[PATCH v7 04/12] perf evlist: Maintain evlist->all_cpus

Andi Kleen
2019-11-16T05:53:27Z

From: Andi Kleen <ak@linux.intel.com>

Maintain a cpumap in the evlist that is the union of all the cpus
of the events.

This needs a cpumap merge operation, which is added together
with tests.

Signed-off-by: Andi Kleen <ak@linux.intel.com>

v2:
Add tests for cpu map merge
Fix handling of duplicates
Rename _update to _merge
Factor out sorting.
Fix handling of NULL maps in merge
v3:
Add comments and empty lines to _merge
---
tools/perf/lib/cpumap.c | 57 ++++++++++++++++++++++++
tools/perf/lib/evlist.c | 1 +
tools/perf/lib/include/internal/evlist.h | 1 +
tools/perf/lib/include/perf/cpumap.h | 2 +
tools/perf/tests/builtin-test.c | 5 +++
tools/perf/tests/cpumap.c | 16 +++++++
tools/perf/tests/tests.h | 1 +
7 files changed, 83 insertions(+)

diff --git a/tools/perf/lib/cpumap.c b/tools/perf/lib/cpumap.c
index d81656b4635e..f93f4e703e4c 100644
--- a/tools/perf/lib/cpumap.c
+++ b/tools/perf/lib/cpumap.c
@@ -286,3 +286,60 @@ int perf_cpu_map__max(struct perf_cpu_map *map)

return max;
}
+
+/*
+ * Merge two cpumaps
+ *
+ * orig either gets freed and replaced with a new map, or reused
+ * with no reference count change (similar to "realloc")
+ * other has its reference count increased.
+ */
+
+struct perf_cpu_map *perf_cpu_map__merge(struct perf_cpu_map *orig,
+ struct perf_cpu_map *other)
+{
+ int *tmp_cpus;
+ int tmp_len;
+ int i, j, k;
+ struct perf_cpu_map *merged;
+
+ if (!orig && !other)
+ return NULL;
+ if (!orig) {
+ perf_cpu_map__get(other);
+ return other;
+ }
+ if (!other)
+ return orig;
+ if (orig->nr == other->nr &&
+ !memcmp(orig->map, other->map, orig->nr * sizeof(int)))
+ return orig;
+
+ tmp_len = orig->nr + other->nr;
+ tmp_cpus = malloc(tmp_len * sizeof(int));
+ if (!tmp_cpus)
+ return NULL;
+
+ /* Standard merge algorithm from wikipedia */
+ i = j = k = 0;
+ while (i < orig->nr && j < other->nr) {
+ if (orig->map[i] <= other->map[j]) {
+ if (orig->map[i] == other->map[j])
+ j++;
+ tmp_cpus[k++] = orig->map[i++];
+ } else
+ tmp_cpus[k++] = other->map[j++];
+ }
+
+ while (i < orig->nr)
+ tmp_cpus[k++] = orig->map[i++];
+
+ while (j < other->nr)
+ tmp_cpus[k++] = other->map[j++];
+ assert(k <= tmp_len);
+
+ merged = cpu_map__trim_new(k, tmp_cpus);
+ free(tmp_cpus);
+ perf_cpu_map__put(orig);
+ return merged;
+}
diff --git a/tools/perf/lib/evlist.c b/tools/perf/lib/evlist.c
index 205ddbb80bc1..ae9e65aa2491 100644
--- a/tools/perf/lib/evlist.c
+++ b/tools/perf/lib/evlist.c
@@ -54,6 +54,7 @@ static void __perf_evlist__propagate_maps(struct perf_evlist *evlist,

perf_thread_map__put(evsel->threads);
evsel->threads = perf_thread_map__get(evlist->threads);
+ evlist->all_cpus = perf_cpu_map__merge(evlist->all_cpus, evsel->cpus);
}

static void perf_evlist__propagate_maps(struct perf_evlist *evlist)
diff --git a/tools/perf/lib/include/internal/evlist.h b/tools/perf/lib/include/internal/evlist.h
index a2fbccf1922f..74dc8c3f0b66 100644
--- a/tools/perf/lib/include/internal/evlist.h
+++ b/tools/perf/lib/include/internal/evlist.h
@@ -18,6 +18,7 @@ struct perf_evlist {
int nr_entries;
bool has_user_cpus;
struct perf_cpu_map *cpus;
+ struct perf_cpu_map *all_cpus;
struct perf_thread_map *threads;
int nr_mmaps;
size_t mmap_len;
diff --git a/tools/perf/lib/include/perf/cpumap.h b/tools/perf/lib/include/perf/cpumap.h
index ac9aa497f84a..6a17ad730cbc 100644
--- a/tools/perf/lib/include/perf/cpumap.h
+++ b/tools/perf/lib/include/perf/cpumap.h
@@ -12,6 +12,8 @@ LIBPERF_API struct perf_cpu_map *perf_cpu_map__dummy_new(void);
LIBPERF_API struct perf_cpu_map *perf_cpu_map__new(const char *cpu_list);
LIBPERF_API struct perf_cpu_map *perf_cpu_map__read(FILE *file);
LIBPERF_API struct perf_cpu_map *perf_cpu_map__get(struct perf_cpu_map *map);
+LIBPERF_API struct perf_cpu_map *perf_cpu_map__merge(struct perf_cpu_map *orig,
+ struct perf_cpu_map *other);
LIBPERF_API void perf_cpu_map__put(struct perf_cpu_map *map);
LIBPERF_API int perf_cpu_map__cpu(const struct perf_cpu_map *cpus, int idx);
LIBPERF_API int perf_cpu_map__nr(const struct perf_cpu_map *cpus);
diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
index 8b286e9b7549..5fa37cf7f283 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -259,6 +259,11 @@ static struct test generic_tests[] = {
.desc = "Print cpu map",
.func = test__cpu_map_print,
},
+ {
+ .desc = "Merge cpu map",
+ .func = test__cpu_map_merge,
+ },
+
{
.desc = "Probe SDT events",
.func = test__sdt_event,
diff --git a/tools/perf/tests/cpumap.c b/tools/perf/tests/cpumap.c
index 8a0d236202b0..4ac56741ac5f 100644
--- a/tools/perf/tests/cpumap.c
+++ b/tools/perf/tests/cpumap.c
@@ -120,3 +120,19 @@ int test__cpu_map_print(struct test *test __maybe_unused, int subtest __maybe_un
TEST_ASSERT_VAL("failed to convert map", cpu_map_print("1-10,12-20,22-30,32-40"));
return 0;
}
+
+int test__cpu_map_merge(struct test *test __maybe_unused, int subtest __maybe_unused)
+{
+ struct perf_cpu_map *a = perf_cpu_map__new("4,2,1");
+ struct perf_cpu_map *b = perf_cpu_map__new("4,5,7");
+ struct perf_cpu_map *c = perf_cpu_map__merge(a, b);
+ char buf[100];
+
+ TEST_ASSERT_VAL("failed to merge map: bad nr", c->nr == 5);
+ cpu_map__snprint(c, buf, sizeof(buf));
+ TEST_ASSERT_VAL("failed to merge map: bad result", !strcmp(buf, "1-2,4-5,7"));
+ perf_cpu_map__put(a);
+ perf_cpu_map__put(b);
+ perf_cpu_map__put(c);
+ return 0;
+}
diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
index 9837b6e93023..44b184fd869f 100644
--- a/tools/perf/tests/tests.h
+++ b/tools/perf/tests/tests.h
@@ -98,6 +98,7 @@ int test__event_update(struct test *test, int subtest);
int test__event_times(struct test *test, int subtest);
int test__backward_ring_buffer(struct test *test, int subtest);
int test__cpu_map_print(struct test *test, int subtest);
+int test__cpu_map_merge(struct test *test, int subtest);
int test__sdt_event(struct test *test, int subtest);
int test__is_printable_array(struct test *test, int subtest);
int test__bitmap_print(struct test *test, int subtest);
--
2.23.0