From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f200.google.com (mail-pf1-f200.google.com [209.85.210.200]) (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 B07FE3B0AD0 for ; Fri, 7 Aug 2026 03:52:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.200 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786074765; cv=none; b=hTVo9cVoyOK471S9TakpnfaSU0tk/L59Q3pL6SL6uHj52wHIIdXwEZGYvmF7P2XPG2XZbmKqxtIysKujJaq8i29aPEzjJP0RX85t39EqpquhaZ7GL6krCTVaj1tGkOwEp1yDuqLB5f1mOArH55NMWNqLv2uop1151JOKV0E9qjk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786074765; c=relaxed/simple; bh=ytutfxjM7Kr/Xh6NGVjWZUggzWWeKNv3va6vplznXTg=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=afOFk4371vP4T18gor4Hzy2F5MiyHud/Mxi7sJLAQ100oF6vcI3O45ANE4qQLiCBcQc85UnIiBRSagEKGcGWsd7BecwSa5qzZ95J/ltai/NTnjUY6kssysPL819/Vj0SV7QPHs2bvROd/uUSOGMZa88jGJPQQY6X5BYz+lCCzIQ= 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=cEQmUaHh; arc=none smtp.client-ip=209.85.210.200 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="cEQmUaHh" Received: by mail-pf1-f200.google.com with SMTP id d2e1a72fcca58-84865f326efso3498689b3a.0 for ; Thu, 06 Aug 2026 20:52:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1786074763; x=1786679563; darn=vger.kernel.org; h=content-type:cc:to:from:subject:message-id:references:mime-version :in-reply-to:date:from:to:cc:subject:date:message-id:reply-to :content-type; bh=xhfpKoaMDL+R4VkwqXx0RUTIjsiiOPWkf+aiH45sxeI=; b=cEQmUaHhtASaznLtGpzQReCIEHSPlAmLBsdqavJcnNg/y1848tqB9BqZ8i7wj437+I mAa8WQO5iFoy8AtvAGPvEV7feard82l0q018dNgtirPgrfhkdSdnNykmTe/Nuta6xB8Y KjJOWWR+FG7NZG6aem68AH021SWUo8zBuxPKNUhrkdfUrNrl7QXwg/CpZQlWyodJPFw5 2d8m3nPp3GYfAYLzBZ9ZaqyCPtT1tbevDbX2GTiqsVvhzW36C8dw88FBHbu4+4v9Ab7L pSJUeX9cO5o6pgnjbb/eQaEk3uv721c0+x0m3aWkJ7lhxBuPKZTlaxLz3h/82GJQ1OzG 5ENQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1786074763; x=1786679563; h=content-type: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:content-type; bh=xhfpKoaMDL+R4VkwqXx0RUTIjsiiOPWkf+aiH45sxeI=; b=qtald89cY8uR3L9D/Ri9UZz7wbOYir9vnKmh+rURV3KCqMMBrOkWm1VmRTBLF4Ze6p fPya/q2h+mxT4Gqc7Mpfz7SV06083O49+7cVIdIYd4NUG8cpqNpkfLtAYqgdWDaVz/Co fIao7gz+ZevR64ulcaajh2jNj55s/WEilb9TwJy2eHn2aQmpHHKm0wkRnNkIEE5AYXs/ JpQTI8yY6SQ7XXasxdNQdEniPQzwC9V8FOlvDszZRz/+v4OkPXOXV/hcbAdigHN9MW3z 10LY5Y4dCoQMHFoQ+9dU0hG5MjqZrjxtpk93XyD1xeJD96tZqOqAyVlUyADUyZRcalZA 7Teg== X-Gm-Message-State: AOJu0YzeSBbbEtPOsru4EHhnfAoVuS3vQHzkW4/UiLrlS8qCeFyXOCBl l/PdS2zHBKmVOhnYTHxckjePmILwvUED9WorkB/3Opn+KOuOWVXN1NajTSLxQE8G7SIBnHKDNep sSWSKYi6S6TkLRPxBHxtEN+IHFvL2c3/ljPzEnuwxuGpa3BKVNmSCl9xJY3rzg5/EFOJIXwTUkf IuZPeWN3pb9jZEIPE8tQQj1BrVho6ultnOHc/W5GAzs/CVa/Qo X-Received: from pfwp49.prod.google.com ([2002:a05:6a00:26f1:b0:84a:894f:23f2]) (user=jstultz job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:181e:b0:848:2ae4:d2ba with SMTP id d2e1a72fcca58-84f2e05e84emr21553543b3a.28.1786074762558; Thu, 06 Aug 2026 20:52:42 -0700 (PDT) Date: Fri, 7 Aug 2026 03:52:15 +0000 In-Reply-To: <20260807035232.1881495-1-jstultz@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260807035232.1881495-1-jstultz@google.com> X-Mailer: git-send-email 2.55.0.654.g21b8a5bc05-goog Message-ID: <20260807035232.1881495-10-jstultz@google.com> Subject: [RESEND][PATCH v31 9/9] sched: Distinguish proxy activations from wakeups From: John Stultz To: LKML Cc: Andrea Righi , John Stultz , Joel Fernandes , Qais Yousef , Ingo Molnar , Peter Zijlstra , 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" From: Andrea Righi Sleeping-owner handling reactivates blocked waiters with wakeup enqueue semantics so scheduling classes can restore their runnable accounting. Unlike a normal wakeup, the waiter remains blocked and is only made runnable to donate its scheduling context. Add ENQUEUE_PROXY to identify this activation and set it alongside ENQUEUE_WAKEUP. Consume the internal marker in sched_ext and suppress SCX_ENQ_WAKEUP before invoking BPF so the activation can be handled as a blocked proxy donor. Signed-off-by: Andrea Righi 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: Andrea Righi Cc: kuyo chang Cc: hupu Cc: kernel-team@android.com --- kernel/sched/core.c | 2 +- kernel/sched/ext/ext.c | 8 ++++++++ kernel/sched/sched.h | 2 ++ 3 files changed, 11 insertions(+), 1 deletion(-) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index d813a9c2f0c35..c54e9fedc9cd8 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3900,7 +3900,7 @@ static void activate_blocked_waiters(struct rq *target_rq, { struct list_head bal_head; unsigned long flags; - int en_flags = ENQUEUE_WAKEUP | ENQUEUE_NOCLOCK; + int en_flags = ENQUEUE_WAKEUP | ENQUEUE_NOCLOCK | ENQUEUE_PROXY; if (!sched_proxy_exec()) return; diff --git a/kernel/sched/ext/ext.c b/kernel/sched/ext/ext.c index e3fa7b2fac9df..834c8b6dae6c9 100644 --- a/kernel/sched/ext/ext.c +++ b/kernel/sched/ext/ext.c @@ -2021,6 +2021,14 @@ static void enqueue_task_scx(struct rq *rq, struct task_struct *p, int core_enq_ int sticky_cpu = p->scx.sticky_cpu; u64 enq_flags = core_enq_flags | rq->scx.extra_enq_flags; + /* + * Sleeping-owner activation uses wakeup semantics for the core + * scheduling classes, but the donor remains blocked. Expose it to BPF + * as a blocked-donor admission rather than a full wakeup. + */ + if (core_enq_flags & ENQUEUE_PROXY) + enq_flags &= ~(ENQUEUE_PROXY | SCX_ENQ_WAKEUP); + if (enq_flags & ENQUEUE_WAKEUP) rq->scx.flags |= SCX_RQ_IN_WAKEUP; diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 56d9c09c485e6..e38988574cfa2 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -2540,6 +2540,7 @@ extern const u32 sched_prio_to_wmult[40]; * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline) * ENQUEUE_MIGRATED - the task was migrated during wakeup * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called + * ENQUEUE_PROXY - activate a blocked donor behind a waking owner * * XXX SAVE/RESTORE in combination with CLASS doesn't really make sense, but * SCHED_DEADLINE seems to rely on this for now. @@ -2571,6 +2572,7 @@ extern const u32 sched_prio_to_wmult[40]; #define ENQUEUE_MIGRATED 0x00040000 #define ENQUEUE_INITIAL 0x00080000 #define ENQUEUE_RQ_SELECTED 0x00100000 +#define ENQUEUE_PROXY 0x00200000 #define RETRY_TASK ((void *)-1UL) -- 2.55.0.654.g21b8a5bc05-goog