Re: [PATCH bpf-next v2] selftests/bpf: Add bpf_proactive_reclaim test

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] selftests/bpf: memcg_proactive_reclaim test fails instead of skipping when regular fs is missing
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commit 8a730887084ae177532f166fce0611c868fe9578
Author: Hui Zhu <zhuhui@kylinos.cn>

selftests/bpf: Add bpf_proactive_reclaim test

This commit adds a selftest for the bpf_proactive_reclaim() kfunc. It charges
page cache to a cgroup and issues a bounded reclaim pass using the BPF helper,
verifying that the result is capped correctly.

> diff --git a/tools/testing/selftests/bpf/prog_tests/memcg_proactive_reclaim.c b/tools/testing/selftests/bpf/prog_tests/memcg_proactive_reclaim.c
> new file mode 100644
> index 0000000000000..d642658a21981
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/prog_tests/memcg_proactive_reclaim.c
[ ... ]
> +static const char *workload_dir(void)
> +{
> +	static const char * const dirs[] = { "/tmp", "." };
> +	struct statfs st;
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(dirs); i++)
> +		if (!statfs(dirs[i], &st) && st.f_type != TMPFS_MAGIC &&
> +		    st.f_type != RAMFS_MAGIC)
> +			return dirs[i];
> +
> +	return NULL;
> +}
> +
> +void test_memcg_proactive_reclaim(void)
> +{
[ ... ]
> +	dir = workload_dir();
> +	if (!ASSERT_OK_PTR(dir, "workload dir on a regular filesystem"))
> +		return;

[Severity: Medium]
Will this cause the test suite to incorrectly report a failure rather than a
skip when a regular filesystem is missing?

If workload_dir() returns NULL when both /tmp and . are tmpfs or ramfs (which
is common in CI or initramfs environments), using ASSERT_OK_PTR(dir) here
will fail the test suite explicitly. Should this skip the test instead?

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Sashiko AI review · https://sashiko.dev/#/patchset/20260928063724.24008-1-hui.zhu@linux.dev?part=1