[PATCH v1 3/7] perf cs-etm: Calculate per CPU metadata array size

Suzuki K Poulose suzuki.poulose at arm.com
Mon Jan 11 02:28:55 EST 2021


On 1/9/21 7:44 AM, Leo Yan wrote:
> The metadata array can be extended over time and the tool, if using the
> predefined macro (like CS_ETMV4_PRIV_MAX for ETMv4) as metadata array
> size to copy data, it can cause compatible issue within different
> versions of perf tool.
> 
> E.g. we recorded a data file with an old version tool, afterwards if
> use the new version perf tool to parse the file, since the metadata
> array has been extended and the macro CS_ETMV4_PRIV_MAX has been
> altered, if use it to parse the perf data with old format, this will
> lead to mismatch.
> 
> To maintain backward compatibility, this patch calculates per CPU
> metadata array size on the runtime, the calculation is based on the
> info stored in the data file so that it's reliable.
> 
> Signed-off-by: Leo Yan <leo.yan at linaro.org>

Looks good to me.

Acked-by: Suzuki K Poulose <suzuki.poulose at arm.com>




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