From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E244718623 for ; Wed, 3 Jan 2024 08:09:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="beUiVz5c" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6D8E5C433C7; Wed, 3 Jan 2024 08:09:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1704269345; bh=/P93iDWx0rUgDH9n+aFD3T8XY72jOetnP/Drn34JroI=; h=From:To:Cc:Subject:Date:From; b=beUiVz5cN9puQyNHLSi1W8HtLbj0mt8+Oe8KQOvTgF5f+hxaLd8Qn3fvvWREInjEB yQrg1j/ItpNZLzHW369EOdoi8yPtgAQgl4Z3L9vD4EAincXAYH5fbcXEDr7NIEXtzg A0b+2uXr9gxA/2Bdp62YyhZfaU/07rn+iCLZonqEGZTX7FeQy5gZVA5NoIArOBYegm Tdi+UEJHpA1pOWeErT5W6JR5L7YW+rHQ0VFCouwGrNSfILL+c1OlXKLsL1pPAn8e4c qJ7kQcYry1oFaN3ppL0uT9ghFec8T2ZjgNS6qZs1zA5TT6+9gOXGSFK1UWaJmiOMj/ 15JMMtqnFU9MA== From: alexs@kernel.org To: Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Valentin Schneider , linux-kernel@vger.kernel.org Cc: curuwang@tencent.com, Alex Shi Subject: [PATCH v2] sched/stat: correct the task blocking state Date: Wed, 3 Jan 2024 16:10:42 +0800 Message-ID: <20240103081042.1549189-1-alexs@kernel.org> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Alex Shi The commit 80ed87c8a9ca ("sched/wait: Introduce TASK_NOLOAD and TASK_IDLE") stopped the idle kthreads from contributing to the load average. However, the idle state time still contributes to the blocked state time instead of the sleep time. As a result, we cannot determine if a task is stopped due to some reasons or if it is idle by its own initiative. Distinguishing between these two states would make the system state clearer and provide us with an opportunity to use the 'D' state of a task as an indicator of latency issues. Originally-from: Curu Wong Signed-off-by: Alex Shi To: linux-kernel@vger.kernel.org To: Valentin Schneider To: Daniel Bristot de Oliveira To: Mel Gorman To: Ben Segall To: Steven Rostedt To: Dietmar Eggemann To: Vincent Guittot To: Juri Lelli To: Peter Zijlstra To: Ingo Molnar --- include/linux/sched.h | 6 ++++++ kernel/sched/deadline.c | 5 +++-- kernel/sched/fair.c | 5 +++-- kernel/sched/rt.c | 5 +++-- 4 files changed, 15 insertions(+), 6 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 292c31697248..002f80291837 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -140,6 +140,12 @@ struct user_event_mm; #define is_special_task_state(state) \ ((state) & (__TASK_STOPPED | __TASK_TRACED | TASK_PARKED | TASK_DEAD)) +/* blocked task is UNINTERRUPTIBLE but not NOLOAD */ +#define is_blocked_state(state) \ + ((state) & TASK_UNINTERRUPTIBLE && (!((state) & TASK_NOLOAD))) + +#define is_idle_state(state) (((state) & TASK_IDLE) == TASK_IDLE) + #ifdef CONFIG_DEBUG_ATOMIC_SLEEP # define debug_normal_state_change(state_value) \ do { \ diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index b28114478b82..99d46affc2aa 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1566,11 +1566,12 @@ update_stats_dequeue_dl(struct dl_rq *dl_rq, struct sched_dl_entity *dl_se, unsigned int state; state = READ_ONCE(p->__state); - if (state & TASK_INTERRUPTIBLE) + /* idle state still accounts into sleep */ + if (state & TASK_INTERRUPTIBLE || is_idle_state(state)) __schedstat_set(p->stats.sleep_start, rq_clock(rq_of_dl_rq(dl_rq))); - if (state & TASK_UNINTERRUPTIBLE) + if (is_blocked_state(state)) __schedstat_set(p->stats.block_start, rq_clock(rq_of_dl_rq(dl_rq))); } diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index d7a3c63a2171..69506253aadf 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1278,10 +1278,11 @@ update_stats_dequeue_fair(struct cfs_rq *cfs_rq, struct sched_entity *se, int fl /* XXX racy against TTWU */ state = READ_ONCE(tsk->__state); - if (state & TASK_INTERRUPTIBLE) + /* idle state still accounts into sleep */ + if (state & TASK_INTERRUPTIBLE || is_idle_state(state)) __schedstat_set(tsk->stats.sleep_start, rq_clock(rq_of(cfs_rq))); - if (state & TASK_UNINTERRUPTIBLE) + if (is_blocked_state(state)) __schedstat_set(tsk->stats.block_start, rq_clock(rq_of(cfs_rq))); } diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 6aaf0a3d6081..dd0e381689f8 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -1371,11 +1371,12 @@ update_stats_dequeue_rt(struct rt_rq *rt_rq, struct sched_rt_entity *rt_se, unsigned int state; state = READ_ONCE(p->__state); - if (state & TASK_INTERRUPTIBLE) + /* idle state still accounts into sleep */ + if (state & TASK_INTERRUPTIBLE || is_idle_state(state)) __schedstat_set(p->stats.sleep_start, rq_clock(rq_of_rt_rq(rt_rq))); - if (state & TASK_UNINTERRUPTIBLE) + if (is_blocked_state(state)) __schedstat_set(p->stats.block_start, rq_clock(rq_of_rt_rq(rt_rq))); } -- 2.43.0