Commit 9087c6ff authored by Eric Dumazet's avatar Eric Dumazet Committed by Daniel Borkmann
Browse files

bpf: Call maybe_wait_bpf_programs() only once from generic_map_delete_batch() 



As stated in the comment found in maybe_wait_bpf_programs(),
the synchronize_rcu() barrier is only needed before returning
to userspace, not after each deletion in the batch.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: default avatarStanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20220218181801.2971275-1-eric.dumazet@gmail.com
parent 086d4905

kernel/bpf/syscall.c

+2 −1
Original line number Diff line number Diff line
@@ -1352,7 +1352,6 @@ int generic_map_delete_batch(struct bpf_map *map, 
		err = map->ops->map_delete_elem(map, key);

		rcu_read_unlock();

		bpf_enable_instrumentation();

		maybe_wait_bpf_programs(map);

		if (err)

			break;

		cond_resched();
@@ -1361,6 +1360,8 @@ int generic_map_delete_batch(struct bpf_map *map, 
		err = -EFAULT;



	kvfree(key);



	maybe_wait_bpf_programs(map);

	return err;

}