[PATCH V2 4/6] perf,tools: check and re-organize evsel cpu maps

From: Kan Liang
Date: Wed Apr 15 2015 - 11:09:08 EST


From: Kan Liang <kan.liang@xxxxxxxxx>

"-C" can be used to set cpu list. The cpu list may be incompatible with
event's cpumask. This patch discard the incompatible cpu. Only available
cpu can be stored in evsel->cpus->map.
If there is no cpu from cpu list compatible with event's cpumask. It
will error out.

Signed-off-by: Kan Liang <kan.liang@xxxxxxxxx>
---
tools/perf/builtin-top.c | 6 ++--
tools/perf/util/evlist.c | 72 ++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 75 insertions(+), 3 deletions(-)

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 1cb3436..5aba1b2 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -1220,9 +1220,6 @@ int cmd_top(int argc, const char **argv, const char *prefix __maybe_unused)
if (target__none(target))
target->system_wide = true;

- if (perf_evlist__create_maps(top.evlist, target) < 0)
- usage_with_options(top_usage, options);
-
if (!top.evlist->nr_entries &&
perf_evlist__add_default(top.evlist) < 0) {
ui__error("Not enough memory for event selector list\n");
@@ -1231,6 +1228,9 @@ int cmd_top(int argc, const char **argv, const char *prefix __maybe_unused)

symbol_conf.nr_events = top.evlist->nr_entries;

+ if (perf_evlist__create_maps(top.evlist, target) < 0)
+ usage_with_options(top_usage, options);
+
if (top.delay_secs < 1)
top.delay_secs = 1;

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index a065150..16319b4 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -1068,6 +1068,74 @@ int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages,
return perf_evlist__mmap_per_cpu(evlist, &mp);
}

+static int cmp_ids(const void *a, const void *b)
+{
+ return *(int *)a - *(int *)b;
+}
+
+/*
+ * Check evsel cpu map according to pmu cpumask and input
+ * Only available cpu can be stored in evsel->cpus->map.
+ */
+static int perf_evlist__check_evsel_cpus(struct perf_evlist *evlist)
+{
+ const struct cpu_map *cpus = evlist->cpus;
+ const int ncpus = cpu_map__nr(evlist->cpus);
+ struct perf_evsel *evsel;
+ int i, j, cpu_nr, tmp;
+
+ /* ensure we process id in increasing order */
+ qsort(evlist->cpus->map, evlist->cpus->nr, sizeof(int), cmp_ids);
+
+ evlist__for_each(evlist, evsel) {
+ if (evsel->cpus == cpus)
+ continue;
+
+ cpu_nr = 0;
+ j = 0;
+ for (i = 0; i < cpu_map__nr(evsel->cpus);) {
+
+ if (j >= ncpus) {
+ evsel->cpus->map[i++] = -1;
+ continue;
+ }
+ for (; j < ncpus; j++) {
+ if (cpus->map[j] < evsel->cpus->map[i])
+ continue;
+ if (cpus->map[j] == evsel->cpus->map[i]) {
+ cpu_nr++;
+ j++;
+ i++;
+ } else
+ evsel->cpus->map[i++] = -1;
+ break;
+ }
+ }
+
+ if (cpu_nr == cpu_map__nr(evsel->cpus))
+ continue;
+ if (cpu_nr == 0) {
+ perror("failed to create CPUs map, please check cpumask");
+ return -1;
+ }
+
+ tmp = 0;
+ for (i = 0; i < cpu_nr; i++) {
+ if (evsel->cpus->map[i] == -1) {
+ while (evsel->cpus->map[tmp] == -1) {
+ tmp++;
+ BUG_ON(tmp >= cpu_map__nr(evsel->cpus));
+ }
+ evsel->cpus->map[i] = evsel->cpus->map[tmp];
+ evsel->cpus->map[tmp] = -1;
+ }
+ tmp++;
+ }
+ evsel->cpus->nr = cpu_nr;
+ }
+ return 0;
+}
+
int perf_evlist__create_maps(struct perf_evlist *evlist, struct target *target)
{
struct cpu_map *cpus;
@@ -1088,6 +1156,10 @@ int perf_evlist__create_maps(struct perf_evlist *evlist, struct target *target)

perf_evlist__set_cpus(evlist, cpus);

+ if (target->cpu_list &&
+ (perf_evlist__check_evsel_cpus(evlist) < 0))
+ goto out_delete_threads;
+
return 0;

out_delete_threads:
--
1.8.3.1

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