From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-20.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id AED89C4338F for ; Tue, 10 Aug 2021 16:02:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 939C7610A8 for ; Tue, 10 Aug 2021 16:02:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229493AbhHJQDJ (ORCPT ); Tue, 10 Aug 2021 12:03:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58004 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231767AbhHJQCj (ORCPT ); Tue, 10 Aug 2021 12:02:39 -0400 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EEA37C0613C1; Tue, 10 Aug 2021 09:02:16 -0700 (PDT) Date: Tue, 10 Aug 2021 16:02:14 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1628611335; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WZA0WNmeYMONHKWsLus3V1EUHxpkbYooY2IMzfbt5ck=; b=kXcrVWXBggoCbXblx1hS69OcnvGtaQGdKR0anrcgGZW/fj+HvYmjN93X7g8yq/x/J/jWvt 7VNXZ6hAzx2YIGordmv6VtaWkwDIyfpfz8rMUcfcU6gYR8fwWshkgQpZKeLik7/kYkNXdE 3NVxrXY0Ap/SnivmGSU/mMT9ML0fTQZxVYtlGW5kZhlWyXOYWda6e3tjl29eL+9DUCa6Gi o3k+urz1ebf7AM+Gau13l4G4jO93XfTDuae4gdZA7C+Uu+snci2+3x/ShE7YcB6z0Nsdip khHxT7/hGxQ70dX6dg2MJrJ/xMCnKNerM2eiMdCRtqrhFnvSe1/mEmYV9zJwaQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1628611335; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WZA0WNmeYMONHKWsLus3V1EUHxpkbYooY2IMzfbt5ck=; b=MP4rN9y+wQq+Ve1V6i26raOWAq/gVWZAwHol2hBws/82/METvOy1ZIyQLvcjxcUl4nvV4e leYBS4L63s2bESDQ== From: "tip-bot2 for Thomas Gleixner" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: timers/core] timekeeping: Distangle resume and clock-was-set events Cc: Thomas Gleixner , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20210713135158.488853478@linutronix.de> References: <20210713135158.488853478@linutronix.de> MIME-Version: 1.0 Message-ID: <162861133485.395.9303310350677655795.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the timers/core branch of tip: Commit-ID: a761a67f591a8c7476c30bb20ed0f09fdfb1a704 Gitweb: https://git.kernel.org/tip/a761a67f591a8c7476c30bb20ed0f09fdfb1a704 Author: Thomas Gleixner AuthorDate: Tue, 13 Jul 2021 15:39:51 +02:00 Committer: Thomas Gleixner CommitterDate: Tue, 10 Aug 2021 17:57:23 +02:00 timekeeping: Distangle resume and clock-was-set events Resuming timekeeping is a clock-was-set event and uses the clock-was-set notification mechanism. This is in the way of making the clock-was-set update for hrtimers selective so unnecessary IPIs are avoided when a CPU base does not have timers queued which are affected by the clock setting. Distangle it by invoking hrtimer_resume() on each unfreezing CPU and invoke the new timerfd_resume() function from timekeeping_resume() which is the only place where this is needed. Rename hrtimer_resume() to hrtimer_resume_local() to reflect the change. With this the clock_was_set*() functions are not longer required to IPI all CPUs unconditionally and can get some smarts to avoid them. Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20210713135158.488853478@linutronix.de --- include/linux/hrtimer.h | 1 - kernel/time/hrtimer.c | 15 ++++++--------- kernel/time/tick-common.c | 7 +++++++ kernel/time/tick-internal.h | 2 ++ kernel/time/timekeeping.c | 4 +++- 5 files changed, 18 insertions(+), 11 deletions(-) diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index 253c6e2..0ee1401 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -354,7 +354,6 @@ extern void timerfd_resume(void); static inline void timerfd_clock_was_set(void) { } static inline void timerfd_resume(void) { } #endif -extern void hrtimers_resume(void); DECLARE_PER_CPU(struct tick_device, tick_cpu_device); diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 214fd65..68e56f0 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -900,8 +900,8 @@ static void clock_was_set_work(struct work_struct *work) static DECLARE_WORK(hrtimer_work, clock_was_set_work); /* - * Called from timekeeping and resume code to reprogram the hrtimer - * interrupt device on all cpus and to notify timerfd. + * Called from timekeeping code to reprogram the hrtimer interrupt device + * on all cpus and to notify timerfd. */ void clock_was_set_delayed(void) { @@ -909,18 +909,15 @@ void clock_was_set_delayed(void) } /* - * During resume we might have to reprogram the high resolution timer - * interrupt on all online CPUs. However, all other CPUs will be - * stopped with IRQs interrupts disabled so the clock_was_set() call - * must be deferred. + * Called during resume either directly from via timekeeping_resume() + * or in the case of s2idle from tick_unfreeze() to ensure that the + * hrtimers are up to date. */ -void hrtimers_resume(void) +void hrtimers_resume_local(void) { lockdep_assert_irqs_disabled(); /* Retrigger on the local CPU */ retrigger_next_event(NULL); - /* And schedule a retrigger for all others */ - clock_was_set_delayed(); } /* diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c index d663249..4678935 100644 --- a/kernel/time/tick-common.c +++ b/kernel/time/tick-common.c @@ -470,6 +470,13 @@ void tick_resume_local(void) else tick_resume_oneshot(); } + + /* + * Ensure that hrtimers are up to date and the clockevents device + * is reprogrammed correctly when high resolution timers are + * enabled. + */ + hrtimers_resume_local(); } /** diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h index cd610fa..22de98c 100644 --- a/kernel/time/tick-internal.h +++ b/kernel/time/tick-internal.h @@ -168,3 +168,5 @@ void timer_clear_idle(void); void clock_was_set(void); void clock_was_set_delayed(void); + +void hrtimers_resume_local(void); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 8a364aa..c8a9b9e 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1810,8 +1810,10 @@ void timekeeping_resume(void) touch_softlockup_watchdog(); + /* Resume the clockevent device(s) and hrtimers */ tick_resume(); - hrtimers_resume(); + /* Notify timerfd as resume is equivalent to clock_was_set() */ + timerfd_resume(); } int timekeeping_suspend(void)