[PATCH v4 2/2] coresight: Update comments for removing cs_etm_find_snapshot()

Suzuki K Poulose suzuki.poulose at arm.com
Tue Sep 14 02:27:26 PDT 2021


On 12/09/2021 13:57, Leo Yan wrote:
> Commit 2f01c200d440 ("perf cs-etm: Remove callback cs_etm_find_snapshot()")
> has removed the function cs_etm_find_snapshot() from the perf tool in the
> user space, now CoreSight trace directly uses the perf common function
> __auxtrace_mmap__read() to calcualte the head and size for AUX trace data
> in snapshot mode.
> 
> This patch updates the comments in drivers to make them generic and not
> stick to any specific function from perf tool.
> 
> Signed-off-by: Leo Yan <leo.yan at linaro.org>
> ---
>   drivers/hwtracing/coresight/coresight-etb10.c   | 5 ++---
>   drivers/hwtracing/coresight/coresight-tmc-etf.c | 5 ++---
>   drivers/hwtracing/coresight/coresight-tmc-etr.c | 5 ++---
>   3 files changed, 6 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
> index f775cbee12b8..efa39820acec 100644
> --- a/drivers/hwtracing/coresight/coresight-etb10.c
> +++ b/drivers/hwtracing/coresight/coresight-etb10.c
> @@ -557,9 +557,8 @@ static unsigned long etb_update_buffer(struct coresight_device *csdev,
>   
>   	/*
>   	 * In snapshot mode we simply increment the head by the number of byte
> -	 * that were written.  User space function  cs_etm_find_snapshot() will
> -	 * figure out how many bytes to get from the AUX buffer based on the
> -	 * position of the head.
> +	 * that were written.  User space will figure out how many bytes to get
> +	 * from the AUX buffer based on the position of the head.
>   	 */
>   	if (buf->snapshot)
>   		handle->head += to_read;
> diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
> index cd0fb7bfba68..b416b1951d3e 100644
> --- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
> +++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
> @@ -546,9 +546,8 @@ static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev,
>   
>   	/*
>   	 * In snapshot mode we simply increment the head by the number of byte
> -	 * that were written.  User space function  cs_etm_find_snapshot() will
> -	 * figure out how many bytes to get from the AUX buffer based on the
> -	 * position of the head.
> +	 * that were written.  User space will figure out how many bytes to get
> +	 * from the AUX buffer based on the position of the head.
>   	 */
>   	if (buf->snapshot)
>   		handle->head += to_read;
> diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
> index d23c7690f29a..ce14eb83925c 100644
> --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
> +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
> @@ -1573,9 +1573,8 @@ tmc_update_etr_buffer(struct coresight_device *csdev,
>   
>   	/*
>   	 * In snapshot mode we simply increment the head by the number of byte
> -	 * that were written.  User space function  cs_etm_find_snapshot() will
> -	 * figure out how many bytes to get from the AUX buffer based on the
> -	 * position of the head.
> +	 * that were written.  User space will figure out how many bytes to get
> +	 * from the AUX buffer based on the position of the head.
>   	 */
>   	if (etr_perf->snapshot)
>   		handle->head += size;
> 


Thanks for the revised patch, I have queued both the patches.

Kind regards
Suzuki




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