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 10FA95012BE; Mon, 19 Oct 2026 13:10:33 +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=1792415434; cv=none; b=E714BPfmJ4FpUPQIbXqm81pj9rLV6vgwZVhL5guucHPrgDvGndk3CufmC5fNcLFMsm6FvykLUcUUXi11l/ATdBhY+6cERZTIp55QenyOb5AWkhsjHEjyU6KGtWwIxxAfYMoqK/I2/tHCHSTweo9nzncnuZc6NLWly5ZXtDsDAqw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792415434; c=relaxed/simple; bh=cOFMTZ9UD7et+hx6VFm+A94x8pn2pk+SotAZL4M7UEQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=cmcWcyq87tZBVxR7yrOj5pabEwts4GutLoMJSMA4r8FrNWcBJPNiQ5sH7eDnGHlUY/YtxixAN85LckOGTBKJ8YO40pvSFl30WaKDHigDPCg4A1iopO5GYXRk/6bi/tf2CC2HFVbuk8wK9hMDhLEwISG2VGQuCY4czU6kDoxttqg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DV+mFgFV; 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="DV+mFgFV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 647D81F000C6; Mon, 19 Oct 2026 13:10:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1792415433; bh=t7XlK6cfxGRTky4P49u0Q2RlmiycoMBbsrwhU1sBfXE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=DV+mFgFVpqVBbRQ7Ea0Peq6j4cChM/XOSB0oHoOVbivzB+aM1NQvvlFXoq9YXWNWb Yx+70n7Z5qSwtvGElYOouKrem3W99hpe69tG/Up13id5bNKYDWwAG30ooduyHVb1ly OsM9FjSf8jugdpKf/4oRFjvvyxvaOgyWlVnLOlNwlq3SDB95Xadd00jGNNWwrjuwnL pDigatwQ0OmwBZD0pslA27pG936E4Z8PUELJmdNilFF+O5x0DJkB08+pAJyWGmipbo m30P7lHK1jl5oiou67OGhj4Pbi+c4uorehU/v/45bmiCir1Xmw4oHhRPV8gqf8TJ22 86dgwPf8ildIA== From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= , Arnd Bergmann , Huacai Chen , Jiaxun Yang , Marco Crivellari , Peter Zijlstra , Phil Auld , Thomas Gleixner , WANG Xuerui , Waiman Long , loongarch@lists.linux.dev Subject: [RFC PATCH 31/49] LoongArch: Move CPUHP_AP_LOONGARCH_ARCH_TIMER_STARTING post stop_machine() Date: Mon, 19 Oct 2026 15:08:38 +0200 Message-ID: <20261019130856.49711-32-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-Type: text/plain; charset=UTF-8 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 clears the interrupt on the CSR, operation that 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 daad3b496854..664831c50f0b 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_ARMADA_TIMER_STARTING); + enum cpuhp_state target = max((int)st->target, CPUHP_AP_LOONGARCH_ARCH_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_ARMADA_TIMER_STARTING); + WARN_ON(st->state != CPUHP_AP_LOONGARCH_ARCH_TIMER_STARTING); /* * Invoke the former CPU_DYING callbacks. DYING must not fail! */ -- 2.53.0