perf stat: Use affinity for enabling/disabling events

Restructure event enabling/disabling to use affinity, which
minimizes the number of IPIs needed.

Before on a large test case with 94 CPUs:

  % time     seconds  usecs/call     calls    errors syscall
  ------ ----------- ----------- --------- --------- ----------------
   54.65    1.899986          22     84812       660 ioctl

after:

   39.21    0.930451          10     84796       644 ioctl

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/20191121001522.180827-13-andi@firstfloor.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 096a4ea..1548237 100644 (file)
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -378,11 +378,28 @@ bool evsel__cpu_iter_skip(struct evsel *ev, int cpu)
 void evlist__disable(struct evlist *evlist)
 {
        struct evsel *pos;
+       struct affinity affinity;
+       int cpu, i;
+
+       if (affinity__setup(&affinity) < 0)
+               return;
+
+       evlist__for_each_cpu(evlist, i, cpu) {
+               affinity__set(&affinity, cpu);
 
+               evlist__for_each_entry(evlist, pos) {
+                       if (evsel__cpu_iter_skip(pos, cpu))
+                               continue;
+                       if (pos->disabled || !perf_evsel__is_group_leader(pos) || !pos->core.fd)
+                               continue;
+                       evsel__disable_cpu(pos, pos->cpu_iter - 1);
+               }
+       }
+       affinity__cleanup(&affinity);
        evlist__for_each_entry(evlist, pos) {
-               if (pos->disabled || !perf_evsel__is_group_leader(pos) || !pos->core.fd)
+               if (!perf_evsel__is_group_leader(pos) || !pos->core.fd)
                        continue;
-               evsel__disable(pos);
+               pos->disabled = true;
        }
 
        evlist->enabled = false;
@@ -391,11 +408,28 @@ void evlist__disable(struct evlist *evlist)
 void evlist__enable(struct evlist *evlist)
 {
        struct evsel *pos;
+       struct affinity affinity;
+       int cpu, i;
 
+       if (affinity__setup(&affinity) < 0)
+               return;
+
+       evlist__for_each_cpu(evlist, i, cpu) {
+               affinity__set(&affinity, cpu);
+
+               evlist__for_each_entry(evlist, pos) {
+                       if (evsel__cpu_iter_skip(pos, cpu))
+                               continue;
+                       if (!perf_evsel__is_group_leader(pos) || !pos->core.fd)
+                               continue;
+                       evsel__enable_cpu(pos, pos->cpu_iter - 1);
+               }
+       }
+       affinity__cleanup(&affinity);
        evlist__for_each_entry(evlist, pos) {
                if (!perf_evsel__is_group_leader(pos) || !pos->core.fd)
                        continue;
-               evsel__enable(pos);
+               pos->disabled = false;
        }
 
        evlist->enabled = true;