From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f179.google.com (mail-pd0-f179.google.com [209.85.192.179]) by kanga.kvack.org (Postfix) with ESMTP id BFF1F6B0035 for ; Mon, 4 Aug 2014 05:26:49 -0400 (EDT) Received: by mail-pd0-f179.google.com with SMTP id ft15so9340068pdb.38 for ; Mon, 04 Aug 2014 02:26:49 -0700 (PDT) Received: from smtp.codeaurora.org (smtp.codeaurora.org. [198.145.11.231]) by mx.google.com with ESMTPS id be2si16936644pbb.236.2014.08.04.02.26.48 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 04 Aug 2014 02:26:48 -0700 (PDT) Message-ID: <53DF51D2.4090002@codeaurora.org> Date: Mon, 04 Aug 2014 14:56:42 +0530 From: Chintan Pandya MIME-Version: 1.0 Subject: Re: [PATCH v3 1/2] timer: provide an api for deferrable timeout References: <1406793591-26793-2-git-send-email-cpandya@codeaurora.org> In-Reply-To: <1406793591-26793-2-git-send-email-cpandya@codeaurora.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Chintan Pandya Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Thomas Gleixner , John Stultz , Peter Zijlstra , Ingo Molnar , Hugh Dickins Ping !! Anything open for me to do here ? On 07/31/2014 01:29 PM, Chintan Pandya wrote: > schedule_timeout wakes up the CPU from IDLE state. For some use cases it > is not desirable, hence introduce a convenient API > (schedule_timeout_deferrable_interruptible) on similar pattern which uses > a deferrable timer. > > Signed-off-by: Chintan Pandya > Cc: Thomas Gleixner > Cc: John Stultz > Cc: Peter Zijlstra > Cc: Ingo Molnar > Cc: Hugh Dickins > --- > Changes: > > V2-->V3: > - Big comment moved from static function to exported function > - Using __setup_timer_on_stack for better readability > > V2: > - this patch has been newly introduced in patch v2 > > include/linux/sched.h | 2 ++ > kernel/time/timer.c | 73 +++++++++++++++++++++++++++++++-------------------- > 2 files changed, 47 insertions(+), 28 deletions(-) > > diff --git a/include/linux/sched.h b/include/linux/sched.h > index 89f531e..10b154e 100644 > --- a/include/linux/sched.h > +++ b/include/linux/sched.h > @@ -377,6 +377,8 @@ extern int in_sched_functions(unsigned long addr); > #define MAX_SCHEDULE_TIMEOUT LONG_MAX > extern signed long schedule_timeout(signed long timeout); > extern signed long schedule_timeout_interruptible(signed long timeout); > +extern signed long > +schedule_timeout_deferrable_interruptible(signed long timeout); > extern signed long schedule_timeout_killable(signed long timeout); > extern signed long schedule_timeout_uninterruptible(signed long timeout); > asmlinkage void schedule(void); > diff --git a/kernel/time/timer.c b/kernel/time/timer.c > index aca5dfe..f4c4082 100644 > --- a/kernel/time/timer.c > +++ b/kernel/time/timer.c > @@ -1431,33 +1431,8 @@ static void process_timeout(unsigned long __data) > wake_up_process((struct task_struct *)__data); > } > > -/** > - * schedule_timeout - sleep until timeout > - * @timeout: timeout value in jiffies > - * > - * Make the current task sleep until @timeout jiffies have > - * elapsed. The routine will return immediately unless > - * the current task state has been set (see set_current_state()). > - * > - * You can set the task state as follows - > - * > - * %TASK_UNINTERRUPTIBLE - at least @timeout jiffies are guaranteed to > - * pass before the routine returns. The routine will return 0 > - * > - * %TASK_INTERRUPTIBLE - the routine may return early if a signal is > - * delivered to the current task. In this case the remaining time > - * in jiffies will be returned, or 0 if the timer expired in time > - * > - * The current task state is guaranteed to be TASK_RUNNING when this > - * routine returns. > - * > - * Specifying a @timeout value of %MAX_SCHEDULE_TIMEOUT will schedule > - * the CPU away without a bound on the timeout. In this case the return > - * value will be %MAX_SCHEDULE_TIMEOUT. > - * > - * In all cases the return value is guaranteed to be non-negative. > - */ > -signed long __sched schedule_timeout(signed long timeout) > +static signed long > +__sched __schedule_timeout(signed long timeout, unsigned long flag) > { > struct timer_list timer; > unsigned long expire; > @@ -1493,7 +1468,9 @@ signed long __sched schedule_timeout(signed long timeout) > > expire = timeout + jiffies; > > - setup_timer_on_stack(&timer, process_timeout, (unsigned long)current); > + __setup_timer_on_stack(&timer, process_timeout, (unsigned long)current, > + flag); > + > __mod_timer(&timer, expire, false, TIMER_NOT_PINNED); > schedule(); > del_singleshot_timer_sync(&timer); > @@ -1506,12 +1483,52 @@ signed long __sched schedule_timeout(signed long timeout) > out: > return timeout< 0 ? 0 : timeout; > } > + > +/** > + * schedule_timeout - sleep until timeout > + * @timeout: timeout value in jiffies > + * > + * Make the current task sleep until @timeout jiffies have > + * elapsed. The routine will return immediately unless > + * the current task state has been set (see set_current_state()). > + * > + * You can set the task state as follows - > + * > + * %TASK_UNINTERRUPTIBLE - at least @timeout jiffies are guaranteed to > + * pass before the routine returns. The routine will return 0 > + * > + * %TASK_INTERRUPTIBLE - the routine may return early if a signal is > + * delivered to the current task. In this case the remaining time > + * in jiffies will be returned, or 0 if the timer expired in time > + * > + * The current task state is guaranteed to be TASK_RUNNING when this > + * routine returns. > + * > + * Specifying a @timeout value of %MAX_SCHEDULE_TIMEOUT will schedule > + * the CPU away without a bound on the timeout. In this case the return > + * value will be %MAX_SCHEDULE_TIMEOUT. > + * > + * In all cases the return value is guaranteed to be non-negative. > + */ > +signed long __sched schedule_timeout(signed long timeout) > +{ > + return __schedule_timeout(timeout, 0); > +} > EXPORT_SYMBOL(schedule_timeout); > > /* > * We can use __set_current_state() here because schedule_timeout() calls > * schedule() unconditionally. > */ > + > +signed long > +__sched schedule_timeout_deferrable_interruptible(signed long timeout) > +{ > + __set_current_state(TASK_INTERRUPTIBLE); > + return __schedule_timeout(timeout, TIMER_DEFERRABLE); > +} > +EXPORT_SYMBOL(schedule_timeout_deferrable_interruptible); > + > signed long __sched schedule_timeout_interruptible(signed long timeout) > { > __set_current_state(TASK_INTERRUPTIBLE); -- Chintan Pandya QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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