mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-09-22 12:44:11 +08:00
d71962f3e6
Helpers that expect ARG_PTR_TO_MAP_KEY and ARG_PTR_TO_MAP_VALUE can only
access stack and packet memory. Allow these helpers to directly access
map values by passing registers of type PTR_TO_MAP_VALUE.
This change removes the need for an extra copy to the stack when using a
map value to perform a second map lookup, as in the following:
struct bpf_map_def SEC("maps") infobyreq = {
.type = BPF_MAP_TYPE_HASHMAP,
.key_size = sizeof(struct request *),
.value_size = sizeof(struct info_t),
.max_entries = 1024,
};
struct bpf_map_def SEC("maps") counts = {
.type = BPF_MAP_TYPE_HASHMAP,
.key_size = sizeof(struct info_t),
.value_size = sizeof(u64),
.max_entries = 1024,
};
SEC("kprobe/blk_account_io_start")
int bpf_blk_account_io_start(struct pt_regs *ctx)
{
struct info_t *info = bpf_map_lookup_elem(&infobyreq, &ctx->di);
u64 *count = bpf_map_lookup_elem(&counts, info);
(*count)++;
}
Signed-off-by: Paul Chaignon <paul.chaignon@orange.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
|
||
|---|---|---|
| .. | ||
| arraymap.c | ||
| bpf_lru_list.c | ||
| bpf_lru_list.h | ||
| btf.c | ||
| cgroup.c | ||
| core.c | ||
| cpumap.c | ||
| devmap.c | ||
| disasm.c | ||
| disasm.h | ||
| hashtab.c | ||
| helpers.c | ||
| inode.c | ||
| lpm_trie.c | ||
| Makefile | ||
| map_in_map.c | ||
| map_in_map.h | ||
| offload.c | ||
| percpu_freelist.c | ||
| percpu_freelist.h | ||
| sockmap.c | ||
| stackmap.c | ||
| syscall.c | ||
| tnum.c | ||
| verifier.c | ||