diff options
Diffstat (limited to 'kernel/bpf/bpf_cgrp_storage.c')
| -rw-r--r-- | kernel/bpf/bpf_cgrp_storage.c | 32 |
1 files changed, 16 insertions, 16 deletions
diff --git a/kernel/bpf/bpf_cgrp_storage.c b/kernel/bpf/bpf_cgrp_storage.c index 28efd0a3f220..148da8f7ff36 100644 --- a/kernel/bpf/bpf_cgrp_storage.c +++ b/kernel/bpf/bpf_cgrp_storage.c @@ -15,22 +15,20 @@ static DEFINE_PER_CPU(int, bpf_cgrp_storage_busy); static void bpf_cgrp_storage_lock(void) { - migrate_disable(); + cant_migrate(); this_cpu_inc(bpf_cgrp_storage_busy); } static void bpf_cgrp_storage_unlock(void) { this_cpu_dec(bpf_cgrp_storage_busy); - migrate_enable(); } static bool bpf_cgrp_storage_trylock(void) { - migrate_disable(); + cant_migrate(); if (unlikely(this_cpu_inc_return(bpf_cgrp_storage_busy) != 1)) { this_cpu_dec(bpf_cgrp_storage_busy); - migrate_enable(); return false; } return true; @@ -47,17 +45,18 @@ void bpf_cgrp_storage_free(struct cgroup *cgroup) { struct bpf_local_storage *local_storage; + migrate_disable(); rcu_read_lock(); local_storage = rcu_dereference(cgroup->bpf_cgrp_storage); - if (!local_storage) { - rcu_read_unlock(); - return; - } + if (!local_storage) + goto out; bpf_cgrp_storage_lock(); bpf_local_storage_destroy(local_storage); bpf_cgrp_storage_unlock(); +out: rcu_read_unlock(); + migrate_enable(); } static struct bpf_local_storage_data * @@ -107,7 +106,7 @@ static long bpf_cgrp_storage_update_elem(struct bpf_map *map, void *key, bpf_cgrp_storage_lock(); sdata = bpf_local_storage_update(cgroup, (struct bpf_local_storage_map *)map, - value, map_flags, GFP_ATOMIC); + value, map_flags, false, GFP_ATOMIC); bpf_cgrp_storage_unlock(); cgroup_put(cgroup); return PTR_ERR_OR_ZERO(sdata); @@ -154,7 +153,7 @@ static struct bpf_map *cgroup_storage_map_alloc(union bpf_attr *attr) static void cgroup_storage_map_free(struct bpf_map *map) { - bpf_local_storage_map_free(map, &cgroup_cache, NULL); + bpf_local_storage_map_free(map, &cgroup_cache, &bpf_cgrp_storage_busy); } /* *gfp_flags* is a hidden argument provided by the verifier */ @@ -162,6 +161,7 @@ BPF_CALL_5(bpf_cgrp_storage_get, struct bpf_map *, map, struct cgroup *, cgroup, void *, value, u64, flags, gfp_t, gfp_flags) { struct bpf_local_storage_data *sdata; + bool nobusy; WARN_ON_ONCE(!bpf_rcu_lock_held()); if (flags & ~(BPF_LOCAL_STORAGE_GET_F_CREATE)) @@ -170,21 +170,21 @@ BPF_CALL_5(bpf_cgrp_storage_get, struct bpf_map *, map, struct cgroup *, cgroup, if (!cgroup) return (unsigned long)NULL; - if (!bpf_cgrp_storage_trylock()) - return (unsigned long)NULL; + nobusy = bpf_cgrp_storage_trylock(); - sdata = cgroup_storage_lookup(cgroup, map, true); + sdata = cgroup_storage_lookup(cgroup, map, nobusy); if (sdata) goto unlock; /* only allocate new storage, when the cgroup is refcounted */ if (!percpu_ref_is_dying(&cgroup->self.refcnt) && - (flags & BPF_LOCAL_STORAGE_GET_F_CREATE)) + (flags & BPF_LOCAL_STORAGE_GET_F_CREATE) && nobusy) sdata = bpf_local_storage_update(cgroup, (struct bpf_local_storage_map *)map, - value, BPF_NOEXIST, gfp_flags); + value, BPF_NOEXIST, false, gfp_flags); unlock: - bpf_cgrp_storage_unlock(); + if (nobusy) + bpf_cgrp_storage_unlock(); return IS_ERR_OR_NULL(sdata) ? (unsigned long)NULL : (unsigned long)sdata->data; } |