From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753106Ab0A1WEO (ORCPT ); Thu, 28 Jan 2010 17:04:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751465Ab0A1WEN (ORCPT ); Thu, 28 Jan 2010 17:04:13 -0500 Received: from smtp.mujha-vel.cz ([81.30.225.246]:53947 "EHLO smtp.mujha-vel.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750759Ab0A1WEM (ORCPT ); Thu, 28 Jan 2010 17:04:12 -0500 From: Jiri Slaby To: akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, jirislaby@gmail.com, Ingo Molnar , Peter Zijlstra Subject: [PATCH 1/2] core: posix-cpu-timers, cleanup rlimits usage Date: Thu, 28 Jan 2010 23:04:07 +0100 Message-Id: <1264716248-25112-1-git-send-email-jslaby@suse.cz> X-Mailer: git-send-email 1.6.6.1 In-Reply-To: <4B612D57.4080604@gmail.com> References: <4B612D57.4080604@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Rebased on the top of mmotm 2010-01-28-01-36. Hopefully this time it will work out. -- Fetch rlimit (both hard and soft) values only once and work on them. It removes many accesses through sig structure and makes the code cleaner. Mostly a preparation for writable resource limits support. Signed-off-by: Jiri Slaby Cc: Ingo Molnar Cc: Peter Zijlstra --- kernel/posix-cpu-timers.c | 32 +++++++++++++++++--------------- 1 files changed, 17 insertions(+), 15 deletions(-) diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index ffba8f4..417fe38 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c @@ -917,6 +917,7 @@ static void check_thread_timers(struct task_struct *tsk, int maxfire; struct list_head *timers = tsk->cpu_timers; struct signal_struct *const sig = tsk->signal; + unsigned long soft; maxfire = 20; tsk->cputime_expires.prof_exp = cputime_zero; @@ -965,9 +966,9 @@ static void check_thread_timers(struct task_struct *tsk, /* * Check for the special case thread timers. */ - if (sig->rlim[RLIMIT_RTTIME].rlim_cur != RLIM_INFINITY) { + soft = sig->rlim[RLIMIT_RTTIME].rlim_cur; + if (soft != RLIM_INFINITY) { unsigned long hard = sig->rlim[RLIMIT_RTTIME].rlim_max; - unsigned long *soft = &sig->rlim[RLIMIT_RTTIME].rlim_cur; if (hard != RLIM_INFINITY && tsk->rt.timeout > DIV_ROUND_UP(hard, USEC_PER_SEC/HZ)) { @@ -978,14 +979,13 @@ static void check_thread_timers(struct task_struct *tsk, __group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk); return; } - if (tsk->rt.timeout > DIV_ROUND_UP(*soft, USEC_PER_SEC/HZ)) { + if (tsk->rt.timeout > DIV_ROUND_UP(soft, USEC_PER_SEC/HZ)) { /* * At the soft limit, send a SIGXCPU every second. */ - if (sig->rlim[RLIMIT_RTTIME].rlim_cur - < sig->rlim[RLIMIT_RTTIME].rlim_max) { - sig->rlim[RLIMIT_RTTIME].rlim_cur += - USEC_PER_SEC; + if (soft < hard) { + soft += USEC_PER_SEC; + sig->rlim[RLIMIT_RTTIME].rlim_cur = soft; } printk(KERN_INFO "RT Watchdog Timeout: %s[%d]\n", @@ -1070,6 +1070,7 @@ static void check_process_timers(struct task_struct *tsk, unsigned long long sum_sched_runtime, sched_expires; struct list_head *timers = sig->cpu_timers; struct task_cputime cputime; + unsigned long soft; /* * Collect the current process totals. @@ -1129,11 +1130,12 @@ static void check_process_timers(struct task_struct *tsk, SIGPROF); check_cpu_itimer(tsk, &sig->it[CPUCLOCK_VIRT], &virt_expires, utime, SIGVTALRM); - - if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { + soft = sig->rlim[RLIMIT_CPU].rlim_cur; + if (soft != RLIM_INFINITY) { unsigned long psecs = cputime_to_secs(ptime); + unsigned long hard = sig->rlim[RLIMIT_CPU].rlim_max; cputime_t x; - if (psecs >= sig->rlim[RLIMIT_CPU].rlim_max) { + if (psecs >= hard) { /* * At the hard limit, we just die. * No need to calculate anything else now. @@ -1141,17 +1143,17 @@ static void check_process_timers(struct task_struct *tsk, __group_send_sig_info(SIGKILL, SEND_SIG_PRIV, tsk); return; } - if (psecs >= sig->rlim[RLIMIT_CPU].rlim_cur) { + if (psecs >= soft) { /* * At the soft limit, send a SIGXCPU every second. */ __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk); - if (sig->rlim[RLIMIT_CPU].rlim_cur - < sig->rlim[RLIMIT_CPU].rlim_max) { - sig->rlim[RLIMIT_CPU].rlim_cur++; + if (soft < hard) { + soft++; + sig->rlim[RLIMIT_CPU].rlim_cur = soft; } } - x = secs_to_cputime(sig->rlim[RLIMIT_CPU].rlim_cur); + x = secs_to_cputime(soft); if (cputime_eq(prof_expires, cputime_zero) || cputime_lt(x, prof_expires)) { prof_expires = x; -- 1.6.6.1