Re: [PATCH 2/3] selftests/perf_events: Test modification of perf_event_attr::sig_data

Dmitry Vyukov
2022-02-01T07:33:41Z

On Mon, 31 Jan 2022 at 11:34, Marco Elver <elver@google.com> wrote:
>
> Test that PERF_EVENT_IOC_MODIFY_ATTRIBUTES correctly modifies
> perf_event_attr::sig_data as well.
>
> Signed-off-by: Marco Elver <elver@google.com>

Reviewed-by: Dmitry Vyukov <dvyukov@google.com>

> ---
> .../selftests/perf_events/sigtrap_threads.c | 17 +++++++++--------
> 1 file changed, 9 insertions(+), 8 deletions(-)
>
> diff --git a/tools/testing/selftests/perf_events/sigtrap_threads.c b/tools/testing/selftests/perf_events/sigtrap_threads.c
> index 8e83cf91513a..6d849dc2bee0 100644
> --- a/tools/testing/selftests/perf_events/sigtrap_threads.c
> +++ b/tools/testing/selftests/perf_events/sigtrap_threads.c
> @@ -44,9 +44,10 @@ static struct {
> } ctx;
>
> /* Unique value to check si_perf_data is correctly set from perf_event_attr::sig_data. */
> -#define TEST_SIG_DATA(addr) (~(unsigned long)(addr))
> +#define TEST_SIG_DATA(addr, id) (~(unsigned long)(addr) + id)
>
> -static struct perf_event_attr make_event_attr(bool enabled, volatile void *addr)
> +static struct perf_event_attr make_event_attr(bool enabled, volatile void *addr,
> + unsigned long id)
> {
> struct perf_event_attr attr = {
> .type = PERF_TYPE_BREAKPOINT,
> @@ -60,7 +61,7 @@ static struct perf_event_attr make_event_attr(bool enabled, volatile void *addr)
> .inherit_thread = 1, /* ... but only cloned with CLONE_THREAD. */
> .remove_on_exec = 1, /* Required by sigtrap. */
> .sigtrap = 1, /* Request synchronous SIGTRAP on event. */
> - .sig_data = TEST_SIG_DATA(addr),
> + .sig_data = TEST_SIG_DATA(addr, id),
> };
> return attr;
> }
> @@ -110,7 +111,7 @@ FIXTURE(sigtrap_threads)
>
> FIXTURE_SETUP(sigtrap_threads)
> {
> - struct perf_event_attr attr = make_event_attr(false, &ctx.iterate_on);
> + struct perf_event_attr attr = make_event_attr(false, &ctx.iterate_on, 0);
> struct sigaction action = {};
> int i;
>
> @@ -165,7 +166,7 @@ TEST_F(sigtrap_threads, enable_event)
> EXPECT_EQ(ctx.tids_want_signal, 0);
> EXPECT_EQ(ctx.first_siginfo.si_addr, &ctx.iterate_on);
> EXPECT_EQ(ctx.first_siginfo.si_perf_type, PERF_TYPE_BREAKPOINT);
> - EXPECT_EQ(ctx.first_siginfo.si_perf_data, TEST_SIG_DATA(&ctx.iterate_on));
> + EXPECT_EQ(ctx.first_siginfo.si_perf_data, TEST_SIG_DATA(&ctx.iterate_on, 0));
>
> /* Check enabled for parent. */
> ctx.iterate_on = 0;
> @@ -175,7 +176,7 @@ TEST_F(sigtrap_threads, enable_event)
> /* Test that modification propagates to all inherited events. */
> TEST_F(sigtrap_threads, modify_and_enable_event)
> {
> - struct perf_event_attr new_attr = make_event_attr(true, &ctx.iterate_on);
> + struct perf_event_attr new_attr = make_event_attr(true, &ctx.iterate_on, 42);
>
> EXPECT_EQ(ioctl(self->fd, PERF_EVENT_IOC_MODIFY_ATTRIBUTES, &new_attr), 0);
> run_test_threads(_metadata, self);
> @@ -184,7 +185,7 @@ TEST_F(sigtrap_threads, modify_and_enable_event)
> EXPECT_EQ(ctx.tids_want_signal, 0);
> EXPECT_EQ(ctx.first_siginfo.si_addr, &ctx.iterate_on);
> EXPECT_EQ(ctx.first_siginfo.si_perf_type, PERF_TYPE_BREAKPOINT);
> - EXPECT_EQ(ctx.first_siginfo.si_perf_data, TEST_SIG_DATA(&ctx.iterate_on));
> + EXPECT_EQ(ctx.first_siginfo.si_perf_data, TEST_SIG_DATA(&ctx.iterate_on, 42));
>
> /* Check enabled for parent. */
> ctx.iterate_on = 0;
> @@ -204,7 +205,7 @@ TEST_F(sigtrap_threads, signal_stress)
> EXPECT_EQ(ctx.tids_want_signal, 0);
> EXPECT_EQ(ctx.first_siginfo.si_addr, &ctx.iterate_on);
> EXPECT_EQ(ctx.first_siginfo.si_perf_type, PERF_TYPE_BREAKPOINT);
> - EXPECT_EQ(ctx.first_siginfo.si_perf_data, TEST_SIG_DATA(&ctx.iterate_on));
> + EXPECT_EQ(ctx.first_siginfo.si_perf_data, TEST_SIG_DATA(&ctx.iterate_on, 0));
> }
>
> TEST_HARNESS_MAIN
> --
> 2.35.0.rc2.247.g8bbb082509-goog
>