[Xen-devel] [PATCH] linux: Adjust memory allocation condition in netback

["Jan Beulich" <jbeulich@xxxxxxxxxx>]

.. to reduce memory pressure on Xen and avoid unnecessarily stalling
receives.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxxxx>

Index: head-2007-02-27/drivers/xen/netback/netback.c
===================================================================
--- head-2007-02-27.orig/drivers/xen/netback/netback.c  2007-03-01 
15:23:00.000000000 +0100
+++ head-2007-02-27/drivers/xen/netback/netback.c       2007-03-12 
09:26:17.000000000 +0100
@@ -110,6 +110,7 @@ static unsigned int alloc_index = 0;
 
 static inline unsigned long alloc_mfn(void)
 {
+       BUG_ON(!alloc_index);
        return mfn_list[--alloc_index];
 }
 
@@ -552,6 +553,7 @@ static void net_rx_action(unsigned long 
                *(int *)skb->cb = nr_frags;
 
                if (!xen_feature(XENFEAT_auto_translated_physmap) &&
+                   !((netif_t *)netdev_priv(skb->dev))->copying_receiver &&
                    check_mfn(nr_frags + 1)) {
                        /* Memory squeeze? Back off for an arbitrary while. */
                        if ( net_ratelimit() )



_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel