From af185d8c76333daa877678e0166a7b45e63bf3c4 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <edumazet@google.com>
Date: Mon, 20 Jun 2022 03:05:09 -0700
Subject: [PATCH] raw: complete rcu conversion
raw_diag_dump() can use rcu_read_lock() instead of read_lock()
Now the hashinfo lock is only used from process context,
in write mode only, we can convert it to a spinlock,
and we do not need to block BH anymore.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20220620100509.3493504-1-eric.dumazet@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
---
include/net/raw.h | 4 ++--
net/ipv4/raw.c | 8 ++++----
net/ipv4/raw_diag.c | 4 ++--
3 files changed, 8 insertions(+), 8 deletions(-)
diff --git a/include/net/raw.h b/include/net/raw.h
index d81eeeb8f1e6..d224376360e1 100644
--- a/include/net/raw.h
+++ b/include/net/raw.h
@@ -32,7 +32,7 @@ int raw_rcv(struct sock *, struct sk_buff *);
#define RAW_HTABLE_SIZE MAX_INET_PROTOS
struct raw_hashinfo {
- rwlock_t lock;
+ spinlock_t lock;
struct hlist_nulls_head ht[RAW_HTABLE_SIZE];
};
@@ -40,7 +40,7 @@ static inline void raw_hashinfo_init(struct raw_hashinfo *hashinfo)
{
int i;
- rwlock_init(&hashinfo->lock);
+ spin_lock_init(&hashinfo->lock);
for (i = 0; i < RAW_HTABLE_SIZE; i++)
INIT_HLIST_NULLS_HEAD(&hashinfo->ht[i], i);
}
diff --git a/net/ipv4/raw.c b/net/ipv4/raw.c
index 959bea12dc48..027389969915 100644
--- a/net/ipv4/raw.c
+++ b/net/ipv4/raw.c
@@ -95,10 +95,10 @@ int raw_hash_sk(struct sock *sk)
hlist = &h->ht[inet_sk(sk)->inet_num & (RAW_HTABLE_SIZE - 1)];
- write_lock_bh(&h->lock);
+ spin_lock(&h->lock);
__sk_nulls_add_node_rcu(sk, hlist);
sock_set_flag(sk, SOCK_RCU_FREE);
- write_unlock_bh(&h->lock);
+ spin_unlock(&h->lock);
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
return 0;
@@ -109,10 +109,10 @@ void raw_unhash_sk(struct sock *sk)
{
struct raw_hashinfo *h = sk->sk_prot->h.raw_hash;
- write_lock_bh(&h->lock);
+ spin_lock(&h->lock);
if (__sk_nulls_del_node_init_rcu(sk))
sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
- write_unlock_bh(&h->lock);
+ spin_unlock(&h->lock);
}
EXPORT_SYMBOL_GPL(raw_unhash_sk);
diff --git a/net/ipv4/raw_diag.c b/net/ipv4/raw_diag.c
index ac4b6525d3c6..999321834b94 100644
--- a/net/ipv4/raw_diag.c
+++ b/net/ipv4/raw_diag.c
@@ -156,7 +156,7 @@ static void raw_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
s_slot = cb->args[0];
num = s_num = cb->args[1];
- read_lock(&hashinfo->lock);
+ rcu_read_lock();
for (slot = s_slot; slot < RAW_HTABLE_SIZE; s_num = 0, slot++) {
num = 0;
@@ -184,7 +184,7 @@ next:
}
out_unlock:
- read_unlock(&hashinfo->lock);
+ rcu_read_unlock();
cb->args[0] = slot;
cb->args[1] = num;