From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 39F454FD29F; Mon, 19 Oct 2026 13:10:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792415412; cv=none; b=p+NDu7tpTJcA/ic4hRT+AeW6+PEQziMlwabwaM/3Or73+9SQFxiPhOzpxqsI0EUjmYkmM98ymqLxU0MUNgk8wrU0aMF5GZI89K1d3nLqvQ6ar0rGmFCHSJF5unqCkxnAlCZavfDhKXfY6gohCJOQ9CbpJhGcP27VBEYLKdhyOco= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792415412; c=relaxed/simple; bh=gOc2iflYEYLam0Q6VPVzut2riggPOtkaY7ftQIo1ArI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ba+LMYlVDKmY9fzSO3TazhSMaiBlfUgzAxLaS8t3AlbnptSCs3/MZEuJr6kIQuSusq6ihWheYTkOddHDaYiMx3wPJIpKxIOx28A/lBHYGIIO/QD93w+Nbcd9zCfbkHVJa8B3dRiMv2OSC1HKoGimtPV4vJAHA3Zo+lpRY4n3O9Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RQfP/Wu/; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="RQfP/Wu/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 38E211F000C6; Mon, 19 Oct 2026 13:10:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792415410; bh=r6PkF4bnp6I0pVDOC8OuHY00fV+VdeZIgzJShsLaxsQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=RQfP/Wu/5UbTHx27ISIBvQBqbCm+3a/H+6MqmbDpIiq140xxhhCuWJGpTASB78+4w kwNn9qtpFHJDEYXI1WuuznYeWHwi6qUJDuK+xuyjLiqf/T6AIkMP3bB7o+MRSm1+wK zswGvgjCtBlSLOaXL18WF3VB7zyutByrJF8bwxccXrT+hAE5/eJScRWeqH2V1nxScQ WDbpEd086FTp+MTPhRKSz/lFlanDpF+JrGn34z2W8CJY+2zc/ObfZ8Zu7kC5Aczm0k ei+/ENwXcP432E6HX02g2Vs5kOdTKyv225a5aFx/ffU5sWskf7qfJDROnF3wWnMsJ2 t4wr/36dYgeFA== From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Alim Akhtar , Daniel Lezcano , Krzysztof Kozlowski , Marco Crivellari , Peter Griffin , Peter Zijlstra , Phil Auld , Thomas Gleixner , Waiman Long , linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org Subject: [RFC PATCH 22/49] clocksource/drivers/exynos_mct: Move CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING post stop_machine() Date: Mon, 19 Oct 2026 15:08:29 +0200 Message-ID: <20261019130856.49711-23-frederic@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20261019130856.49711-1-frederic@kernel.org> References: <20261019130856.49711-1-frederic@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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 simply disables the IRQ and clears/ack the interrupt bit on the local device. All these operations 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 c08ef67e3499..27e6542fb6c4 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_ARM_L2X0_STARTING); + enum cpuhp_state target = max((int)st->target, CPUHP_AP_EXYNOS4_MCT_TIMER_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_ARM_L2X0_STARTING); + WARN_ON(st->state != CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING); /* * Invoke the former CPU_DYING callbacks. DYING must not fail! */ -- 2.53.0