perf tools: Enable on a list of CPUs for hybrid

The 'perf record' and 'perf stat' commands have supported the option
'-C/--cpus' to count or collect only on the list of CPUs provided. This
option needs to be supported for hybrid as well.

For hybrid support, it needs to check that the cpu list are available
on hybrid PMU. One example for AlderLake, cpu0-7 is 'cpu_core', cpu8-11
is 'cpu_atom'.

Before:

  # perf stat -e cpu_core/cycles/ -C11 -- sleep 1

   Performance counter stats for 'CPU(s) 11':

     <not supported>      cpu_core/cycles/

         1.006179431 seconds time elapsed

The 'perf stat' command silently returned "<not supported>" without any
helpful information. It should error out pointing out that that cpu11
was not 'cpu_core'.

After:

  # perf stat -e cpu_core/cycles/ -C11 -- sleep 1
  WARNING: 11 isn't a 'cpu_core', please use a CPU list in the 'cpu_core' range (0-7)
  failed to use cpu list 11

We also need to support the events without pmu prefix specified.

  # perf stat -e cycles -C11 -- sleep 1
  WARNING: 11 isn't a 'cpu_core', please use a CPU list in the 'cpu_core' range (0-7)

   Performance counter stats for 'CPU(s) 11':

           1,067,373      cpu_atom/cycles/

         1.005544738 seconds time elapsed

The perf tool creates two cycles events automatically, cpu_core/cycles/ and
cpu_atom/cycles/. It checks that cpu11 is not 'cpu_core', then shows a warning
for cpu_core/cycles/ and only count the cpu_atom/cycles/.

If part of cpus are 'cpu_core' and part of cpus are 'cpu_atom', for example,

  # perf stat -e cycles -C0,11 -- sleep 1
  WARNING: use 0 in 'cpu_core' for 'cycles', skip other cpus in list.
  WARNING: use 11 in 'cpu_atom' for 'cycles', skip other cpus in list.

   Performance counter stats for 'CPU(s) 0,11':

           1,914,704      cpu_core/cycles/
           2,036,983      cpu_atom/cycles/

         1.005815641 seconds time elapsed

It now automatically selects cpu0 for cpu_core/cycles/, selects cpu11 for
cpu_atom/cycles/, and output with some warnings.

Some more complex examples,

  # perf stat -e cycles,instructions -C0,11 -- sleep 1
  WARNING: use 0 in 'cpu_core' for 'cycles', skip other cpus in list.
  WARNING: use 11 in 'cpu_atom' for 'cycles', skip other cpus in list.
  WARNING: use 0 in 'cpu_core' for 'instructions', skip other cpus in list.
  WARNING: use 11 in 'cpu_atom' for 'instructions', skip other cpus in list.

   Performance counter stats for 'CPU(s) 0,11':

           2,780,387      cpu_core/cycles/
           1,583,432      cpu_atom/cycles/
           3,957,277      cpu_core/instructions/
           1,167,089      cpu_atom/instructions/

         1.006005124 seconds time elapsed

  # perf stat -e cycles,cpu_atom/instructions/ -C0,11 -- sleep 1
  WARNING: use 0 in 'cpu_core' for 'cycles', skip other cpus in list.
  WARNING: use 11 in 'cpu_atom' for 'cycles', skip other cpus in list.
  WARNING: use 11 in 'cpu_atom' for 'cpu_atom/instructions/', skip other cpus in list.

   Performance counter stats for 'CPU(s) 0,11':

           3,290,301      cpu_core/cycles/
           1,953,073      cpu_atom/cycles/
           1,407,869      cpu_atom/instructions/

         1.006260912 seconds time elapsed

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https //lore.kernel.org/r/20210723063433.7318-4-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 548c1dbde6c5..cc801fecf079 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -2854,6 +2854,13 @@ int cmd_record(int argc, const char **argv)
 	/* Enable ignoring missing threads when -u/-p option is defined. */
 	rec->opts.ignore_missing_thread = rec->opts.target.uid != UINT_MAX || rec->opts.target.pid;
 
+	if (evlist__fix_hybrid_cpus(rec->evlist, rec->opts.target.cpu_list)) {
+		pr_err("failed to use cpu list %s\n",
+		       rec->opts.target.cpu_list);
+		goto out;
+	}
+
+	rec->opts.target.hybrid = perf_pmu__has_hybrid();
 	err = -ENOMEM;
 	if (evlist__create_maps(rec->evlist, &rec->opts.target) < 0)
 		usage_with_options(record_usage, record_options);