This is a note to let you know that I've just added the patch titled
tcp/dccp: bypass empty buckets in inet_twsk_purge()
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tcp-dccp-bypass-empty-buckets-in-inet_twsk_purge.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 614f24195b077b90c89c35b118dd4544c4afda2f
Author: Eric Dumazet <edumazet@xxxxxxxxxx>
Date: Wed Mar 27 19:12:06 2024 +0000
tcp/dccp: bypass empty buckets in inet_twsk_purge()
[ Upstream commit 50e2907ef8bb52cf80ecde9eec5c4dac07177146 ]
TCP ehash table is often sparsely populated.
inet_twsk_purge() spends too much time calling cond_resched().
This patch can reduce time spent in inet_twsk_purge() by 20x.
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Reviewed-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240327191206.508114-1-edumazet@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Stable-dep-of: 565d121b6998 ("tcp: prevent concurrent execution of tcp_sk_exit_batch")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/ipv4/inet_timewait_sock.c b/net/ipv4/inet_timewait_sock.c
index 757ae3a4e2f1a..55f60d1b46f2d 100644
--- a/net/ipv4/inet_timewait_sock.c
+++ b/net/ipv4/inet_timewait_sock.c
@@ -281,12 +281,17 @@ EXPORT_SYMBOL_GPL(__inet_twsk_schedule);
/* Remove all non full sockets (TIME_WAIT and NEW_SYN_RECV) for dead netns */
void inet_twsk_purge(struct inet_hashinfo *hashinfo, int family)
{
+ struct inet_ehash_bucket *head = &hashinfo->ehash[0];
+ unsigned int ehash_mask = hashinfo->ehash_mask;
struct hlist_nulls_node *node;
unsigned int slot;
struct sock *sk;
- for (slot = 0; slot <= hashinfo->ehash_mask; slot++) {
- struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
+ for (slot = 0; slot <= ehash_mask; slot++, head++) {
+
+ if (hlist_nulls_empty(&head->chain))
+ continue;
+
restart_rcu:
cond_resched();
rcu_read_lock();
