diff options
| -rw-r--r-- | kernel/bpf/bpf_local_storage.c | 40 |
1 files changed, 21 insertions, 19 deletions
diff --git a/kernel/bpf/bpf_local_storage.c b/kernel/bpf/bpf_local_storage.c index 2bf5ca5ae0df..d7db1ada2dad 100644 --- a/kernel/bpf/bpf_local_storage.c +++ b/kernel/bpf/bpf_local_storage.c @@ -164,16 +164,28 @@ static void bpf_local_storage_free(struct bpf_local_storage *local_storage, bpf_local_storage_free_trace_rcu); } -/* rcu tasks trace callback for use_kmalloc_nolock == false */ -static void __bpf_selem_free_trace_rcu(struct rcu_head *rcu) +/* rcu callback for use_kmalloc_nolock == false */ +static void __bpf_selem_free_rcu(struct rcu_head *rcu) { struct bpf_local_storage_elem *selem; + struct bpf_local_storage_map *smap; selem = container_of(rcu, struct bpf_local_storage_elem, rcu); + /* bpf_selem_unlink_nofail may have already cleared smap and freed fields. */ + smap = rcu_dereference_check(SDATA(selem)->smap, 1); + + if (smap) + bpf_obj_free_fields(smap->map.record, SDATA(selem)->data); + kfree(selem); +} + +/* rcu tasks trace callback for use_kmalloc_nolock == false */ +static void __bpf_selem_free_trace_rcu(struct rcu_head *rcu) +{ if (rcu_trace_implies_rcu_gp()) - kfree(selem); + __bpf_selem_free_rcu(rcu); else - kfree_rcu(selem, rcu); + call_rcu(rcu, __bpf_selem_free_rcu); } /* Handle use_kmalloc_nolock == false */ @@ -181,7 +193,7 @@ static void __bpf_selem_free(struct bpf_local_storage_elem *selem, bool vanilla_rcu) { if (vanilla_rcu) - kfree_rcu(selem, rcu); + call_rcu(&selem->rcu, __bpf_selem_free_rcu); else call_rcu_tasks_trace(&selem->rcu, __bpf_selem_free_trace_rcu); } @@ -195,11 +207,8 @@ static void bpf_selem_free_rcu(struct rcu_head *rcu) /* The bpf_local_storage_map_free will wait for rcu_barrier */ smap = rcu_dereference_check(SDATA(selem)->smap, 1); - if (smap) { - migrate_disable(); + if (smap) bpf_obj_free_fields(smap->map.record, SDATA(selem)->data); - migrate_enable(); - } kfree_nolock(selem); } @@ -214,18 +223,12 @@ static void bpf_selem_free_trace_rcu(struct rcu_head *rcu) void bpf_selem_free(struct bpf_local_storage_elem *selem, bool reuse_now) { - struct bpf_local_storage_map *smap; - - smap = rcu_dereference_check(SDATA(selem)->smap, bpf_rcu_lock_held()); - if (!selem->use_kmalloc_nolock) { /* * No uptr will be unpin even when reuse_now == false since uptr * is only supported in task local storage, where * smap->use_kmalloc_nolock == true. */ - if (smap) - bpf_obj_free_fields(smap->map.record, SDATA(selem)->data); __bpf_selem_free(selem, reuse_now); return; } @@ -958,10 +961,9 @@ restart: */ synchronize_rcu(); - if (smap->use_kmalloc_nolock) { - rcu_barrier_tasks_trace(); - rcu_barrier(); - } + /* smap remains in use regardless of kmalloc_nolock, so wait unconditionally. */ + rcu_barrier_tasks_trace(); + rcu_barrier(); kvfree(smap->buckets); bpf_map_area_free(smap); } |