diff options
Diffstat (limited to 'kernel/bpf/memalloc.c')
| -rw-r--r-- | kernel/bpf/memalloc.c | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index 8f0d65f2474a..04d96d1b98a3 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -171,9 +171,24 @@ static void alloc_bulk(struct bpf_mem_cache *c, int cnt, int node) memcg = get_memcg(c); old_memcg = set_active_memcg(memcg); for (i = 0; i < cnt; i++) { - obj = __alloc(c, node); - if (!obj) - break; + /* + * free_by_rcu is only manipulated by irq work refill_work(). + * IRQ works on the same CPU are called sequentially, so it is + * safe to use __llist_del_first() here. If alloc_bulk() is + * invoked by the initial prefill, there will be no running + * refill_work(), so __llist_del_first() is fine as well. + * + * In most cases, objects on free_by_rcu are from the same CPU. + * If some objects come from other CPUs, it doesn't incur any + * harm because NUMA_NO_NODE means the preference for current + * numa node and it is not a guarantee. + */ + obj = __llist_del_first(&c->free_by_rcu); + if (!obj) { + obj = __alloc(c, node); + if (!obj) + break; + } if (IS_ENABLED(CONFIG_PREEMPT_RT)) /* In RT irq_work runs in per-cpu kthread, so disable * interrupts to avoid preemption and interrupts and |