Re: [PATCH -tip] perf_counter: Add Generalized Hardware FPU support for AMD

[Ingo Molnar <mingo@elte.hu>]

* Jaswinder Singh Rajput <jaswinder@kernel.org> wrote:

>  $./perf stat -e add -e multiply -e fpu-store -e fpu-empty -e fpu-busy -e x87 -e mmx-3dnow -e sse-sse2 -- ls -lR /usr/include/ > /dev/null
> 
>  Performance counter stats for 'ls -lR /usr/include/':
> 
>            7335  add                       (   2.00x scaled)
>            8012  multiply                  (   1.99x scaled)
>            5229  fpu-store                 (   2.00x scaled)
>       793097355  fpu-empty                 (   2.00x scaled)
>             182  fpu-busy                  (   2.00x scaled)
>               6  x87                       (   2.01x scaled)
>               4  mmx-3dnow                 (   2.00x scaled)
>            8933  sse-sse2                  (   2.00x scaled)
> 
>     0.393548820  seconds time elapsed
> 
>  $./perf stat -e add -e multiply -e fpu-store -e fpu-empty -e fpu-busy -e x87 -e mmx-3dnow -e sse-sse2 -- /usr/bin/rhythmbox ~jaswinder/Music/singhiskinng.mp3
> 
>  Performance counter stats for '/usr/bin/rhythmbox /home/jaswinder/Music/singhiskinng.mp3':
> 
>        19583739  add                       (   2.01x scaled)
>        20856051  multiply                  (   2.01x scaled)
>        18669503  fpu-store                 (   2.00x scaled)
>     25100224054  fpu-empty                 (   1.99x scaled)
>        12540131  fpu-busy                  (   1.99x scaled)
>          207228  x87                       (   1.99x scaled)
>         1768418  mmx-3dnow                 (   2.00x scaled)
>        42286702  sse-sse2                  (   2.01x scaled)
> 
>   302.698647617  seconds time elapsed
> 
>  $./perf stat -e add -e multiply -e fpu-store -e fpu-empty -e fpu-busy -e x87 -e mmx-3dnow -e sse-sse2 -- /usr/bin/vlc ~jaswinder/Videos/Linus_Torvalds_interview_with_Charlie_Rose_Part_1.flv
> 
>  Performance counter stats for '/usr/bin/vlc /home/jaswinder/Videos/Linus_Torvalds_interview_with_Charlie_Rose_Part_1.flv':
> 
>      6572682335  add                       (   2.00x scaled)
>     11131555181  multiply                  (   2.00x scaled)
>      1317520699  fpu-store                 (   2.00x scaled)
>      9089415134  fpu-empty                 (   1.99x scaled)
>      2902772713  fpu-busy                  (   2.00x scaled)
>           26047  x87                       (   2.00x scaled)
>     24850978532  mmx-3dnow                 (   2.00x scaled)
>       262276117  sse-sse2                  (   2.01x scaled)
> 
>    96.169312358  seconds time elapsed
> 
> Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
> ---
>  arch/x86/kernel/cpu/perf_counter.c |   34 ++++++++++++++++++++++++++++++
>  include/linux/perf_counter.h       |   17 +++++++++++++++
>  kernel/perf_counter.c              |    1 +
>  tools/perf/util/parse-events.c     |   40 ++++++++++++++++++++++++++++++++++++
>  4 files changed, 92 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/x86/kernel/cpu/perf_counter.c b/arch/x86/kernel/cpu/perf_counter.c
> index b83474b..4417edf 100644
> --- a/arch/x86/kernel/cpu/perf_counter.c
> +++ b/arch/x86/kernel/cpu/perf_counter.c
> @@ -372,6 +372,12 @@ static const u64 atom_hw_cache_event_ids
>   },
>  };
>  
> +/*
> + * Generalized hw fpu event table
> + */
> +
> +static u64 __read_mostly hw_fpu_event_ids[PERF_COUNT_HW_FPU_MAX];

ok, this looks genuinely useful, but there are some gaps. Where's 
the divides? Plus things like mmx-3dnow are AMD specific, sse-sse2 
is x86 specific. We definitely want this general table, but the 
events should be truly general.

Also, how would this look like on Intel, roughly?

	Ingo