diff options
author | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2019-01-16 17:30:07 +0000 |
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committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2019-01-29 18:06:46 +0000 |
commit | f344827c038f865744389ee12b7022f9a9c90251 (patch) | |
tree | 021eb963d12222e36a9ae2b43e4ec82b43857c64 | |
parent | 408e23c740b074d606a1233e97619c04c50a7ad8 (diff) | |
download | glibc-f344827c038f865744389ee12b7022f9a9c90251.tar.gz |
linux: Assume CLOCK_{PROCESS,THREAD}_CPUTIME_ID
This patch assumes that clock_getres syscall always support
CLOCK_PROCESS_CPUTIME_ID and CLOCK_THREAD_CPUTIME_ID, so there is no need
to fallback to hp-timing support for _SC_MONOTONIC_CLOCK. This allows
simplify the sysconf support to always use the syscall.
The ia64 implementation is also simplified and consolidate in one file.
Checked on aarch64-linux-gnu, x86_64-linux-gnu, and i686-linux-gnu.
* sysdeps/unix/sysv/linux/ia64/has_cpuclock.c: Remove file.
* sysdeps/unix/sysv/linux/ia64/sysconf.c (ia64_check_cpuclock): New
function.
* sysdeps/unix/sysv/linux/sysconf.c (has_cpuclock): Remove function.
(check_clock_getres): New function.
(__sysconf): Use check_clock_getres instead of has_cpuclock.
-rw-r--r-- | sysdeps/unix/sysv/linux/ia64/has_cpuclock.c | 51 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/ia64/sysconf.c | 36 | ||||
-rw-r--r-- | sysdeps/unix/sysv/linux/sysconf.c | 46 |
3 files changed, 44 insertions, 89 deletions
diff --git a/sysdeps/unix/sysv/linux/ia64/has_cpuclock.c b/sysdeps/unix/sysv/linux/ia64/has_cpuclock.c deleted file mode 100644 index b3afb37f8b..0000000000 --- a/sysdeps/unix/sysv/linux/ia64/has_cpuclock.c +++ /dev/null @@ -1,51 +0,0 @@ -/* Copyright (C) 2000-2019 Free Software Foundation, Inc. - This file is part of the GNU C Library. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - <http://www.gnu.org/licenses/>. */ - -#include <errno.h> -#include <fcntl.h> -#include <unistd.h> -#include <sys/stat.h> -#include <sys/types.h> -#include <not-cancel.h> - -static int itc_usable; - -static int -has_cpuclock (void) -{ - if (__builtin_expect (itc_usable == 0, 0)) - { - int newval = 1; - int fd = __open_nocancel ("/proc/sal/itc_drift", O_RDONLY); - if (__builtin_expect (fd != -1, 1)) - { - char buf[16]; - /* We expect the file to contain a single digit followed by - a newline. If the format changes we better not rely on - the file content. */ - if (__read_nocancel (fd, buf, sizeof buf) != 2 - || buf[0] != '0' || buf[1] != '\n') - newval = -1; - - __close_nocancel_nostatus (fd); - } - - itc_usable = newval; - } - - return itc_usable; -} diff --git a/sysdeps/unix/sysv/linux/ia64/sysconf.c b/sysdeps/unix/sysv/linux/ia64/sysconf.c index ef75322f1f..48bb008f50 100644 --- a/sysdeps/unix/sysv/linux/ia64/sysconf.c +++ b/sysdeps/unix/sysv/linux/ia64/sysconf.c @@ -16,15 +16,39 @@ License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ -#include <assert.h> #include <stdbool.h> #include <stdlib.h> #include <unistd.h> - - -#include "has_cpuclock.c" -#define HAS_CPUCLOCK(name) (has_cpuclock () ? _POSIX_VERSION : -1) - +#include <not-cancel.h> + +static bool itc_usable; + +static bool +ia64_check_cpuclock (void) +{ + if (__glibc_unlikely (itc_usable == 0)) + { + int newval = true; + int fd = __open_nocancel ("/proc/sal/itc_drift", O_RDONLY); + if (__glibc_likely (fd != -1)) + { + char buf[16]; + /* We expect the file to contain a single digit followed by + a newline. If the format changes we better not rely on + the file content. */ + if (__read_nocancel (fd, buf, sizeof buf) != 2 + || buf[0] != '0' || buf[1] != '\n') + newval = false; + + __close_nocancel_nostatus (fd); + } + + itc_usable = newval; + } + + return itc_usable; +} +#define HAS_CPUCLOCK(name) (ia64_check_cpuclock () ? _POSIX_VERSION : -1) /* Now the generic Linux version. */ #include <sysdeps/unix/sysv/linux/sysconf.c> diff --git a/sysdeps/unix/sysv/linux/sysconf.c b/sysdeps/unix/sysv/linux/sysconf.c index 4b297ba35f..b870a21810 100644 --- a/sysdeps/unix/sysv/linux/sysconf.c +++ b/sysdeps/unix/sysv/linux/sysconf.c @@ -35,31 +35,19 @@ static long int posix_sysconf (int name); -#ifndef HAS_CPUCLOCK static long int -has_cpuclock (int name) +check_clock_getres (clockid_t clk_id) { -# if defined __NR_clock_getres || HP_TIMING_AVAIL - /* If we have HP_TIMING, we will fall back on that if the system - call does not work, so we support it either way. */ -# if !HP_TIMING_AVAIL - /* Check using the clock_getres system call. */ struct timespec ts; INTERNAL_SYSCALL_DECL (err); - int r = INTERNAL_SYSCALL (clock_getres, err, 2, - (name == _SC_CPUTIME - ? CLOCK_PROCESS_CPUTIME_ID - : CLOCK_THREAD_CPUTIME_ID), - &ts); + int r = INTERNAL_SYSCALL_CALL (clock_getres, err, clk_id, &ts); if (INTERNAL_SYSCALL_ERROR_P (r, err)) return -1; -# endif return _POSIX_VERSION; -# else - return -1; -# endif } -# define HAS_CPUCLOCK(name) has_cpuclock (name) + +#ifndef HAS_CPUCLOCK +# define HAS_CPUCLOCK(name) check_clock_getres (name) #endif @@ -71,29 +59,22 @@ __sysconf (int name) switch (name) { - struct rlimit rlimit; -#ifdef __NR_clock_getres case _SC_MONOTONIC_CLOCK: - /* Check using the clock_getres system call. */ - { - struct timespec ts; - INTERNAL_SYSCALL_DECL (err); - int r; - r = INTERNAL_SYSCALL (clock_getres, err, 2, CLOCK_MONOTONIC, &ts); - return INTERNAL_SYSCALL_ERROR_P (r, err) ? -1 : _POSIX_VERSION; - } -#endif + return check_clock_getres (CLOCK_MONOTONIC); case _SC_CPUTIME: + return HAS_CPUCLOCK (CLOCK_PROCESS_CPUTIME_ID); case _SC_THREAD_CPUTIME: - return HAS_CPUCLOCK (name); + return HAS_CPUCLOCK (CLOCK_THREAD_CPUTIME_ID); - case _SC_ARG_MAX: + case _SC_ARG_MAX: { + struct rlimit rlimit; /* Use getrlimit to get the stack limit. */ if (__getrlimit (RLIMIT_STACK, &rlimit) == 0) return MAX (legacy_ARG_MAX, rlimit.rlim_cur / 4); return legacy_ARG_MAX; + } break; case _SC_NGROUPS_MAX: /* Try to read the information from the /proc/sys/kernel/ngroups_max @@ -101,13 +82,14 @@ __sysconf (int name) procfname = "/proc/sys/kernel/ngroups_max"; break; - case _SC_SIGQUEUE_MAX: + case _SC_SIGQUEUE_MAX: { + struct rlimit rlimit; if (__getrlimit (RLIMIT_SIGPENDING, &rlimit) == 0) return rlimit.rlim_cur; /* The /proc/sys/kernel/rtsig-max file contains the answer. */ procfname = "/proc/sys/kernel/rtsig-max"; - break; + } break; default: break; |