On Fri, Mar 13, 2020 at 06:39:32PM -0700, Andrii Nakryiko wrote:
> Some tests and sub-tests are setting "custom" thread/process affinity and
> don't reset it back. Instead of requiring each test to undo all this, ensure
> that thread affinity is restored by test_progs test runner itself.
>
> Signed-off-by: Andrii Nakryiko <andriin@xxxxxx>
> ---
> tools/testing/selftests/bpf/test_progs.c | 42 +++++++++++++++++++++++-
> tools/testing/selftests/bpf/test_progs.h | 1 +
> 2 files changed, 42 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
> index c8cb407482c6..b521e0a512b6 100644
> --- a/tools/testing/selftests/bpf/test_progs.c
> +++ b/tools/testing/selftests/bpf/test_progs.c
> @@ -1,12 +1,15 @@
> // SPDX-License-Identifier: GPL-2.0-only
> /* Copyright (c) 2017 Facebook
> */
> +#define _GNU_SOURCE
> #include "test_progs.h"
> #include "cgroup_helpers.h"
> #include "bpf_rlimit.h"
> #include <argp.h>
> -#include <string.h>
> +#include <pthread.h>
> +#include <sched.h>
> #include <signal.h>
> +#include <string.h>
> #include <execinfo.h> /* backtrace */
>
> /* defined in test_progs.h */
> @@ -90,6 +93,34 @@ static void skip_account(void)
> }
> }
>
> +static void stdio_restore(void);
> +
> +/* A bunch of tests set custom affinity per-thread and/or per-process. Reset
> + * it after each test/sub-test.
> + */
> +static void reset_affinity() {
> +
> + cpu_set_t cpuset;
> + int i, err;
> +
> + CPU_ZERO(&cpuset);
> + for (i = 0; i < env.nr_cpus; i++)
> + CPU_SET(i, &cpuset);
In case the user may run "taskset somemask test_progs",
is it better to store the inital_cpuset at the beginning
of main and then restore to inital_cpuset after each run?
> +
> + err = sched_setaffinity(0, sizeof(cpuset), &cpuset);
> + if (err < 0) {
> + stdio_restore();
> + fprintf(stderr, "Failed to reset process affinity: %d!\n", err);
> + exit(-1);
> + }
> + err = pthread_setaffinity_np(pthread_self(), sizeof(cpuset), &cpuset);
> + if (err < 0) {
> + stdio_restore();
> + fprintf(stderr, "Failed to reset thread affinity: %d!\n", err);
> + exit(-1);
> + }
> +}
