[PATCH v8 2/5] perf tools: sync addition of PERF_MEM_SNOOPX_PEER

kajoljain kjain at linux.ibm.com
Tue May 10 22:42:30 PDT 2022



On 5/5/22 00:18, Ali Saidi wrote:
> Add a flag to the perf mem data struct to signal that a request caused a
> cache-to-cache transfer of a line from a peer of the requestor and
> wasn't sourced from a lower cache level.  The line being moved from one
> peer cache to another has latency and performance implications. On Arm64
> Neoverse systems the data source can indicate a cache-to-cache transfer
> but not if the line is dirty or clean, so instead of overloading HITM
> define a new flag that indicates this type of transfer.
> 
> Signed-off-by: Ali Saidi <alisaidi at amazon.com>
> Reviewed-by: Leo Yan <leo.yan at linaro.org>
> ---
>  tools/include/uapi/linux/perf_event.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/include/uapi/linux/perf_event.h b/tools/include/uapi/linux/perf_event.h
> index d37629dbad72..7b88bfd097dc 100644
> --- a/tools/include/uapi/linux/perf_event.h
> +++ b/tools/include/uapi/linux/perf_event.h
> @@ -1310,7 +1310,7 @@ union perf_mem_data_src {
>  #define PERF_MEM_SNOOP_SHIFT	19
>  
>  #define PERF_MEM_SNOOPX_FWD	0x01 /* forward */
> -/* 1 free */
> +#define PERF_MEM_SNOOPX_PEER	0x02 /* xfer from peer */
>  #define PERF_MEM_SNOOPX_SHIFT  38
>  
>  /* locked instruction */
Patch looks good to me.

Reviewed-By: Kajol Jain<kjain at linux.ibm.com>

Thanks,
Kajol Jain



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