Re: [PATCH v4 14/35] perf evlist: Remove __evlist__add_default

[Ian Rogers <irogers@google.com>]

On Fri, May 26, 2023 at 6:45 PM Arnaldo Carvalho de Melo
<acme@kernel.org> wrote:
>
> Em Fri, May 26, 2023 at 02:53:49PM -0700, Ian Rogers escreveu:
> > __evlist__add_default adds a cycles event to a typically empty evlist
> > and was extended for hybrid with evlist__add_default_hybrid, as more
> > than 1 PMU was necessary. Rather than have dedicated logic for the
> > cycles event, this change switches to parsing 'cycles:P' which will
> > handle wildcarding the PMUs appropriately for hybrid.
>
> I think I reported this earlier, but at this point 'perf test python'
> breaks, I fixed it in the tmp.perf-tools-next:
>
>  19: 'import perf' in python                                         : FAILED!
> ⬢[acme@toolbox perf-tools-next]$ git log --oneline -1
> fe4f622c4fc7a02a (HEAD) perf evlist: Remove __evlist__add_default
> ⬢[acme@toolbox perf-tools-next]$
> ⬢[acme@toolbox perf-tools-next]$ perf test -v python
> Couldn't bump rlimit(MEMLOCK), failures may take place when creating BPF maps, etc
>  19: 'import perf' in python                                         :
> --- start ---
> test child forked, pid 2976621
> python usage test: "echo "import sys ; sys.path.append('/tmp/build/perf-tools-next/python'); import perf" | '/usr/bin/python3' "
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
> ImportError: /tmp/build/perf-tools-next/python/perf.cpython-310-x86_64-linux-gnu.so: undefined symbol: parse_event
> test child finished with -1
> ---- end ----
> 'import perf' in python: FAILED!
> ⬢[acme@toolbox perf-tools-next]$
>
> Probably there will be a few more cases in the next patches, please
> check.

I'll rebase and resend. I needed to add:
https://lore.kernel.org/lkml/20230527055517.2711487-1-irogers@google.com/
to repro the failure. The test was passing without it.

Thanks,
Ian

> - Arnaldo
>
> > Signed-off-by: Ian Rogers <irogers@google.com>
> > Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
> > ---
> >  tools/perf/arch/x86/util/evsel.c | 20 --------------
> >  tools/perf/builtin-record.c      | 13 +++------
> >  tools/perf/builtin-top.c         | 10 ++++---
> >  tools/perf/util/evlist-hybrid.c  | 25 -----------------
> >  tools/perf/util/evlist-hybrid.h  |  1 -
> >  tools/perf/util/evlist.c         | 22 ++++++---------
> >  tools/perf/util/evlist.h         |  7 -----
> >  tools/perf/util/evsel.c          | 46 --------------------------------
> >  tools/perf/util/evsel.h          |  3 ---
> >  9 files changed, 17 insertions(+), 130 deletions(-)
> >
> > diff --git a/tools/perf/arch/x86/util/evsel.c b/tools/perf/arch/x86/util/evsel.c
> > index ea3972d785d1..153cdca94cd4 100644
> > --- a/tools/perf/arch/x86/util/evsel.c
> > +++ b/tools/perf/arch/x86/util/evsel.c
> > @@ -16,26 +16,6 @@ void arch_evsel__set_sample_weight(struct evsel *evsel)
> >       evsel__set_sample_bit(evsel, WEIGHT_STRUCT);
> >  }
> >
> > -void arch_evsel__fixup_new_cycles(struct perf_event_attr *attr)
> > -{
> > -     struct perf_env env = { .total_mem = 0, } ;
> > -
> > -     if (!perf_env__cpuid(&env))
> > -             return;
> > -
> > -     /*
> > -      * On AMD, precise cycles event sampling internally uses IBS pmu.
> > -      * But IBS does not have filtering capabilities and perf by default
> > -      * sets exclude_guest = 1. This makes IBS pmu event init fail and
> > -      * thus perf ends up doing non-precise sampling. Avoid it by clearing
> > -      * exclude_guest.
> > -      */
> > -     if (env.cpuid && strstarts(env.cpuid, "AuthenticAMD"))
> > -             attr->exclude_guest = 0;
> > -
> > -     free(env.cpuid);
> > -}
> > -
> >  /* Check whether the evsel's PMU supports the perf metrics */
> >  bool evsel__sys_has_perf_metrics(const struct evsel *evsel)
> >  {
> > diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
> > index 88f7b4241153..d80b54a6f450 100644
> > --- a/tools/perf/builtin-record.c
> > +++ b/tools/perf/builtin-record.c
> > @@ -4161,18 +4161,11 @@ int cmd_record(int argc, const char **argv)
> >               record.opts.tail_synthesize = true;
> >
> >       if (rec->evlist->core.nr_entries == 0) {
> > -             if (perf_pmu__has_hybrid()) {
> > -                     err = evlist__add_default_hybrid(rec->evlist,
> > -                                                      !record.opts.no_samples);
> > -             } else {
> > -                     err = __evlist__add_default(rec->evlist,
> > -                                                 !record.opts.no_samples);
> > -             }
> > +             bool can_profile_kernel = perf_event_paranoid_check(1);
> >
> > -             if (err < 0) {
> > -                     pr_err("Not enough memory for event selector list\n");
> > +             err = parse_event(rec->evlist, can_profile_kernel ? "cycles:P" : "cycles:Pu");
> > +             if (err)
> >                       goto out;
> > -             }
> >       }
> >
> >       if (rec->opts.target.tid && !rec->opts.no_inherit_set)
> > diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
> > index 48ee49e95c5e..27a7f068207d 100644
> > --- a/tools/perf/builtin-top.c
> > +++ b/tools/perf/builtin-top.c
> > @@ -1653,10 +1653,12 @@ int cmd_top(int argc, const char **argv)
> >       if (annotate_check_args(&top.annotation_opts) < 0)
> >               goto out_delete_evlist;
> >
> > -     if (!top.evlist->core.nr_entries &&
> > -         evlist__add_default(top.evlist) < 0) {
> > -             pr_err("Not enough memory for event selector list\n");
> > -             goto out_delete_evlist;
> > +     if (!top.evlist->core.nr_entries) {
> > +             bool can_profile_kernel = perf_event_paranoid_check(1);
> > +             int err = parse_event(top.evlist, can_profile_kernel ? "cycles:P" : "cycles:Pu");
> > +
> > +             if (err)
> > +                     goto out_delete_evlist;
> >       }
> >
> >       status = evswitch__init(&top.evswitch, top.evlist, stderr);
> > diff --git a/tools/perf/util/evlist-hybrid.c b/tools/perf/util/evlist-hybrid.c
> > index 0f59c80f27b2..64f78d06fe19 100644
> > --- a/tools/perf/util/evlist-hybrid.c
> > +++ b/tools/perf/util/evlist-hybrid.c
> > @@ -16,31 +16,6 @@
> >  #include <perf/evsel.h>
> >  #include <perf/cpumap.h>
> >
> > -int evlist__add_default_hybrid(struct evlist *evlist, bool precise)
> > -{
> > -     struct evsel *evsel;
> > -     struct perf_pmu *pmu;
> > -     __u64 config;
> > -     struct perf_cpu_map *cpus;
> > -
> > -     perf_pmu__for_each_hybrid_pmu(pmu) {
> > -             config = PERF_COUNT_HW_CPU_CYCLES |
> > -                      ((__u64)pmu->type << PERF_PMU_TYPE_SHIFT);
> > -             evsel = evsel__new_cycles(precise, PERF_TYPE_HARDWARE,
> > -                                       config);
> > -             if (!evsel)
> > -                     return -ENOMEM;
> > -
> > -             cpus = perf_cpu_map__get(pmu->cpus);
> > -             evsel->core.cpus = cpus;
> > -             evsel->core.own_cpus = perf_cpu_map__get(cpus);
> > -             evsel->pmu_name = strdup(pmu->name);
> > -             evlist__add(evlist, evsel);
> > -     }
> > -
> > -     return 0;
> > -}
> > -
> >  bool evlist__has_hybrid(struct evlist *evlist)
> >  {
> >       struct evsel *evsel;
> > diff --git a/tools/perf/util/evlist-hybrid.h b/tools/perf/util/evlist-hybrid.h
> > index 4b000eda6626..0cded76eb344 100644
> > --- a/tools/perf/util/evlist-hybrid.h
> > +++ b/tools/perf/util/evlist-hybrid.h
> > @@ -7,7 +7,6 @@
> >  #include "evlist.h"
> >  #include <unistd.h>
> >
> > -int evlist__add_default_hybrid(struct evlist *evlist, bool precise);
> >  bool evlist__has_hybrid(struct evlist *evlist);
> >
> >  #endif /* __PERF_EVLIST_HYBRID_H */
> > diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
> > index 9dfa977193b3..63f8821a5395 100644
> > --- a/tools/perf/util/evlist.c
> > +++ b/tools/perf/util/evlist.c
> > @@ -93,8 +93,15 @@ struct evlist *evlist__new(void)
> >  struct evlist *evlist__new_default(void)
> >  {
> >       struct evlist *evlist = evlist__new();
> > +     bool can_profile_kernel;
> > +     int err;
> > +
> > +     if (!evlist)
> > +             return NULL;
> >
> > -     if (evlist && evlist__add_default(evlist)) {
> > +     can_profile_kernel = perf_event_paranoid_check(1);
> > +     err = parse_event(evlist, can_profile_kernel ? "cycles:P" : "cycles:Pu");
> > +     if (err) {
> >               evlist__delete(evlist);
> >               evlist = NULL;
> >       }
> > @@ -237,19 +244,6 @@ static void evlist__set_leader(struct evlist *evlist)
> >       perf_evlist__set_leader(&evlist->core);
> >  }
> >
> > -int __evlist__add_default(struct evlist *evlist, bool precise)
> > -{
> > -     struct evsel *evsel;
> > -
> > -     evsel = evsel__new_cycles(precise, PERF_TYPE_HARDWARE,
> > -                               PERF_COUNT_HW_CPU_CYCLES);
> > -     if (evsel == NULL)
> > -             return -ENOMEM;
> > -
> > -     evlist__add(evlist, evsel);
> > -     return 0;
> > -}
> > -
> >  static struct evsel *evlist__dummy_event(struct evlist *evlist)
> >  {
> >       struct perf_event_attr attr = {
> > diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
> > index 5e7ff44f3043..664c6bf7b3e0 100644
> > --- a/tools/perf/util/evlist.h
> > +++ b/tools/perf/util/evlist.h
> > @@ -100,13 +100,6 @@ void evlist__delete(struct evlist *evlist);
> >  void evlist__add(struct evlist *evlist, struct evsel *entry);
> >  void evlist__remove(struct evlist *evlist, struct evsel *evsel);
> >
> > -int __evlist__add_default(struct evlist *evlist, bool precise);
> > -
> > -static inline int evlist__add_default(struct evlist *evlist)
> > -{
> > -     return __evlist__add_default(evlist, true);
> > -}
> > -
> >  int evlist__add_attrs(struct evlist *evlist, struct perf_event_attr *attrs, size_t nr_attrs);
> >
> >  int __evlist__add_default_attrs(struct evlist *evlist,
> > diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
> > index 8c8f371ea2b5..1df8f967d2eb 100644
> > --- a/tools/perf/util/evsel.c
> > +++ b/tools/perf/util/evsel.c
> > @@ -316,48 +316,6 @@ struct evsel *evsel__new_idx(struct perf_event_attr *attr, int idx)
> >       return evsel;
> >  }
> >
> > -static bool perf_event_can_profile_kernel(void)
> > -{
> > -     return perf_event_paranoid_check(1);
> > -}
> > -
> > -struct evsel *evsel__new_cycles(bool precise __maybe_unused, __u32 type, __u64 config)
> > -{
> > -     struct perf_event_attr attr = {
> > -             .type   = type,
> > -             .config = config,
> > -             .exclude_kernel = !perf_event_can_profile_kernel(),
> > -     };
> > -     struct evsel *evsel;
> > -
> > -     event_attr_init(&attr);
> > -
> > -     /*
> > -      * Now let the usual logic to set up the perf_event_attr defaults
> > -      * to kick in when we return and before perf_evsel__open() is called.
> > -      */
> > -     evsel = evsel__new(&attr);
> > -     if (evsel == NULL)
> > -             goto out;
> > -
> > -     arch_evsel__fixup_new_cycles(&evsel->core.attr);
> > -
> > -     evsel->precise_max = true;
> > -
> > -     /* use asprintf() because free(evsel) assumes name is allocated */
> > -     if (asprintf(&evsel->name, "cycles%s%s%.*s",
> > -                  (attr.precise_ip || attr.exclude_kernel) ? ":" : "",
> > -                  attr.exclude_kernel ? "u" : "",
> > -                  attr.precise_ip ? attr.precise_ip + 1 : 0, "ppp") < 0)
> > -             goto error_free;
> > -out:
> > -     return evsel;
> > -error_free:
> > -     evsel__delete(evsel);
> > -     evsel = NULL;
> > -     goto out;
> > -}
> > -
> >  int copy_config_terms(struct list_head *dst, struct list_head *src)
> >  {
> >       struct evsel_config_term *pos, *tmp;
> > @@ -1131,10 +1089,6 @@ void __weak arch_evsel__set_sample_weight(struct evsel *evsel)
> >       evsel__set_sample_bit(evsel, WEIGHT);
> >  }
> >
> > -void __weak arch_evsel__fixup_new_cycles(struct perf_event_attr *attr __maybe_unused)
> > -{
> > -}
> > -
> >  void __weak arch__post_evsel_config(struct evsel *evsel __maybe_unused,
> >                                   struct perf_event_attr *attr __maybe_unused)
> >  {
> > diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
> > index df8928745fc6..429b172cc94d 100644
> > --- a/tools/perf/util/evsel.h
> > +++ b/tools/perf/util/evsel.h
> > @@ -243,8 +243,6 @@ static inline struct evsel *evsel__newtp(const char *sys, const char *name)
> >  }
> >  #endif
> >
> > -struct evsel *evsel__new_cycles(bool precise, __u32 type, __u64 config);
> > -
> >  #ifdef HAVE_LIBTRACEEVENT
> >  struct tep_event *event_format__new(const char *sys, const char *name);
> >  #endif
> > @@ -312,7 +310,6 @@ void __evsel__reset_sample_bit(struct evsel *evsel, enum perf_event_sample_forma
> >  void evsel__set_sample_id(struct evsel *evsel, bool use_sample_identifier);
> >
> >  void arch_evsel__set_sample_weight(struct evsel *evsel);
> > -void arch_evsel__fixup_new_cycles(struct perf_event_attr *attr);
> >  void arch__post_evsel_config(struct evsel *evsel, struct perf_event_attr *attr);
> >
> >  int evsel__set_filter(struct evsel *evsel, const char *filter);
> > --
> > 2.41.0.rc0.172.g3f132b7071-goog
> >
>
> --
>
> - Arnaldo