OpenSDV
/
original_kernel
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

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>
This commit is contained in:
Andi Kleen 2019-11-20 16:15:22 -08:00 committed by Arnaldo Carvalho de Melo
parent 363fb12189
commit 704e2f5b70
1 changed files with 37 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

40
tools/perf/util/evlist.c
View File

@ -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;