From b76354cdfefb68bc017065850a34d486887a4f7b Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Tue, 27 Mar 2018 11:53:21 -0700 Subject: [PATCH] bpf: follow idr code convention Generally we do a preload before doing idr allocation. This also help improve the allocation success rate in memory pressure. Cc: Daniel Borkmann Cc: Alexei Starovoitov Signed-off-by: Shaohua Li Signed-off-by: Daniel Borkmann --- kernel/bpf/syscall.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index dd172ee16716..77d45bd9f507 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -203,11 +203,13 @@ static int bpf_map_alloc_id(struct bpf_map *map) { int id; + idr_preload(GFP_KERNEL); spin_lock_bh(&map_idr_lock); id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); if (id > 0) map->id = id; spin_unlock_bh(&map_idr_lock); + idr_preload_end(); if (WARN_ON_ONCE(!id)) return -ENOSPC; @@ -940,11 +942,13 @@ static int bpf_prog_alloc_id(struct bpf_prog *prog) { int id; + idr_preload(GFP_KERNEL); spin_lock_bh(&prog_idr_lock); id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); if (id > 0) prog->aux->id = id; spin_unlock_bh(&prog_idr_lock); + idr_preload_end(); /* id is in [1, INT_MAX) */ if (WARN_ON_ONCE(!id)) -- 2.30.2