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

[Xing Zhengjun]

On 9/22/2022 11:12 AM, Ian Rogers wrote:
> 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. I will add a test case for hybrid-specific later.
> 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

--
Zhengjun Xing