perf bpf_counter: Fix handling of cpumap fixing hybrid

Don't open evsels on all CPUs, open them just on the CPUs they
support. This avoids opening say an e-core event on a p-core and
getting a failure - achieve this by getting rid of the "all_cpu_map".

In install_pe functions don't use the cpu_map_idx as a CPU number,
translate the cpu_map_idx, which is a dense index into the cpu_map
skipping holes at the beginning, to a proper CPU number.

Before:
```
$ perf stat --bpf-counters -a -e cycles,instructions -- sleep 1

 Performance counter stats for 'system wide':

   <not supported>      cpu_atom/cycles/
       566,270,672      cpu_core/cycles/
   <not supported>      cpu_atom/instructions/
       572,792,836      cpu_core/instructions/           #    1.01  insn per cycle

       1.001595384 seconds time elapsed
```

After:
```
$ perf stat --bpf-counters -a -e cycles,instructions -- sleep 1

 Performance counter stats for 'system wide':

       443,299,201      cpu_atom/cycles/
     1,233,919,737      cpu_core/cycles/
       213,634,112      cpu_atom/instructions/           #    0.48  insn per cycle
     2,758,965,527      cpu_core/instructions/           #    2.24  insn per cycle

       1.001699485 seconds time elapsed
```

Fixes: 7fac83aaf2eecc9e ("perf stat: Introduce 'bperf' to share hardware PMCs with BPF")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: bpf@vger.kernel.org
Cc: Gabriele Monaco <gmonaco@redhat.com>
Cc: Howard Chu <howardchu95@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@linaro.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Tengda Wu <wutengda@huaweicloud.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/bpf_counter.c b/tools/perf/util/bpf_counter.c
index 1c6cb5ea077e640003754c697478782de3fa0bc0..ca5d01b9017dbac9b3b71c91ca18015b88ef7d11 100644 (file)
--- a/tools/perf/util/bpf_counter.c
+++ b/tools/perf/util/bpf_counter.c
@@ -336,6 +336,7 @@ static int bpf_program_profiler__install_pe(struct evsel *evsel, int cpu_map_idx
 {
        struct bpf_prog_profiler_bpf *skel;
        struct bpf_counter *counter;
+       int cpu = perf_cpu_map__cpu(evsel->core.cpus, cpu_map_idx).cpu;
        int ret;
 
        list_for_each_entry(counter, &evsel->bpf_counter_list, list) {
@@ -343,7 +344,7 @@ static int bpf_program_profiler__install_pe(struct evsel *evsel, int cpu_map_idx
                assert(skel != NULL);
 
                ret = bpf_map_update_elem(bpf_map__fd(skel->maps.events),
-                                         &cpu_map_idx, &fd, BPF_ANY);
+                                         &cpu, &fd, BPF_ANY);
                if (ret)
                        return ret;
        }
@@ -451,7 +452,6 @@ static int bperf_check_target(struct evsel *evsel,
        return 0;
 }
 
-static struct perf_cpu_map *all_cpu_map;
 static __u32 filter_entry_cnt;
 
 static int bperf_reload_leader_program(struct evsel *evsel, int attr_map_fd,
@@ -495,7 +495,7 @@ static int bperf_reload_leader_program(struct evsel *evsel, int attr_map_fd,
         * following evsel__open_per_cpu call
         */
        evsel->leader_skel = skel;
-       evsel__open_per_cpu(evsel, all_cpu_map, -1);
+       evsel__open(evsel, evsel->core.cpus, evsel->core.threads);
 
 out:
        bperf_leader_bpf__destroy(skel);
@@ -533,12 +533,6 @@ static int bperf__load(struct evsel *evsel, struct target *target)
        if (bperf_check_target(evsel, target, &filter_type, &filter_entry_cnt))
                return -1;
 
-       if (!all_cpu_map) {
-               all_cpu_map = perf_cpu_map__new_online_cpus();
-               if (!all_cpu_map)
-                       return -1;
-       }
-
        evsel->bperf_leader_prog_fd = -1;
        evsel->bperf_leader_link_fd = -1;
 
@@ -656,9 +650,10 @@ out:
 static int bperf__install_pe(struct evsel *evsel, int cpu_map_idx, int fd)
 {
        struct bperf_leader_bpf *skel = evsel->leader_skel;
+       int cpu = perf_cpu_map__cpu(evsel->core.cpus, cpu_map_idx).cpu;
 
        return bpf_map_update_elem(bpf_map__fd(skel->maps.events),
-                                  &cpu_map_idx, &fd, BPF_ANY);
+                                  &cpu, &fd, BPF_ANY);
 }
 
 /*
@@ -667,13 +662,12 @@ static int bperf__install_pe(struct evsel *evsel, int cpu_map_idx, int fd)
  */
 static int bperf_sync_counters(struct evsel *evsel)
 {
-       int num_cpu, i, cpu;
+       struct perf_cpu cpu;
+       int idx;
+
+       perf_cpu_map__for_each_cpu(cpu, idx, evsel->core.cpus)
+               bperf_trigger_reading(evsel->bperf_leader_prog_fd, cpu.cpu);
 
-       num_cpu = perf_cpu_map__nr(all_cpu_map);
-       for (i = 0; i < num_cpu; i++) {
-               cpu = perf_cpu_map__cpu(all_cpu_map, i).cpu;
-               bperf_trigger_reading(evsel->bperf_leader_prog_fd, cpu);
-       }
        return 0;
 }
 

diff --git a/tools/perf/util/bpf_counter_cgroup.c b/tools/perf/util/bpf_counter_cgroup.c
index ed6a29b106b4e98c7c49a1ffa22dd5009045ff31..690be3ce3e1143b6d27e4aa6c7a189bff12e3ef7 100644 (file)
--- a/tools/perf/util/bpf_counter_cgroup.c
+++ b/tools/perf/util/bpf_counter_cgroup.c
@@ -186,7 +186,8 @@ static int bperf_cgrp__load(struct evsel *evsel,
 }
 
 static int bperf_cgrp__install_pe(struct evsel *evsel __maybe_unused,
-                                 int cpu __maybe_unused, int fd __maybe_unused)
+                                 int cpu_map_idx __maybe_unused,
+                                 int fd __maybe_unused)
 {
        /* nothing to do */
        return 0;