From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 12DE124EF6B; Mon, 24 Feb 2025 15:14:55 +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=1740410097; cv=none; b=I1Lk4eCcaxkkZE/kWLN7lBhyQGK08npfT+26uF8C8wlW2ov7I2I+hL7ZQ4NrAiaHFFuxksUk4cb39LNFB5WFbs5rqjuZFpdH4QYj+zrK6oFmjLbfLOZ7SLajbOGaAPmJlROjumvdeGGniiRu6e55TPD+DcOF4XC96L7sZLE0z50= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740410097; c=relaxed/simple; bh=h1NUjbsWtVI+rR0BWHzHHmfjMA+kj2h8OixpmVCAlv4=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=I+NB7U6PTXAi9tZmwXD+2OOhB3LWh0xoi3Tj81NJ2r/EpDXYRd/5bZxctMTkgS9FeW0M5GigmpXUr6yT9mFGMn/md2Gd8EFex2U6xqXRXk0VlBk9GbWMW6JoRqDqwDxPwfbPriS4x1zH+/xmnF8bafMQz5agT+Nej33hoxXDRhM= 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 1B87E26AC; Mon, 24 Feb 2025 07:15:12 -0800 (PST) Received: from e132581.cambridge.arm.com (e132581.arm.com [10.2.76.71]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id ABBE43F6A8; Mon, 24 Feb 2025 07:14:53 -0800 (PST) From: Leo Yan To: Suzuki K Poulose , Mike Leach , James Clark , Jonathan Corbet , Alexander Shishkin , Namhyung Kim , Arnaldo Carvalho de Melo , coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Leo Yan Subject: [PATCH v1 6/8] coresight: perf: Update buffer on AUX pause Date: Mon, 24 Feb 2025 15:14:21 +0000 Message-Id: <20250224151423.1630639-7-leo.yan@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250224151423.1630639-1-leo.yan@arm.com> References: <20250224151423.1630639-1-leo.yan@arm.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Due to sinks like ETR and ETB don't support interrupt handling, the hardware trace data might be lost for continuous running tasks. This commit takes advantage of the AUX pause for updating trace buffer to mitigate the trace data losing issue. Signed-off-by: Leo Yan --- .../hwtracing/coresight/coresight-etm-perf.c | 38 ++++++++++++++++++- 1 file changed, 36 insertions(+), 2 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index d759663a1f7d..667110429de9 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -594,14 +594,48 @@ static void etm_event_start(struct perf_event *event, int flags) return; } -static void etm_event_pause(struct coresight_device *csdev, +static void etm_event_pause(struct perf_event *event, + struct coresight_device *csdev, struct etm_ctxt *ctxt) { + int cpu = smp_processor_id(); + struct coresight_device *sink; + struct perf_output_handle *handle = &ctxt->handle; + struct list_head *path; + unsigned long size; + if (!ctxt->event_data) return; /* Stop tracer */ coresight_pause_source(csdev); + + /* Bail out if no need update buffer */ + if (!ctxt->event_data->update_buf_on_pause) + return; + + if (WARN_ON_ONCE(handle->event != event)) + return; + + path = etm_event_cpu_path(ctxt->event_data, cpu); + sink = coresight_get_sink(path); + if (WARN_ON_ONCE(!sink)) + return; + + if (!sink_ops(sink)->update_buffer) + return; + + size = sink_ops(sink)->update_buffer(sink, handle, + ctxt->event_data->snk_config); + if (READ_ONCE(handle->event)) { + if (!size) + return; + + perf_aux_output_end(handle, size); + perf_aux_output_begin(handle, event); + } else { + WARN_ON_ONCE(size); + } } static void etm_event_stop(struct perf_event *event, int mode) @@ -615,7 +649,7 @@ static void etm_event_stop(struct perf_event *event, int mode) struct list_head *path; if (mode & PERF_EF_PAUSE) - return etm_event_pause(csdev, ctxt); + return etm_event_pause(event, csdev, ctxt); /* * If we still have access to the event_data via handle, -- 2.34.1