Re: [PATCH 14/14] perf tests: Add test for closing dso objects on EMFILE error

[Namhyung Kim <namhyung@gmail.com>]

On Thu, 15 May 2014 19:23:35 +0200, Jiri Olsa wrote:
> Testing that perf properly closes opened dso objects
> and tries to reopen in case we run out of allowed file
> descriptors for dso data.
>
> Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
> Cc: David Ahern <dsahern@gmail.com>
> Cc: Frederic Weisbecker <fweisbec@gmail.com>
> Cc: Ingo Molnar <mingo@kernel.org>
> Cc: Jean Pihet <jean.pihet@linaro.org>
> Cc: Namhyung Kim <namhyung@kernel.org>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> ---
>  tools/perf/tests/builtin-test.c |  4 +++
>  tools/perf/tests/dso-data.c     | 70 +++++++++++++++++++++++++++++++++++++++++
>  tools/perf/tests/tests.h        |  1 +
>  3 files changed, 75 insertions(+)
>
> diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
> index c4d581a..a489cda 100644
> --- a/tools/perf/tests/builtin-test.c
> +++ b/tools/perf/tests/builtin-test.c
> @@ -60,6 +60,10 @@ static struct test {
>  		.func = test__dso_data_cache,
>  	},
>  	{
> +		.desc = "Test dso data reopen",
> +		.func = test__dso_data_reopen,
> +	},
> +	{
>  		.desc = "roundtrip evsel->name check",
>  		.func = test__perf_evsel__roundtrip_name_test,
>  	},
> diff --git a/tools/perf/tests/dso-data.c b/tools/perf/tests/dso-data.c
> index 84ab939..ecc8acd 100644
> --- a/tools/perf/tests/dso-data.c
> +++ b/tools/perf/tests/dso-data.c
> @@ -328,3 +328,73 @@ int test__dso_data_cache(void)
>  	TEST_ASSERT_VAL("failed leadking files", nr == open_files_cnt());
>  	return 0;
>  }
> +
> +int test__dso_data_reopen(void)
> +{
> +	struct machine machine;
> +	long nr = open_files_cnt();
> +#define BUFSIZE 10

Looks like a copy-n-paste error.. :)


> +	int fd, fd_extra;
> +
> +	memset(&machine, 0, sizeof(machine));
> +
> +	/*
> +	 * Test scenario:
> +	 * - create 3 dso objects
> +	 * - set process file descriptor limit to current
> +	 *   files count + 3
> +	 * - test that the first dso gets closed when we
> +	 *   reach the files count limit
> +	 */
> +
> +	/* Make sure we are able to open 3 fds anyway */
> +	TEST_ASSERT_VAL("failed to set file limit",
> +			!set_fd_limit((nr + 3)));
> +
> +	TEST_ASSERT_VAL("failed to create dsos\n", !dsos__create(TEST_FILE_SIZE));
> +
> +	/* open dso_0 */
> +	fd = dso__data_fd(dso_0, &machine);
> +	TEST_ASSERT_VAL("failed to get fd", fd > 0);
> +
> +	/* open dso_1 */
> +	fd = dso__data_fd(dso_1, &machine);
> +	TEST_ASSERT_VAL("failed to get fd", fd > 0);
> +
> +	/*
> +	 * open extra file descriptor and we just
> +	 * reached the files count limit
> +	 */
> +	fd_extra = open("/dev/null", O_RDONLY);
> +	TEST_ASSERT_VAL("failed to open extra fd", fd_extra > 0);
> +
> +	/* open dso_2 */
> +	fd = dso__data_fd(dso_2, &machine);
> +	TEST_ASSERT_VAL("failed to get fd", fd > 0);
> +
> +	/*
> +	 * dso_0 should get closed, because we reached
> +	 * the file descriptor limit
> +	 */
> +	TEST_ASSERT_VAL("failed to close dso_0", dso_0->data.fd == -1);
> +
> +	/* open dso_0 */
> +	fd = dso__data_fd(dso_0, &machine);
> +	TEST_ASSERT_VAL("failed to get fd", fd > 0);
> +
> +	/*
> +	 * dso_1 should get closed, because we reached
> +	 * the file descriptor limit
> +	 */
> +	TEST_ASSERT_VAL("failed to close dso_0", dso_1->data.fd == -1);

s/dso_0/dso_1/

Btw, I don't see a big difference between this and previous testcase.
Any chance to merge them into one?

Thanks,
Namhyung

> +
> +	/* cleanup everything */
> +	close(fd_extra);
> +	dsos__delete();
> +
> +	pr_debug("nr start %ld, nr stop %ld\n", nr, open_files_cnt());
> +
> +	/* Make sure we did not leak any file descriptor. */
> +	TEST_ASSERT_VAL("failed leadking files", nr == open_files_cnt());
> +	return 0;
> +}
> diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
> index 61e12b6..3247ca1 100644
> --- a/tools/perf/tests/tests.h
> +++ b/tools/perf/tests/tests.h
> @@ -29,6 +29,7 @@ int test__pmu(void);
>  int test__attr(void);
>  int test__dso_data(void);
>  int test__dso_data_cache(void);
> +int test__dso_data_reopen(void);
>  int test__parse_events(void);
>  int test__hists_link(void);
>  int test__python_use(void);