From 78b1f6070fa16cb442a7c48e8f5364cd84a88b90 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Thu, 23 Apr 2009 11:20:29 +0000 Subject: [PATCH] igb: always use adapter->itr as EITR value The igb driver was switching between adapter->itr containing the EITR value and the number of interrupts per second. This resulted in high latencies being seen after brining the interface down and then back up. To resolve the issue the itr value will now only contain the value that should be programmed into EITR. Signed-off-by: Alexander Duyck Signed-off-by: Jeff Kirsher Signed-off-by: David S. Miller --- drivers/net/igb/igb_main.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/net/igb/igb_main.c b/drivers/net/igb/igb_main.c index 183235d46aee..ab846ec65204 100644 --- a/drivers/net/igb/igb_main.c +++ b/drivers/net/igb/igb_main.c @@ -2898,13 +2898,13 @@ static void igb_set_itr(struct igb_adapter *adapter) switch (current_itr) { /* counts and packets in update_itr are dependent on these numbers */ case lowest_latency: - new_itr = 70000; + new_itr = 56; /* aka 70,000 ints/sec */ break; case low_latency: - new_itr = 20000; /* aka hwitr = ~200 */ + new_itr = 196; /* aka 20,000 ints/sec */ break; case bulk_latency: - new_itr = 4000; + new_itr = 980; /* aka 4,000 ints/sec */ break; default: break; @@ -2923,7 +2923,8 @@ set_itr_now: * by adding intermediate steps when interrupt rate is * increasing */ new_itr = new_itr > adapter->itr ? - min(adapter->itr + (new_itr >> 2), new_itr) : + max((new_itr * adapter->itr) / + (new_itr + (adapter->itr >> 2)), new_itr) : new_itr; /* Don't write the value here; it resets the adapter's * internal timer, and causes us to delay far longer than @@ -2932,7 +2933,7 @@ set_itr_now: * ends up being correct. */ adapter->itr = new_itr; - adapter->rx_ring->itr_val = 1000000000 / (new_itr * 256); + adapter->rx_ring->itr_val = new_itr; adapter->rx_ring->set_itr = 1; }