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

From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Leo Yan <leo.yan@linaro.org>
Cc: Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@redhat.com>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Jiri Olsa <jolsa@kernel.org>, Namhyung Kim <namhyung@kernel.org>,
	John Garry <john.garry@huawei.com>, Will Deacon <will@kernel.org>,
	James Clark <james.clark@arm.com>,
	Mike Leach <mike.leach@linaro.org>,
	Kajol Jain <kjain@linux.ibm.com>, Ali Saidi <alisaidi@amazon.com>,
	Adrian Hunter <adrian.hunter@intel.com>,
	"Gustavo A. R. Silva" <gustavoars@kernel.org>,
	Anshuman Khandual <anshuman.khandual@arm.com>,
	Ian Rogers <irogers@google.com>, Like Xu <likexu@tencent.com>,
	German Gomez <german.gomez@arm.com>,
	Timothy Hayes <timothy.hayes@arm.com>,
	linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH v6 01/15] perf tools: sync addition of PERF_MEM_SNOOPX_PEER
Date: Thu, 11 Aug 2022 18:55:48 -0300	[thread overview]
Message-ID: <YvV65OewRk9YJP5K@kernel.org> (raw)
In-Reply-To: <20220811062451.435810-2-leo.yan@linaro.org>

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

I'm adding a:

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

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