Re: [PATCH v6 01/15] perf tools: sync addition of PERF_MEM_SNOOPX_PEER

From: Arnaldo Carvalho de Melo
Date: Thu Aug 11 2022 - 17:56:13 EST


Em Thu, Aug 11, 2022 at 02:24:37PM +0800, Leo Yan escreveu:
> From: Ali Saidi <alisaidi@xxxxxxxxxx>
>
> 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@xxxxxxxxxx>
> Reviewed-by: Leo Yan <leo.yan@xxxxxxxxxx>

I'm adding a:

Signed-off-by: Leo Yan <leo.yan@xxxxxxxxxx>

To the patches you're sending that you are not the original author, as
per defined in:

Documentation/process/submitting-patches.rst

---
The Signed-off-by: tag indicates that the signer was involved in the
development of the patch, or that he/she was in the patch's delivery path.
---

If you disagree and want to retract the patch, please let me know, this
so far is speculative and is only on my local branch for testing.

- Arnaldo

> ---
> 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 4653834f078f..e2b77fbca91e 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 */
> --
> 2.34.1

--

- Arnaldo