From: Leo Yan <leo.yan@arm.com>
To: James Clark <james.clark@linaro.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>,
Mike Leach <mike.leach@linaro.org>,
Alexander Shishkin <alexander.shishkin@linux.intel.com>,
Jonathan Corbet <corbet@lwn.net>,
coresight@lists.linaro.org, linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org
Subject: Re: [PATCH v2 0/6] coresight: Add format attribute for setting the timestamp interval
Date: Tue, 30 Sep 2025 16:20:20 +0100 [thread overview]
Message-ID: <20250930152020.GL7985@e132581.arm.com> (raw)
In-Reply-To: <20250814-james-cs-syncfreq-v2-0-c76fcb87696d@linaro.org>
On Thu, Aug 14, 2025 at 11:49:51AM +0100, James Clark wrote:
[...]
> This is added as an event format attribute, rather than a Coresight
> config because it's something that the driver is already configuring
> automatically in Perf mode with any unused counter, so it's not possible
> to modify this with a config.
Tested on Juno-r2 for this series:
# /mnt/build/perf record -e cs_etm/timestamp=1,ts_level=15/ -- ls
# /mnt/build/perf script -D | grep I_TIMESTAMP | wc
1305 11745 83337
# /mnt/build/perf record -e cs_etm/timestamp=1,ts_level=0/ -- ls
# /mnt/build/perf script -D | grep I_TIMESTAMP | wc
120668 1086012 7705024
We can see a small counter (2 ^ 0 = 1) that records significant
timestamp packets.
Tested-by: Leo Yan <leo.yan@arm.com>
prev parent reply other threads:[~2025-09-30 15:20 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-08-14 10:49 [PATCH v2 0/6] coresight: Add format attribute for setting the timestamp interval James Clark
2025-08-14 10:49 ` [PATCH v2 1/6] coresight: Change syncfreq to be a u8 James Clark
2025-08-14 10:49 ` [PATCH v2 2/6] coresight: Fix holes in struct etmv4_config James Clark
2025-08-14 10:49 ` [PATCH v2 3/6] coresight: Repack struct etmv4_drvdata James Clark
2025-09-30 14:41 ` Leo Yan
2025-08-14 10:49 ` [PATCH v2 4/6] coresight: Refactor etm4_config_timestamp_event() James Clark
2025-09-30 14:56 ` Leo Yan
2025-08-14 10:49 ` [PATCH v2 5/6] coresight: Add format attribute for setting the timestamp interval James Clark
2025-09-30 15:14 ` Leo Yan
2025-10-01 12:40 ` James Clark
2025-10-01 13:28 ` Leo Yan
2025-10-01 13:39 ` Leo Yan
2025-10-01 13:44 ` James Clark
2025-10-01 13:55 ` Leo Yan
2025-08-14 10:49 ` [PATCH v2 6/6] coresight: docs: Document etm4x ts_interval James Clark
2025-09-30 15:20 ` Leo Yan [this message]
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