linux.git/tools/testing/selftests/bpf/progs/test_global_percpu_data.c, branch master

selftests/bpf: Improve readability in iter test for percpu data

2026-08-14T20:33:37+00:00

The original 'offsetof()' + offset is equal to the new 'offsetof()'. Use
the new 'offsetof()' instead.

Rename two variables btw:

* offsetof_num -> num_off
* percpu_data_sum -> sum

Signed-off-by: Leon Hwang 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20260814173206.93082-6-leon.hwang@linux.dev

selftests/bpf: Verify bpf_iter for global percpu data

2026-08-13T17:27:41+00:00

Add a test to verify that it is OK to iter the percpu_array map used for
global percpu data.

Signed-off-by: Leon Hwang 
Signed-off-by: Andrii Nakryiko 
Reviewed-by: Emil Tsalapatis 
Link: https://lore.kernel.org/bpf/20260813152324.97937-11-leon.hwang@linux.dev

selftests/bpf: Test verifier log for global percpu data

2026-08-13T17:27:40+00:00

Add two tests to verify the verifier log
"R%d points to percpu_array map which cannot be used as const string\n".

Signed-off-by: Leon Hwang 
Signed-off-by: Andrii Nakryiko 
Reviewed-by: Emil Tsalapatis 
Link: https://lore.kernel.org/bpf/20260813152324.97937-10-leon.hwang@linux.dev

selftests/bpf: Add tests to verify global percpu data

2026-08-13T17:27:40+00:00

If the arch, like s390x, does not support percpu insn, these cases won't
test global percpu data by checking FEAT_PERCPU_DATA support.

The following APIs have been tested for global percpu data:

1. bpf_map__set_initial_value()
2. bpf_map__initial_value()
3. bpf_map__set_value_size()
4. generated percpu struct pointer pointing to internal map's mmaped data
5. bpf_map__lookup_elem() for global percpu data map
6. bpf_map_lookup_elem_flags() for global percpu data map

At the same time, the case is also tested with 'bpftool gen skeleton -L'.

Assisted-by: Codex:gpt-5.5-xhigh
Signed-off-by: Leon Hwang 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20260813152324.97937-8-leon.hwang@linux.dev