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Subject[PATCH] net: revert default NAPI poll timeout to 2 jiffies
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For HZ < 1000 timeout 2000us rounds up to 1 jiffy but expires randomly
because next timer interrupt could come shortly after starting softirq.

For commonly used CONFIG_HZ=1000 nothing changes.

Fixes: 7acf8a1e8a28 ("Replace 2 jiffies with sysctl netdev_budget_usecs to enable softirq tuning")
Reported-by: Dmitry Yakunin <zeil@yandex-team.ru>
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
---
net/core/dev.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/core/dev.c b/net/core/dev.c
index 9c9e763bfe0e..df8097b8e286 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4140,7 +4140,8 @@ EXPORT_SYMBOL(netdev_max_backlog);

int netdev_tstamp_prequeue __read_mostly = 1;
int netdev_budget __read_mostly = 300;
-unsigned int __read_mostly netdev_budget_usecs = 2000;
+/* Must be at least 2 jiffes to guarantee 1 jiffy timeout */
+unsigned int __read_mostly netdev_budget_usecs = 2 * USEC_PER_SEC / HZ;
int weight_p __read_mostly = 64; /* old backlog weight */
int dev_weight_rx_bias __read_mostly = 1; /* bias for backlog weight */
int dev_weight_tx_bias __read_mostly = 1; /* bias for output_queue quota */
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