[v2.6.34-stable 057/213] net: reduce net_rx_action() latency to 2 HZ

From: Paul Gortmaker
Date: Wed Feb 05 2014 - 16:00:31 EST


From: Eric Dumazet <edumazt@xxxxxxxxxx>

-------------------
This is a commit scheduled for the next v2.6.34 longterm release.
http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git
If you see a problem with using this for longterm, please comment.
-------------------

commit d1f41b67ff7735193bc8b418b98ac99a448833e2 upstream.

We should use time_after_eq() to get maximum latency of two ticks,
instead of three.

Bug added in commit 24f8b2385 (net: increase receive packet quantum)

Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
---
net/core/dev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/dev.c b/net/core/dev.c
index 2aaf2e610f92..253b409fe3ab 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3045,7 +3045,7 @@ static void net_rx_action(struct softirq_action *h)
* Allow this to run for 2 jiffies since which will allow
* an average latency of 1.5/HZ.
*/
- if (unlikely(budget <= 0 || time_after(jiffies, time_limit)))
+ if (unlikely(budget <= 0 || time_after_eq(jiffies, time_limit)))
goto softnet_break;

local_irq_enable();
--
1.8.5.2

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