lll_clocklock)
- New futex_lock_pi64
defined in sysdeps/nptl/futex-internal.h
The pthread_mutex_{clock|timed}lock only accepts absolute time.
Moreover, there is no need to check for NULL passed as *abstime pointer to the
syscalls as those calls have exported symbols marked with __nonull attribute
for abstime.
Some architectures - namely x86, powerpc and s390 - do support lock elision.
For those - adjustments have been made in arch specific elision-*.c files
to use __futex_clocklock64 instead of lll_clocklock.
The __lll_lock_elision (aliased to __lll_clocklock_elision in e.g.
sysdeps/unix/sysv/linux/s390/elision-timed.c) just uses, in this patch
provided, __futex_clocklock64.
For systems with __TIMESIZE != 64 && __WORDSIZE == 32:
- Conversions between 64 bit time to 32 bit are necessary
- Redirection to pthread_mutex_{clock|timed}lock will provide support for 64
bit time
Build tests:
./src/scripts/build-many-glibcs.py glibcs
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
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It avoids regressions on possible future commands that might require
additional libc support. The downside is new commands added by newer
kernels will need further glibc support.
Checked on x86_64-linux-gnu and i686-linux-gnu (Linux v4.15 and v5.4).
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Both commands are Linux extensions where the third argument is either
a 'struct shminfo' (IPC_INFO) or a 'struct shm_info' (SHM_INFO) instead
of 'struct shmid_ds'. And their information does not contain any time
related fields, so there is no need to extra conversion for __IPC_TIME64.
The regression testcase checks for Linux specifix SysV ipc message
control extension. For SHM_INFO it tries to match the values against the
tunable /proc values and for MSG_STAT/MSG_STAT_ANY it check if the create\
shared memory is within the global list returned by the kernel.
Checked on x86_64-linux-gnu and on i686-linux-gnu (Linux v5.4 and on
Linux v4.15).
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Add CPU detection of Neoverse N2 and Neoverse V1, and select __memcpy_simd as
the memcpy/memmove ifunc.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
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It adds the missing new symbols from 8ed005daf0 and 589260cef8 (which
added versioned symbols for {f,l}stat{at}{64} and mknod{a}t) on some
libc.abilist ABIs.
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* sysdeps/mach/clock_gettime.c (__clock_gettime): Add support for
CLOCK_PROCESS_CPUTIME_ID and CLOCK_THREAD_CPUTIME_ID.
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It also decouple mknod{at} from xmknod{at}. The riscv32 ABI was added
on 2.33, so it is safe to remove the old __xmknot{at} symbols and just
provide the newer mknod{at} ones.
Checked with a build for all affected ABIs. I also checked on x86_64,
i686, powerpc, powerpc64le, sparcv9, sparc64, s390, and s390x.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
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A new struct __stat{64}_t64 type is added with the required
__timespec64 time definition. Only LFS is added, 64-bit time with
32-bit offsets is not supposed to be supported (no existing glibc
configuration supports such a combination). It is done with an extra
__NR_statx call plus a conversion to the new __stat{64}_t64 type.
The statx call is done only for 32-bit time_t ABIs.
Internally some extra routines to copy from/to struct stat{64}
to struct __stat{64} used on multiple implementations (stat, fstat,
lstat, and fstatat) are added on a extra implementation
(stat_t64_cp.c). Alse some extra routines to copy from statx to
__stat{64} is added on statx_cp.c.
Checked with a build for all affected ABIs. I also checked on x86_64,
i686, powerpc, powerpc64le, sparcv9, sparc64, s390, and s390x.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
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They are no interna uses anymore. The riscv32 ABI was added on 2.33,
so it is safe to remove the old __{f,l}stat{at} symbols and just
provide the newer {f,l}stat{at} ones.
Checked with a build for all affected ABIs. I also checked on x86_64,
i686, powerpc, powerpc64le, sparcv9, sparc64, s390, and s390x.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
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It implements all the required syscall for the all Linux kABIS on
fstatat{64} instead of calling fxstatat{64}.
On non-LFS implementation, it handles 3 cases:
1. New kABIs which uses generic pre 64-bit time Linux ABI (csky and
nios): it issues __NR_fstat64 plus handle the overflow on st_ino,
st_size, or st_blocks.
2. Old KABIs with old non-LFS support (arm, i386, hppa, m68k,
microblaze, mips32, s390, sh, powerpc, and sparc32): it issues
__NR_fstatat64 and convert the result to struct stat.
3. 64-bit kABI outliers (mips64 and mips64-n32): it issues
__NR_newfstatat and convert the result to struct stat.
The generic LFS implementation handles multiple cases:
1. XSTAT_IS_XSTAT64 being 1:
1.1. 64-bit kABI (aarch64, ia64, powerpc64*, s390x, riscv64, and
x86_64): it issues __NR_newfstatat.
1.2. 64-bit kABI outlier (alpha): it issues __NR_fstatat64.
1.3. 64-bit kABI outlier where struct stat64 does not match kernel
one (sparc64): it issues __NR_fstatat64 and convert the result
to struct stat64.
1.4. 32-bit kABI with default 64-bit time_t (arc, riscv32): it
issues __NR_statx and convert the result to struct stat64.
2. Old ABIs with XSTAT_IS_XSTAT64 being 0:
2.1. All kABIs with non-LFS support (arm, csky, i386, hppa, m68k,
microblaze, nios2, sh, powerpc32, and sparc32): it issues
__NR_fstatat64.
2.2. 64-bit kABI outliers (mips64 and mips64-n32): it issues
__NR_newfstatat and convert the result to struct stat64.
It allows to remove all the hidden definitions from the {f,l}xstat{64}
(some are still kept because Hurd requires it).
Checked with a build for all affected ABIs. I also checked on x86_64,
i686, powerpc, powerpc64le, sparcv9, sparc64, s390, and s390x.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
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Both fstatat and fstata64 calls the old fxstatat and fxstatat64
repectivelly with _STAT_VER, the one currently exported as default
for all ABIs.
Checked with a build for all affected ABIs. I also checked on x86_64,
i686, powerpc, powerpc64le, sparcv9, sparc64, s390, and s390x.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
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The common definitions are moved to a Linux generic stat.h while the
struct stat{64} definition are moved to a arch-specific struct_stat.h
header.
Checked with a build for all affected ABIs. I also checked on x86_64,
i686, powerpc, powerpc64le, sparcv9, sparc64, s390, and s390x.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
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This patch removes the mknod and mknodat static wrapper and add the
symbols on the libc with the expected names.
Both the prototypes of the internal symbol linked by the static
wrappers and the inline redirectors are also removed from the installed
sys/stat.h header file. The wrapper implementation license LGPL
exception is also removed since it is no longer statically linked to
binaries.
Internally the _STAT_VER* definitions are moved to the arch-specific
xstatver.h file.
Checked with a build for all affected ABIs. I also checked on x86_64,
i686, powerpc, powerpc64le, sparcv9, sparc64, s390, and s390x.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
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This patch removes the stat, stat64, lstat, lstat64, fstat, fstat64,
fstatat, and fstatat64 static wrapper and add the symbol on the libc
with the expected names.
Both the prototypes of the internal symbol linked by the static
wrappers and the inline redirectors are also removed from the installed
sys/stat.h header file. The wrapper implementation license LGPL
exception is also removed since it is no longer statically linked to
binaries.
Internally the _STAT_VER* definitions are moved to a arch-specific
xstatver.h file. The internal defines that redirects internals
{f}stat{at} to their {f}xstat{at} counterparts are removed for Linux
(!NO_RTLD_HIDDEN). Hurd still requires them since {f}stat{at} pulls
extra objects that makes the loader build fail otherwise (I haven't
dig into why exactly).
Checked with a build for all affected ABIs. I also checked on x86_64,
i686, powerpc, powerpc64le, sparcv9, sparc64, s390, and s390x.
Reviewed-by: Lukasz Majewski <lukma@denx.de>
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Add Fast Short REP CMP and SCA (FSRCS), Fast Short REP STO (FSRS) and
Fast Zero-Length REP MOV (FZLRM) support to <sys/platform/x86.h>.
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Add Intel HRESET support to <sys/platform/x86.h>.
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Add AVX-VNNI support to <sys/platform/x86.h>.
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Add AVX512_FP16 support to <sys/platform/x86.h>.
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Add Intel UINTR support to <sys/platform/x86.h>.
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In the current code, the function can easily obtain the information
on its own.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
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This allows more precise LD_DEBUG diagnostics.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
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It fixes the tst-cancelx{4,5} and tst-cancel24-{static} regression on
some platforms (arm and sparc32).
Checked on arm-linux-gnueabihf and sparcv9-linux-gnu.
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The generic version is parallel to _dl_writev. It cannot use
_dl_writev directly because the errno value needs to be obtained
under a lock.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
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Current systems do not have BSD terminals, so the fallback code in
posix_openpt/getpt does not do anything. Also remove the file system
check for /dev/pts. Current systems always have a devpts file system
mounted there if /dev/ptmx exists.
grantpt is now essentially a no-op. It only verifies that the
argument is a ptmx-descriptor. Therefore, this change indirectly
addresses bug 24941.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
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The EINVAL error code is mandated by POSIX and documented in the
manual. Also clean up the unlockpt implementation a bit, assuming
that TIOCSPTLCK is always defined.
Enhance login/tst-grantpt to cover unlockpt corner cases.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
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GCC 11 -Warray-bounds triggers invalid warnings when building
Linux timer_create.c:
../sysdeps/unix/sysv/linux/timer_create.c: In function '__timer_create_new':
../sysdeps/unix/sysv/linux/timer_create.c:83:17: warning: array subscript 'struct timer[0]' is partly outside array bounds of 'unsigned char[8]' [-Warray-bounds]
83 | newp->sigev_notify = (evp != NULL
| ^~
../sysdeps/unix/sysv/linux/timer_create.c:59:47: note: referencing an object of size 8 allocated by 'malloc'
59 | struct timer *newp = (struct timer *) malloc (offsetof (struct timer,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
60 | thrfunc));
| ~~~~~~~~~
The struct allocated for !SIGEV_THREAD timers only requires two 'int'
fields (sigev_notify and ktimerid) and the offsetof trick tries minimize
the memory usage by only allocation the required size. However,
although the resulting size is suffice for !SIGEV_THREAD time, accessing
the partially allocated object is error-prone and UB.
This patch fixes both issues by embedding the information whether
the timer if a SIGEV_THREAD in the returned 'timer_t'. For
!SIGEV_THREAD, the resulting 'timer_t' is the returned kernel timer
identifer (kernel_timer_t), while for SIGEV_THREAD it uses the fact
malloc returns at least _Alignof (max_align_t) pointers plus that
valid kernel_timer_t are always positive to set MSB bit of the returned
'timer_t' to indicate the timer handles a SIGEV_THREAD.
It allows to remove the memory allocation for !SIGEV_THREAD and also
remove the 'sigev_notify' field from 'struct timer'.
Checked on x86_64-linux-gnu and i686-linux-gnu.
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Replace Minumum/minumum in comments with Minimum/minimum.
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This patch fixes part of bug 26647 (-Werror=array-parameter error
building with GCC 11 because of __sigsetjmp being declared using an
array parameter in one header and a pointer parameter in another).
The fix is to split the struct __jmp_buf_tag definition out to a
separate bits/types/ header so it can be included in pthread.h, so
that pthread.h can declare __sigsetjmp with the type contents visible,
so can use an array (as in setjmp.h) rather than a pointer in the
declaration.
Note that several other build failures with GCC 11 remain. This does
not fix the jmp_buf-related -Wstringop-overflow errors (also discussed
in bug 26647), or -Warray-parameter errors for other functions (bug
26686), or -Warray-bounds errors (bug 26687).
Tested, with older compilers, natively for x86_64 and with
build-many-glibc.py for aarch64-linux-gnu. Tested with
build-many-glibcs.py with GCC mainline for aarch64-linux-gnu that this
gets past the -Warray-parameter issue for __sigsetjmp (with the next
build failure being the other one discussed in bug 26647).
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This is the helper function, which uses struct __timespec64
to provide 64 bit absolute time to futex syscalls.
The aim of this function is to move convoluted pre-processor
macro code from sysdeps/nptl/lowlevellock-futex.h to C
function in futex-internal.c
The futex_abstimed_wait64 function has been put into a separate
file on the purpose - to avoid issues apparent on the m68k
architecture related to small number of available registers (there
is not enough registers to put all necessary arguments in them if
the above function would be added to futex-internal.h with
__always_inline attribute).
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
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It avoids regressions on possible future commands that might require
additional libc support. The downside is new commands added by newer
kernels will need further glibc support.
Checked on x86_64-linux-gnu and i686-linux-gnu (Linux v4.15 and v5.4).
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Both commands are Linux extensions where the third argument is a
'struct msginfo' instead of 'struct msqid_ds' and its information
does not contain any time related fields (so there is no need to
extra conversion for __IPC_TIME64.
The regression testcase checks for Linux specifix SysV ipc message
control extension. For IPC_INFO/MSG_INFO it tries to match the values
against the tunable /proc values and for MSG_STAT/MSG_STAT_ANY it
check if the create message queue is within the global list returned
by the kernel.
Checked on x86_64-linux-gnu and on i686-linux-gnu (Linux v5.4 and on
Linux v4.15).
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It avoids regressions on possible future commands that might require
additional libc support. The downside is new commands added by newer
kernels will need further glibc support.
Checked on x86_64-linux-gnu and i686-linux-gnu (Linux v4.15 and v5.4).
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Handle SEM_STAT_ANY the same way as SEM_STAT so that the buffer argument
of SEM_STAT_ANY is properly passed to the kernel and back.
The regression testcase checks for Linux specifix SysV ipc message
control extension. For IPC_INFO/SEM_INFO it tries to match the values
against the tunable /proc values and for SEM_STAT/SEM_STAT_ANY it
check if the create message queue is within the global list returned
by the kernel.
Checked on x86_64-linux-gnu and on i686-linux-gnu (Linux v5.4 and on
Linux v4.15).
Co-authored-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
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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.
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Both powerpc64 and s390x provides semtimedop through __NR_ipc for
pre v5.1 kernel. Neither the y2038 support (7c437d3778) nor the
attempt to fix an issue for !__ASSUME_DIRECT_SYSVIPC_SYSCALLS
(aaa12e9ff0) took this in consideration.
This patch fixes it by issuing __NR_semtimedop_time64 iff it is
defined, otherwise __NR_semtimeop is issued if both
__ASSUME_DIRECT_SYSVIPC_SYSCALLS it set and __NR_semtimedop is
define, other __NR_ipc is used instead. To summarize:
1. For 32-bit architetures __NR_semtimedop_time64 is always
issued. The fallback is used only for !__ASSUME_TIME64_SYSCALLS
and it issues either __NR_ipc or __NR_semtimedop.
2. For 64-bit architecture with wire-up SysV syscall
(__ASSUME_DIRECT_SYSVIPC_SYSCALLS and __NR_semtimeop defined)
__NR_semtimeop is issued.
3. Otherwise __NR_ipc is used instead.
Checked on x86_64-linux-gnu, i686-linux-gnu (kernel 4.15 and 5.4),
powerpc64le (kernel 4.18), and s390x (kernel 4.12).
Reviewed-by: Matheus Castanho <msc@linux.ibm.com>
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This alias macro shall be moved to the beginning of the futex-internal.h
to be easily reused by other functions, which would support 64 bit time.
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
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This change provides proper spelling of 32 bit __futex_abstimed_wait_cancelable32
function
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
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It returns the string of the error constant, not its description (as
strerrordesc_np). To handle the Hurd error mapping, the ERR_MAP was
removed from errlist.h to errlist.c.
Also, the testcase test-strerr (added on 325081b9eb2) was not added
on the check build neither it builds correctly. This patch also
changed it to decouple from errlist.h, the expected return values
are added explicitly for both both strerrorname_np and strerrordesc_np
directly.
Checked on x86_64-linux-gnu and i686-linux-gnu. I also run a make
check for i686-gnu.
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The __x86_shared_non_temporal_threshold determines when memcpy on x86
uses non_temporal stores to avoid pushing other data out of the last
level cache.
This patch proposes to revert the calculation change made by H.J. Lu's
patch of June 2, 2017.
H.J. Lu's patch selected a threshold suitable for a single thread
getting maximum performance. It was tuned using the single threaded
large memcpy micro benchmark on an 8 core processor. The last change
changes the threshold from using 3/4 of one thread's share of the
cache to using 3/4 of the entire cache of a multi-threaded system
before switching to non-temporal stores. Multi-threaded systems with
more than a few threads are server-class and typically have many
active threads. If one thread consumes 3/4 of the available cache for
all threads, it will cause other active threads to have data removed
from the cache. Two examples show the range of the effect. John
McCalpin's widely parallel Stream benchmark, which runs in parallel
and fetches data sequentially, saw a 20% slowdown with this patch on
an internal system test of 128 threads. This regression was discovered
when comparing OL8 performance to OL7. An example that compares
normal stores to non-temporal stores may be found at
https://vgatherps.github.io/2018-09-02-nontemporal/. A simple test
shows performance loss of 400 to 500% due to a failure to use
nontemporal stores. These performance losses are most likely to occur
when the system load is heaviest and good performance is critical.
The tunable x86_non_temporal_threshold can be used to override the
default for the knowledgable user who really wants maximum cache
allocation to a single thread in a multi-threaded system.
The manual entry for the tunable has been expanded to provide
more information about its purpose.
modified: sysdeps/x86/cacheinfo.c
modified: manual/tunables.texi
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