diff --git a/include/linux/bpf.h b/include/linux/bpf.h index a98c833461347..d808253f2e945 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -2499,6 +2499,8 @@ int bpf_map_alloc_pages(const struct bpf_map *map, int nid, #ifdef CONFIG_MEMCG void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags, int node); +void *bpf_map_kmalloc_nolock(const struct bpf_map *map, size_t size, gfp_t flags, + int node); void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags); void *bpf_map_kvcalloc(struct bpf_map *map, size_t n, size_t size, gfp_t flags); @@ -2511,6 +2513,8 @@ void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size, */ #define bpf_map_kmalloc_node(_map, _size, _flags, _node) \ kmalloc_node(_size, _flags, _node) +#define bpf_map_kmalloc_nolock(_map, _size, _flags, _node) \ + kmalloc_nolock(_size, _flags, _node) #define bpf_map_kzalloc(_map, _size, _flags) \ kzalloc(_size, _flags) #define bpf_map_kvcalloc(_map, _n, _size, _flags) \ diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index c9fab9a356dfc..c5f63f2685e99 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -1215,13 +1215,20 @@ static void bpf_wq_work(struct work_struct *work) rcu_read_unlock_trace(); } +static void bpf_async_cb_rcu_free(struct rcu_head *rcu) +{ + struct bpf_async_cb *cb = container_of(rcu, struct bpf_async_cb, rcu); + + kfree_nolock(cb); +} + static void bpf_wq_delete_work(struct work_struct *work) { struct bpf_work *w = container_of(work, struct bpf_work, delete_work); cancel_work_sync(&w->work); - kfree_rcu(w, cb.rcu); + call_rcu(&w->cb.rcu, bpf_async_cb_rcu_free); } static void bpf_timer_delete_work(struct work_struct *work) @@ -1230,13 +1237,13 @@ static void bpf_timer_delete_work(struct work_struct *work) /* Cancel the timer and wait for callback to complete if it was running. * If hrtimer_cancel() can be safely called it's safe to call - * kfree_rcu(t) right after for both preallocated and non-preallocated + * call_rcu() right after for both preallocated and non-preallocated * maps. The async->cb = NULL was already done and no code path can see * address 't' anymore. Timer if armed for existing bpf_hrtimer before * bpf_timer_cancel_and_free will have been cancelled. */ hrtimer_cancel(&t->timer); - kfree_rcu(t, cb.rcu); + call_rcu(&t->cb.rcu, bpf_async_cb_rcu_free); } static int __bpf_async_init(struct bpf_async_kern *async, struct bpf_map *map, u64 flags, @@ -1270,11 +1277,7 @@ static int __bpf_async_init(struct bpf_async_kern *async, struct bpf_map *map, u goto out; } - /* Allocate via bpf_map_kmalloc_node() for memcg accounting. Until - * kmalloc_nolock() is available, avoid locking issues by using - * __GFP_HIGH (GFP_ATOMIC & ~__GFP_RECLAIM). - */ - cb = bpf_map_kmalloc_node(map, size, __GFP_HIGH, map->numa_node); + cb = bpf_map_kmalloc_nolock(map, size, 0, map->numa_node); if (!cb) { ret = -ENOMEM; goto out; @@ -1607,7 +1610,7 @@ void bpf_timer_cancel_and_free(void *val) * completion. */ if (hrtimer_try_to_cancel(&t->timer) >= 0) - kfree_rcu(t, cb.rcu); + call_rcu(&t->cb.rcu, bpf_async_cb_rcu_free); else queue_work(system_dfl_wq, &t->cb.delete_work); } else { diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 2a9456a3e7304..8a129746bd6cc 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -520,6 +520,21 @@ void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags, return ptr; } +void *bpf_map_kmalloc_nolock(const struct bpf_map *map, size_t size, gfp_t flags, + int node) +{ + struct mem_cgroup *memcg, *old_memcg; + void *ptr; + + memcg = bpf_map_get_memcg(map); + old_memcg = set_active_memcg(memcg); + ptr = kmalloc_nolock(size, flags | __GFP_ACCOUNT, node); + set_active_memcg(old_memcg); + mem_cgroup_put(memcg); + + return ptr; +} + void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags) { struct mem_cgroup *memcg, *old_memcg;