Re: [PATCH] perf: correct SNOOPX field offset

From: peterz@infradead.org
To: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>, Al Grant <al.grant@foss.arm.com>,
	Arnaldo Carvalho de Melo <acme@redhat.com>,
	Andi Kleen <ak@linux.intel.com>,
	linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] perf: correct SNOOPX field offset
Date: Tue, 1 Sep 2020 17:12:04 +0200	[thread overview]
Message-ID: <20200901151204.GE2674@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20200901150630.GB1424523@kernel.org>

On Tue, Sep 01, 2020 at 12:06:30PM -0300, Arnaldo Carvalho de Melo wrote:

> Also you mixed up tools/ with include/ things, the perf part of the
> kernel is maintained by Ingo, PeterZ.

Right, it helps if the right people are on Cc.

> Peter, the patch is the one below, I'll collect the
> tools/include/uapi/linux/perf_event.h bit as it fixes the tooling,
> please consider taking the kernel part.

Al, can you resend with the right people on Cc? Also see below.

> ---
> 
> From:   Al Grant <al.grant@foss.arm.com>
> Subject: [PATCH] perf: correct SNOOPX field offset
> Message-ID: <9974f2d0-bf7f-518e-d9f7-4520e5ff1bb0@foss.arm.com>
> Date:   Mon, 24 Aug 2020 10:28:34 +0100
> 
> perf_event.h has macros that define the field offsets in the
> data_src bitmask in perf records. The SNOOPX and REMOTE offsets
> were both 37. These are distinct fields, and the bitfield layout
> in perf_mem_data_src confirms that SNOOPX should be at offset 38.
> 

This needs a Fixes: tag.

> Signed-off-by: Al Grant <al.grant@arm.com>
> 
> ---
> 
>   include/uapi/linux/perf_event.h       | 2 +-
>   tools/include/uapi/linux/perf_event.h | 2 +-
>   2 files changed, 2 insertions(+), 2 deletions(-)
> 
> ---
> 
> diff --git a/include/uapi/linux/perf_event.h 
> b/include/uapi/linux/perf_event.h
> index 077e7ee69e3d..3e5dcdd48a49 100644
> --- a/include/uapi/linux/perf_event.h
> +++ b/include/uapi/linux/perf_event.h
> @@ -1196,7 +1196,7 @@ union perf_mem_data_src {
> 
>   #define PERF_MEM_SNOOPX_FWD    0x01 /* forward */
>   /* 1 free */
> -#define PERF_MEM_SNOOPX_SHIFT  37
> +#define PERF_MEM_SNOOPX_SHIFT  38
> 
>   /* locked instruction */
>   #define PERF_MEM_LOCK_NA       0x01 /* not available */
> diff --git a/tools/include/uapi/linux/perf_event.h 
> b/tools/include/uapi/linux/perf_event.h
> index 077e7ee69e3d..3e5dcdd48a49 100644
> --- a/tools/include/uapi/linux/perf_event.h
> +++ b/tools/include/uapi/linux/perf_event.h
> @@ -1196,7 +1196,7 @@ union perf_mem_data_src {
> 
>   #define PERF_MEM_SNOOPX_FWD    0x01 /* forward */
>   /* 1 free */
> -#define PERF_MEM_SNOOPX_SHIFT  37
> +#define PERF_MEM_SNOOPX_SHIFT  38
> 
>   /* locked instruction */
>   #define PERF_MEM_LOCK_NA       0x01 /* not available */