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

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@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