On Fri, Mar 26, 2021 at 5:24 AM Yauheni Kaliuta
<yauheni.kaliuta@xxxxxxxxxx> wrote:
>
> Both ringbuf and mmap need PAGE_SIZE, but it's not available during
> bpf program compile time. 4K size was hardcoded (page shift 12 bits)
> which makes the tests fail on systems, configured for larger pages.
>
> Bump it up to 64K which at the first glance look reasonable at the
> moment for most of the systems.
>
> Use define to make it clear.
>
> Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@xxxxxxxxxx>
> ---
> tools/testing/selftests/bpf/prog_tests/ringbuf.c | 9 +++++++--
> tools/testing/selftests/bpf/progs/map_ptr_kern.c | 9 +++++++--
> tools/testing/selftests/bpf/progs/test_mmap.c | 10 ++++++++--
> tools/testing/selftests/bpf/progs/test_ringbuf.c | 8 +++++++-
> tools/testing/selftests/bpf/progs/test_ringbuf_multi.c | 7 ++++++-
> 5 files changed, 35 insertions(+), 8 deletions(-)
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/ringbuf.c b/tools/testing/selftests/bpf/prog_tests/ringbuf.c
> index fddbc5db5d6a..9057654da957 100644
> --- a/tools/testing/selftests/bpf/prog_tests/ringbuf.c
> +++ b/tools/testing/selftests/bpf/prog_tests/ringbuf.c
> @@ -15,6 +15,11 @@
> #include "test_ringbuf.skel.h"
>
> #define EDONE 7777
> +#ifdef PAGE_SIZE
> +#undef PAGE_SIZE
> +#endif
> +/* this is not actual page size, but the value used for ringbuf */
> +#define PAGE_SIZE 65536
>
> static int duration = 0;
>
> @@ -110,9 +115,9 @@ void test_ringbuf(void)
> CHECK(skel->bss->avail_data != 3 * rec_sz,
> "err_avail_size", "exp %ld, got %ld\n",
> 3L * rec_sz, skel->bss->avail_data);
> - CHECK(skel->bss->ring_size != 4096,
> + CHECK(skel->bss->ring_size != PAGE_SIZE,
> "err_ring_size", "exp %ld, got %ld\n",
> - 4096L, skel->bss->ring_size);
> + (long)PAGE_SIZE, skel->bss->ring_size);
> CHECK(skel->bss->cons_pos != 0,
> "err_cons_pos", "exp %ld, got %ld\n",
> 0L, skel->bss->cons_pos);
> diff --git a/tools/testing/selftests/bpf/progs/map_ptr_kern.c b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
> index d8850bc6a9f1..c1460f27af78 100644
> --- a/tools/testing/selftests/bpf/progs/map_ptr_kern.c
> +++ b/tools/testing/selftests/bpf/progs/map_ptr_kern.c
> @@ -8,6 +8,11 @@
> #define MAX_ENTRIES 8
> #define HALF_ENTRIES (MAX_ENTRIES >> 1)
>
> +#ifndef PAGE_SIZE
> +/* use reasonable value for various configurations */
> +#define PAGE_SIZE 65536
> +#endif
> +
> _Static_assert(MAX_ENTRIES < LOOP_BOUND, "MAX_ENTRIES must be < LOOP_BOUND");
>
> enum bpf_map_type g_map_type = BPF_MAP_TYPE_UNSPEC;
> @@ -635,7 +640,7 @@ struct bpf_ringbuf_map {
>
> struct {
> __uint(type, BPF_MAP_TYPE_RINGBUF);
> - __uint(max_entries, 1 << 12);
> + __uint(max_entries, PAGE_SIZE);
> } m_ringbuf SEC(".maps");
>
> static inline int check_ringbuf(void)
> @@ -643,7 +648,7 @@ static inline int check_ringbuf(void)
> struct bpf_ringbuf_map *ringbuf = (struct bpf_ringbuf_map *)&m_ringbuf;
> struct bpf_map *map = (struct bpf_map *)&m_ringbuf;
>
> - VERIFY(check(&ringbuf->map, map, 0, 0, 1 << 12));
> + VERIFY(check(&ringbuf->map, map, 0, 0, PAGE_SIZE));
>
> return 1;
> }
> diff --git a/tools/testing/selftests/bpf/progs/test_mmap.c b/tools/testing/selftests/bpf/progs/test_mmap.c
> index 4eb42cff5fe9..c22fcfea0767 100644
> --- a/tools/testing/selftests/bpf/progs/test_mmap.c
> +++ b/tools/testing/selftests/bpf/progs/test_mmap.c
> @@ -5,11 +5,16 @@
> #include <stdint.h>
> #include <bpf/bpf_helpers.h>
>
> +#ifndef PAGE_SIZE
> +/* use reasonable value for various configurations */
> +#define PAGE_SIZE 65536
> +#endif
> +
> char _license[] SEC("license") = "GPL";
>
> struct {
> __uint(type, BPF_MAP_TYPE_ARRAY);
> - __uint(max_entries, 4096);
> + __uint(max_entries, PAGE_SIZE);
so you can set map size at runtime before bpf_object__load (or
skeleton's load) with bpf_map__set_max_entries. That way you don't
have to do any assumptions. Just omit max_entries in BPF source code,
and always set it in userspace.
> __uint(map_flags, BPF_F_MMAPABLE | BPF_F_RDONLY_PROG);
> __type(key, __u32);
> __type(value, char);
> @@ -17,7 +22,8 @@ struct {
>
> struct {
> __uint(type, BPF_MAP_TYPE_ARRAY);
> - __uint(max_entries, 512 * 4); /* at least 4 pages of data */
> + /* at least 4 pages of data */
> + __uint(max_entries, 4 * (PAGE_SIZE / sizeof (__u64)));
> __uint(map_flags, BPF_F_MMAPABLE);
> __type(key, __u32);
> __type(value, __u64);
> diff --git a/tools/testing/selftests/bpf/progs/test_ringbuf.c b/tools/testing/selftests/bpf/progs/test_ringbuf.c
> index 8ba9959b036b..6e645babdc18 100644
> --- a/tools/testing/selftests/bpf/progs/test_ringbuf.c
> +++ b/tools/testing/selftests/bpf/progs/test_ringbuf.c
> @@ -4,6 +4,12 @@
> #include <linux/bpf.h>
> #include <bpf/bpf_helpers.h>
>
> +#ifndef PAGE_SIZE
> +/* use reasonable value for various configurations */
> +#define PAGE_SIZE 65536
> +#endif
> +
> +
> char _license[] SEC("license") = "GPL";
>
> struct sample {
> @@ -15,7 +21,7 @@ struct sample {
>
> struct {
> __uint(type, BPF_MAP_TYPE_RINGBUF);
> - __uint(max_entries, 1 << 12);
> + __uint(max_entries, PAGE_SIZE);
> } ringbuf SEC(".maps");
>
> /* inputs */
> diff --git a/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c b/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
> index edf3b6953533..13bcf095e06c 100644
> --- a/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
> +++ b/tools/testing/selftests/bpf/progs/test_ringbuf_multi.c
> @@ -4,6 +4,11 @@
> #include <linux/bpf.h>
> #include <bpf/bpf_helpers.h>
>
> +#ifndef PAGE_SIZE
> +/* use reasonable value for various configurations */
> +#define PAGE_SIZE 65536
> +#endif
> +
> char _license[] SEC("license") = "GPL";
>
> struct sample {
> @@ -15,7 +20,7 @@ struct sample {
>
> struct ringbuf_map {
> __uint(type, BPF_MAP_TYPE_RINGBUF);
> - __uint(max_entries, 1 << 12);
> + __uint(max_entries, PAGE_SIZE);
> } ringbuf1 SEC(".maps"),
> ringbuf2 SEC(".maps");
>
> --
> 2.29.2
>
