From nobody Thu Oct 2 12:02:40 2025 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (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 58ABB2EB5C4 for ; Thu, 18 Sep 2025 08:06:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.50.34 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758182818; cv=none; b=cZqW9V3xrBCAh7xRdg+38SYaNuP6sdOQVuG4/QzhJBmRp6dw2CnuXT2C8+0mjyBS3FOFHbMFXn3wqgR3YPlmqLJq/v9UrGKjo6nTXhkymeJu3mqR329GBXyNCB70w73eGR7tV5+wtSeudTX2fqHDuTXZM2ACNZpKSzeIYR2jOYk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758182818; c=relaxed/simple; bh=AeCzUiyAR/I0Tvdv/NWhP4mvqDzurjDvXBES4hJ84S4=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=po6xCeB7YOVRd7KllvGSFb5tCOTi8XTxYjCsxYJoQb1gp/HL/C8zbFCtwcCvkdeqk/TmOSvBa2QZXACnke6oTzuiEhytJLZyTc5eCDX2ZuWvHkGQ+u9Jln6C3U0hxdYWNO3xkmHfMNNutY0ebuRNAc3b0buiSYINjD5SNTnVqM8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=OS3odTvI; arc=none smtp.client-ip=90.155.50.34 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="OS3odTvI" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Type:MIME-Version:References: Subject:Cc:To:From:Date:Message-ID:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:In-Reply-To; bh=6CHdliF5fkO251zOWaCUfJIHKwCAxY5qzq5kGxF+XF4=; b=OS3odTvIBGetwlwqPSQkZb4nX2 pJWeuQ56oENcq8ZCLOQ1ultdGY0zTbBJjhHAIUOekIFruMF64BobXdpbpdIA9JfR4OF6mZA83mFv7 t7HPSbe97V97q9UGd9ERncykm/vS27CAYV98Odbo+9I0mMmKLAHW9QFHokq3nut6rEjJ7CntQIEHV z7sKlynQdNY1VXdZvGJfNRWlV0gB2LWsZ53Y0tTIQ7DxULBr6C8EmgSoby7l33jETZyYkf/CAwpdn gJpLWoUcif70ooWYGe/1jIF0u9lqgOm5Vrmu1cb8VPvgQV+suvTuAp/+zqZCZyZC69uTzCPH+r+HZ sMFMpjxg==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1uz9fC-0000000FbrQ-2B0q; Thu, 18 Sep 2025 08:06:46 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 0) id 23AF5302E5F; Thu, 18 Sep 2025 10:06:46 +0200 (CEST) Message-ID: <20250918080205.835307230@infradead.org> User-Agent: quilt/0.68 Date: Thu, 18 Sep 2025 09:52:23 +0200 From: Peter Zijlstra To: tglx@linutronix.de Cc: arnd@arndb.de, anna-maria@linutronix.de, frederic@kernel.org, peterz@infradead.org, luto@kernel.org, mingo@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, vschneid@redhat.com, linux-kernel@vger.kernel.org, oliver.sang@intel.com Subject: [PATCH 4/8] hrtimer: Optimize __hrtimer_start_range_ns() References: <20250918075219.091828500@infradead.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Much like hrtimer_reprogram(), skip programming is the cpu_base is running the hrtimer interrupt. Signed-off-by: Peter Zijlstra (Intel) --- kernel/time/hrtimer.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1261,6 +1261,14 @@ static int __hrtimer_start_range_ns(stru } =20 first =3D enqueue_hrtimer(timer, new_base, mode); + + /* + * If the hrtimer interrupt is running, then it will reevaluate the + * clock bases and reprogram the clock event device. + */ + if (new_base->cpu_base->in_hrtirq) + return 0; + if (!force_local) { /* * If the current CPU base is online, then the timer is