| Message ID | 159842985651.1050885.2154399297503372406.stgit@firesoul |
|---|---|
| State | Accepted |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | [bpf] selftests/bpf: Fix massive output from test_maps | expand |
On Wed, 26 Aug 2020 10:17:36 +0200 Jesper Dangaard Brouer <brouer@redhat.com> wrote: > When stdout output from the selftests tool 'test_maps' gets redirected > into e.g file or pipe, then the output lines increase a lot (from 21 > to 33949 lines). This is caused by the printf that happens before the > fork() call, and there are user-space buffered printf data that seems > to be duplicated into the forked process. > > To fix this fflush() stdout before the fork loop in __run_parallel(). > > Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Fixes: 1a97cf1fe503 ("selftests/bpf: speedup test_maps") I forgot to add the fixes line to the patch, I hope patchwork[1] will pick it up for maintainers. [1] http://patchwork.ozlabs.org/project/netdev/patch/159842985651.1050885.2154399297503372406.stgit@firesoul/
On 8/26/20 10:29 AM, Jesper Dangaard Brouer wrote: > On Wed, 26 Aug 2020 10:17:36 +0200 > Jesper Dangaard Brouer <brouer@redhat.com> wrote: > >> When stdout output from the selftests tool 'test_maps' gets redirected >> into e.g file or pipe, then the output lines increase a lot (from 21 >> to 33949 lines). This is caused by the printf that happens before the >> fork() call, and there are user-space buffered printf data that seems >> to be duplicated into the forked process. >> >> To fix this fflush() stdout before the fork loop in __run_parallel(). >> >> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> > > Fixes: 1a97cf1fe503 ("selftests/bpf: speedup test_maps") > > I forgot to add the fixes line to the patch, I hope patchwork[1] will > pick it up for maintainers. It won't but I've just added it manually. Applied, thanks! > [1] http://patchwork.ozlabs.org/project/netdev/patch/159842985651.1050885.2154399297503372406.stgit@firesoul/ >
diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c index 754cf611723e..0d92ebcb335d 100644 --- a/tools/testing/selftests/bpf/test_maps.c +++ b/tools/testing/selftests/bpf/test_maps.c @@ -1274,6 +1274,8 @@ static void __run_parallel(unsigned int tasks, pid_t pid[tasks]; int i; + fflush(stdout); + for (i = 0; i < tasks; i++) { pid[i] = fork(); if (pid[i] == 0) {
When stdout output from the selftests tool 'test_maps' gets redirected into e.g file or pipe, then the output lines increase a lot (from 21 to 33949 lines). This is caused by the printf that happens before the fork() call, and there are user-space buffered printf data that seems to be duplicated into the forked process. To fix this fflush() stdout before the fork loop in __run_parallel(). Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> --- tools/testing/selftests/bpf/test_maps.c | 2 ++ 1 file changed, 2 insertions(+)