Path: csiph.com!1.us.feeder.erje.net!feeder.erje.net!2.eu.feeder.erje.net!news.roellig-ltd.de!open-news-network.org!weretis.net!feeder4.news.weretis.net!news.unit0.net!news.panservice.it!bofh.it!news.nic.it!robomod From: Daniel Bristot de Oliveira Newsgroups: linux.kernel Subject: Re: [PATCH] sched/deadline: Add missing update_rq_clock() in dl_task_timer() Date: Wed, 15 Mar 2017 11:50:02 +0100 Message-ID: References:

X-Google-Dkim-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:cc:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=lDmtrHS3+1vrTV6qVk4MrN08rfWRdIGzVeWQqVsDHKE=; b=d0zCNUEPbD8e79p43M0+BEk4rnc+q3DYF+gOg1iQUKBUQraFPNjD/rU2kGUuS9KlYO kGZ2Ged7d3m8BCUIYuM3SRQMtF7cXmwqUe64h6Fd6YFghN2hvx2/MgVTHfC9iVWN4Tqo J+//3GZZqpoYZiMc+1AUZJQ5tnpLUGv4UncaN7wjaGEOjEAMYw6bVLvE1AE9Fs1ro0dI xHUbGkA1re/Gt5He+WlYD0CK98xQS5cdlzGuWOiCj0A6DDDw++DB4BOPBoMOhD6Fw86U bHgsJHAs4SVt0CvFg632jw2wDf1kiFzJjmfLumg1KRO1gLQGkbZ1ePS2wX7SGBSWnijb i34Q== X-Gm-Message-State: AFeK/H2Lq1QWWpQHMfVHr/Tohp50HnB57va9jLMyws8I71ZCGqs6yR/vwFb7L+FxNORDC7H4 X-Received: by 10.55.12.67 with SMTP id 64mr1893341qkm.291.1489574665943; Wed, 15 Mar 2017 03:44:25 -0700 (PDT) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: robomod@news.nic.it List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Approved: robomod@news.nic.it Lines: 52 Organization: linux.* mail to news gateway X-Original-Cc: Ingo Molnar , Peter Zijlstra , Wanpeng Li , Juri Lelli , Thomas Gleixner , Matt Fleming X-Original-Date: Wed, 15 Mar 2017 11:44:22 +0100 X-Original-Message-ID: <7b012738-bc10-6ba4-b576-a13175d09a4a@redhat.com> X-Original-References: <1488865888-15894-1-git-send-email-wanpeng.li@hotmail.com> X-Original-Sender: linux-kernel-owner@vger.kernel.org Xref: csiph.com linux.kernel:1601258 On 03/15/2017 08:53 AM, Wanpeng Li wrote: > Ping, :) > 2017-03-07 13:51 GMT+08:00 Wanpeng Li : >> From: Wanpeng Li >> >> The following warning can be triggered by hot-unplugging the CPU >> on which an active SCHED_DEADLINE task is running on: >> >> ------------[ cut here ]------------ >> WARNING: CPU: 7 PID: 0 at kernel/sched/sched.h:833 replenish_dl_entity+0x71e/0xc40 >> rq->clock_update_flags < RQCF_ACT_SKIP >> CPU: 7 PID: 0 Comm: swapper/7 Tainted: G B 4.11.0-rc1+ #24 >> Hardware name: LENOVO ThinkCentre M8500t-N000/SHARKBAY, BIOS FBKTC1AUS 02/16/2016 >> Call Trace: >> >> dump_stack+0x85/0xc4 >> __warn+0x172/0x1b0 >> warn_slowpath_fmt+0xb4/0xf0 >> ? __warn+0x1b0/0x1b0 >> ? debug_check_no_locks_freed+0x2c0/0x2c0 >> ? cpudl_set+0x3d/0x2b0 >> replenish_dl_entity+0x71e/0xc40 >> enqueue_task_dl+0x2ea/0x12e0 >> ? dl_task_timer+0x777/0x990 >> ? __hrtimer_run_queues+0x270/0xa50 >> dl_task_timer+0x316/0x990 >> ? enqueue_task_dl+0x12e0/0x12e0 >> ? enqueue_task_dl+0x12e0/0x12e0 >> __hrtimer_run_queues+0x270/0xa50 >> ? hrtimer_cancel+0x20/0x20 >> ? hrtimer_interrupt+0x119/0x600 >> hrtimer_interrupt+0x19c/0x600 >> ? trace_hardirqs_off+0xd/0x10 >> local_apic_timer_interrupt+0x74/0xe0 >> smp_apic_timer_interrupt+0x76/0xa0 >> apic_timer_interrupt+0x93/0xa0 >> >> The DL task will be migrated to a suitable later deadline rq once the DL >> timer fires and currnet rq is offline. The rq clock of the new rq should >> be updated. This patch fixes it by updating the rq clock after holding >> the new rq's rq lock. >> >> Cc: Juri Lelli >> Cc: Peter Zijlstra >> Cc: Ingo Molnar >> Cc: Thomas Gleixner >> Cc: Matt Fleming >> Signed-off-by: Wanpeng Li Reviewed-by: Daniel Bristot de Oliveira -- Daniel