6.1-stable review patch. If anyone has any objections, please let me know.
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From: Eric Dumazet edumazet@google.com
[ Upstream commit 50b362f21d6c10b0f7939c1482c6a1b43da82f1a ]
inet_putpeer() will be removed in the following patch, because we will no longer use refcounts.
Update inetpeer timestamp (p->dtime) at lookup time.
Signed-off-by: Eric Dumazet edumazet@google.com Link: https://patch.msgid.link/20241215175629.1248773-4-edumazet@google.com Signed-off-by: Jakub Kicinski kuba@kernel.org Stable-dep-of: a853c609504e ("inetpeer: do not get a refcount in inet_getpeer()") Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/inetpeer.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-)
diff --git a/net/ipv4/inetpeer.c b/net/ipv4/inetpeer.c index 5670571ee5fbe..596e2c3a8551f 100644 --- a/net/ipv4/inetpeer.c +++ b/net/ipv4/inetpeer.c @@ -98,6 +98,7 @@ static struct inet_peer *lookup(const struct inetpeer_addr *daddr, { struct rb_node **pp, *parent, *next; struct inet_peer *p; + u32 now;
pp = &base->rb_root.rb_node; parent = NULL; @@ -113,6 +114,9 @@ static struct inet_peer *lookup(const struct inetpeer_addr *daddr, if (cmp == 0) { if (!refcount_inc_not_zero(&p->refcnt)) break; + now = jiffies; + if (READ_ONCE(p->dtime) != now) + WRITE_ONCE(p->dtime, now); return p; } if (gc_stack) { @@ -158,9 +162,6 @@ static void inet_peer_gc(struct inet_peer_base *base, for (i = 0; i < gc_cnt; i++) { p = gc_stack[i];
- /* The READ_ONCE() pairs with the WRITE_ONCE() - * in inet_putpeer() - */ delta = (__u32)jiffies - READ_ONCE(p->dtime);
if (delta < ttl || !refcount_dec_if_one(&p->refcnt)) @@ -232,11 +233,6 @@ EXPORT_SYMBOL_GPL(inet_getpeer);
void inet_putpeer(struct inet_peer *p) { - /* The WRITE_ONCE() pairs with itself (we run lockless) - * and the READ_ONCE() in inet_peer_gc() - */ - WRITE_ONCE(p->dtime, (__u32)jiffies); - if (refcount_dec_and_test(&p->refcnt)) call_rcu(&p->rcu, inetpeer_free_rcu); }