JFS: Remove COMMIT_Holdlock

The logic surrounding COMMIT_Holdlock was well-intentioned to reduce
latency when deleting files, but it can also result in a hang that I don't
have good fix for.  I don't think removing this will hurt our overall
performance very much.

fs/jfs/jfs_incore.h

@@ -116,7 +116,6 @@ enum cflags {
 	COMMIT_Inlineea,	/* commit inode inline EA */
 	COMMIT_Freewmap,	/* free WMAP at iClose() */
 	COMMIT_Dirty,		/* Inode is really dirty */
-	COMMIT_Holdlock,	/* Hold the IWRITE_LOCK until commit is done */
 	COMMIT_Dirtable,	/* commit changes to di_dirtable */
 	COMMIT_Stale,		/* data extent is no longer valid */
 	COMMIT_Synclist,	/* metadata pages on group commit synclist */

fs/jfs/jfs_txnmgr.c

@@ -1844,17 +1844,9 @@ void xtLog(struct jfs_log * log, struct tblock * tblk, struct lrd * lrd,
 		} else {
 			/*
 			 * xdlist will point to into inode's xtree, ensure
-			 * that transaction is not committed lazily unless
-			 * we're deleting the inode (unlink).  In that case
-			 * we have special logic for the inode to be
-			 * unlocked by the lazy commit thread.
+			 * that transaction is not committed lazily.
 			 */
 			xadlock->xdlist = &p->xad[XTENTRYSTART];
-			if ((tblk->xflag & COMMIT_LAZY) &&
-			    (tblk->xflag & COMMIT_DELETE) &&
-			    (tblk->ip == ip))
-				set_cflag(COMMIT_Holdlock, ip);
-			else
 			tblk->xflag &= ~COMMIT_LAZY;
 		}
 		jFYI(1,
@@ -2387,10 +2379,6 @@ static void txUpdateMap(struct tblock * tblk)
 		ip = tblk->ip;
 		diUpdatePMap(ipimap, ip->i_ino, TRUE, tblk);
 		ipimap->i_state |= I_DIRTY;
-		if (test_and_clear_cflag(COMMIT_Holdlock, ip)) {
-			if (tblk->flag & tblkGC_LAZY)
-				IWRITE_UNLOCK(ip);
-		}
 		iput(ip);
 	}
 }

fs/jfs/namei.c

@@ -544,7 +544,6 @@ int jfs_unlink(struct inode *dip, struct dentry *dentry)
 	if (ip->i_nlink == 0)
 		set_cflag(COMMIT_Nolink, ip);
 
-	if (!test_cflag(COMMIT_Holdlock, ip))
 	IWRITE_UNLOCK(ip);
 
 	/*
@@ -1256,14 +1255,6 @@ int jfs_rename(struct inode *old_dir, struct dentry *old_dentry,
 
 	rc = txCommit(tid, ipcount, iplist, commit_flag);
 
-	/*
-	 * Don't unlock new_ip if COMMIT_HOLDLOCK is set
-	 */
-	if (new_ip && test_cflag(COMMIT_Holdlock, new_ip)) {
-		up(&JFS_IP(new_ip)->commit_sem);
-		new_ip = 0;
-	}
-
       out4:
 	txEnd(tid);