[PATCH v3 01/35] perf cpumap: Add intersect function

Ian Rogers
2023-05-24T22:18:50Z

The merge function gives the union of two cpu maps. Add an intersect
function which is necessary, for example, when intersecting a PMUs
supported CPUs with user requested.

Signed-off-by: Ian Rogers <irogers@google.com>
---
tools/lib/perf/cpumap.c | 35 ++++++++++++++++++++++++
tools/lib/perf/include/perf/cpumap.h | 2 ++
tools/perf/tests/builtin-test.c | 1 +
tools/perf/tests/cpumap.c | 41 ++++++++++++++++++++++++++++
tools/perf/tests/tests.h | 1 +
5 files changed, 80 insertions(+)

diff --git a/tools/lib/perf/cpumap.c b/tools/lib/perf/cpumap.c
index 1229b18bcdb1..d4f3a1a12522 100644
--- a/tools/lib/perf/cpumap.c
+++ b/tools/lib/perf/cpumap.c
@@ -402,3 +402,38 @@ struct perf_cpu_map *perf_cpu_map__merge(struct perf_cpu_map *orig,
perf_cpu_map__put(orig);
return merged;
}
+
+struct perf_cpu_map *perf_cpu_map__intersect(struct perf_cpu_map *orig,
+ struct perf_cpu_map *other)
+{
+ struct perf_cpu *tmp_cpus;
+ int tmp_len;
+ int i, j, k;
+ struct perf_cpu_map *merged = NULL;
+
+ if (perf_cpu_map__is_subset(other, orig))
+ return perf_cpu_map__get(orig);
+ if (perf_cpu_map__is_subset(orig, other))
+ return perf_cpu_map__get(other);
+
+ tmp_len = max(orig->nr, other->nr);
+ tmp_cpus = malloc(tmp_len * sizeof(struct perf_cpu));
+ if (!tmp_cpus)
+ return NULL;
+
+ i = j = k = 0;
+ while (i < orig->nr && j < other->nr) {
+ if (orig->map[i].cpu < other->map[j].cpu)
+ i++;
+ else if (orig->map[i].cpu > other->map[j].cpu)
+ j++;
+ else {
+ j++;
+ tmp_cpus[k++] = orig->map[i++];
+ }
+ }
+ if (k)
+ merged = cpu_map__trim_new(k, tmp_cpus);
+ free(tmp_cpus);
+ return merged;
+}
diff --git a/tools/lib/perf/include/perf/cpumap.h b/tools/lib/perf/include/perf/cpumap.h
index 3f43f770cdac..0466c4216fbb 100644
--- a/tools/lib/perf/include/perf/cpumap.h
+++ b/tools/lib/perf/include/perf/cpumap.h
@@ -20,6 +20,8 @@ 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 struct perf_cpu_map *perf_cpu_map__intersect(struct perf_cpu_map *orig,
+ struct perf_cpu_map *other);
LIBPERF_API void perf_cpu_map__put(struct perf_cpu_map *map);
LIBPERF_API struct perf_cpu 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 b89d69afcef0..eef400025fca 100644
--- a/tools/perf/tests/builtin-test.c
+++ b/tools/perf/tests/builtin-test.c
@@ -97,6 +97,7 @@ static struct test_suite *generic_tests[] = {
&suite__backward_ring_buffer,
&suite__cpu_map_print,
&suite__cpu_map_merge,
+ &suite__cpu_map_intersect,
&suite__sdt_event,
&suite__is_printable_array,
&suite__bitmap_print,
diff --git a/tools/perf/tests/cpumap.c b/tools/perf/tests/cpumap.c
index b1a924314e09..92232978fe5e 100644
--- a/tools/perf/tests/cpumap.c
+++ b/tools/perf/tests/cpumap.c
@@ -171,6 +171,47 @@ static int test__cpu_map_merge(struct test_suite *test __maybe_unused, int subte
return 0;
}

+static int __test__cpu_map_intersect(const char *lhs, const char *rhs, int nr, const char *expected)
+{
+ struct perf_cpu_map *a = perf_cpu_map__new(lhs);
+ struct perf_cpu_map *b = perf_cpu_map__new(rhs);
+ struct perf_cpu_map *c = perf_cpu_map__intersect(a, b);
+ char buf[100];
+
+ TEST_ASSERT_EQUAL("failed to intersect map: bad nr", perf_cpu_map__nr(c), nr);
+ cpu_map__snprint(c, buf, sizeof(buf));
+ TEST_ASSERT_VAL("failed to intersect map: bad result", !strcmp(buf, expected));
+ perf_cpu_map__put(a);
+ perf_cpu_map__put(b);
+ perf_cpu_map__put(c);
+ return 0;
+}
+
+static int test__cpu_map_intersect(struct test_suite *test __maybe_unused,
+ int subtest __maybe_unused)
+{
+ int ret;
+
+ ret = __test__cpu_map_intersect("4,2,1", "4,5,7", 1, "4");
+ if (ret)
+ return ret;
+ ret = __test__cpu_map_intersect("1-8", "6-9", 3, "6-8");
+ if (ret)
+ return ret;
+ ret = __test__cpu_map_intersect("1-8,12-20", "6-9,15", 4, "6-8,15");
+ if (ret)
+ return ret;
+ ret = __test__cpu_map_intersect("4,2,1", "1", 1, "1");
+ if (ret)
+ return ret;
+ ret = __test__cpu_map_intersect("1", "4,2,1", 1, "1");
+ if (ret)
+ return ret;
+ ret = __test__cpu_map_intersect("1", "1", 1, "1");
+ return ret;
+}
+
DEFINE_SUITE("Synthesize cpu map", cpu_map_synthesize);
DEFINE_SUITE("Print cpu map", cpu_map_print);
DEFINE_SUITE("Merge cpu map", cpu_map_merge);
+DEFINE_SUITE("Intersect cpu map", cpu_map_intersect);
diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
index 9a0f3904e53d..b4e54f08bc39 100644
--- a/tools/perf/tests/tests.h
+++ b/tools/perf/tests/tests.h
@@ -127,6 +127,7 @@ DECLARE_SUITE(event_times);
DECLARE_SUITE(backward_ring_buffer);
DECLARE_SUITE(cpu_map_print);
DECLARE_SUITE(cpu_map_merge);
+DECLARE_SUITE(cpu_map_intersect);
DECLARE_SUITE(sdt_event);
DECLARE_SUITE(is_printable_array);
DECLARE_SUITE(bitmap_print);
--
2.40.1.698.g37aff9b760-goog