Re: [PATCH 1/2] perf print-events: Fix "perf list" can not display the PMU prefix for some hybrid cache events

[Ian Rogers]

On Wed, Sep 21, 2022 at 6:47 PM <zhengjun.xing@xxxxxxxxxxxxxxx> wrote:
>
> From: Zhengjun Xing <zhengjun.xing@xxxxxxxxxxxxxxx>
>
> Some hybrid hardware cache events are only available on one CPU PMU. For
> example, 'L1-dcache-load-misses' is only available on cpu_core. We have
> supported in the perf list clearly reporting this info, the function works
> fine before but recently the argument "config" in API is_event_supported()
> is changed from "u64" to "unsigned int" which caused a regression, the
> "perf list" then can not display the PMU prefix for some hybrid cache
> events. For the hybrid systems, the PMU type ID is stored at config[63:32],
> define config to "unsigned int" will miss the PMU type ID information, then
> the regression happened, the config should be defined as "u64".
>
> Before:
>  # ./perf list |grep "Hardware cache event"
>   L1-dcache-load-misses                              [Hardware cache event]
>   L1-dcache-loads                                    [Hardware cache event]
>   L1-dcache-stores                                   [Hardware cache event]
>   L1-icache-load-misses                              [Hardware cache event]
>   L1-icache-loads                                    [Hardware cache event]
>   LLC-load-misses                                    [Hardware cache event]
>   LLC-loads                                          [Hardware cache event]
>   LLC-store-misses                                   [Hardware cache event]
>   LLC-stores                                         [Hardware cache event]
>   branch-load-misses                                 [Hardware cache event]
>   branch-loads                                       [Hardware cache event]
>   dTLB-load-misses                                   [Hardware cache event]
>   dTLB-loads                                         [Hardware cache event]
>   dTLB-store-misses                                  [Hardware cache event]
>   dTLB-stores                                        [Hardware cache event]
>   iTLB-load-misses                                   [Hardware cache event]
>   node-load-misses                                   [Hardware cache event]
>   node-loads                                         [Hardware cache event]
>
> After:
>  # ./perf list |grep "Hardware cache event"
>   L1-dcache-loads                                    [Hardware cache event]
>   L1-dcache-stores                                   [Hardware cache event]
>   L1-icache-load-misses                              [Hardware cache event]
>   LLC-load-misses                                    [Hardware cache event]
>   LLC-loads                                          [Hardware cache event]
>   LLC-store-misses                                   [Hardware cache event]
>   LLC-stores                                         [Hardware cache event]
>   branch-load-misses                                 [Hardware cache event]
>   branch-loads                                       [Hardware cache event]
>   cpu_atom/L1-icache-loads/                          [Hardware cache event]
>   cpu_core/L1-dcache-load-misses/                    [Hardware cache event]
>   cpu_core/node-load-misses/                         [Hardware cache event]
>   cpu_core/node-loads/                               [Hardware cache event]
>   dTLB-load-misses                                   [Hardware cache event]
>   dTLB-loads                                         [Hardware cache event]
>   dTLB-store-misses                                  [Hardware cache event]
>   dTLB-stores                                        [Hardware cache event]
>   iTLB-load-misses                                   [Hardware cache event]
>
> Fixes: 9b7c7728f4e4 ("perf parse-events: Break out tracepoint and printing")
> Signed-off-by: Zhengjun Xing <zhengjun.xing@xxxxxxxxxxxxxxx>
> Reviewed-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>

Acked-by: Ian Rogers <irogers@xxxxxxxxxx>

Sorry for this breakage, I suspect that a long review on the
refactoring CL meant that I missed the intervening fix. Can we add a
test on this? It would need to be hybrid specific and skip otherwise.

Thanks,
Ian

> ---
>  tools/perf/util/print-events.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/print-events.c b/tools/perf/util/print-events.c
> index ba1ab5134685..04050d4f6db8 100644
> --- a/tools/perf/util/print-events.c
> +++ b/tools/perf/util/print-events.c
> @@ -239,7 +239,7 @@ void print_sdt_events(const char *subsys_glob, const char *event_glob,
>         strlist__delete(sdtlist);
>  }
>
> -static bool is_event_supported(u8 type, unsigned int config)
> +static bool is_event_supported(u8 type, u64 config)
>  {
>         bool ret = true;
>         int open_return;
> --
> 2.25.1
>