diff mbox series

[v4,03/35] perf cpumap: Add equal function

Message ID 20230526215410.2435674-4-irogers@google.com (mailing list archive)
State New, archived
Headers show
Series PMU refactoring and improvements | expand

Commit Message

Ian Rogers May 26, 2023, 9:53 p.m. UTC 
Equality is a useful property to compare after merging and
intersecting maps.

Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
---
 tools/lib/perf/cpumap.c              | 21 ++++++++++++++++
 tools/lib/perf/include/perf/cpumap.h |  2 ++
 tools/perf/tests/cpumap.c            | 37 ++++++++++++++++++++++++++++
 3 files changed, 60 insertions(+)

Comments

Arnaldo Carvalho de Melo May 27, 2023, 1:32 a.m. UTC | #1 
Em Fri, May 26, 2023 at 02:53:38PM -0700, Ian Rogers escreveu:
> Equality is a useful property to compare after merging and
> intersecting maps.
> 
> Signed-off-by: Ian Rogers <irogers@google.com>
> Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
> ---
>  tools/lib/perf/cpumap.c              | 21 ++++++++++++++++
>  tools/lib/perf/include/perf/cpumap.h |  2 ++
>  tools/perf/tests/cpumap.c            | 37 ++++++++++++++++++++++++++++
>  3 files changed, 60 insertions(+)
> 
> diff --git a/tools/lib/perf/cpumap.c b/tools/lib/perf/cpumap.c
> index d4f3a1a12522..48595a3ad69c 100644
> --- a/tools/lib/perf/cpumap.c
> +++ b/tools/lib/perf/cpumap.c
> @@ -321,6 +321,27 @@ bool perf_cpu_map__has(const struct perf_cpu_map *cpus, struct perf_cpu cpu)
>  	return perf_cpu_map__idx(cpus, cpu) != -1;
>  }
>  
> +bool perf_cpu_map__equal(const struct perf_cpu_map *lhs, const struct perf_cpu_map *rhs)
> +{
> +	int nr;
> +
> +	if (lhs == rhs)
> +		return true;
> +
> +	if (!lhs || !rhs)
> +		return false;
> +
> +	nr = perf_cpu_map__nr(lhs);
> +	if (nr != perf_cpu_map__nr(rhs))
> +		return false;
> +
> +	for (int idx = 0; idx < nr; idx++) {
> +		if (RC_CHK_ACCESS(lhs)->map[idx].cpu != RC_CHK_ACCESS(rhs)->map[idx].cpu)
> +			return false;

Don't we have an accessor to avoid this RC_CHK_ACCESS()-> access?

> +	}
> +	return true;
> +}
> +
>  struct perf_cpu perf_cpu_map__max(const struct perf_cpu_map *map)
>  {
>  	struct perf_cpu result = {
> diff --git a/tools/lib/perf/include/perf/cpumap.h b/tools/lib/perf/include/perf/cpumap.h
> index 0466c4216fbb..d0ae9552f8e2 100644
> --- a/tools/lib/perf/include/perf/cpumap.h
> +++ b/tools/lib/perf/include/perf/cpumap.h
> @@ -28,6 +28,8 @@ LIBPERF_API int perf_cpu_map__nr(const struct perf_cpu_map *cpus);
>  LIBPERF_API bool perf_cpu_map__empty(const struct perf_cpu_map *map);
>  LIBPERF_API struct perf_cpu perf_cpu_map__max(const struct perf_cpu_map *map);
>  LIBPERF_API bool perf_cpu_map__has(const struct perf_cpu_map *map, struct perf_cpu cpu);
> +LIBPERF_API bool perf_cpu_map__equal(const struct perf_cpu_map *lhs,
> +				     const struct perf_cpu_map *rhs);
>  
>  #define perf_cpu_map__for_each_cpu(cpu, idx, cpus)		\
>  	for ((idx) = 0, (cpu) = perf_cpu_map__cpu(cpus, idx);	\
> diff --git a/tools/perf/tests/cpumap.c b/tools/perf/tests/cpumap.c
> index 83805690c209..7730fc2ab40b 100644
> --- a/tools/perf/tests/cpumap.c
> +++ b/tools/perf/tests/cpumap.c
> @@ -211,11 +211,48 @@ static int test__cpu_map_intersect(struct test_suite *test __maybe_unused,
>  	return ret;
>  }
>  
> +static int test__cpu_map_equal(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
> +{
> +	struct perf_cpu_map *any = perf_cpu_map__dummy_new();
> +	struct perf_cpu_map *one = perf_cpu_map__new("1");
> +	struct perf_cpu_map *two = perf_cpu_map__new("2");
> +	struct perf_cpu_map *empty = perf_cpu_map__intersect(one, two);
> +	struct perf_cpu_map *pair = perf_cpu_map__new("1-2");
> +	struct perf_cpu_map *tmp;
> +	struct perf_cpu_map *maps[] = {empty, any, one, two, pair};
> +
> +	for (size_t i = 0; i < ARRAY_SIZE(maps); i++) {
> +		/* Maps equal themself. */
> +		TEST_ASSERT_VAL("equal", perf_cpu_map__equal(maps[i], maps[i]));
> +		for (size_t j = 0; j < ARRAY_SIZE(maps); j++) {
> +			/* Maps dont't equal each other. */
> +			if (i == j)
> +				continue;
> +			TEST_ASSERT_VAL("not equal", !perf_cpu_map__equal(maps[i], maps[j]));
> +		}
> +	}
> +
> +	/* Maps equal made maps. */
> +	tmp = perf_cpu_map__merge(perf_cpu_map__get(one), two);
> +	TEST_ASSERT_VAL("pair", perf_cpu_map__equal(pair, tmp));
> +	perf_cpu_map__put(tmp);
> +
> +	tmp = perf_cpu_map__intersect(pair, one);
> +	TEST_ASSERT_VAL("one", perf_cpu_map__equal(one, tmp));
> +	perf_cpu_map__put(tmp);
> +
> +	for (size_t i = 0; i < ARRAY_SIZE(maps); i++)
> +		perf_cpu_map__put(maps[i]);
> +
> +	return TEST_OK;
> +}
> +
>  static struct test_case tests__cpu_map[] = {
>  	TEST_CASE("Synthesize cpu map", cpu_map_synthesize),
>  	TEST_CASE("Print cpu map", cpu_map_print),
>  	TEST_CASE("Merge cpu map", cpu_map_merge),
>  	TEST_CASE("Intersect cpu map", cpu_map_intersect),
> +	TEST_CASE("Equal cpu map", cpu_map_equal),
>  	{	.name = NULL, }
>  };
>  
> -- 
> 2.41.0.rc0.172.g3f132b7071-goog
>
Arnaldo Carvalho de Melo May 27, 2023, 1:40 a.m. UTC | #2 
Em Fri, May 26, 2023 at 10:32:12PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Fri, May 26, 2023 at 02:53:38PM -0700, Ian Rogers escreveu:
> > Equality is a useful property to compare after merging and
> > intersecting maps.
> > 
> > Signed-off-by: Ian Rogers <irogers@google.com>
> > Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
> > ---
> >  tools/lib/perf/cpumap.c              | 21 ++++++++++++++++
> >  tools/lib/perf/include/perf/cpumap.h |  2 ++
> >  tools/perf/tests/cpumap.c            | 37 ++++++++++++++++++++++++++++
> >  3 files changed, 60 insertions(+)
> > 
> > diff --git a/tools/lib/perf/cpumap.c b/tools/lib/perf/cpumap.c
> > index d4f3a1a12522..48595a3ad69c 100644
> > --- a/tools/lib/perf/cpumap.c
> > +++ b/tools/lib/perf/cpumap.c
> > @@ -321,6 +321,27 @@ bool perf_cpu_map__has(const struct perf_cpu_map *cpus, struct perf_cpu cpu)
> >  	return perf_cpu_map__idx(cpus, cpu) != -1;
> >  }
> >  
> > +bool perf_cpu_map__equal(const struct perf_cpu_map *lhs, const struct perf_cpu_map *rhs)
> > +{
> > +	int nr;
> > +
> > +	if (lhs == rhs)
> > +		return true;
> > +
> > +	if (!lhs || !rhs)
> > +		return false;
> > +
> > +	nr = perf_cpu_map__nr(lhs);
> > +	if (nr != perf_cpu_map__nr(rhs))
> > +		return false;
> > +
> > +	for (int idx = 0; idx < nr; idx++) {
> > +		if (RC_CHK_ACCESS(lhs)->map[idx].cpu != RC_CHK_ACCESS(rhs)->map[idx].cpu)
> > +			return false;
> 
> Don't we have an accessor to avoid this RC_CHK_ACCESS()-> access?
 
 In the following patch you use it:

+bool perf_cpu_map__has_any_cpu(const struct perf_cpu_map *map)
+{
+       return map && perf_cpu_map__cpu(map, 0).cpu == -1;
+}

But it does extra checks you did already:

struct perf_cpu perf_cpu_map__cpu(const struct perf_cpu_map *cpus, int idx)
{
        struct perf_cpu result = {
                .cpu = -1
        };

        if (cpus && idx < RC_CHK_ACCESS(cpus)->nr)
                return RC_CHK_ACCESS(cpus)->map[idx];

        return result;
}

Usually we have:

struct perf_cpu __perf_cpu_map__cpu(const struct perf_cpu_map *cpus, int idx)
{
	return RC_CHK_ACCESS(cpus)->map[idx];
}

struct perf_cpu perf_cpu_map__cpu(const struct perf_cpu_map *cpus, int idx)
{
        struct perf_cpu result = {
                .cpu = -1
        };

        if (cpus && idx < __perf_cpu_map__nr(cpus))
                return __perf_cpu_map__cpu(cpus, idx);

        return result;
}

Then you would have:

bool perf_cpu_map__equal(const struct perf_cpu_map *lhs, const struct perf_cpu_map *rhs)
{
	int nr;

	if (lhs == rhs)
		return true;

	if (!lhs || !rhs)
		return false;

	nr = __perf_cpu_map__nr(lhs);  // no need to check lhs again for NULL
	if (nr != __perf_cpu_map__nr(rhs)) // ditto for rhs
		return false;

	for (int idx = 0; idx < nr; idx++) {
		if (__perf_cpu_map__cpu(lhs, idx)->cpu != __perf_cpu_map__cpu(rhs, idx)->cpu)
			return false;


> > +	}
> > +	return true;
> > +}
> > +
> >  struct perf_cpu perf_cpu_map__max(const struct perf_cpu_map *map)
> >  {
> >  	struct perf_cpu result = {
> > diff --git a/tools/lib/perf/include/perf/cpumap.h b/tools/lib/perf/include/perf/cpumap.h
> > index 0466c4216fbb..d0ae9552f8e2 100644
> > --- a/tools/lib/perf/include/perf/cpumap.h
> > +++ b/tools/lib/perf/include/perf/cpumap.h
> > @@ -28,6 +28,8 @@ LIBPERF_API int perf_cpu_map__nr(const struct perf_cpu_map *cpus);
> >  LIBPERF_API bool perf_cpu_map__empty(const struct perf_cpu_map *map);
> >  LIBPERF_API struct perf_cpu perf_cpu_map__max(const struct perf_cpu_map *map);
> >  LIBPERF_API bool perf_cpu_map__has(const struct perf_cpu_map *map, struct perf_cpu cpu);
> > +LIBPERF_API bool perf_cpu_map__equal(const struct perf_cpu_map *lhs,
> > +				     const struct perf_cpu_map *rhs);
> >  
> >  #define perf_cpu_map__for_each_cpu(cpu, idx, cpus)		\
> >  	for ((idx) = 0, (cpu) = perf_cpu_map__cpu(cpus, idx);	\
> > diff --git a/tools/perf/tests/cpumap.c b/tools/perf/tests/cpumap.c
> > index 83805690c209..7730fc2ab40b 100644
> > --- a/tools/perf/tests/cpumap.c
> > +++ b/tools/perf/tests/cpumap.c
> > @@ -211,11 +211,48 @@ static int test__cpu_map_intersect(struct test_suite *test __maybe_unused,
> >  	return ret;
> >  }
> >  
> > +static int test__cpu_map_equal(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
> > +{
> > +	struct perf_cpu_map *any = perf_cpu_map__dummy_new();
> > +	struct perf_cpu_map *one = perf_cpu_map__new("1");
> > +	struct perf_cpu_map *two = perf_cpu_map__new("2");
> > +	struct perf_cpu_map *empty = perf_cpu_map__intersect(one, two);
> > +	struct perf_cpu_map *pair = perf_cpu_map__new("1-2");
> > +	struct perf_cpu_map *tmp;
> > +	struct perf_cpu_map *maps[] = {empty, any, one, two, pair};
> > +
> > +	for (size_t i = 0; i < ARRAY_SIZE(maps); i++) {
> > +		/* Maps equal themself. */
> > +		TEST_ASSERT_VAL("equal", perf_cpu_map__equal(maps[i], maps[i]));
> > +		for (size_t j = 0; j < ARRAY_SIZE(maps); j++) {
> > +			/* Maps dont't equal each other. */
> > +			if (i == j)
> > +				continue;
> > +			TEST_ASSERT_VAL("not equal", !perf_cpu_map__equal(maps[i], maps[j]));
> > +		}
> > +	}
> > +
> > +	/* Maps equal made maps. */
> > +	tmp = perf_cpu_map__merge(perf_cpu_map__get(one), two);
> > +	TEST_ASSERT_VAL("pair", perf_cpu_map__equal(pair, tmp));
> > +	perf_cpu_map__put(tmp);
> > +
> > +	tmp = perf_cpu_map__intersect(pair, one);
> > +	TEST_ASSERT_VAL("one", perf_cpu_map__equal(one, tmp));
> > +	perf_cpu_map__put(tmp);
> > +
> > +	for (size_t i = 0; i < ARRAY_SIZE(maps); i++)
> > +		perf_cpu_map__put(maps[i]);
> > +
> > +	return TEST_OK;
> > +}
> > +
> >  static struct test_case tests__cpu_map[] = {
> >  	TEST_CASE("Synthesize cpu map", cpu_map_synthesize),
> >  	TEST_CASE("Print cpu map", cpu_map_print),
> >  	TEST_CASE("Merge cpu map", cpu_map_merge),
> >  	TEST_CASE("Intersect cpu map", cpu_map_intersect),
> > +	TEST_CASE("Equal cpu map", cpu_map_equal),
> >  	{	.name = NULL, }
> >  };
> >  
> > -- 
> > 2.41.0.rc0.172.g3f132b7071-goog
> > 
> 
> -- 
> 
> - Arnaldo
Ian Rogers May 27, 2023, 6:05 a.m. UTC | #3 
On Fri, May 26, 2023 at 6:40 PM Arnaldo Carvalho de Melo
<acme@kernel.org> wrote:
>
> Em Fri, May 26, 2023 at 10:32:12PM -0300, Arnaldo Carvalho de Melo escreveu:
> > Em Fri, May 26, 2023 at 02:53:38PM -0700, Ian Rogers escreveu:
> > > Equality is a useful property to compare after merging and
> > > intersecting maps.
> > >
> > > Signed-off-by: Ian Rogers <irogers@google.com>
> > > Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
> > > ---
> > >  tools/lib/perf/cpumap.c              | 21 ++++++++++++++++
> > >  tools/lib/perf/include/perf/cpumap.h |  2 ++
> > >  tools/perf/tests/cpumap.c            | 37 ++++++++++++++++++++++++++++
> > >  3 files changed, 60 insertions(+)
> > >
> > > diff --git a/tools/lib/perf/cpumap.c b/tools/lib/perf/cpumap.c
> > > index d4f3a1a12522..48595a3ad69c 100644
> > > --- a/tools/lib/perf/cpumap.c
> > > +++ b/tools/lib/perf/cpumap.c
> > > @@ -321,6 +321,27 @@ bool perf_cpu_map__has(const struct perf_cpu_map *cpus, struct perf_cpu cpu)
> > >     return perf_cpu_map__idx(cpus, cpu) != -1;
> > >  }
> > >
> > > +bool perf_cpu_map__equal(const struct perf_cpu_map *lhs, const struct perf_cpu_map *rhs)
> > > +{
> > > +   int nr;
> > > +
> > > +   if (lhs == rhs)
> > > +           return true;
> > > +
> > > +   if (!lhs || !rhs)
> > > +           return false;
> > > +
> > > +   nr = perf_cpu_map__nr(lhs);
> > > +   if (nr != perf_cpu_map__nr(rhs))
> > > +           return false;
> > > +
> > > +   for (int idx = 0; idx < nr; idx++) {
> > > +           if (RC_CHK_ACCESS(lhs)->map[idx].cpu != RC_CHK_ACCESS(rhs)->map[idx].cpu)
> > > +                   return false;
> >
> > Don't we have an accessor to avoid this RC_CHK_ACCESS()-> access?
>
>  In the following patch you use it:
>
> +bool perf_cpu_map__has_any_cpu(const struct perf_cpu_map *map)
> +{
> +       return map && perf_cpu_map__cpu(map, 0).cpu == -1;
> +}
>
> But it does extra checks you did already:
>
> struct perf_cpu perf_cpu_map__cpu(const struct perf_cpu_map *cpus, int idx)
> {
>         struct perf_cpu result = {
>                 .cpu = -1
>         };
>
>         if (cpus && idx < RC_CHK_ACCESS(cpus)->nr)
>                 return RC_CHK_ACCESS(cpus)->map[idx];
>
>         return result;
> }
>
> Usually we have:
>
> struct perf_cpu __perf_cpu_map__cpu(const struct perf_cpu_map *cpus, int idx)
> {
>         return RC_CHK_ACCESS(cpus)->map[idx];
> }
>
> struct perf_cpu perf_cpu_map__cpu(const struct perf_cpu_map *cpus, int idx)
> {
>         struct perf_cpu result = {
>                 .cpu = -1
>         };
>
>         if (cpus && idx < __perf_cpu_map__nr(cpus))
>                 return __perf_cpu_map__cpu(cpus, idx);
>
>         return result;
> }
>
> Then you would have:
>
> bool perf_cpu_map__equal(const struct perf_cpu_map *lhs, const struct perf_cpu_map *rhs)
> {
>         int nr;
>
>         if (lhs == rhs)
>                 return true;
>
>         if (!lhs || !rhs)
>                 return false;
>
>         nr = __perf_cpu_map__nr(lhs);  // no need to check lhs again for NULL
>         if (nr != __perf_cpu_map__nr(rhs)) // ditto for rhs
>                 return false;
>
>         for (int idx = 0; idx < nr; idx++) {
>                 if (__perf_cpu_map__cpu(lhs, idx)->cpu != __perf_cpu_map__cpu(rhs, idx)->cpu)
>                         return false;
>

Thanks, I'll update for v5. Fwiw, on intersect, I keep forgetting to
mention that this was sent previously as:
https://lore.kernel.org/lkml/20220408035616.1356953-4-irogers@google.com/

Ian

> > > +   }
> > > +   return true;
> > > +}
> > > +
> > >  struct perf_cpu perf_cpu_map__max(const struct perf_cpu_map *map)
> > >  {
> > >     struct perf_cpu result = {
> > > diff --git a/tools/lib/perf/include/perf/cpumap.h b/tools/lib/perf/include/perf/cpumap.h
> > > index 0466c4216fbb..d0ae9552f8e2 100644
> > > --- a/tools/lib/perf/include/perf/cpumap.h
> > > +++ b/tools/lib/perf/include/perf/cpumap.h
> > > @@ -28,6 +28,8 @@ LIBPERF_API int perf_cpu_map__nr(const struct perf_cpu_map *cpus);
> > >  LIBPERF_API bool perf_cpu_map__empty(const struct perf_cpu_map *map);
> > >  LIBPERF_API struct perf_cpu perf_cpu_map__max(const struct perf_cpu_map *map);
> > >  LIBPERF_API bool perf_cpu_map__has(const struct perf_cpu_map *map, struct perf_cpu cpu);
> > > +LIBPERF_API bool perf_cpu_map__equal(const struct perf_cpu_map *lhs,
> > > +                                const struct perf_cpu_map *rhs);
> > >
> > >  #define perf_cpu_map__for_each_cpu(cpu, idx, cpus)         \
> > >     for ((idx) = 0, (cpu) = perf_cpu_map__cpu(cpus, idx);   \
> > > diff --git a/tools/perf/tests/cpumap.c b/tools/perf/tests/cpumap.c
> > > index 83805690c209..7730fc2ab40b 100644
> > > --- a/tools/perf/tests/cpumap.c
> > > +++ b/tools/perf/tests/cpumap.c
> > > @@ -211,11 +211,48 @@ static int test__cpu_map_intersect(struct test_suite *test __maybe_unused,
> > >     return ret;
> > >  }
> > >
> > > +static int test__cpu_map_equal(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
> > > +{
> > > +   struct perf_cpu_map *any = perf_cpu_map__dummy_new();
> > > +   struct perf_cpu_map *one = perf_cpu_map__new("1");
> > > +   struct perf_cpu_map *two = perf_cpu_map__new("2");
> > > +   struct perf_cpu_map *empty = perf_cpu_map__intersect(one, two);
> > > +   struct perf_cpu_map *pair = perf_cpu_map__new("1-2");
> > > +   struct perf_cpu_map *tmp;
> > > +   struct perf_cpu_map *maps[] = {empty, any, one, two, pair};
> > > +
> > > +   for (size_t i = 0; i < ARRAY_SIZE(maps); i++) {
> > > +           /* Maps equal themself. */
> > > +           TEST_ASSERT_VAL("equal", perf_cpu_map__equal(maps[i], maps[i]));
> > > +           for (size_t j = 0; j < ARRAY_SIZE(maps); j++) {
> > > +                   /* Maps dont't equal each other. */
> > > +                   if (i == j)
> > > +                           continue;
> > > +                   TEST_ASSERT_VAL("not equal", !perf_cpu_map__equal(maps[i], maps[j]));
> > > +           }
> > > +   }
> > > +
> > > +   /* Maps equal made maps. */
> > > +   tmp = perf_cpu_map__merge(perf_cpu_map__get(one), two);
> > > +   TEST_ASSERT_VAL("pair", perf_cpu_map__equal(pair, tmp));
> > > +   perf_cpu_map__put(tmp);
> > > +
> > > +   tmp = perf_cpu_map__intersect(pair, one);
> > > +   TEST_ASSERT_VAL("one", perf_cpu_map__equal(one, tmp));
> > > +   perf_cpu_map__put(tmp);
> > > +
> > > +   for (size_t i = 0; i < ARRAY_SIZE(maps); i++)
> > > +           perf_cpu_map__put(maps[i]);
> > > +
> > > +   return TEST_OK;
> > > +}
> > > +
> > >  static struct test_case tests__cpu_map[] = {
> > >     TEST_CASE("Synthesize cpu map", cpu_map_synthesize),
> > >     TEST_CASE("Print cpu map", cpu_map_print),
> > >     TEST_CASE("Merge cpu map", cpu_map_merge),
> > >     TEST_CASE("Intersect cpu map", cpu_map_intersect),
> > > +   TEST_CASE("Equal cpu map", cpu_map_equal),
> > >     {       .name = NULL, }
> > >  };
> > >
> > > --
> > > 2.41.0.rc0.172.g3f132b7071-goog
> > >
> >
> > --
> >
> > - Arnaldo
>
> --
>
> - Arnaldo
diff mbox series

Patch

diff --git a/tools/lib/perf/cpumap.c b/tools/lib/perf/cpumap.c
index d4f3a1a12522..48595a3ad69c 100644
--- a/tools/lib/perf/cpumap.c
+++ b/tools/lib/perf/cpumap.c
@@ -321,6 +321,27 @@  bool perf_cpu_map__has(const struct perf_cpu_map *cpus, struct perf_cpu cpu)
 	return perf_cpu_map__idx(cpus, cpu) != -1;
 }
 
+bool perf_cpu_map__equal(const struct perf_cpu_map *lhs, const struct perf_cpu_map *rhs)
+{
+	int nr;
+
+	if (lhs == rhs)
+		return true;
+
+	if (!lhs || !rhs)
+		return false;
+
+	nr = perf_cpu_map__nr(lhs);
+	if (nr != perf_cpu_map__nr(rhs))
+		return false;
+
+	for (int idx = 0; idx < nr; idx++) {
+		if (RC_CHK_ACCESS(lhs)->map[idx].cpu != RC_CHK_ACCESS(rhs)->map[idx].cpu)
+			return false;
+	}
+	return true;
+}
+
 struct perf_cpu perf_cpu_map__max(const struct perf_cpu_map *map)
 {
 	struct perf_cpu result = {
diff --git a/tools/lib/perf/include/perf/cpumap.h b/tools/lib/perf/include/perf/cpumap.h
index 0466c4216fbb..d0ae9552f8e2 100644
--- a/tools/lib/perf/include/perf/cpumap.h
+++ b/tools/lib/perf/include/perf/cpumap.h
@@ -28,6 +28,8 @@  LIBPERF_API int perf_cpu_map__nr(const struct perf_cpu_map *cpus);
 LIBPERF_API bool perf_cpu_map__empty(const struct perf_cpu_map *map);
 LIBPERF_API struct perf_cpu perf_cpu_map__max(const struct perf_cpu_map *map);
 LIBPERF_API bool perf_cpu_map__has(const struct perf_cpu_map *map, struct perf_cpu cpu);
+LIBPERF_API bool perf_cpu_map__equal(const struct perf_cpu_map *lhs,
+				     const struct perf_cpu_map *rhs);
 
 #define perf_cpu_map__for_each_cpu(cpu, idx, cpus)		\
 	for ((idx) = 0, (cpu) = perf_cpu_map__cpu(cpus, idx);	\
diff --git a/tools/perf/tests/cpumap.c b/tools/perf/tests/cpumap.c
index 83805690c209..7730fc2ab40b 100644
--- a/tools/perf/tests/cpumap.c
+++ b/tools/perf/tests/cpumap.c
@@ -211,11 +211,48 @@  static int test__cpu_map_intersect(struct test_suite *test __maybe_unused,
 	return ret;
 }
 
+static int test__cpu_map_equal(struct test_suite *test __maybe_unused, int subtest __maybe_unused)
+{
+	struct perf_cpu_map *any = perf_cpu_map__dummy_new();
+	struct perf_cpu_map *one = perf_cpu_map__new("1");
+	struct perf_cpu_map *two = perf_cpu_map__new("2");
+	struct perf_cpu_map *empty = perf_cpu_map__intersect(one, two);
+	struct perf_cpu_map *pair = perf_cpu_map__new("1-2");
+	struct perf_cpu_map *tmp;
+	struct perf_cpu_map *maps[] = {empty, any, one, two, pair};
+
+	for (size_t i = 0; i < ARRAY_SIZE(maps); i++) {
+		/* Maps equal themself. */
+		TEST_ASSERT_VAL("equal", perf_cpu_map__equal(maps[i], maps[i]));
+		for (size_t j = 0; j < ARRAY_SIZE(maps); j++) {
+			/* Maps dont't equal each other. */
+			if (i == j)
+				continue;
+			TEST_ASSERT_VAL("not equal", !perf_cpu_map__equal(maps[i], maps[j]));
+		}
+	}
+
+	/* Maps equal made maps. */
+	tmp = perf_cpu_map__merge(perf_cpu_map__get(one), two);
+	TEST_ASSERT_VAL("pair", perf_cpu_map__equal(pair, tmp));
+	perf_cpu_map__put(tmp);
+
+	tmp = perf_cpu_map__intersect(pair, one);
+	TEST_ASSERT_VAL("one", perf_cpu_map__equal(one, tmp));
+	perf_cpu_map__put(tmp);
+
+	for (size_t i = 0; i < ARRAY_SIZE(maps); i++)
+		perf_cpu_map__put(maps[i]);
+
+	return TEST_OK;
+}
+
 static struct test_case tests__cpu_map[] = {
 	TEST_CASE("Synthesize cpu map", cpu_map_synthesize),
 	TEST_CASE("Print cpu map", cpu_map_print),
 	TEST_CASE("Merge cpu map", cpu_map_merge),
 	TEST_CASE("Intersect cpu map", cpu_map_intersect),
+	TEST_CASE("Equal cpu map", cpu_map_equal),
 	{	.name = NULL, }
 };