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 35547502779 for ; Mon, 19 Oct 2026 13:10:43 +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=1792415445; cv=none; b=lkA0c6wIfXDz02JoYl02p6XOd/hEhkTdzyi+sgIGUQkdj2xoIw5IzPL2OJnGHKCQr4FMekRSejRovPob5OF0vnC9e2WP5GPdUoqe4SMlBsvk38PuSB8cp5l98eODktGzpbG7vRAW2mHHJ+TMSbwrDkV0MN4KJyjCXBlL3vuMtQU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792415445; c=relaxed/simple; bh=rmnyhpCmegsBLxHCidiQLi7Y82sto3WFbEp7dsHHi9U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VYmZS19lAsSXL9xarvM1Az9ezGuAkd3W2A7zN2gr4/rjCKwQLHoObeGEHmTxk4ZLtM2pNbOWsS0mMG0yjhmA1cnNuunmxgOOWrmh/7VleEUww3Mbx2m40vxk7pdbykW2+suEws6QE67UQMyJ2HSy4u2SWODfmFOO8/KehFUm60A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=h9fuv/js; 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="h9fuv/js" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 35AB21F000C5; Mon, 19 Oct 2026 13:10:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792415443; bh=7ODb1dWP8rGg5ULadQFlCk+VziuG97Xhu5lJD6rqNDI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=h9fuv/jsyFVXpZxEXFm0TlW3vXsCqNJdPKRvhVzvT31yqqVnXN2fkYJYryxnvMZB3 Lyf7LALOY/m+B7wBf7Geu2C7oPRFt4q6sUeBU5c8YLlGnykoNre+WaitvqJvt2BzWD OcwK2MLWxIz9XxI8S795kPagAJY8gJg+K0++Lb908JEIWpJTRhM/3S1TAVVKLSguzx FmGL1og0wcieK6NT6XdixEGSg1C3wZ94IsFoJZ8YIrqOI9eOy09uiutVbkLSrr0riA bpSBeFtkNNJ0RA/A8brn+HnxYiXFn3NtxxAoWnV0dxJvBQlNMZbT3IRbppdbxFS2Cx IjCz/DbuipCOA== From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Albert Ou , Alexandre Ghiti , Daniel Lezcano , Marco Crivellari , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Phil Auld , Thomas Gleixner , Waiman Long , linux-riscv@lists.infradead.org Subject: [RFC PATCH 35/49] clocksource/drivers/timer-riscv: Move CPUHP_AP_RISCV_TIMER_STARTING post stop_machine() Date: Mon, 19 Oct 2026 15:08:42 +0200 Message-ID: <20261019130856.49711-36-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 performs timer and IRQ disablement, both of which 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 374e7599baae..c2f25b6f72a4 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_REALTEK_TIMER_STARTING); + enum cpuhp_state target = max((int)st->target, CPUHP_AP_RISCV_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_REALTEK_TIMER_STARTING); + WARN_ON(st->state != CPUHP_AP_RISCV_TIMER_STARTING); /* * Invoke the former CPU_DYING callbacks. DYING must not fail! */ -- 2.53.0