[Ocfs2-commits] zab commits r1918 - trunk/fs/ocfs2

[svn-commits at oss.oracle.com]

Author: zab
Signed-off-by: mfasheh
Date: 2005-02-28 16:26:34 -0600 (Mon, 28 Feb 2005)
New Revision: 1918

Modified:
   trunk/fs/ocfs2/dlmglue.c
Log:
o handle multiple BAST arrival by only asking the vote thread for a down
  convert if previously issued ones weren't low enough 

Signed-off-by: mfasheh


Modified: trunk/fs/ocfs2/dlmglue.c
===================================================================
--- trunk/fs/ocfs2/dlmglue.c	2005-02-28 21:53:11 UTC (rev 1917)
+++ trunk/fs/ocfs2/dlmglue.c	2005-02-28 22:26:34 UTC (rev 1918)
@@ -181,7 +181,7 @@
 static inline void ocfs2_generic_handle_downconvert_action(ocfs2_lock_res *lockres);
 static inline void ocfs2_generic_handle_convert_action(ocfs2_lock_res *lockres);
 static inline void ocfs2_generic_handle_attach_action(ocfs2_lock_res *lockres);
-static void ocfs2_generic_handle_bast(ocfs2_lock_res *lockres, int level);
+static int ocfs2_generic_handle_bast(ocfs2_lock_res *lockres, int level);
 static inline void ocfs2_handle_meta_convert_action(struct inode *inode,
 						    ocfs2_lock_res *lockres);
 static void ocfs2_inc_inode_seq(ocfs_super *osb,
@@ -615,17 +615,29 @@
 	LOG_EXIT();
 }
 
-static void ocfs2_generic_handle_bast(ocfs2_lock_res *lockres, int level)
+static int ocfs2_generic_handle_bast(ocfs2_lock_res *lockres, int level)
 {
+	int needs_downconvert = 0;
 	LOG_ENTRY();
 
-	spin_lock(&lockres->l_lock);
+	assert_spin_locked(&lockres->l_lock);
+
 	lockres->l_flags |= OCFS2_LOCK_BLOCKED;
-	if (level > lockres->l_blocking)
+
+	if (level > lockres->l_blocking) {
+		/* only schedule a downconvert if we haven't already scheduled
+		 * one that goes low enough to satisfy the level we're 
+		 * blocking.  this also catches the case where we get 
+		 * duplicate BASTs */
+		if (ocfs2_highest_compat_lock_level(level) <
+		    ocfs2_highest_compat_lock_level(lockres->l_blocking))
+			needs_downconvert = 1;
+
 		lockres->l_blocking = level;
-	spin_unlock(&lockres->l_lock);
+	}
 
-	LOG_EXIT();
+	LOG_EXIT_STATUS(needs_downconvert);
+	return needs_downconvert;
 }
 
 static void ocfs2_inode_bast_func(void *opaque, int level)
@@ -633,6 +645,7 @@
 	ocfs2_lock_res *lockres = opaque;
 	struct inode *inode;
 	ocfs_super *osb;
+	int needs_downconvert;
 
 	LOG_ENTRY();
 
@@ -646,13 +659,18 @@
 
 	OCFS_ASSERT(level > LKM_NLMODE);
 
-	ocfs2_generic_handle_bast(lockres, level);
+	spin_lock(&lockres->l_lock);
 
-	ocfs2_schedule_blocked_inode_lock(inode, lockres);
+	needs_downconvert = ocfs2_generic_handle_bast(lockres, level);
+	if (needs_downconvert)
+		ocfs2_schedule_blocked_inode_lock(inode, lockres);
+
+	spin_unlock(&lockres->l_lock);
+
 	ocfs2_kick_vote_thread(osb);
-
 	/* TODO: Is a wake_up call here really necessary? */
 	wake_up(&lockres->l_event);
+
 	LOG_EXIT();
 }
 
@@ -701,15 +719,19 @@
 {
 	ocfs2_lock_res *lockres = opaque;
 	ocfs_super *osb;
+	int needs_downconvert;
 
 	LOG_ENTRY();
        	osb = ocfs2_lock_res_super(lockres);
 
 	dprintk("Superblock BAST fired\n");
 
-	ocfs2_generic_handle_bast(lockres, level);
+	spin_lock(&lockres->l_lock);
+	needs_downconvert = ocfs2_generic_handle_bast(lockres, level);
+	if (needs_downconvert)
+		ocfs2_schedule_blocked_lock(osb, lockres);
+	spin_unlock(&lockres->l_lock);
 
-	ocfs2_schedule_blocked_lock(osb, lockres);
 	ocfs2_kick_vote_thread(osb);
 
 	wake_up(&lockres->l_event);