linux.git/tools/testing/selftests/bpf/test_maps.c, branch v5.14

selftests/bpf: Turn on libbpf 1.0 mode and fix all IS_ERR checks

2021-05-26T00:32:35+00:00

Turn ony libbpf 1.0 mode. Fix all the explicit IS_ERR checks that now will be
broken because libbpf returns NULL on error (and sets errno). Fix
ASSERT_OK_PTR and ASSERT_ERR_PTR to work for both old mode and new modes and
use them throughout selftests. This is trivial to do by using
libbpf_get_error() API that all libbpf users are supposed to use, instead of
IS_ERR checks.

A bunch of checks also did explicit -1 comparison for various fd-returning
APIs. Such checks are replaced with >= 0 or < 0 cases.

There were also few misuses of bpf_object__find_map_by_name() in test_maps.
Those are fixed in this patch as well.

Signed-off-by: Andrii Nakryiko 
Signed-off-by: Alexei Starovoitov 
Acked-by: John Fastabend 
Acked-by: Toke Høiland-Jørgensen 
Link: https://lore.kernel.org/bpf/20210525035935.1461796-3-andrii@kernel.org

selftests/bpf: Add bpf_lookup_and_delete_elem tests

2021-05-24T20:30:52+00:00

Add bpf selftests and extend existing ones for a new function
bpf_lookup_and_delete_elem() for (percpu) hash and (percpu) LRU hash map
types.
In test_lru_map and test_maps we add an element, lookup_and_delete it,
then check whether it's deleted.
The newly added lookup_and_delete prog tests practically do the same
thing but additionally use a BPF program to change the value of the
element for LRU maps.

Signed-off-by: Denis Salopek 
Signed-off-by: Andrii Nakryiko 
Acked-by: Yonghong Song 
Link: https://lore.kernel.org/bpf/d30d3e0060c1f750e133579623cf1c60ff58f3d9.1620763117.git.denis.salopek@sartura.hr

selftests/bpf: Work-around EBUSY errors from hashmap update/delete

2020-12-24T00:35:46+00:00

20b6cc34ea74 ("bpf: Avoid hashtab deadlock with map_locked") introduced
a possibility of getting EBUSY error on lock contention, which seems to happen
very deterministically in test_maps when running 1024 threads on low-CPU
machine. In libbpf CI case, it's a 2 CPU VM and it's hitting this 100% of the
time. Work around by retrying on EBUSY (and EAGAIN, while we are at it) after
a small sleep. sched_yield() is too agressive and fails even after 20 retries,
so I went with usleep(1) for backoff.

Also log actual error returned to make it easier to see what's going on.

Fixes: 20b6cc34ea74 ("bpf: Avoid hashtab deadlock with map_locked")
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Acked-by: Song Liu 
Link: https://lore.kernel.org/bpf/20201223200652.3417075-1-andrii@kernel.org

bpf: Lift hashtab key_size limit

2020-11-06T04:04:46+00:00

Currently key_size of hashtab is limited to MAX_BPF_STACK.
As the key of hashtab can also be a value from a per cpu map it can be
larger than MAX_BPF_STACK.

The use-case for this patch originates to implement allow/disallow
lists for files and file paths. The maximum length of file paths is
defined by PATH_MAX with 4096 chars including nul.
This limit exceeds MAX_BPF_STACK.

Changelog:

v5:
 - Fix cast overflow

v4:
 - Utilize BPF skeleton in tests
 - Rebase

v3:
 - Rebase

v2:
 - Add a test for bpf side

Signed-off-by: Florian Lehner 
Signed-off-by: Alexei Starovoitov 
Acked-by: John Fastabend 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20201029201442.596690-1-dev@der-flo.net

selftests/bpf: Fix massive output from test_maps

2020-08-28T11:58:19+00:00

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().

Fixes: 1a97cf1fe503 ("selftests/bpf: speedup test_maps")
Signed-off-by: Jesper Dangaard Brouer 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/159842985651.1050885.2154399297503372406.stgit@firesoul

selftests: bpf: Fix detach from sockmap tests

2020-07-09T21:41:37+00:00

Fix sockmap tests which rely on old bpf_prog_dispatch behaviour.
In the first case, the tests check that detaching without giving
a program succeeds. Since these are not the desired semantics,
invert the condition. In the second case, the clean up code doesn't
supply the necessary program fds.

Fixes: bb0de3131f4c ("bpf: sockmap: Require attach_bpf_fd when detaching a program")
Reported-by: Martin KaFai Lau 
Signed-off-by: Lorenz Bauer 
Signed-off-by: Daniel Borkmann 
Reviewed-by: Jakub Sitnicki 
Link: https://lore.kernel.org/bpf/20200709115151.75829-1-lmb@cloudflare.com

selftests/bpf: Add tests for write-only stacks/queues

2020-06-01T21:38:22+00:00

For write-only stacks and queues bpf_map_update_elem should be allowed, but
bpf_map_lookup_elem and bpf_map_lookup_and_delete_elem should fail with EPERM.

Signed-off-by: Anton Protopopov 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20200527185700.14658-6-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov

selftests/bpf: Cleanup comments in test_maps

2020-06-01T21:38:21+00:00

Make comments inside the test_map_rdonly and test_map_wronly tests
consistent with logic.

Signed-off-by: Anton Protopopov 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20200527185700.14658-4-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov

selftests/bpf: Cleanup some file descriptors in test_maps

2020-06-01T21:38:21+00:00

The test_map_rdonly and test_map_wronly tests should close file descriptors
which they open.

Signed-off-by: Anton Protopopov 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20200527185700.14658-3-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov

selftests/bpf: Fix a typo in test_maps

2020-06-01T21:38:21+00:00

Trivial fix to a typo in the test_map_wronly test: "read" -> "write"

Signed-off-by: Anton Protopopov 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20200527185700.14658-2-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov