| Message ID | 20210429134656.122225-3-lmb@cloudflare.com (mailing list archive) |
|---|---|
| State | Accepted |
| Delegated to: | BPF |
| Headers | show |
| Series | Reduce kmalloc / kfree churn in the verifier | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for bpf-next |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | warning | 5 maintainers not CCed: yhs@fb.com kpsingh@kernel.org kafai@fb.com john.fastabend@gmail.com songliubraving@fb.com |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 20 this patch: 20 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | warning | WARNING: line length of 85 exceeds 80 columns WARNING: line length of 94 exceeds 80 columns |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 20 this patch: 20 |
| netdev/header_inline | success | Link |
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 67d914b26a39..2b9623ac9288 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -926,16 +926,13 @@ static int copy_verifier_state(struct bpf_verifier_state *dst_state, const struct bpf_verifier_state *src) { struct bpf_func_state *dst; - u32 jmp_sz = sizeof(struct bpf_idx_pair) * src->jmp_history_cnt; int i, err; - if (dst_state->jmp_history_cnt < src->jmp_history_cnt) { - kfree(dst_state->jmp_history); - dst_state->jmp_history = kmalloc(jmp_sz, GFP_USER); - if (!dst_state->jmp_history) - return -ENOMEM; - } - memcpy(dst_state->jmp_history, src->jmp_history, jmp_sz); + dst_state->jmp_history = copy_array(dst_state->jmp_history, src->jmp_history, + src->jmp_history_cnt, sizeof(struct bpf_idx_pair), + GFP_USER); + if (!dst_state->jmp_history) + return -ENOMEM; dst_state->jmp_history_cnt = src->jmp_history_cnt; /* if dst has more stack frames then src frame, free them */
Eliminate a couple needless kfree / kmalloc cycles by using copy_array for jmp_history. Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> --- kernel/bpf/verifier.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-)