Commit 33801147 authored by Trond Myklebust's avatar Trond Myklebust
Browse files

NFS: Optimise inode attribute cache updates 



 Allow nfs_refresh_inode() also to update attributes on the inode if the
 RPC call was sent after the last call to nfs_update_inode().

 Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent 913a70fc

fs/nfs/inode.c

+40 −14
Original line number Diff line number Diff line
@@ -785,7 +785,8 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr) 
		else

			init_special_inode(inode, inode->i_mode, fattr->rdev);



		nfsi->read_cache_jiffies = fattr->timestamp;

		nfsi->read_cache_jiffies = fattr->time_start;

		nfsi->last_updated = jiffies;

		inode->i_atime = fattr->atime;

		inode->i_mtime = fattr->mtime;

		inode->i_ctime = fattr->ctime;
@@ -1120,14 +1121,15 @@ __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode) 
		goto out;

	}



	spin_lock(&inode->i_lock);

	status = nfs_update_inode(inode, &fattr, verifier);

	if (status) {

		spin_unlock(&inode->i_lock);

		dfprintk(PAGECACHE, "nfs_revalidate_inode: (%s/%Ld) refresh failed, error=%d\n",

			 inode->i_sb->s_id,

			 (long long)NFS_FILEID(inode), status);

		goto out;

	}

	spin_lock(&inode->i_lock);

	cache_validity = nfsi->cache_validity;

	nfsi->cache_validity &= ~NFS_INO_REVAL_PAGECACHE;
@@ -1247,7 +1249,7 @@ void nfs_end_data_update(struct inode *inode) 
}



/**

 * nfs_refresh_inode - verify consistency of the inode attribute cache

 * nfs_check_inode_attributes - verify consistency of the inode attribute cache

 * @inode - pointer to inode

 * @fattr - updated attributes

 *
@@ -1255,13 +1257,12 @@ void nfs_end_data_update(struct inode *inode) 
 * so that fattr carries weak cache consistency data, then it may

 * also update the ctime/mtime/change_attribute.

 */

int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)

static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fattr)

{

	struct nfs_inode *nfsi = NFS_I(inode);

	loff_t cur_size, new_isize;

	int data_unstable;



	spin_lock(&inode->i_lock);



	/* Are we in the process of updating data on the server? */

	data_unstable = nfs_caches_unstable(inode);
@@ -1325,11 +1326,40 @@ int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr) 
	if (!timespec_equal(&inode->i_atime, &fattr->atime))

		nfsi->cache_validity |= NFS_INO_INVALID_ATIME;



	nfsi->read_cache_jiffies = fattr->timestamp;

	spin_unlock(&inode->i_lock);

	nfsi->read_cache_jiffies = fattr->time_start;

	return 0;

}



/**

 * nfs_refresh_inode - try to update the inode attribute cache

 * @inode - pointer to inode

 * @fattr - updated attributes

 *

 * Check that an RPC call that returned attributes has not overlapped with

 * other recent updates of the inode metadata, then decide whether it is

 * safe to do a full update of the inode attributes, or whether just to

 * call nfs_check_inode_attributes.

 */

int nfs_refresh_inode(struct inode *inode, struct nfs_fattr *fattr)

{

	struct nfs_inode *nfsi = NFS_I(inode);

	int status;



	if ((fattr->valid & NFS_ATTR_FATTR) == 0)

		return 0;

	spin_lock(&inode->i_lock);

	nfsi->cache_validity &= ~NFS_INO_REVAL_PAGECACHE;

	if (nfs_verify_change_attribute(inode, fattr->time_start))

		nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ATIME);

	if (time_after(fattr->time_start, nfsi->last_updated))

		status = nfs_update_inode(inode, fattr, fattr->time_start);

	else

		status = nfs_check_inode_attributes(inode, fattr);



	spin_unlock(&inode->i_lock);

	return status;

}



/*

 * Many nfs protocol calls return the new file attributes after

 * an operation.  Here we update the inode to reflect the state
@@ -1365,20 +1395,17 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr, unsign 
		goto out_err;

	}



	spin_lock(&inode->i_lock);



	/*

	 * Make sure the inode's type hasn't changed.

	 */

	if ((inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT)) {

		spin_unlock(&inode->i_lock);

	if ((inode->i_mode & S_IFMT) != (fattr->mode & S_IFMT))

		goto out_changed;

	}



	/*

	 * Update the read time so we don't revalidate too often.

	 */

	nfsi->read_cache_jiffies = fattr->timestamp;

	nfsi->read_cache_jiffies = fattr->time_start;

	nfsi->last_updated = jiffies;



	/* Are we racing with known updates of the metadata on the server? */

	data_unstable = ! (nfs_verify_change_attribute(inode, verifier) ||
@@ -1467,7 +1494,6 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr, unsign 
	if (!nfs_have_delegation(inode, FMODE_READ))

		nfsi->cache_validity |= invalid;



	spin_unlock(&inode->i_lock);

	return 0;

 out_changed:

	/*

fs/nfs/nfs2xdr.c

+0 −1
Original line number Diff line number Diff line
@@ -143,7 +143,6 @@ xdr_decode_fattr(u32 *p, struct nfs_fattr *fattr) 
		fattr->mode = (fattr->mode & ~S_IFMT) | S_IFIFO;

		fattr->rdev = 0;

	}

	fattr->timestamp = jiffies;

	return p;

}

fs/nfs/nfs3xdr.c

+0 −1
Original line number Diff line number Diff line
@@ -174,7 +174,6 @@ xdr_decode_fattr(u32 *p, struct nfs_fattr *fattr) 


	/* Update the mode bits */

	fattr->valid |= (NFS_ATTR_FATTR | NFS_ATTR_FATTR_V3);

	fattr->timestamp = jiffies;

	return p;

}

fs/nfs/nfs4xdr.c

+1 −3
Original line number Diff line number Diff line
@@ -2799,10 +2799,8 @@ static int decode_getfattr(struct xdr_stream *xdr, struct nfs_fattr *fattr, cons 
		goto xdr_error;

	if ((status = decode_attr_time_modify(xdr, bitmap, &fattr->mtime)) != 0)

		goto xdr_error;

	if ((status = verify_attr_len(xdr, savep, attrlen)) == 0) {

	if ((status = verify_attr_len(xdr, savep, attrlen)) == 0)

		fattr->valid = NFS_ATTR_FATTR | NFS_ATTR_FATTR_V3 | NFS_ATTR_FATTR_V4;

		fattr->timestamp = jiffies;

	}

xdr_error:

	if (status != 0)

		printk(KERN_NOTICE "%s: xdr error %d!\n", __FUNCTION__, -status);

include/linux/nfs_fs.h

+2 −0
Original line number Diff line number Diff line
@@ -141,6 +141,7 @@ struct nfs_inode { 
	unsigned long		attrtimeo_timestamp;

	__u64			change_attr;		/* v4 only */



	unsigned long		last_updated;

	/* "Generation counter" for the attribute cache. This is

	 * bumped whenever we update the metadata on the

	 * server.
@@ -319,6 +320,7 @@ extern u32 root_nfs_parse_addr(char *name); /*__init*/ 
static inline void nfs_fattr_init(struct nfs_fattr *fattr)

{

	fattr->valid = 0;

	fattr->time_start = jiffies;

}



/*