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 40000361657 for ; Wed, 22 Apr 2026 23:07:13 +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=1776899237; cv=none; b=WTcHdK4v4NTyH0g9eURp2bsSQ2eFcYTpWXAPpkvo23Dv24UGvJ6Oa79tpA/Nzo6fOtO/KUDXrliI5KfvqySzj+p5WkBwVNS/KXPJx72Som8mbdMIxFFJqSoQwwMUc2nvFPtnF8Z5KIzBcNPEaLO/oEYtUPHohl4DG1G55N8/EcU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776899237; c=relaxed/simple; bh=cRCb/LO+Fvqrp+IZrGguXi182Zak1qasNs6VIFWWQ78=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=qL7L+t8lhci2+qM28yUhyav7U6HnlgdcVIXy2d+TW0idwSN8f5reCsgcwxy0n8M7Jlq/k1frN0Rcit5Y4HlSJssD23gOMvtn7SYa6UVFfmrN7p2uyZvoB2ry15eY5IjLBtCDV2DF6l3nddvYnAEuyR2Jfm4dXjiJxcO8ycVj4QY= 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=WmbwIJhG; 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="WmbwIJhG" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-2aad5fec175so84531075ad.2 for ; Wed, 22 Apr 2026 16:07:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1776899232; x=1777504032; 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=XX06oNYxOK+/mKT5tcRc7TAoC7ph1g70pIJ9OefEGrI=; b=WmbwIJhGbErqFipvqkL1imhIC1RFLYphQ3k1eZ62FQL234SI5n6qJLDgshG5hOooc0 KfHBRYJyVOQXS259XyGE6V/q9TGzN7a53slonkKFm/LDx6yrrRvzjcOMxVk9y9QZmjcU rFnFfaj5iYQb1rLjU/Kwjw/r/R+mIphT5fcL1Hi2TJoOVUe29aWDUH0jYNKHhstTO9R0 AJNmexnWTDgA6nITHfz4ajMIkS+Lg+D96ACBAmd9LPGt9YFUUivUvTK5p4rZW7Xl7rVS ZTQ5i9EmHzWEdB9z1oTGaVv6NAlehKodq7JxaeYpRTqVeoPIqs4JgVv6ybr0ioW5QnQ6 dpWw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1776899232; x=1777504032; 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=XX06oNYxOK+/mKT5tcRc7TAoC7ph1g70pIJ9OefEGrI=; b=qF+XXOPyfaZACX3Q2gD6DCAFBRmnfig7C8I+ngZ2+c138qtXwwJluNo0PIaEMxRip7 Ccj2QEjcahnOpBgUbIYJGAa2tzMYQ8xxxOiugCWPZslfFeZ+3sUteMwoo7CFbNYq3lqQ uFF/7Vmd/WIlFat7+xZYwJHFXCyflB0IMEaoMeglsNwqp3G8OcTiEdRe+0izRBQl+X1g +nYGCyADlYJQ3J+Otqys8m6zI517izgpEb5XoBcS6mQJU6OECAI7w8Lt6MnP/DINErHd OrUwiMu231qEwvoH7uUVowsfXkJg1ohKC7xXsuN3wLvL25TuYWGTIwTTXxLwXc3KCyst Pbeg== X-Gm-Message-State: AOJu0Yx+1Q/PCwAJ4EVOO0D6I1KmTvS9mazd3r2jH2LhDaZ65JPEMcsq 242jsZ7yWztK+bzg98NnPGyHhSt/XvkR1U2Zt06KXaHa23kQuNp+V6nPw9DMcr+bShk0PoL2w79 zimws3CIDFuQGl/LfN4p8DOBTITg3rzg++ATwXMprgPd7xAWULRPeqJ4djxkn62Bh2swrjKIFYP sFzFutFweFVovmHC48y6ikp1VY4empwzXQUXegsm1DZr0jkgsA X-Received: from plvx5.prod.google.com ([2002:a17:902:9a45:b0:2b2:a704:94d8]) (user=jstultz job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:32c9:b0:2b0:5923:5194 with SMTP id d9443c01a7336-2b5f9fa70e1mr252694595ad.27.1776899232191; Wed, 22 Apr 2026 16:07:12 -0700 (PDT) Date: Wed, 22 Apr 2026 23:06:45 +0000 In-Reply-To: <20260422230659.903191-1-jstultz@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260422230659.903191-1-jstultz@google.com> X-Mailer: git-send-email 2.54.0.rc2.533.g4f5dca5207-goog Message-ID: <20260422230659.903191-5-jstultz@google.com> Subject: [PATCH v28 4/8] 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 , 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: 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 3ac6dd4d3c587..942af3b34ffe0 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2223,8 +2223,29 @@ 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); } @@ -6581,7 +6602,6 @@ 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); @@ -6601,26 +6621,7 @@ 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; } -- 2.54.0.rc2.533.g4f5dca5207-goog