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 5953B206F3D for ; Thu, 13 Mar 2025 09:11:39 +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=1741857100; cv=none; b=JpRGoEaUwDEeXo9XFq7+oOBMQ5hN7WbgwWmQ9fD9rjxVweKdW2VjHTCpXz6zC8kbj9tRu0xFgeH/uBvq+SHkUOKTvPG7NRaFKIEmNTUbwrYfmEwEDMnfHnVyP9sOXx8mb7cb3nZrHp7IN+BhD5jwLmUSNV9kgmUMWqpnexEVsF0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741857100; c=relaxed/simple; bh=yIr7LZaswVuWNIDY5ihrSHOVg1KWgJh68j6K0nqoGho=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=mdH1bgtRFhgj1kKvAxRjxIq66Ip7Qeo9xIKLysgcqLa6+Jl7PFhdxU77bjXHN1VVpd79Vmem7Mfwqsw/tiN26bzQnAiAJsOiBSXee9VmtLAIiawsI0bbjkEIBoT9imnVdDCB8NT08ZBQUGwQFCNxcHTaeFzQN2laTQ2yfvP9zfw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RZNmRjsJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="RZNmRjsJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3318CC4CEDD; Thu, 13 Mar 2025 09:11:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741857099; bh=yIr7LZaswVuWNIDY5ihrSHOVg1KWgJh68j6K0nqoGho=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RZNmRjsJVKxtCLjrK1u0TbbanxObmx0MJCtzq3R21ePW2IiZZ8vsB4zz28ZCglGkX j6buZYTsWYsE+RwK2aTNEWqsoOkciTl2Cj/ty8F9rfgM0SQDGygXp598finxHmcLoO +APKhsjnrenlsfxOlx4Re1Nkc0gcj0/vk2e/Q0kBuvc0pyk0y7o6N4gX7e55CVdGYR NgItI1ffvlK3opiywGsx2KOioVx5iJHHcENscHQyopl9S/MU1fRpLlq98qC2n7xF2a mF1GcMbcAEJNT2lDEjSxFyaLxZkeWNNI57a1ZkGaKwfrqP/OVMUUCz2i0ahRUTC7KX zuZ6+BevDHUoA== From: Sasha Levin To: stable@vger.kernel.org Cc: Felix Moessbauer , Sasha Levin Subject: Re: [PATCH 6.1.y 1/1] hrtimer: Use and report correct timerslack values for realtime tasks Date: Thu, 13 Mar 2025 05:11:37 -0400 Message-Id: <20250312203334-b3cc22061d84f853@stable.kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250311140706.435615-1-felix.moessbauer@siemens.com> References: Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Sasha's backport helper bot ] Hi, ✅ All tests passed successfully. No issues detected. No action required from the submitter. The upstream commit SHA1 provided is correct: ed4fb6d7ef68111bb539283561953e5c6e9a6e38 Status in newer kernel trees: 6.13.y | Present (exact SHA1) 6.12.y | Present (exact SHA1) 6.6.y | Not found Note: The patch differs from the upstream commit: --- 1: ed4fb6d7ef681 ! 1: a4d3916d07d4c hrtimer: Use and report correct timerslack values for realtime tasks @@ Metadata ## Commit message ## hrtimer: Use and report correct timerslack values for realtime tasks + commit ed4fb6d7ef68111bb539283561953e5c6e9a6e38 upstream. + The timerslack_ns setting is used to specify how much the hardware timers should be delayed, to potentially dispatch multiple timers in a single interrupt. This is a performance optimization. Timers of @@ fs/select.c: u64 select_estimate_accuracy(struct timespec64 *tv) } - ## kernel/sched/syscalls.c ## -@@ kernel/sched/syscalls.c: static void __setscheduler_params(struct task_struct *p, + ## kernel/sched/core.c ## +@@ kernel/sched/core.c: static void __setscheduler_params(struct task_struct *p, else if (fair_policy(policy)) p->static_prio = NICE_TO_PRIO(attr->sched_nice); @@ kernel/time/hrtimer.c: long hrtimer_nanosleep(ktime_t rqtp, const enum hrtimer_m - u64 slack; - - slack = current->timer_slack_ns; -- if (rt_task(current)) +- if (dl_task(current) || rt_task(current)) - slack = 0; hrtimer_init_sleeper_on_stack(&t, clockid, mode); --- Results of testing on various branches: | Branch | Patch Apply | Build Test | |---------------------------|-------------|------------| | stable/linux-6.1.y | Success | Success |