kernel: remove support for kernel 4.9

[openwrt/staging/dedeckeh.git] / target / linux / generic / backport-4.9 / 024-4-tcp-tsq-avoid-one-atomic-in-tcp_wfree.patch

diff --git a/target/linux/generic/backport-4.9/024-4-tcp-tsq-avoid-one-atomic-in-tcp_wfree.patch b/target/linux/generic/backport-4.9/024-4-tcp-tsq-avoid-one-atomic-in-tcp_wfree.patch
deleted file mode 100644 (file)
index 2b5ef93..0000000
--- a/target/linux/generic/backport-4.9/024-4-tcp-tsq-avoid-one-atomic-in-tcp_wfree.patch
+++ /dev/null
@@ -1,38 +0,0 @@
-From a9b204d1564702b704ad6fe74f10a102c7b87ba3 Mon Sep 17 00:00:00 2001
-From: Eric Dumazet <edumazet@google.com>
-Date: Sat, 3 Dec 2016 11:14:53 -0800
-Subject: [PATCH 04/10] tcp: tsq: avoid one atomic in tcp_wfree()
-
-Under high load, tcp_wfree() has an atomic operation trying
-to schedule a tasklet over and over.
-
-We can schedule it only if our per cpu list was empty.
-
-Signed-off-by: Eric Dumazet <edumazet@google.com>
-Signed-off-by: David S. Miller <davem@davemloft.net>
----
- net/ipv4/tcp_output.c | 5 ++++-
- 1 file changed, 4 insertions(+), 1 deletion(-)
-
---- a/net/ipv4/tcp_output.c
-+++ b/net/ipv4/tcp_output.c
-@@ -886,6 +886,7 @@ void tcp_wfree(struct sk_buff *skb)
- 
-       for (oval = READ_ONCE(tp->tsq_flags);; oval = nval) {
-               struct tsq_tasklet *tsq;
-+              bool empty;
- 
-               if (!(oval & TSQF_THROTTLED) || (oval & TSQF_QUEUED))
-                       goto out;
-@@ -898,8 +899,10 @@ void tcp_wfree(struct sk_buff *skb)
-               /* queue this socket to tasklet queue */
-               local_irq_save(flags);
-               tsq = this_cpu_ptr(&tsq_tasklet);
-+              empty = list_empty(&tsq->head);
-               list_add(&tp->tsq_node, &tsq->head);
--              tasklet_schedule(&tsq->tasklet);
-+              if (empty)
-+                      tasklet_schedule(&tsq->tasklet);
-               local_irq_restore(flags);
-               return;
-       }