From nobody Sun Apr 19 15:04:59 2026 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 49FAA28D83C; Thu, 22 May 2025 15:05:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747926328; cv=none; b=Tf7FcVNFzkcW1eRXt8q66JRgC1qntKX9Wvld8Deuh5k5vnjbXRQLTxovs8wLmCV+h4mKRpeFF9aSGwGVGxJReYdKN2o8rVP/0TCBFpFy9+4EXIMCxu7n9l1NeMtJF89NYhYBj4beX1zdLFnatywXzn4m6KpBwIYUVZEVHAdVEgU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747926328; c=relaxed/simple; bh=QCwBzjkhTS0fWQNm/uc3ctFPsORSVaqbTt6L7wL56dQ=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=iFC2+iWK9gKChev4DIi2A+uJ60MX2WlB7Yg7csAsMngEosj8O/EsPEYzV+t1owDuWEGrND6C/wWwSAxyQNS7ZlZ1qHMb+iptonUzADO5KcMXAdd+j4LoZwFyR2n83EjX6Tayr3yKD2vhZWZh5ui33CtXtHtmBZC7ak+kl4hhCMM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1CCD31A2D; Thu, 22 May 2025 08:05:11 -0700 (PDT) Received: from e132581.cambridge.arm.com (e132581.arm.com [10.1.196.87]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 0B4D23F673; Thu, 22 May 2025 08:05:22 -0700 (PDT) From: Leo Yan To: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , "Liang, Kan" , Marco Elver , Sebastian Andrzej Siewior , James Clark , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Leo Yan Subject: [PATCH] perf/aux: Properly launch pending disable flow Date: Thu, 22 May 2025 16:05:10 +0100 Message-Id: <20250522150510.2942814-1-leo.yan@arm.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" If an AUX event overruns, the event core layer intends to disable the event by setting the 'pending_disable' flag. Unfortunately, the event is not actually disabled afterwards. Since commit ca6c21327c6a ("perf: Fix missing SIGTRAPs"), the 'pending_disable' flag was changed to a boolean toggles. However, the AUX event code was not updated accordingly. The flag ends up holding a CPU number. If this number is zero, the flag is taken as false and the IRQ work is never triggered. Later, with commit 2b84def990d3 ("perf: Split __perf_pending_irq() out of perf_pending_irq()"), a new IRQ work 'pending_disable_irq' was introduced to handle event disabling. The AUX event path was not updated to kick off the work queue. To fix this issue, when an AUX ring buffer overrun is detected, call perf_event_disable_inatomic() to initiate the pending disable flow. Fixes: ca6c21327c6a ("perf: Fix missing SIGTRAPs") Fixes: 2b84def990d3 ("perf: Split __perf_pending_irq() out of perf_pending_= irq()") Signed-off-by: Leo Yan Reviewed-by: James Clark Reviewed-by: Yeoreum Yun --- kernel/events/ring_buffer.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index d2aef87c7e9f..aa9a759e824f 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -441,7 +441,7 @@ void *perf_aux_output_begin(struct perf_output_handle *= handle, * store that will be enabled on successful return */ if (!handle->size) { /* A, matches D */ - event->pending_disable =3D smp_processor_id(); + perf_event_disable_inatomic(handle->event); perf_output_wakeup(handle); WRITE_ONCE(rb->aux_nest, 0); goto err_put; @@ -526,7 +526,7 @@ void perf_aux_output_end(struct perf_output_handle *han= dle, unsigned long size) =20 if (wakeup) { if (handle->aux_flags & PERF_AUX_FLAG_TRUNCATED) - handle->event->pending_disable =3D smp_processor_id(); + perf_event_disable_inatomic(handle->event); perf_output_wakeup(handle); } =20 --=20 2.34.1