Merge branch 'perf/core' into perf/uprobes

Merge in latest upstream (and the latest perf development tree),
to prepare for tooling changes, and also to pick up v3.4 MM
changes that the uprobes code needs to take care of.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 27 insertions, 20 deletions

diff --git a/fs/xfs/xfs_iget.c b/fs/xfs/xfs_iget.c
index 8c3e46394d4..bcc6c249b2c 100644
--- a/fs/xfs/xfs_iget.c
+++ b/fs/xfs/xfs_iget.c
@@ -91,7 +91,6 @@ xfs_inode_alloc(
 	ip->i_afp = NULL;
 	memset(&ip->i_df, 0, sizeof(xfs_ifork_t));
 	ip->i_flags = 0;
-	ip->i_update_core = 0;
 	ip->i_delayed_blks = 0;
 	memset(&ip->i_d, 0, sizeof(xfs_icdinode_t));
 
@@ -290,7 +289,7 @@ xfs_iget_cache_hit(
 	if (lock_flags != 0)
 		xfs_ilock(ip, lock_flags);
 
-	xfs_iflags_clear(ip, XFS_ISTALE);
+	xfs_iflags_clear(ip, XFS_ISTALE | XFS_IDONTCACHE);
 	XFS_STATS_INC(xs_ig_found);
 
 	return 0;
@@ -315,6 +314,7 @@ xfs_iget_cache_miss(
 	struct xfs_inode	*ip;
 	int			error;
 	xfs_agino_t		agino = XFS_INO_TO_AGINO(mp, ino);
+	int			iflags;
 
 	ip = xfs_inode_alloc(mp, ino);
 	if (!ip)
@@ -350,9 +350,23 @@ xfs_iget_cache_miss(
 			BUG();
 	}
 
-	spin_lock(&pag->pag_ici_lock);
+	/*
+	 * These values must be set before inserting the inode into the radix
+	 * tree as the moment it is inserted a concurrent lookup (allowed by the
+	 * RCU locking mechanism) can find it and that lookup must see that this
+	 * is an inode currently under construction (i.e. that XFS_INEW is set).
+	 * The ip->i_flags_lock that protects the XFS_INEW flag forms the
+	 * memory barrier that ensures this detection works correctly at lookup
+	 * time.
+	 */
+	iflags = XFS_INEW;
+	if (flags & XFS_IGET_DONTCACHE)
+		iflags |= XFS_IDONTCACHE;
+	ip->i_udquot = ip->i_gdquot = NULL;
+	xfs_iflags_set(ip, iflags);
 
 	/* insert the new inode */
+	spin_lock(&pag->pag_ici_lock);
 	error = radix_tree_insert(&pag->pag_ici_root, agino, ip);
 	if (unlikely(error)) {
 		WARN_ON(error != -EEXIST);
@@ -360,11 +374,6 @@ xfs_iget_cache_miss(
 		error = EAGAIN;
 		goto out_preload_end;
 	}
-
-	/* These values _must_ be set before releasing the radix tree lock! */
-	ip->i_udquot = ip->i_gdquot = NULL;
-	xfs_iflags_set(ip, XFS_INEW);
-
 	spin_unlock(&pag->pag_ici_lock);
 	radix_tree_preload_end();
 
@@ -418,6 +427,15 @@ xfs_iget(
 	xfs_perag_t	*pag;
 	xfs_agino_t	agino;
 
+	/*
+	 * xfs_reclaim_inode() uses the ILOCK to ensure an inode
+	 * doesn't get freed while it's being referenced during a
+	 * radix tree traversal here.  It assumes this function
+	 * aqcuires only the ILOCK (and therefore it has no need to
+	 * involve the IOLOCK in this synchronization).
+	 */
+	ASSERT((lock_flags & (XFS_IOLOCK_EXCL | XFS_IOLOCK_SHARED)) == 0);
+
 	/* reject inode numbers outside existing AGs */
 	if (!ino || XFS_INO_TO_AGNO(mp, ino) >= mp->m_sb.sb_agcount)
 		return EINVAL;
@@ -642,8 +660,7 @@ xfs_iunlock(
 	       (XFS_IOLOCK_SHARED | XFS_IOLOCK_EXCL));
 	ASSERT((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) !=
 	       (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL));
-	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_IUNLOCK_NONOTIFY |
-			XFS_LOCK_DEP_MASK)) == 0);
+	ASSERT((lock_flags & ~(XFS_LOCK_MASK | XFS_LOCK_DEP_MASK)) == 0);
 	ASSERT(lock_flags != 0);
 
 	if (lock_flags & XFS_IOLOCK_EXCL)
@@ -656,16 +673,6 @@ xfs_iunlock(
 	else if (lock_flags & XFS_ILOCK_SHARED)
 		mrunlock_shared(&ip->i_lock);
 
-	if ((lock_flags & (XFS_ILOCK_SHARED | XFS_ILOCK_EXCL)) &&
-	    !(lock_flags & XFS_IUNLOCK_NONOTIFY) && ip->i_itemp) {
-		/*
-		 * Let the AIL know that this item has been unlocked in case
-		 * it is in the AIL and anyone is waiting on it.  Don't do
-		 * this if the caller has asked us not to.
-		 */
-		xfs_trans_unlocked_item(ip->i_itemp->ili_item.li_ailp,
-					(xfs_log_item_t*)(ip->i_itemp));
-	}
 	trace_xfs_iunlock(ip, lock_flags, _RET_IP_);
 }