bpf: Use rcu_read_lock_dont_migrate in bpf_sk_storage.c

Use rcu_read_lock_dont_migrate() and rcu_read_unlock_migrate() in
bpf_sk_storage.c to obtain better performance when PREEMPT_RCU is
not enabled.

Signed-off-by: Fushuai Wang <wangfushuai@baidu.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20251007074011.12916-1-wangfushuai@baidu.com

diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c
index 2e538399757fea25720a9ead6301234103133e3d..d3fbaf89a698da1e3ed593ff82bb6ec4414bbd39 100644 (file)
--- a/net/core/bpf_sk_storage.c
+++ b/net/core/bpf_sk_storage.c
@@ -50,16 +50,14 @@ void bpf_sk_storage_free(struct sock *sk)
 {
        struct bpf_local_storage *sk_storage;
 
-       migrate_disable();
-       rcu_read_lock();
+       rcu_read_lock_dont_migrate();
        sk_storage = rcu_dereference(sk->sk_bpf_storage);
        if (!sk_storage)
                goto out;
 
        bpf_local_storage_destroy(sk_storage);
 out:
-       rcu_read_unlock();
-       migrate_enable();
+       rcu_read_unlock_migrate();
 }
 
 static void bpf_sk_storage_map_free(struct bpf_map *map)
@@ -161,8 +159,7 @@ int bpf_sk_storage_clone(const struct sock *sk, struct sock *newsk)
 
        RCU_INIT_POINTER(newsk->sk_bpf_storage, NULL);
 
-       migrate_disable();
-       rcu_read_lock();
+       rcu_read_lock_dont_migrate();
        sk_storage = rcu_dereference(sk->sk_bpf_storage);
 
        if (!sk_storage || hlist_empty(&sk_storage->list))
@@ -213,8 +210,7 @@ int bpf_sk_storage_clone(const struct sock *sk, struct sock *newsk)
        }
 
 out:
-       rcu_read_unlock();
-       migrate_enable();
+       rcu_read_unlock_migrate();
 
        /* In case of an error, don't free anything explicitly here, the
         * caller is responsible to call bpf_sk_storage_free.