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=1793896381; b=5dDA3TT2+5vH0O+auOEIb5cmW/4pJhCWVBvM9KGBdBYQ4oSqhSDp0m/7ai3Rf1FZI6mL 1OO9bBUrVfEui6RpU8/dP19irP2b4AyviXtGJKcYy6PHSKytqBjJQK3FY8CKXSQ/vCuoz m4EXQciV72YwyKxqsrJERINLOecJehVt0zDZaHcEowBZlK3sk8U0cUGa8dPq2/uzMLVt0 oC/VNX8zi5nxdaOZ3wevA0lQBpetVA6GYDPLqzlRw4HG6rdEijkgbWPB+vHZ0yViwU7PJ DcJ5KUiODCELf34u4ZUb9k2Sez6wh2y9lGyep6KWMYHHL4sjzD8meh42HtbpDc/FQpg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793896381; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=mSfS/VpYRDfWYW/SpRNCqzvpn0MjIMyjO/C7eGCEl2w=; b=T+dAZVp8qoQZ/+hqXeaKreZ6wAp3eq+TAew7wTP9JuikF+Vbafl6Zs9+muMfFxYzSylM 1FOmOg4QHyoXW+zyr1lcMVQU1PfvRv7YCS41ojzSdIMjGfVhnw6JvRh0YeQt1BFRoVayQ qii7d4X/RGwGWrDdav0FftuXoOQs672ejW85g+0ir9Aki96yOhk/47ebkA1MtAMhLTYcr s7mLijNJ9e+GVX709OCFa8vOZ7b37PzMK78H/cnfBESM+eUyRgbFOY+/RMExReyxFNXFb je+4CNO6X3hgpzausAAhug5XlFdnjC/DI4t0lr6V27au3XwLChRdV9y5vv6YgP0qfCQ== 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=m4bPPOtp; 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 E683E60A2621 for ; Thu, 5 Nov 2026 16:33:00 +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=m4bPPOtp Received: by smtp.kernel.org (Postfix) with ESMTPSA id CD9A91F0093A; Thu, 5 Nov 2026 16:32:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793896380; bh=mSfS/VpYRDfWYW/SpRNCqzvpn0MjIMyjO/C7eGCEl2w=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=m4bPPOtp2zJAdqidlzL44ZUwcSIC9juhPx3x3FhmCg1hPbcRpBDRyG8EA8ChBVcWO GsoSUrxFillZ7jeC7oF7W0RfXNllBtB1MuSHw2SlQYI0Kvf8W0dJ0zEha/+Drqoxtg fhJdvj4anabtrYu5rm41hco7crYH/n+TmP3kadAh2tfiXndhPdfUvN2nhgC6rtzX3M RFIkJzGhqHYnbo1SPdM4e6XhZQvqy2BjX9U0MYLPx6HAJlS336XfAETo65ACSFDd3G d659qkBkuWREd8f+R6qc9yEhJBthbgi5iTc/LbPFu0A8GKMqXFY/Az9ETzL+OkcWoq 9K/2w5/xv0l1Q== From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Marco Crivellari , Peter Zijlstra , Phil Auld , Russell King , Stefano Stabellini , Thomas Gleixner , Waiman Long , linux-arm-kernel@lists.infradead.org, xen-devel@lists.xenproject.org, "Paul E. McKenney" Subject: [PATCH 41/47] ARM: xen: Move CPUHP_AP_ARM_XEN_STARTING post stop_machine() Date: Thu, 5 Nov 2026 17:30:39 +0100 Message-ID: <20261105163045.38862-42-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 simply performs IRQ disablement, 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 47b33c6759aa..5c84a39f6f06 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_DUMMY_TIMER_STARTING); + enum cpuhp_state target = max((int)st->target, CPUHP_AP_ARM_XEN_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_DUMMY_TIMER_STARTING); + WARN_ON(st->state != CPUHP_AP_ARM_XEN_STARTING); /* * Invoke the former CPU_DYING callbacks. DYING must not fail! */ -- 2.53.0