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 0018B217F3D; Mon, 18 Aug 2025 13:00:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755522033; cv=none; b=Q3dvi4fRY9rnKiFJJSm0vIvXjr1FQQh9JnPpueYcgZ531an9CeF+h9jFzYkm/W42nvsbApmSllsrjOcjSByfr6G5VASV/rAgBUMUfmHYKDtRcM0R1/cPeKhJHwAcQk+1qM3AT+f9Xo5gZ13rPhaYgoN/466Z77aHFQnKP6TsC00= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755522033; c=relaxed/simple; bh=zwsT0Q341VQEVB3oeJ/X6lNoElUrixqk058lLjgWUEE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=n5T+ktNxCft3Doz+iQLdqtuE5IwEoLN1Y7SsmNgXvpY4lBgMJAuV2vSamx5L4Ktvw8Ok3RjvB58I/KN+RWRymPQrNghdTBtSmmL4/6cfbM6raVxhISdVfYJX+PEjPOWpmqOkd8F4cXrT2FhQNPbM2kTIlM9zyQNf1NPBa/Ufqz0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=z0yHuboz; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="z0yHuboz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 638A8C4CEEB; Mon, 18 Aug 2025 13:00:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1755522032; bh=zwsT0Q341VQEVB3oeJ/X6lNoElUrixqk058lLjgWUEE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=z0yHubozZkEuJQcWt77k5MthMZkiCu4rpe/SvmmyFKXQU07wEHjr1mwVeNKoUDklk R3bFlmYFeAULhek9Iw44N+uPEM+h1cW2VrParwtrmHvj9uCfTpMa0vUDIbM94O1Gj2 dubVykaZhxJFsRV5OxsELACqENj/E8Z9NP/KOko8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Marcel Ziswiler , Juri Lelli , "Peter Zijlstra (Intel)" , Sasha Levin Subject: [PATCH 6.12 195/444] sched/deadline: Fix accounting after global limits change Date: Mon, 18 Aug 2025 14:43:41 +0200 Message-ID: <20250818124456.178304502@linuxfoundation.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250818124448.879659024@linuxfoundation.org> References: <20250818124448.879659024@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Juri Lelli [ Upstream commit 440989c10f4e32620e9e2717ca52c3ed7ae11048 ] A global limits change (sched_rt_handler() logic) currently leaves stale and/or incorrect values in variables related to accounting (e.g. extra_bw). Properly clean up per runqueue variables before implementing the change and rebuild scheduling domains (so that accounting is also properly restored) after such a change is complete. Reported-by: Marcel Ziswiler Signed-off-by: Juri Lelli Signed-off-by: Peter Zijlstra (Intel) Tested-by: Marcel Ziswiler # nuc & rock5b Link: https://lore.kernel.org/r/20250627115118.438797-4-juri.lelli@redhat.com Signed-off-by: Sasha Levin --- kernel/sched/deadline.c | 4 +++- kernel/sched/rt.c | 6 ++++++ 2 files changed, 9 insertions(+), 1 deletion(-) diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index 0a47e5155897..53e3670fbb1e 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -3227,6 +3227,9 @@ void sched_dl_do_global(void) if (global_rt_runtime() != RUNTIME_INF) new_bw = to_ratio(global_rt_period(), global_rt_runtime()); + for_each_possible_cpu(cpu) + init_dl_rq_bw_ratio(&cpu_rq(cpu)->dl); + for_each_possible_cpu(cpu) { rcu_read_lock_sched(); @@ -3242,7 +3245,6 @@ void sched_dl_do_global(void) raw_spin_unlock_irqrestore(&dl_b->lock, flags); rcu_read_unlock_sched(); - init_dl_rq_bw_ratio(&cpu_rq(cpu)->dl); } } diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 172c588de542..6ad6717084ed 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2951,6 +2951,12 @@ static int sched_rt_handler(const struct ctl_table *table, int write, void *buff } mutex_unlock(&mutex); + /* + * After changing maximum available bandwidth for DEADLINE, we need to + * recompute per root domain and per cpus variables accordingly. + */ + rebuild_sched_domains(); + return ret; } -- 2.39.5