Imported linux-2.6.27.39 suse/xen patches.

[people/pmueller/ipfire-2.x.git] / src / patches / suse-2.6.27.31 / patches.xen / 849-sfc-tx-skb-lock.patch

diff --git a/src/patches/suse-2.6.27.31/patches.xen/849-sfc-tx-skb-lock.patch b/src/patches/suse-2.6.27.31/patches.xen/849-sfc-tx-skb-lock.patch
deleted file mode 100644 (file)
index 74f6647..0000000
--- a/src/patches/suse-2.6.27.31/patches.xen/849-sfc-tx-skb-lock.patch
+++ /dev/null
@@ -1,113 +0,0 @@
-From: http://xenbits.xensource.com/linux-2.6.18-xen.hg?rev/3a4410c4504e
-# HG changeset 849 patch
-# User Keir Fraser <keir.fraser@citrix.com>
-# Date 1238497253 -3600
-# Node ID 3a4410c4504ea64f2c1e873df3234938366050ad
-# Parent  ab1d4fbbe4bf93f203e0c4d62c18bd248e4f1d4a
-Subject: sfc_netfront: Only clear tx_skb when ready for netif_wake_queue
-(doing otherwise could result in a lost packet) and document use of
-locks to protect tx_skb
-References: bnc#489721
-Patch-mainline: obsolete
-
-Signed-off-by: Kieran Mansley <kmansley@solarflare.com>
-Acked-by: jbeulich@novell.com
-
---- sle11-2009-04-09.orig/drivers/xen/sfc_netfront/accel.h     2009-04-09 14:23:18.000000000 +0200
-+++ sle11-2009-04-09/drivers/xen/sfc_netfront/accel.h  2009-04-09 14:41:38.000000000 +0200
-@@ -261,8 +261,10 @@ typedef struct netfront_accel_vnic {
- 
-       int poll_enabled;
- 
--      /** A spare slot for a TX packet.  This is treated as an extension
--       * of the DMA queue. */
-+      /** A spare slot for a TX packet.  This is treated as an
-+       * extension of the DMA queue.  Reads require either
-+       * netfront's tx_lock or the vnic tx_lock; writes require both
-+       * locks */
-       struct sk_buff *tx_skb;
- 
-       /** Keep track of fragments of SSR packets */
---- sle11-2009-04-09.orig/drivers/xen/sfc_netfront/accel_netfront.c    2009-03-30 16:16:28.000000000 +0200
-+++ sle11-2009-04-09/drivers/xen/sfc_netfront/accel_netfront.c 2009-04-09 14:42:13.000000000 +0200
-@@ -65,7 +65,7 @@ static int netfront_accel_netdev_start_x
-               BUG_ON(vnic->net_dev != net_dev);
-               DPRINTK("%s stopping queue\n", __FUNCTION__);
- 
--              /* Netfront's lock protects tx_skb */
-+              /* Need netfront's tx_lock and vnic tx_lock to write tx_skb */
-               spin_lock_irqsave(&np->tx_lock, flags2);
-               BUG_ON(vnic->tx_skb != NULL);
-               vnic->tx_skb = skb;
-@@ -183,7 +183,7 @@ static int netfront_accel_check_ready(st
- 
-       BUG_ON(vnic == NULL);
- 
--      /* This is protected by netfront's lock */ 
-+      /* Read of tx_skb is protected by netfront's tx_lock */
-       return vnic->tx_skb == NULL;
- }
- 
---- sle11-2009-04-09.orig/drivers/xen/sfc_netfront/accel_vi.c  2009-04-09 14:23:18.000000000 +0200
-+++ sle11-2009-04-09/drivers/xen/sfc_netfront/accel_vi.c       2009-04-09 14:41:38.000000000 +0200
-@@ -980,39 +980,35 @@ static void netfront_accel_vi_not_busy(n
- {
-       struct netfront_info *np = ((struct netfront_info *)
-                                   netdev_priv(vnic->net_dev));
--      struct sk_buff *skb;
-       int handled;
-       unsigned long flags;
--      
-+
-       /*
--       * TODO if we could safely check tx_skb == NULL and return
--       * early without taking the lock, that would obviously help
--       * performance
-+       * We hold the vnic tx_lock which is sufficient to exclude
-+       * writes to tx_skb
-        */
- 
--      /* Take the netfront lock which protects tx_skb. */
--      spin_lock_irqsave(&np->tx_lock, flags);
-       if (vnic->tx_skb != NULL) {
-               DPRINTK("%s trying to send spare buffer\n", __FUNCTION__);
-               
--              skb = vnic->tx_skb;
--              vnic->tx_skb = NULL;
--
--              spin_unlock_irqrestore(&np->tx_lock, flags);
--
--              handled = netfront_accel_vi_tx_post(vnic, skb);
-+              handled = netfront_accel_vi_tx_post(vnic, vnic->tx_skb);
-               
--              spin_lock_irqsave(&np->tx_lock, flags);
--
-               if (handled != NETFRONT_ACCEL_STATUS_BUSY) {
-                       DPRINTK("%s restarting tx\n", __FUNCTION__);
-+
-+                      /* Need netfront tx_lock and vnic tx_lock to
-+                       * write tx_skb */
-+                      spin_lock_irqsave(&np->tx_lock, flags);
-+
-+                      vnic->tx_skb = NULL;
-+
-                       if (netfront_check_queue_ready(vnic->net_dev)) {
-                               netif_wake_queue(vnic->net_dev);
-                               NETFRONT_ACCEL_STATS_OP
-                                       (vnic->stats.queue_wakes++);
-                       }
--              } else {
--                      vnic->tx_skb = skb;
-+                      spin_unlock_irqrestore(&np->tx_lock, flags);
-+
-               }
-               
-               /*
-@@ -1021,7 +1017,6 @@ static void netfront_accel_vi_not_busy(n
-                */
-               BUG_ON(handled == NETFRONT_ACCEL_STATUS_CANT);
-       }
--      spin_unlock_irqrestore(&np->tx_lock, flags);
- }
- 
-