From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9C73F606BF02 for ; Thu, 5 Nov 2026 16:32:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=u8+ZJuu5; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=Ky3Ts5sb DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Unsubscribe-Post: List-Owner; bh=pYSZDDkB9KE0B4etIEkyJve5o1Mggby0d5u0jTSHpFw=; b=u8+ZJuu5IPau0p xPM2eCPiajF6IMq3nue0Hoii07t3S0m1xSFxlwiagXIJ0MSpsuIAo+UwTIAopEADcjAHkvW1PgeDp FZtzfzNLDZyWrFyEhg9vyWLOYtRRvDWgFp6Zvw5KP6cqdFYdNi3UdGeCjYOsdwpUSGlMXZgpziHtq Hp6Id/zXL0kuZZDgaTnQrVh3/t7ZGAdMVVxIJvhfQ1JkblUrL7uukt7QoiJK+/hP0+nVM0GG/87O0 u9lHPusdfCXMO4km693THe9MS3AtwwD3G4YYThgvZLqUoY6RXJzlJEbmuC7rH6NbFR/n4z3Kt9Nxl 82t2ueXQUE0CJu7OAOfA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xP0Nz-00000009dBY-3zQD; Thu, 05 Nov 2026 16:32:23 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xP0Ne-00000009cy2-3Npk for linux-arm-kernel@lists.infradead.org; Thu, 05 Nov 2026 16:32:04 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 8EC7B43650; Thu, 5 Nov 2026 16:32:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4091E1F00919; Thu, 5 Nov 2026 16:32:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793896322; bh=pYSZDDkB9KE0B4etIEkyJve5o1Mggby0d5u0jTSHpFw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Ky3Ts5sbmUIVXA7k0qkLZif0mX72I2sI4IsgDNT1CsBFWPXJWfdFmcW0vRPbzpNZw DuPe9d2TuK7Z+ceAW4a8SYO0BelVpW6rDDsLUGaddVFX0AK6XUj3aOuR4YE02a7ujD UBxefPU+WwF0M11te7x72zHqMoe+cZt1mWQS7DEIVBEbV3V6eOd2+8DGFC3ROPGn5w uQO84Gqg3T0AowMax1bQwl3VP5hnh1HWvgjZ86Y2iLnzdCSdqb3jZVW2SNWc9dzIQD t0qVrPMgXNa7DAh14kIhoeC2N2cduO6kGa0hpNPSHOBkbQ/d21J5twcNYNVgkby+vR DVYK4GT+DseMA== From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Marco Crivellari , Peter Zijlstra , Phil Auld , Russell King , Thomas Gleixner , Waiman Long , linux-arm-kernel@lists.infradead.org, "Paul E. McKenney" Subject: [PATCH 21/47] ARM: l2c: Move CPUHP_AP_ARM_L2X0_STARTING post stop_machine() Date: Thu, 5 Nov 2026 17:30:19 +0100 Message-ID: <20261105163045.38862-22-frederic@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20261105163045.38862-1-frederic@kernel.org> References: <20261105163045.38862-1-frederic@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" X-Spam-Status: No, score=-18.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 Between CPUHP_TEARDOWN_CPU and CPUHP_AP_OFFLINE, stop_machine executes all the teardown callbacks while stopping all CPUs in the system. This doesn't mix-up well with running RT or isolated tasks. In order to transition smoothly from global stop_machine to finer grained synchronization between teardown callbacks and the other CPUs, a new stop machine post function has been introduced to be executed after the main one with IRQs still disabled while other CPUs can exit stop_machine(). The teardown callback here disables the L1/L2 cache prefetch and the write full line of zeros mode. These operations should only impact the outgoing CPU and can run concurrently with other CPUs. Move it to post stop_machine() accordingly. Signed-off-by: Frederic Weisbecker --- kernel/cpu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/cpu.c b/kernel/cpu.c index 2ad19f3f2563..498ff31b24cf 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -1275,7 +1275,7 @@ void clear_tasks_mm_cpumask(int cpu) static int take_cpu_down(void *_param) { struct cpuhp_cpu_state *st = this_cpu_ptr(&cpuhp_state); - enum cpuhp_state target = max((int)st->target, CPUHP_AP_PERF_RISCV_STARTING); + enum cpuhp_state target = max((int)st->target, CPUHP_AP_ARM_L2X0_STARTING); int err, cpu = smp_processor_id(); /* Ensure this CPU doesn't handle any more interrupts. */ @@ -1303,7 +1303,7 @@ static int take_cpu_down_post(void *_param) enum cpuhp_state target = max((int)st->target, CPUHP_AP_OFFLINE); int cpu = smp_processor_id(); - WARN_ON(st->state != CPUHP_AP_PERF_RISCV_STARTING); + WARN_ON(st->state != CPUHP_AP_ARM_L2X0_STARTING); /* * Invoke the former CPU_DYING callbacks. DYING must not fail! */ -- 2.53.0