From cde46035161d677617983177e877c87d89fbb5e1 Mon Sep 17 00:00:00 2001
From: Frank Blaschka <frank.blaschka@de.ibm.com>
Date: Wed, 29 Aug 2007 11:26:53 +0200
Subject: qeth: enforce a rate limit for inbound scatter gather messages

under memory pressure scatter gather mode switching messages must be
rate limited.

Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

diff --git a/drivers/s390/net/qeth_main.c b/drivers/s390/net/qeth_main.c
index ba10d42..610d27c 100644
--- a/drivers/s390/net/qeth_main.c
+++ b/drivers/s390/net/qeth_main.c
@@ -2803,13 +2803,16 @@ qeth_queue_input_buffer(struct qeth_card *card, int index)
 		if (newcount < count) {
 			/* we are in memory shortage so we switch back to
 			   traditional skb allocation and drop packages */
-			if (atomic_cmpxchg(&card->force_alloc_skb, 0, 1))
-				printk(KERN_WARNING
-					"qeth: switch to alloc skb\n");
+			if (!atomic_read(&card->force_alloc_skb) &&
+			    net_ratelimit())
+				PRINT_WARN("Switch to alloc skb\n");
+			atomic_set(&card->force_alloc_skb, 3);
 			count = newcount;
 		} else {
-			if (atomic_cmpxchg(&card->force_alloc_skb, 1, 0))
-				printk(KERN_WARNING "qeth: switch to sg\n");
+			if ((atomic_read(&card->force_alloc_skb) == 1) &&
+			    net_ratelimit())
+				PRINT_WARN("Switch to sg\n");
+			atomic_add_unless(&card->force_alloc_skb, -1, 0);
 		}
 
 		/*
-- 
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