mirrors/linux
2
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-08-27 21:03:31 -04:00
Code Issues Packages Projects Releases Wiki Activity

bpf: Factor stackid_new_bucket from __bpf_get_stackid

Browse Source 
The new stackid_new_bucket allocates the new bucket and initializes it
with the trace data.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260803210149.296496-4-jolsa@kernel.org
This commit is contained in:
Jiri Olsa
2026-08-03 23:01:40 +02:00
committed by Andrii Nakryiko
parent 0ca56befcf
commit bb4e6f4e1b
1 changed files with 30 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files

48
kernel/bpf/stackmap.c
View File

@@ -559,31 +559,52 @@ static int stackid_fastpath(struct stackid *stackid, struct bpf_map *map,
return -ENOENT;
}
static struct stack_map_bucket *
stackid_new_bucket(struct stackid *stackid, struct bpf_map *map)
{
struct bpf_stack_map *smap = container_of(map, struct bpf_stack_map, map);
struct bpf_stack_build_id *id_offs;
struct stack_map_bucket *bucket;
u32 i;
bucket = (struct stack_map_bucket *) pcpu_freelist_pop(&smap->freelist);
if (unlikely(!bucket))
return NULL;
if (stack_map_use_build_id(map)) {
id_offs = (struct bpf_stack_build_id *)bucket->data;
for (i = 0; i < stackid->nr; i++)
id_offs[i].ip = stackid->ips[i];
} else {
memcpy(bucket->data, stackid->ips, stackid->len);
}
bucket->hash = stackid->hash;
bucket->nr = stackid->nr;
return bucket;
}
static long __bpf_get_stackid(struct stackid *stackid, struct bpf_map *map,
struct perf_callchain_entry *trace, u64 flags)
{
struct bpf_stack_map *smap = container_of(map, struct bpf_stack_map, map);
struct stack_map_bucket *new_bucket, *old_bucket;
bool user = flags & BPF_F_USER_STACK;
u32 trace_len, i;
u32 trace_len;
int err;
err = stackid_fastpath(stackid, map, trace, flags);
if (err != -ENOENT)
return err;
new_bucket = stackid_new_bucket(stackid, map);
if (!new_bucket)
return -ENOMEM;
if (stack_map_use_build_id(map)) {
struct bpf_stack_build_id *id_offs;
/* for build_id+offset, pop a bucket before slow cmp */
new_bucket = (struct stack_map_bucket *)
pcpu_freelist_pop(&smap->freelist);
if (unlikely(!new_bucket))
return -ENOMEM;
new_bucket->nr = stackid->nr;
id_offs = (struct bpf_stack_build_id *)new_bucket->data;
for (i = 0; i < stackid->nr; i++)
id_offs[i].ip = stackid->ips[i];
stack_map_get_build_id_offset(id_offs, stackid->nr, user, false /* !may_fault */);
trace_len = stackid->nr * sizeof(struct bpf_stack_build_id);
if (stackid->hash_matches && stackid->bucket->nr == stackid->nr &&
@@ -595,17 +616,8 @@ static long __bpf_get_stackid(struct stackid *stackid, struct bpf_map *map,
pcpu_freelist_push(&smap->freelist, &new_bucket->fnode);
return -EEXIST;
}
} else {
new_bucket = (struct stack_map_bucket *)
pcpu_freelist_pop(&smap->freelist);
if (unlikely(!new_bucket))
return -ENOMEM;
memcpy(new_bucket->data, stackid->ips, stackid->len);
}
new_bucket->hash = stackid->hash;
new_bucket->nr = stackid->nr;
old_bucket = xchg(&smap->buckets[stackid->id], new_bucket);
if (old_bucket)
pcpu_freelist_push(&smap->freelist, &old_bucket->fnode);