From c9fb82a6a21b51c4f72a907a447194fc0e57a806 Mon Sep 17 00:00:00 2001
From: Owen Smith <owen.smith@citrix.com>
Date: Fri, 7 Feb 2014 10:55:00 +0000
Subject: [PATCH] Reduce calls to BlockRingPush and NotifierSend during
 PdoSubmitPrepared Remove ListContains assertions

Signed-off-by: Owen Smith <owen.smith@citrix.com>
---
 src/xenvbd/pdo.c   |  6 +++---
 src/xenvbd/queue.c | 24 ------------------------
 2 files changed, 3 insertions(+), 27 deletions(-)

diff --git a/src/xenvbd/pdo.c b/src/xenvbd/pdo.c
index 326748e..30afe35 100644
--- a/src/xenvbd/pdo.c
+++ b/src/xenvbd/pdo.c
@@ -1235,10 +1235,10 @@ PdoSubmitPrepared(
 
         QueueAppend(&Pdo->SubmittedReqs, &Request->Entry);
         Request->Srb->SrbStatus = SRB_STATUS_SUCCESS;
+    }
 
-        if (BlockRingPush(BlockRing)) {
-            NotifierSend(Notifier);
-        }
+    if (BlockRingPush(BlockRing)) {
+        NotifierSend(Notifier);
     }
 }
 
diff --git a/src/xenvbd/queue.c b/src/xenvbd/queue.c
index 4cf3eed..9616489 100644
--- a/src/xenvbd/queue.c
+++ b/src/xenvbd/queue.c
@@ -51,27 +51,6 @@ QueueCount(
     return Queue->Current;
 }
 
-static FORCEINLINE BOOLEAN
-__ListContains(
-    IN  PLIST_ENTRY         Head,
-    IN  PLIST_ENTRY         List
-    )
-{
-    PLIST_ENTRY Entry;
-
-    for (Entry = Head->Flink;
-            Entry != Head;
-            Entry = Entry->Flink)
-    {
-        if (Entry == List)
-            return TRUE;
-    }
-
-    return FALSE;
-}
-
-#define ListContains(_h, _l)    __ListContains(_h, _l)
-
 __checkReturn
 PLIST_ENTRY
 QueuePop(
@@ -104,7 +83,6 @@ QueueUnPop(
 
     KeAcquireSpinLock(&Queue->Lock, &Irql);
     
-    ASSERT(!ListContains(&Queue->List, Entry));
     InsertHeadList(&Queue->List, Entry);
     if (++Queue->Current > Queue->Maximum)
         Queue->Maximum = Queue->Current;
@@ -122,7 +100,6 @@ QueueAppend(
 
     KeAcquireSpinLock(&Queue->Lock, &Irql);
     
-    ASSERT(!ListContains(&Queue->List, Entry));
     InsertTailList(&Queue->List, Entry);
     if (++Queue->Current > Queue->Maximum)
         Queue->Maximum = Queue->Current;
@@ -140,7 +117,6 @@ QueueRemove(
 
     KeAcquireSpinLock(&Queue->Lock, &Irql);
 
-    ASSERT(ListContains(&Queue->List, Entry));
     RemoveEntryList(Entry);
     --Queue->Current;
     
-- 
2.39.5