From: Hou Tao <houtao1@xxxxxxxxxx>
The update of element in fd htab is in-place now, therefore, there is no
need to allocate per-cpu extra_elems, just remove it.
Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx>
---
kernel/bpf/hashtab.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index d0c10a899beb8..36236d806bac7 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -226,9 +226,13 @@ static struct htab_elem *get_htab_elem(struct bpf_htab *htab, int i)
return (struct htab_elem *) (htab->elems + i * (u64)htab->elem_size);
}
+/* Both percpu and fd htab support in-place update, so no need for
+ * extra elem. LRU itself can remove the least used element, so
+ * there is no need for an extra elem during map_update.
+ */
static bool htab_has_extra_elems(struct bpf_htab *htab)
{
- return !htab_is_percpu(htab) && !htab_is_lru(htab);
+ return !htab_is_percpu(htab) && !htab_is_lru(htab) && !is_fd_htab(htab);
}
static void htab_free_prealloced_timers_and_wq(struct bpf_htab *htab)
@@ -484,8 +488,6 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
{
bool percpu = (attr->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
attr->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH);
- bool lru = (attr->map_type == BPF_MAP_TYPE_LRU_HASH ||
- attr->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH);
/* percpu_lru means each cpu has its own LRU list.
* it is different from BPF_MAP_TYPE_PERCPU_HASH where
* the map's value itself is percpu. percpu_lru has
@@ -591,10 +593,7 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
if (err)
goto free_map_locked;
- if (!percpu && !lru) {
- /* lru itself can remove the least used element, so
- * there is no need for an extra elem during map_update.
- */
+ if (htab_has_extra_elems(htab)) {
err = alloc_extra_elems(htab);
if (err)
goto free_prealloc;
--
2.29.2
