From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 71FBB34A3A5 for ; Sat, 4 Apr 2026 05:36:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775281010; cv=none; b=HlnNnkE6Q5UXYtTqALTIIwgfD1PDZlxZHT9PuG+fmgb2L/cjursWulFrGA8f6JrDgkRUfWAJyk9fCLPbMR1P9LnVoNU/MMKuj53uCQS90gJ5+7v/6Zt6itLhs6HCyODHTNGMsExmEPhNzh+6SHVc9GcMjhBro/epNUNEAEUrJS4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775281010; c=relaxed/simple; bh=XlW9p26G5sW8xpujfOCavtuqXZ864bkciDyBKiMbNik=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=ZcV0i//CnQGADXIZwC8GWJaL7IhwQyKeK0+GPpPbcwVDpYoIt0ZkiZuW7LTfiLiP2ao5E52LgLUO8NaoXVg04EaVadEdYUbGOBun8Ll1mLnteBeI4X9PqG2hWuqhPZVvh/TguiYvoQ+9PtkRrC/azjTVxJQiPFduO15P3Wd9H9I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jstultz.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=Pn+Mtty4; arc=none smtp.client-ip=209.85.214.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--jstultz.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Pn+Mtty4" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-2b249975139so60944885ad.0 for ; Fri, 03 Apr 2026 22:36:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1775281009; x=1775885809; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=aPxiEVgXKSmdKrjgrCQi/zOjLhPhgBmFhxWG4tzc/xQ=; b=Pn+Mtty4BdDSrbge7iV2aWoCZvYEGfiK4SPmZlI9DvgWwRcvPMEcGJ1nLGnXSxupRA M7IHt9sRV0kBPMQYN1oWvmI5LiapYc9Mgikwlkgl4L4r+QZx9CKz0Jh+mAXBrZCK4zXg w8cjBhTBOeimG7ZblDPhzF17dL+Mpql76wHHq8Axi9LFsywE2nMGLHuWPNe3fKlwq2BA 5QWH0HDAK6/9pC+QT7kzk+NJ1bPPp0RHXgo/VTnHXRjZznmKE4LkL4gtaBZjeF4JWPYp F1Jm1u2LKCr4YCzDTcd5Pnjyqb+Qm9Jwz4tZrCXapXcdHqvZn27wQTDerp0d1yLgl+TF lUuA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1775281009; x=1775885809; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=aPxiEVgXKSmdKrjgrCQi/zOjLhPhgBmFhxWG4tzc/xQ=; b=ljc5oAAJ2Whz4sA7J2FylXLHegccrYY25VtLSA8ggTk8DEq5tMFfmkeNYAAMrdjtdn uaSSHiLlcmhfj7hbftVcid55bNMhTSkYKP4yX8thS7+ynCQzrH5iGme4Xl+867SsF9b5 PMWcXmNieSwN5Ij4CFQ1hSkJ/HDljEzz2+b6TZN9ZWBS+W68rga7b6J0HBC0mocIIPyw ONeJ6n6QFsdKszcLbat64dbkjm5VJw8L3D0XR980PkSZCMl4jEdEHI/f01D0LDp5Xl3Q gLir6h2SnoHJxl0w2SDFKl0Fls0cl1AWnJXlMvuusdiPGEd6bDtxsuduEDf5M1ZVJRbi diXQ== X-Gm-Message-State: AOJu0YxlWJpt6jTT+vNKSoZdB0zNFXdiMffg+ER5cZ2Fdfrx6ARxAn/R sVbAL32Goy0uCDls/pSzNGOhjg6nYytHU+AXSB6MQj5SnNwMwVv+oorfuPqOgM11y5ofe5k+pZ2 Hpdc/yKGe/JVRG1UXsl7khmaus0XcwXDuH/ISavePujraWTrtVchAqgycekPGei/GVFYckv6QfG B62LZOkRU5ai+901kxOmLuM+97ifEWeDCPSi9Tw+M2ndSL5C7W X-Received: from pgcv14.prod.google.com ([2002:a05:6a02:530e:b0:c73:9264:56a5]) (user=jstultz job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a20:7f91:b0:398:71f2:59d8 with SMTP id adf61e73a8af0-39f2f1296b9mr5246612637.56.1775281008195; Fri, 03 Apr 2026 22:36:48 -0700 (PDT) Date: Sat, 4 Apr 2026 05:36:22 +0000 In-Reply-To: <20260404053632.1729280-1-jstultz@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260404053632.1729280-1-jstultz@google.com> X-Mailer: git-send-email 2.53.0.1213.gd9a14994de-goog Message-ID: <20260404053632.1729280-6-jstultz@google.com> Subject: [PATCH v27 05/10] sched: Rework block_task so it can be directly called From: John Stultz To: LKML Cc: John Stultz , Peter Zijlstra , Joel Fernandes , Qais Yousef , Ingo Molnar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Valentin Schneider , Steven Rostedt , Ben Segall , Zimuzo Ezeozue , Mel Gorman , Will Deacon , Waiman Long , Boqun Feng , "Paul E. McKenney" , Metin Kaya , Xuewen Yan , K Prateek Nayak , Thomas Gleixner , Daniel Lezcano , Suleiman Souhlal , kuyo chang , hupu , kernel-team@android.com Content-Type: text/plain; charset="UTF-8" Pull most of the logic out of try_to_block_task() and put it into block_task() directly, so that we can call block_task() and not have to worry about the failing cases in try_to_block_task() Suggested-by: Peter Zijlstra Signed-off-by: John Stultz --- Cc: Joel Fernandes Cc: Qais Yousef Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Juri Lelli Cc: Vincent Guittot Cc: Dietmar Eggemann Cc: Valentin Schneider Cc: Steven Rostedt Cc: Ben Segall Cc: Zimuzo Ezeozue Cc: Mel Gorman Cc: Will Deacon Cc: Waiman Long Cc: Boqun Feng Cc: "Paul E. McKenney" Cc: Metin Kaya Cc: Xuewen Yan Cc: K Prateek Nayak Cc: Thomas Gleixner Cc: Daniel Lezcano Cc: Suleiman Souhlal Cc: kuyo chang Cc: hupu Cc: kernel-team@android.com --- kernel/sched/core.c | 45 +++++++++++++++++++++++---------------------- 1 file changed, 23 insertions(+), 22 deletions(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 9c8a769a6d109..8f1b14a830851 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2160,8 +2160,29 @@ void deactivate_task(struct rq *rq, struct task_struct *p, int flags) dequeue_task(rq, p, flags); } -static void block_task(struct rq *rq, struct task_struct *p, int flags) +static void block_task(struct rq *rq, struct task_struct *p, unsigned long task_state) { + int flags = DEQUEUE_NOCLOCK; + + p->sched_contributes_to_load = + (task_state & TASK_UNINTERRUPTIBLE) && + !(task_state & TASK_NOLOAD) && + !(task_state & TASK_FROZEN); + + if (unlikely(is_special_task_state(task_state))) + flags |= DEQUEUE_SPECIAL; + + /* + * __schedule() ttwu() + * prev_state = prev->state; if (p->on_rq && ...) + * if (prev_state) goto out; + * p->on_rq = 0; smp_acquire__after_ctrl_dep(); + * p->state = TASK_WAKING + * + * Where __schedule() and ttwu() have matching control dependencies. + * + * After this, schedule() must not care about p->state any more. + */ if (dequeue_task(rq, p, DEQUEUE_SLEEP | flags)) __block_task(rq, p); } @@ -6517,7 +6538,6 @@ static bool try_to_block_task(struct rq *rq, struct task_struct *p, unsigned long *task_state_p, bool should_block) { unsigned long task_state = *task_state_p; - int flags = DEQUEUE_NOCLOCK; if (signal_pending_state(task_state, p)) { WRITE_ONCE(p->__state, TASK_RUNNING); @@ -6537,26 +6557,7 @@ static bool try_to_block_task(struct rq *rq, struct task_struct *p, if (!should_block) return false; - p->sched_contributes_to_load = - (task_state & TASK_UNINTERRUPTIBLE) && - !(task_state & TASK_NOLOAD) && - !(task_state & TASK_FROZEN); - - if (unlikely(is_special_task_state(task_state))) - flags |= DEQUEUE_SPECIAL; - - /* - * __schedule() ttwu() - * prev_state = prev->state; if (p->on_rq && ...) - * if (prev_state) goto out; - * p->on_rq = 0; smp_acquire__after_ctrl_dep(); - * p->state = TASK_WAKING - * - * Where __schedule() and ttwu() have matching control dependencies. - * - * After this, schedule() must not care about p->state any more. - */ - block_task(rq, p, flags); + block_task(rq, p, task_state); return true; } -- 2.53.0.1213.gd9a14994de-goog