From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793896310; b=EGaOixTYyDi4AhEXDsG3Ewr80PRtdKPYM6fV84tR0fza4TOOrOaHVzdTWJOPU45R5Tb0 1JMmSYZNXTW2XZqJxgOI9W6rez1zSoBifQq9I+N0+pFLiq1ngRDQoyzGQZzhnXw8tUzGm rE/THX3Swg+QGDeL0hUwaxHSAdb52qJapyNz8ewILcmxXFGTH3mUxtTvlE0STkVHOAm2B Sj3RlFj/K1mCerasRZ4WrvOkgT4KRsfPRPUrTuuHjT+kwWeZHOo3NHbvB+zHNhpEnfNut Wp9JMvPMbss+LCNZI9Fb3lwWg4l+UXCCakgtqzHI/0udxxMySXf4Fj7+A22f4mrvfnw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793896310; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=1YG6GqkB8WcinTnE6Efs8v7lhqd+S55sath7HlxpGDY=; b=Ljbe5T1H50aLmDjjDPyOvq63bvFWIgFR+IaXqGXSNgngiGPNGBs+ilYMzlqJWKWVSHcI SmFbEzRbgrPztVwRhQXahf6SwaJgUKPNeHL+p0MDD6OC43Wsk8+eeuE+tZz6C8kWI7NPz txZdEaeoSyr62RThwEZGTly74bh0ZMqUvokyP1ADgoc4qqAEPdSV+UQ5aXStBHvsZiVYm JEGAJm9d353AmxH07kKNjn1CqkTXaNprW/2WfvMoFZfOv1Rdoq2zVCMbhtWC4teqKCILA 2XR8CqYXuVvE+RLATCwkX5VfOVg3y/Fz1NwbAERnD0qT68P2Q+FdYxgOFGMz1+FAKsQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=QqOt2k9P; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4F0FB606D81C for ; Thu, 5 Nov 2026 16:31:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=QqOt2k9P Received: by smtp.kernel.org (Postfix) with ESMTPSA id BCB601F00919; Thu, 5 Nov 2026 16:31:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793896310; bh=1YG6GqkB8WcinTnE6Efs8v7lhqd+S55sath7HlxpGDY=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=QqOt2k9PQmF+h0ysOFrKZjWVDMKdg86OMBr8ssGaB6Cgrfw11+yf/ZhDOPrzsPZXD T2FiELiBmR0AIQMj7rVWkP6DbV1/DFC7R8xoICGjWaHQSI39ExMdqYLe3vmfO2aqO2 AtQ86iRzOivcDfRmrMe8rKSXU8PW/B8sXJlGFty+w71eLC6rggI7jXRSc24qUpQ9vj xnZ+qo/aqdUkX2qL2pNC3A/a6pd3xefVcVw+UuuiF6dgFCiZj81af2Z5bVXhByz5zY CCsGt7sFdf4PntJPKj2oICuLkvs5dsOn2xGXsiV6YDYmRtHVY70AaGhkwWKtENEKdF WiS3wiq8KKjEg== 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 17/47] ARM: vfp: Move CPUHP_AP_ARM_VFP_STARTING post stop_machine() Date: Thu, 5 Nov 2026 17:30:15 +0100 Message-ID: <20261105163045.38862-18-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-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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 only removes the local VFP state which is never accessed remotely. As such it 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 a9c5b0c1974b..4952a53e028b 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_XTENSA_STARTING); + enum cpuhp_state target = max((int)st->target, CPUHP_AP_ARM_VFP_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_XTENSA_STARTING); + WARN_ON(st->state != CPUHP_AP_ARM_VFP_STARTING); /* * Invoke the former CPU_DYING callbacks. DYING must not fail! */ -- 2.53.0