Hi,
On 12/15/2023 8:12 AM, Yonghong Song wrote:
> In the previous patch, the maximum data size for bpf_global_percpu_ma
> is 512 bytes. This breaks selftest test_bpf_ma. Let us adjust it
> accordingly. Also added a selftest to capture the verification failure
> when the allocation size is greater than 512.
>
> Signed-off-by: Yonghong Song <yonghong.song@xxxxxxxxx>
> ---
> .../selftests/bpf/progs/percpu_alloc_fail.c | 18 ++++++++++++++++++
> .../testing/selftests/bpf/progs/test_bpf_ma.c | 9 ---------
> 2 files changed, 18 insertions(+), 9 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/progs/percpu_alloc_fail.c b/tools/testing/selftests/bpf/progs/percpu_alloc_fail.c
> index 1a891d30f1fe..f2b8eb2ff76f 100644
> --- a/tools/testing/selftests/bpf/progs/percpu_alloc_fail.c
> +++ b/tools/testing/selftests/bpf/progs/percpu_alloc_fail.c
> @@ -17,6 +17,10 @@ struct val_with_rb_root_t {
> struct bpf_spin_lock lock;
> };
>
> +struct val_600b_t {
> + char b[600];
> +};
> +
> struct elem {
> long sum;
> struct val_t __percpu_kptr *pc;
> @@ -161,4 +165,18 @@ int BPF_PROG(test_array_map_7)
> return 0;
> }
>
> +SEC("?fentry.s/bpf_fentry_test1")
> +__failure __msg("bpf_percpu_obj_new type size (600) is greater than 512")
> +int BPF_PROG(test_array_map_8)
> +{
> + struct val_600b_t __percpu_kptr *p;
> +
> + p = bpf_percpu_obj_new(struct val_600b_t);
> + if (!p)
> + return 0;
> +
> + bpf_percpu_obj_drop(p);
> + return 0;
> +}
> +
> char _license[] SEC("license") = "GPL";
> diff --git a/tools/testing/selftests/bpf/progs/test_bpf_ma.c b/tools/testing/selftests/bpf/progs/test_bpf_ma.c
> index b685a4aba6bd..68cba55eb828 100644
> --- a/tools/testing/selftests/bpf/progs/test_bpf_ma.c
> +++ b/tools/testing/selftests/bpf/progs/test_bpf_ma.c
> @@ -188,9 +188,6 @@ DEFINE_ARRAY_WITH_PERCPU_KPTR(128);
> DEFINE_ARRAY_WITH_PERCPU_KPTR(192);
> DEFINE_ARRAY_WITH_PERCPU_KPTR(256);
> DEFINE_ARRAY_WITH_PERCPU_KPTR(512);
> -DEFINE_ARRAY_WITH_PERCPU_KPTR(1024);
> -DEFINE_ARRAY_WITH_PERCPU_KPTR(2048);
> -DEFINE_ARRAY_WITH_PERCPU_KPTR(4096);
Considering the update in patch "bpf: Avoid unnecessary extra percpu
memory allocation", the definition of DEFINE_ARRAY_WITH_PERCPU_KPTR()
needs update as well, because for 512-sized per-cpu kptr, the tests only
allocate for (512 - sizeof(void *)) bytes. And we could do
DEFINE_ARRAY_WITH_PERCPU_KPTR(8) test after the update. I could do that
after the patch-set is landed if you don't have time to do that.
A bit of off-topic, but it is still relevant. I have a question about
how to forcibly generate BTF info for struct definition in the test ?
Currently, I have to include bin_data_xx in the definition of
map_value, but I don't want to increase the size of map_value. I had
tried to use BTF_TYPE_EMIT() in prog just like in linux kernel, but it
didn't work.
>
> SEC("?fentry/" SYS_PREFIX "sys_nanosleep")
> int test_batch_alloc_free(void *ctx)
> @@ -259,9 +256,6 @@ int test_batch_percpu_alloc_free(void *ctx)
> CALL_BATCH_PERCPU_ALLOC_FREE(192, 128, 6);
> CALL_BATCH_PERCPU_ALLOC_FREE(256, 128, 7);
> CALL_BATCH_PERCPU_ALLOC_FREE(512, 64, 8);
> - CALL_BATCH_PERCPU_ALLOC_FREE(1024, 32, 9);
> - CALL_BATCH_PERCPU_ALLOC_FREE(2048, 16, 10);
> - CALL_BATCH_PERCPU_ALLOC_FREE(4096, 8, 11);
>
> return 0;
> }
> @@ -283,9 +277,6 @@ int test_percpu_free_through_map_free(void *ctx)
> CALL_BATCH_PERCPU_ALLOC(192, 128, 6);
> CALL_BATCH_PERCPU_ALLOC(256, 128, 7);
> CALL_BATCH_PERCPU_ALLOC(512, 64, 8);
> - CALL_BATCH_PERCPU_ALLOC(1024, 32, 9);
> - CALL_BATCH_PERCPU_ALLOC(2048, 16, 10);
> - CALL_BATCH_PERCPU_ALLOC(4096, 8, 11);
>
> return 0;
> }
