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Message-ID: <2560dc81-7ff9-f907-9041-b309a8ef5509@linux.intel.com>
Date:   Thu, 16 Jun 2022 10:31:43 -0400
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Subject: Re: [PATCH] perf record: Support "--cputype" option for hybrid events
Content-Language: en-US
To:     Xing Zhengjun <zhengjun.xing@linux.intel.com>,
        Ian Rogers <irogers@google.com>
Cc:     acme@kernel.org, peterz@infradead.org, mingo@redhat.com,
        alexander.shishkin@intel.com, jolsa@kernel.org,
        namhyung@kernel.org, linux-kernel@vger.kernel.org,
        linux-perf-users@vger.kernel.org, ak@linux.intel.com
References: <20220615150823.2230349-1-zhengjun.xing@linux.intel.com>
 <CAP-5=fVnD=jiSav=UAV9E_mc8XtcHad107ww8JSeiJ2y4ucxDw@mail.gmail.com>
 <bc4d4c51-27ee-d8ef-a190-e5c7e587447b@linux.intel.com>
From:   "Liang, Kan" <kan.liang@linux.intel.com>
In-Reply-To: <bc4d4c51-27ee-d8ef-a190-e5c7e587447b@linux.intel.com>
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On 6/16/2022 4:31 AM, Xing Zhengjun wrote:
> Hi Ian,
> 
> On 6/15/2022 11:16 PM, Ian Rogers wrote:
>> On Wed, Jun 15, 2022 at 8:07 AM <zhengjun.xing@linux.intel.com> wrote:
>>>
>>> From: Zhengjun Xing <zhengjun.xing@linux.intel.com>
>>>
>>> perf stat already has the "--cputype" option to enable events only on 
>>> the
>>> specified PMU for the hybrid platform, this commit extends the 
>>> "--cputype"
>>> support to perf record.
>>>
>>> Without "--cputype", it reports events for both cpu_core and cpu_atom.
>>>
>>>   # ./perf record  -e cycles -a sleep 1 | ./perf report
>>>
>>>   # To display the perf.data header info, please use 
>>> --header/--header-only options.
>>>   #
>>>   [ perf record: Woken up 1 times to write data ]
>>>   [ perf record: Captured and wrote 0.000 MB (null) ]
>>>   #
>>>   # Total Lost Samples: 0
>>>   #
>>>   # Samples: 335  of event 'cpu_core/cycles/'
>>>   # Event count (approx.): 35855267
>>>   #
>>>   # Overhead  Command          Shared Object      Symbol
>>>   # ........  ...............  .................  
>>> .........................................
>>>   #
>>>       10.31%  swapper          [kernel.kallsyms]  [k] poll_idle
>>>        9.42%  swapper          [kernel.kallsyms]  [k] menu_select
>>>        ...    ...               ...               ... ...
>>>
>>>   # Samples: 61  of event 'cpu_atom/cycles/'
>>>   # Event count (approx.): 16453825
>>>   #
>>>   # Overhead  Command        Shared Object      Symbol
>>>   # ........  .............  .................  
>>> ......................................
>>>   #
>>>       26.36%  snapd          [unknown]          [.] 0x0000563cc6d03841
>>>        7.43%  migration/13   [kernel.kallsyms]  [k] 
>>> update_sd_lb_stats.constprop.0
>>>        ...    ...            ...                ... ...
>>>
>>> With "--cputype", it reports events only for the specified PMU.
>>>
>>>   # ./perf record --cputype core  -e cycles -a sleep 1 | ./perf report
>>>
>>>   # To display the perf.data header info, please use 
>>> --header/--header-only options.
>>>   #
>>>   [ perf record: Woken up 1 times to write data ]
>>>   [ perf record: Captured and wrote 0.000 MB (null) ]
>>>   #
>>>   # Total Lost Samples: 0
>>>   #
>>>   # Samples: 221  of event 'cpu_core/cycles/'
>>>   # Event count (approx.): 27121818
>>>   #
>>>   # Overhead  Command          Shared Object      Symbol
>>>   # ........  ...............  .................  
>>> .........................................
>>>   #
>>>       11.24%  swapper          [kernel.kallsyms]  [k] e1000_irq_enable
>>>        7.77%  swapper          [kernel.kallsyms]  [k] 
>>> mwait_idle_with_hints.constprop.0
>>>        ...    ...              ...                ... ...
>>
>> This is already possible by having the PMU name as part of the event,
>> cpu_atom/cycles/ or cpu_core/cycles/. I don't know why we're adding
>> "hybrid" all over the code base, I wish it would stop. You are asking
>> for an option here for an implied PMU for events that don't specify a
>> PMU. The option should be called --pmutype and consider all PMUs. 

The --pmutype should be redundant because other PMUs have to specify the 
PMU name with the event. Only the CPU type of PMUs have events which 
doesn't have a PMU name prefix, e.g., cycles, instructions.
So the "--cputype" was introduced for perf stat to avoid the annoying 
pmu prefix for the CPU type of PMU.

This patch just extends the "--cputype" to perf record to address the 
request from the community. It reuses the existing function.

>> We
>> should remove the "hybrid" PMU list and make all of the "hybrid" code
>> generic.

We already start to rework on the "hybrid" code.

We recently rework the perf stat default
https://lore.kernel.org/lkml/20220610025449.2089232-1-zhengjun.xing@linux.intel.com/

With the help of Ravi, we clean up the hybrid CPU in the perf header.
https://lore.kernel.org/all/20220604044519.594-6-ravi.bangoria@amd.com/

I think Zhengjun will work on the perf record default cleanup shortly.

Then I guess we can further clean up the "--cputype", e.g., removing 
hybrid_pmu_name from evlist... as next step.

Thanks,
Kan
>>
> 
> I can change the option name from "cputype" to "pmutype". We have 
> planned to clean up the hybrid code, and try to reduce the code with "if 
> perf_pmu__has_hybrid()", this will be done step by step, from this 
> patch, we have begun to do some clean-up, move the hybrid API from the 
> common file to the hybrid-specific files. For the clean-up, Do you have 
> any ideas? Thanks.
> 
>> Thanks,
>> Ian
>>
>>> Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
>>> Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
>>> ---
>>>   tools/perf/Documentation/perf-record.txt |  4 ++++
>>>   tools/perf/builtin-record.c              |  3 +++
>>>   tools/perf/builtin-stat.c                | 20 --------------------
>>>   tools/perf/util/pmu-hybrid.c             | 19 +++++++++++++++++++
>>>   tools/perf/util/pmu-hybrid.h             |  2 ++
>>>   5 files changed, 28 insertions(+), 20 deletions(-)
>>>
>>> diff --git a/tools/perf/Documentation/perf-record.txt 
>>> b/tools/perf/Documentation/perf-record.txt
>>> index cf8ad50f3de1..ba8d680da1ac 100644
>>> --- a/tools/perf/Documentation/perf-record.txt
>>> +++ b/tools/perf/Documentation/perf-record.txt
>>> @@ -402,6 +402,10 @@ Enable weightened sampling. An additional weight 
>>> is recorded per sample and can
>>>   displayed with the weight and local_weight sort keys.  This 
>>> currently works for TSX
>>>   abort events and some memory events in precise mode on modern Intel 
>>> CPUs.
>>>
>>> +--cputype::
>>> +Only enable events on applying cpu with this type for hybrid 
>>> platform(e.g. core or atom).
>>> +For non-hybrid events, it should be no effect.
>>> +
>>>   --namespaces::
>>>   Record events of type PERF_RECORD_NAMESPACES.  This enables 
>>> 'cgroup_id' sort key.
>>>
>>> diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
>>> index 9a71f0330137..e1edd4e98358 100644
>>> --- a/tools/perf/builtin-record.c
>>> +++ b/tools/perf/builtin-record.c
>>> @@ -3183,6 +3183,9 @@ static struct option __record_options[] = {
>>>          OPT_INCR('v', "verbose", &verbose,
>>>                      "be more verbose (show counter open errors, etc)"),
>>>          OPT_BOOLEAN('q', "quiet", &quiet, "don't print any message"),
>>> +       OPT_CALLBACK(0, "cputype", &record.evlist, "hybrid cpu type",
>>> +                    "Only enable events on applying cpu with this 
>>> type for hybrid platform (e.g. core or atom)",
>>> +                    parse_hybrid_type),
>>>          OPT_BOOLEAN('s', "stat", &record.opts.inherit_stat,
>>>                      "per thread counts"),
>>>          OPT_BOOLEAN('d', "data", &record.opts.sample_address, 
>>> "Record the sample addresses"),
>>> diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
>>> index 4ce87a8eb7d7..0d95b29273f4 100644
>>> --- a/tools/perf/builtin-stat.c
>>> +++ b/tools/perf/builtin-stat.c
>>> @@ -1184,26 +1184,6 @@ static int parse_stat_cgroups(const struct 
>>> option *opt,
>>>          return parse_cgroups(opt, str, unset);
>>>   }
>>>
>>> -static int parse_hybrid_type(const struct option *opt,
>>> -                            const char *str,
>>> -                            int unset __maybe_unused)
>>> -{
>>> -       struct evlist *evlist = *(struct evlist **)opt->value;
>>> -
>>> -       if (!list_empty(&evlist->core.entries)) {
>>> -               fprintf(stderr, "Must define cputype before 
>>> events/metrics\n");
>>> -               return -1;
>>> -       }
>>> -
>>> -       evlist->hybrid_pmu_name = perf_pmu__hybrid_type_to_pmu(str);
>>> -       if (!evlist->hybrid_pmu_name) {
>>> -               fprintf(stderr, "--cputype %s is not supported!\n", 
>>> str);
>>> -               return -1;
>>> -       }
>>> -
>>> -       return 0;
>>> -}
>>> -
>>>   static struct option stat_options[] = {
>>>          OPT_BOOLEAN('T', "transaction", &transaction_run,
>>>                      "hardware transaction statistics"),
>>> diff --git a/tools/perf/util/pmu-hybrid.c b/tools/perf/util/pmu-hybrid.c
>>> index f51ccaac60ee..5c490b5201b7 100644
>>> --- a/tools/perf/util/pmu-hybrid.c
>>> +++ b/tools/perf/util/pmu-hybrid.c
>>> @@ -13,6 +13,7 @@
>>>   #include <stdarg.h>
>>>   #include <locale.h>
>>>   #include <api/fs/fs.h>
>>> +#include "util/evlist.h"
>>>   #include "fncache.h"
>>>   #include "pmu-hybrid.h"
>>>
>>> @@ -87,3 +88,21 @@ char *perf_pmu__hybrid_type_to_pmu(const char *type)
>>>          free(pmu_name);
>>>          return NULL;
>>>   }
>>> +
>>> +int parse_hybrid_type(const struct option *opt, const char *str, int 
>>> unset __maybe_unused)
>>> +{
>>> +       struct evlist *evlist = *(struct evlist **)opt->value;
>>> +
>>> +       if (!list_empty(&evlist->core.entries)) {
>>> +               fprintf(stderr, "Must define cputype before 
>>> events/metrics\n");
>>> +               return -1;
>>> +       }
>>> +
>>> +       evlist->hybrid_pmu_name = perf_pmu__hybrid_type_to_pmu(str);
>>> +       if (!evlist->hybrid_pmu_name) {
>>> +               fprintf(stderr, "--cputype %s is not supported!\n", 
>>> str);
>>> +               return -1;
>>> +       }
>>> +
>>> +       return 0;
>>> +}
>>> diff --git a/tools/perf/util/pmu-hybrid.h b/tools/perf/util/pmu-hybrid.h
>>> index 2b186c26a43e..26101f134a3a 100644
>>> --- a/tools/perf/util/pmu-hybrid.h
>>> +++ b/tools/perf/util/pmu-hybrid.h
>>> @@ -5,6 +5,7 @@
>>>   #include <linux/perf_event.h>
>>>   #include <linux/compiler.h>
>>>   #include <linux/list.h>
>>> +#include <subcmd/parse-options.h>
>>>   #include <stdbool.h>
>>>   #include "pmu.h"
>>>
>>> @@ -18,6 +19,7 @@ bool perf_pmu__hybrid_mounted(const char *name);
>>>   struct perf_pmu *perf_pmu__find_hybrid_pmu(const char *name);
>>>   bool perf_pmu__is_hybrid(const char *name);
>>>   char *perf_pmu__hybrid_type_to_pmu(const char *type);
>>> +int parse_hybrid_type(const struct option *opt, const char *str, int 
>>> unset __maybe_unused);
>>>
>>>   static inline int perf_pmu__hybrid_pmu_num(void)
>>>   {
>>> -- 
>>> 2.25.1
>>>
>