From patchwork Fri Feb 8 18:39:06 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella Netto X-Patchwork-Id: 31363 Received: (qmail 76769 invoked by alias); 8 Feb 2019 18:39:22 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 76747 invoked by uid 89); 8 Feb 2019 18:39:22 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-26.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_PASS autolearn=ham version=3.3.2 spammy= X-HELO: mail-qk1-f193.google.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:subject:date:message-id:in-reply-to:references; bh=0LkF4LPe7oJEE1zmRiqT7eCqVrLitPnZZJdGOoLNDfM=; b=tAoIuTRrYoecmvftLQ71O/DoGVcFxBb/s1lOdTRi4ltawoNqQUK58CoTFwU1a1bI6X KbMNE7tyqESlYgaZzuHJUrQHEiGrHbZx5ui3Pk4AsBqNHf6kOhtgsxajFsiFzzKI5Exv bUNJXURHi44Ef5jxLgGb+STqmEtB+ZA40qhj+1qcWVW7cxDCgPFyq3/pkRpEzzEgN0Yy mW9OkmdgJ25GhH6UsUX38rfnkPUdfwMuH9gsuIQRA9592d8+crY9dISENv97+ZuCbycA gcPMw+P0aFNIJlvZYmQ5t+RV+rM8Z82yuf/RBUT50Nr0fJUdfVZhLNHYnEqtaV0IBnAW Abmg== Return-Path: From: Adhemerval Zanella To: libc-alpha@sourceware.org Subject: [PATCH 2/6] linux: Assume clock_getres CLOCK_{PROCESS, THREAD}_CPUTIME_ID Date: Fri, 8 Feb 2019 16:39:06 -0200 Message-Id: <20190208183910.30799-2-adhemerval.zanella@linaro.org> In-Reply-To: <20190208183910.30799-1-adhemerval.zanella@linaro.org> References: <20190208183910.30799-1-adhemerval.zanella@linaro.org> 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. --- sysdeps/unix/sysv/linux/ia64/has_cpuclock.c | 51 --------------------- sysdeps/unix/sysv/linux/ia64/sysconf.c | 36 ++++++++++++--- sysdeps/unix/sysv/linux/sysconf.c | 46 ++++++------------- 3 files changed, 44 insertions(+), 89 deletions(-) delete mode 100644 sysdeps/unix/sysv/linux/ia64/has_cpuclock.c 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 - . */ - -#include -#include -#include -#include -#include -#include - -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 . */ -#include #include #include #include - - -#include "has_cpuclock.c" -#define HAS_CPUCLOCK(name) (has_cpuclock () ? _POSIX_VERSION : -1) - +#include + +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 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;