Commit 77b4d286 authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

xfs: separate primary inode selection criteria in xfs_iget_cache_hit 

During review of the v6 deferred inode inactivation patchset[1], Dave
commented that _cache_hit should have a clear separation between inode
selection criteria and actions performed on a selected inode.  Move a
hunk to make this true, and compact the shrink cases in the function.

[1] https://lore.kernel.org/linux-xfs/162310469340.3465262.504398465311182657.stgit@locust/T/#mca6d958521cb88bbc1bfe1a30767203328d410b5


Signed-off-by: default avatarDarrick J. Wong <djwong@kernel.org>
Reviewed-by: default avatarBrian Foster <bfoster@redhat.com>
parent ff7bebeb

fs/xfs/xfs_icache.c

+16 −23
Original line number Diff line number Diff line
@@ -507,13 +507,8 @@ xfs_iget_cache_hit( 
	 * will not match, so check for that, too.

	 */

	spin_lock(&ip->i_flags_lock);

	if (ip->i_ino != ino) {

		trace_xfs_iget_skip(ip);

		XFS_STATS_INC(mp, xs_ig_frecycle);

		error = -EAGAIN;

		goto out_error;

	}



	if (ip->i_ino != ino)

		goto out_skip;



	/*

	 * If we are racing with another cache hit that is currently
@@ -525,12 +520,8 @@ xfs_iget_cache_hit( 
	 *	     wait_on_inode to wait for these flags to be cleared

	 *	     instead of polling for it.

	 */

	if (ip->i_flags & (XFS_INEW|XFS_IRECLAIM)) {

		trace_xfs_iget_skip(ip);

		XFS_STATS_INC(mp, xs_ig_frecycle);

		error = -EAGAIN;

		goto out_error;

	}

	if (ip->i_flags & (XFS_INEW | XFS_IRECLAIM))

		goto out_skip;



	/*

	 * Check the inode free state is valid. This also detects lookup
@@ -540,23 +531,21 @@ xfs_iget_cache_hit( 
	if (error)

		goto out_error;



	if (ip->i_flags & XFS_IRECLAIMABLE) {

		if (flags & XFS_IGET_INCORE) {

			error = -EAGAIN;

			goto out_error;

		}

	/* Skip inodes that have no vfs state. */

	if ((flags & XFS_IGET_INCORE) &&

	    (ip->i_flags & XFS_IRECLAIMABLE))

		goto out_skip;



	/* The inode fits the selection criteria; process it. */

	if (ip->i_flags & XFS_IRECLAIMABLE) {

		/* Drops i_flags_lock and RCU read lock. */

		error = xfs_iget_recycle(pag, ip);

		if (error)

			return error;

	} else {

		/* If the VFS inode is being torn down, pause and try again. */

		if (!igrab(inode)) {

			trace_xfs_iget_skip(ip);

			error = -EAGAIN;

			goto out_error;

		}

		if (!igrab(inode))

			goto out_skip;



		/* We've got a live one. */

		spin_unlock(&ip->i_flags_lock);
@@ -573,6 +562,10 @@ xfs_iget_cache_hit( 


	return 0;



out_skip:

	trace_xfs_iget_skip(ip);

	XFS_STATS_INC(mp, xs_ig_frecycle);

	error = -EAGAIN;

out_error:

	spin_unlock(&ip->i_flags_lock);

	rcu_read_unlock();