diff options
| author | Lorenz Bauer <lmb@cloudflare.com> | 2018-11-16 11:41:08 +0000 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2018-11-20 00:53:39 +0100 |
| commit | 96b3b6c9091d23289721350e32c63cc8749686be (patch) | |
| tree | 94552c4164204873c93534fb2383044e122d0488 /include | |
| parent | 23499442c319412aa8e54e7a939e2eb531bdd77d (diff) | |
bpf: allow zero-initializing hash map seed
Add a new flag BPF_F_ZERO_SEED, which forces a hash map
to initialize the seed to zero. This is useful when doing
performance analysis both on individual BPF programs, as
well as the kernel's hash table implementation.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/uapi/linux/bpf.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 47d606d744cc..8c01b89a4cb4 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -269,6 +269,9 @@ enum bpf_attach_type { /* Flag for stack_map, store build_id+offset instead of pointer */ #define BPF_F_STACK_BUILD_ID (1U << 5) +/* Zero-initialize hash function seed. This should only be used for testing. */ +#define BPF_F_ZERO_SEED (1U << 6) + enum bpf_stack_build_id_status { /* user space need an empty entry to identify end of a trace */ BPF_STACK_BUILD_ID_EMPTY = 0, |