Commit Graph

5 Commits

Author SHA1 Message Date
Jiayuan Chen
fdec474c65
selftests/bpf: Report the real error from libarena parallel workers
Several CI runs failed in the libarena parallel tests with -4 (-EINTR) [1],
which says nothing about what actually went wrong.

Two workers can fail like this:

  worker 1: gives up, e.g. the rendezvous times out, sets test_abort and
            returns its own error (-ETIMEDOUT)
  worker 2: sees test_abort and returns -EINTR

-EINTR only means "someone else already gave up", so it carries no
information. Which of the two gets reported depends on the order
pthread_join() collects them, because

	err = err ?: (long)thread_ret;

keeps the first non-zero value and drops the rest. When the -EINTR worker
comes first, the error describing the actual failure is lost.

Skip -EINTR entirely: a worker only returns it once another worker has
already reported the real error, so report and log only the real errors.

It is still unclear whether the timeouts come from CI load or from a
problem in the test itself. Report the error accurately first, so the next
failure can be diagnosed.

[1]:
https://github.com/kernel-patches/bpf/actions/runs/29867905253/job/88764463566
https://github.com/kernel-patches/bpf/actions/runs/29878191901/job/88794845824

Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/bpf/20260723061347.398591-1-jiayuan.chen@linux.dev
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-28 02:51:34 +02:00
Jiayuan Chen
a14f9ba080
selftests/bpf: Run arena tests serially
Every arena reserves a 4GB kernel vmalloc region at creation, and on a
KASAN build that eagerly populates ~512MB of shadow memory per arena. When
several arena tests run in parallel their shadow adds up, exhausts the
memory of a small CI VM and trips the OOM killer during map creation.

Make the dedicated arena tests (arena_* and libarena*) serial so they no
longer pile up in the parallel phase. That alone brings the peak number of
live arenas back within the CI memory budget.

A few other tests such as verifier_arena*, stream and compute_live_registers
create an arena too, but they run inside shared RUN_TESTS()/RUN() suites, so
turning them serial would drag many unrelated subtests along with them.
Leave those as-is.

Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/bpf/20260717114117.350851-4-jiayuan.chen@linux.dev
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-19 17:56:09 +02:00
Emil Tsalapatis
14c2b770d1
selftests/bpf: libarena: Clean up allocation state before buddy tests
Summary: The buddy allocator requires the global BPF buddy allocator
to not be already initialized. However, the test currently merely resets
the allocator before the buddy tests instead of destroying it, and the
test worked because the buddy test happened to run first. Properly
destroy the allocator instead of resetting it.

Fixes: b1487dc1b1 ("selftests/bpf: Add selftests for libarena buddy allocator")
Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Acked-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Link: https://lore.kernel.org/bpf/20260706181730.21731-4-emil@etsalapatis.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
2026-07-07 18:09:01 +02:00
Emil Tsalapatis
42998f8192 selftests/bpf: libarena: parallel test harness and spmc parallel selftest
Add a parallel test for the SPMC Lev-Chase workstealing queue. The queue
is built to be wait-free even when there are multiple consumers, and
the parallel selftest provides a signal on whether the queue behaves
correctly when stress tested.

To support the test, this patch includes a test harness for parallel
selftests. The spmc selftest acts as an example of the naming and other
conventions expected by the harness.

Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/r/20260605222020.5231-4-emil@etsalapatis.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-06-05 20:32:21 -07:00
Emil Tsalapatis
b1487dc1b1 selftests/bpf: Add selftests for libarena buddy allocator
Introduce selftests for the buddy allocator with and without
ASAN. Add the libarena selftests both to the libarena test
runner and to test_progs, so that they are a) available when
libarena is pulled as a standalone library, and b) exercised
along with all other test programs in this directory.

ASAN for libarena requires LLVM 22. Add logic in the top-level
selftests Makefile to only compile the ASAN variant if the
compiler supports it, otherwise skip the test.

Signed-off-by: Emil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/r/20260426190338.4615-8-emil@etsalapatis.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2026-04-26 18:12:22 -07:00