From a8fce027e17b0a99a8f9732f271ed505aa7a2940 Mon Sep 17 00:00:00 2001 From: Hui Zhu Date: Tue, 3 Mar 2026 13:53:08 +0800 Subject: [PATCH 1/2] selftests/bpf: Remove kmem subtest from cgroup_iter_memcg When cgroup.memory=nokmem is set in the kernel command line, kmem accounting is disabled. This causes the test_kmem subtest in cgroup_iter_memcg to fail because it expects non-zero kmem values. Remove the kmem subtest altogether since the remaining subtests (shmem, file, pgfault) already provide sufficient coverage for the cgroup iter memcg functionality. Reviewed-by: JP Kobryn Signed-off-by: Hui Zhu Link: https://lore.kernel.org/r/35fa32a019361ec26265c8a789ee31e448d4dbda.1772505399.git.zhuhui@kylinos.cn Signed-off-by: Alexei Starovoitov --- .../testing/selftests/bpf/cgroup_iter_memcg.h | 2 -- .../bpf/prog_tests/cgroup_iter_memcg.c | 28 ------------------- .../selftests/bpf/progs/cgroup_iter_memcg.c | 1 - 3 files changed, 31 deletions(-) diff --git a/tools/testing/selftests/bpf/cgroup_iter_memcg.h b/tools/testing/selftests/bpf/cgroup_iter_memcg.h index 3f59b127943b..ff20ec537164 100644 --- a/tools/testing/selftests/bpf/cgroup_iter_memcg.h +++ b/tools/testing/selftests/bpf/cgroup_iter_memcg.h @@ -9,8 +9,6 @@ struct memcg_query { unsigned long nr_shmem; unsigned long nr_file_pages; unsigned long nr_file_mapped; - /* some memcg_stat_item */ - unsigned long memcg_kmem; /* some vm_event_item */ unsigned long pgfault; }; diff --git a/tools/testing/selftests/bpf/prog_tests/cgroup_iter_memcg.c b/tools/testing/selftests/bpf/prog_tests/cgroup_iter_memcg.c index a5afd16705f0..88fc3e83d2b7 100644 --- a/tools/testing/selftests/bpf/prog_tests/cgroup_iter_memcg.c +++ b/tools/testing/selftests/bpf/prog_tests/cgroup_iter_memcg.c @@ -126,32 +126,6 @@ static void test_shmem(struct bpf_link *link, struct memcg_query *memcg_query) shm_unlink("/tmp_shmem"); } -#define NR_PIPES 64 -static void test_kmem(struct bpf_link *link, struct memcg_query *memcg_query) -{ - int fds[NR_PIPES][2], i; - - /* - * Increase kmem value by creating pipes which will allocate some - * kernel buffers. - */ - for (i = 0; i < NR_PIPES; i++) { - if (!ASSERT_OK(pipe(fds[i]), "pipe")) - goto cleanup; - } - - if (!ASSERT_OK(read_stats(link), "read stats")) - goto cleanup; - - ASSERT_GT(memcg_query->memcg_kmem, 0, "kmem value"); - -cleanup: - for (i = i - 1; i >= 0; i--) { - close(fds[i][0]); - close(fds[i][1]); - } -} - static void test_pgfault(struct bpf_link *link, struct memcg_query *memcg_query) { void *map; @@ -209,8 +183,6 @@ void test_cgroup_iter_memcg(void) test_shmem(link, &skel->data_query->memcg_query); if (test__start_subtest("cgroup_iter_memcg__file")) test_file(link, &skel->data_query->memcg_query); - if (test__start_subtest("cgroup_iter_memcg__kmem")) - test_kmem(link, &skel->data_query->memcg_query); if (test__start_subtest("cgroup_iter_memcg__pgfault")) test_pgfault(link, &skel->data_query->memcg_query); diff --git a/tools/testing/selftests/bpf/progs/cgroup_iter_memcg.c b/tools/testing/selftests/bpf/progs/cgroup_iter_memcg.c index 59fb70a3cc50..12f79a44133e 100644 --- a/tools/testing/selftests/bpf/progs/cgroup_iter_memcg.c +++ b/tools/testing/selftests/bpf/progs/cgroup_iter_memcg.c @@ -30,7 +30,6 @@ int cgroup_memcg_query(struct bpf_iter__cgroup *ctx) memcg_query.nr_shmem = bpf_mem_cgroup_page_state(memcg, NR_SHMEM); memcg_query.nr_file_pages = bpf_mem_cgroup_page_state(memcg, NR_FILE_PAGES); memcg_query.nr_file_mapped = bpf_mem_cgroup_page_state(memcg, NR_FILE_MAPPED); - memcg_query.memcg_kmem = bpf_mem_cgroup_page_state(memcg, MEMCG_KMEM); memcg_query.pgfault = bpf_mem_cgroup_vm_events(memcg, PGFAULT); bpf_put_mem_cgroup(memcg); From da99028c21137ac13925836d3819c2977694d173 Mon Sep 17 00:00:00 2001 From: Hui Zhu Date: Tue, 3 Mar 2026 13:53:09 +0800 Subject: [PATCH 2/2] selftests/bpf: Use bpf_core_enum_value for stats in cgroup_iter_memcg Replace hardcoded enum values with bpf_core_enum_value() calls in cgroup_iter_memcg test to improve portability across different kernel versions. The change adds runtime enum value resolution for: - node_stat_item: NR_ANON_MAPPED, NR_SHMEM, NR_FILE_PAGES, NR_FILE_MAPPED - vm_event_item: PGFAULT This ensures the BPF program can adapt to enum value changes between kernel versions. Reviewed-by: Emil Tsalapatis Reviewed-by: JP Kobryn Signed-off-by: Hui Zhu Link: https://lore.kernel.org/r/ca6eb1a1a4fd7a17ffe995acf52c9a4ceb7bac13.1772505399.git.zhuhui@kylinos.cn Signed-off-by: Alexei Starovoitov --- .../selftests/bpf/progs/cgroup_iter_memcg.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/tools/testing/selftests/bpf/progs/cgroup_iter_memcg.c b/tools/testing/selftests/bpf/progs/cgroup_iter_memcg.c index 12f79a44133e..06a385c9d85b 100644 --- a/tools/testing/selftests/bpf/progs/cgroup_iter_memcg.c +++ b/tools/testing/selftests/bpf/progs/cgroup_iter_memcg.c @@ -26,11 +26,18 @@ int cgroup_memcg_query(struct bpf_iter__cgroup *ctx) bpf_mem_cgroup_flush_stats(memcg); - memcg_query.nr_anon_mapped = bpf_mem_cgroup_page_state(memcg, NR_ANON_MAPPED); - memcg_query.nr_shmem = bpf_mem_cgroup_page_state(memcg, NR_SHMEM); - memcg_query.nr_file_pages = bpf_mem_cgroup_page_state(memcg, NR_FILE_PAGES); - memcg_query.nr_file_mapped = bpf_mem_cgroup_page_state(memcg, NR_FILE_MAPPED); - memcg_query.pgfault = bpf_mem_cgroup_vm_events(memcg, PGFAULT); + memcg_query.nr_anon_mapped = bpf_mem_cgroup_page_state( + memcg, + bpf_core_enum_value(enum node_stat_item, NR_ANON_MAPPED)); + memcg_query.nr_shmem = bpf_mem_cgroup_page_state( + memcg, bpf_core_enum_value(enum node_stat_item, NR_SHMEM)); + memcg_query.nr_file_pages = bpf_mem_cgroup_page_state( + memcg, bpf_core_enum_value(enum node_stat_item, NR_FILE_PAGES)); + memcg_query.nr_file_mapped = bpf_mem_cgroup_page_state( + memcg, + bpf_core_enum_value(enum node_stat_item, NR_FILE_MAPPED)); + memcg_query.pgfault = bpf_mem_cgroup_vm_events( + memcg, bpf_core_enum_value(enum vm_event_item, PGFAULT)); bpf_put_mem_cgroup(memcg);