bpf_cookie and find_vma are flaky in nested VMs, which is used by some CI
systems. It turns out these failures are caused by unreliable perf event
in nested VM. Fix these by:
1. Use PERF_COUNT_SW_CPU_CLOCK in find_vma;
2. Increase sample_freq in bpf_cookie.
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240604070700.3032142-1-song@kernel.org
Remove unneeded spleep and increase length of dummy CPU
intensive computation to guarantee test process execution.
Also, complete aforemention computation as soon as
test success criteria is met
Signed-off-by: Mykola Lysenko <mykolal@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220308200449.1757478-4-mykolal@fb.com
Linux kernel may automatically reduce kernel.perf_event_max_sample_rate
value when running tests in parallel on slow systems. Linux kernel checks
against this limit when opening perf event with freq=1 parameter set.
The lower bound is 1000. This patch reduces sample_freq value to 1000
in all BPF tests that use sample_freq to ensure they always can open
perf event.
Signed-off-by: Mykola Lysenko <mykolal@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220308200449.1757478-2-mykolal@fb.com
Add tests for bpf_find_vma in perf_event program and kprobe program. The
perf_event program is triggered from NMI context, so the second call of
bpf_find_vma() will return -EBUSY (irq_work busy). The kprobe program,
on the other hand, does not have this constraint.
Also add tests for illegal writes to task or vma from the callback
function. The verifier should reject both cases.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20211105232330.1936330-3-songliubraving@fb.com
