From nobody Sun Feb 8 15:08:35 2026 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 05459329C6F; Thu, 15 Jan 2026 21:44:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768513460; cv=none; b=Bmci4oC041xKVhs7UuG837J5GoWtaEBrdnD2xbaM7H5/ZAE+BBIFwD2FC+sLrvEoundIvtd7gXcBEPAIb2uF9xexTG1ieUV3kD2GHNeY189KXOpq1yJBhj4N768Uc9VqZNBSbAY6YWO8YT4NxGj+8h3cqe+NNqEEL4Gp7qJg0Ck= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768513460; c=relaxed/simple; bh=wzoqXH7lRicNF5PPHcF4WwCCc2F3wZTBiHaMRO3rsUs=; h=Date:From:To:Subject:Cc:In-Reply-To:References:MIME-Version: Message-ID:Content-Type; b=HLK44gBjnYlJmpbuFMIkviNFEsFQoTfr29zDIK7t5IqQO20PbPga0SCz0nYcGtnEEBFOZh7uaPlYez43eM3U12SyMQSfOym/1DvMl/wkNM7a3UThdhd7Lx7eAU9PR+SpIjSrHtYKSu9H7IwRE4ailLMetKOrfms55abEY2zhD8w= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=DtOGFGFS; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=obzTbAgg; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="DtOGFGFS"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="obzTbAgg" Date: Thu, 15 Jan 2026 21:44:16 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1768513457; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=v9dOMfBbl6EaNvRydmj8w6afcccq5V6Mw6sjEVQe+xs=; b=DtOGFGFSy8IE7V1Jp95454qld2SKY3XGVm4ICGqI8W6TNGy1qSEovNKyB6axRaKdayVBtP faYUfZ8D8jJ9Pkr2/rtt8pj5D7Sf6/HKnVlWFbRRlscXO9F+zV+M+BMPVCJtVu1+zbEUO5 XniSancl7KzCNY0sG4YVojnk0tcq/WJjI7HPf9qaFAnH/lh5NIqvu2Uat9CBw3oVV8qrIW MDTQ3l5TpNdNu3j9a5Oa2POgjIX4otx9sH9S86MI2ClpPQOq7AErKCTHIJ/IQl5zjlrCTh gS80yBsysNpbzzEu4ZyYold4DNq0iEXyBBJ0CHEgk3qPpN7tI5NGzCv/GltsCg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1768513457; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=v9dOMfBbl6EaNvRydmj8w6afcccq5V6Mw6sjEVQe+xs=; b=obzTbAgg4+pYGVWvHV0jdKTmEnRPP4TFoD11nEhTOR2+5HccZ5ZPgxUJNHjWpa6PTuuYux SI1MciX9+Peq8rBw== From: "tip-bot2 for Shrikanth Hegde" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: sched/core] sched/fair: Change likelyhood of nohz.nr_cpus Cc: Shrikanth Hegde , "Peter Zijlstra (Intel)" , Vincent Guittot , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20260115073524.376643-3-sshegde@linux.ibm.com> References: <20260115073524.376643-3-sshegde@linux.ibm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <176851345658.510.10023012687723072941.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the sched/core branch of tip: Commit-ID: 94e70734b4d034b9df795bd1ad3452ea96e742ca Gitweb: https://git.kernel.org/tip/94e70734b4d034b9df795bd1ad3452ea9= 6e742ca Author: Shrikanth Hegde AuthorDate: Thu, 15 Jan 2026 13:05:23 +05:30 Committer: Peter Zijlstra CommitterDate: Thu, 15 Jan 2026 22:41:27 +01:00 sched/fair: Change likelyhood of nohz.nr_cpus These days most of the system have multi cores. The likelyhood of at least one or more CPUs in nohz (idle state) is higher. Give accurate hint to the branch predictor. Reviewed-and-tested-by: K Prateek Nayak Signed-off-by: Shrikanth Hegde Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Vincent Guittot Link: https://patch.msgid.link/20260115073524.376643-3-sshegde@linux.ibm.com --- kernel/sched/fair.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 9afe0c6..4ae06ce 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -12459,9 +12459,9 @@ static void nohz_balancer_kick(struct rq *rq) =20 /* * None are in tickless mode and hence no need for NOHZ idle load - * balancing: + * balancing */ - if (likely(!atomic_read(&nohz.nr_cpus))) + if (unlikely(!atomic_read(&nohz.nr_cpus))) return; =20 if (rq->nr_running >=3D 2) {