From nobody Wed Oct 8 17:31:55 2025 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 E9AB6EED8 for ; Thu, 26 Jun 2025 11:51:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750938720; cv=none; b=LSh+RruXhc1Nk+qqCgtpD5Q7v7iXDZQNCz4mxZMh6aP8RRhrjTPkpcLgawSLgeCE+/VNkKPh16rPYXv9m1dvmTwWkeGm8U13WiOLD1rwCtuvPr/oc/pT5lyhiobrOuL+FFZJAIsGj8VRfLNLevSEdnMZyXfpo0IBZEFYnHZh0PU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750938720; c=relaxed/simple; bh=4t4ruMijuTTz0PHIOALP/OeEfG3Koa8TZ1n81NIJ54E=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ovXAYDOYGy+AGS7arPPQbJ5h2zxQ7xtQyNepemzYDo7r54sqsAbAFQ8cmdLNWxNXY+LNQlSE8kd+Qxfu39am0+wET4shTHwueOhCHcTsZOUSaKtEosmNZx3J0LMYk1v5ySxw6WXLv8Y4tvTYDO6OuLM4zrOIxQvHkC6Pk3TDy5k= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=J6f7jXYs; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="J6f7jXYs" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1750938717; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=NR3LGxHqzn0L/7QuZS0AvylpPMHJBKh+iHCZKjKiisU=; b=J6f7jXYsHiFI8jrzgPh8V0aZ/Km/jFGHGobZl7oz6FnaiOOQNyl90O+QUXN23kpwbrxw2z JnDcPwUaEOagVs5lgYOBvO8DWabsO1U/Q7+M3jFc5JPwLFrJ8Bo6Zpuf0QqlAkk/eK3W52 CFph6q9qdPvK8KojXUf4Y3rJe4hAG+U= Received: from mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-153-HnODCME-PLOCEVaKvOQhWw-1; Thu, 26 Jun 2025 07:51:56 -0400 X-MC-Unique: HnODCME-PLOCEVaKvOQhWw-1 X-Mimecast-MFC-AGG-ID: HnODCME-PLOCEVaKvOQhWw_1750938715 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 8A71919560B9; Thu, 26 Jun 2025 11:51:55 +0000 (UTC) Received: from gmonaco-thinkpadt14gen3.rmtit.com (unknown [10.45.226.174]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 1188930002C0; Thu, 26 Jun 2025 11:51:52 +0000 (UTC) From: Gabriele Monaco To: linux-kernel@vger.kernel.org, Anna-Maria Behnsen , Frederic Weisbecker , Thomas Gleixner , Waiman Long Cc: Gabriele Monaco Subject: [PATCH v7 2/7] timers: Add the available mask in timer migration Date: Thu, 26 Jun 2025 13:48:55 +0200 Message-ID: <20250626114900.106061-3-gmonaco@redhat.com> In-Reply-To: <20250626114900.106061-1-gmonaco@redhat.com> References: <20250626114900.106061-1-gmonaco@redhat.com> 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 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Content-Type: text/plain; charset="utf-8" Keep track of the CPUs available for timer migration in a cpumask. This prepares the ground to generalise the concept of unavailable CPUs. Signed-off-by: Gabriele Monaco --- kernel/time/timer_migration.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/kernel/time/timer_migration.c b/kernel/time/timer_migration.c index 2c2c8810b8137..2ec003c2bbbea 100644 --- a/kernel/time/timer_migration.c +++ b/kernel/time/timer_migration.c @@ -422,6 +422,9 @@ static unsigned int tmigr_crossnode_level __read_mostly; =20 static DEFINE_PER_CPU(struct tmigr_cpu, tmigr_cpu); =20 +/* CPUs available for timer migration */ +static cpumask_var_t tmigr_available_cpumask; + #define TMIGR_NONE 0xFF #define BIT_CNT 8 =20 @@ -1449,6 +1452,7 @@ static int tmigr_clear_cpu_available(unsigned int cpu) raw_spin_lock_irq(&tmc->lock); tmc->available =3D false; WRITE_ONCE(tmc->wakeup, KTIME_MAX); + cpumask_clear_cpu(cpu, tmigr_available_cpumask); =20 /* * CPU has to handle the local events on his own, when on the way to @@ -1459,7 +1463,7 @@ static int tmigr_clear_cpu_available(unsigned int cpu) raw_spin_unlock_irq(&tmc->lock); =20 if (firstexp !=3D KTIME_MAX) { - migrator =3D cpumask_any_but(cpu_online_mask, cpu); + migrator =3D cpumask_any(tmigr_available_cpumask); work_on_cpu(migrator, tmigr_trigger_active, NULL); } =20 @@ -1480,6 +1484,7 @@ static int tmigr_set_cpu_available(unsigned int cpu) if (!tmc->idle) __tmigr_cpu_activate(tmc); tmc->available =3D true; + cpumask_set_cpu(cpu, tmigr_available_cpumask); raw_spin_unlock_irq(&tmc->lock); return 0; } @@ -1801,6 +1806,11 @@ static int __init tmigr_init(void) if (ncpus =3D=3D 1) return 0; =20 + if (!zalloc_cpumask_var(&tmigr_available_cpumask, GFP_KERNEL)) { + ret =3D -ENOMEM; + goto err; + } + /* * Calculate the required hierarchy levels. Unfortunately there is no * reliable information available, unless all possible CPUs have been --=20 2.49.0