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: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 449df8c8..b7d4f8f 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -785,7 +785,8 @@
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 @@
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 @@
}
/**
- * 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 @@
* 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 @@
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 @@
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 @@
if (!nfs_have_delegation(inode, FMODE_READ))
nfsi->cache_validity |= invalid;
- spin_unlock(&inode->i_lock);
return 0;
out_changed:
/*
diff --git a/fs/nfs/nfs2xdr.c b/fs/nfs/nfs2xdr.c
index d91b690..59049e8 100644
--- a/fs/nfs/nfs2xdr.c
+++ b/fs/nfs/nfs2xdr.c
@@ -143,7 +143,6 @@
fattr->mode = (fattr->mode & ~S_IFMT) | S_IFIFO;
fattr->rdev = 0;
}
- fattr->timestamp = jiffies;
return p;
}
diff --git a/fs/nfs/nfs3xdr.c b/fs/nfs/nfs3xdr.c
index db4a904..0498bd3 100644
--- a/fs/nfs/nfs3xdr.c
+++ b/fs/nfs/nfs3xdr.c
@@ -174,7 +174,6 @@
/* Update the mode bits */
fattr->valid |= (NFS_ATTR_FATTR | NFS_ATTR_FATTR_V3);
- fattr->timestamp = jiffies;
return p;
}
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index cd76264..8b21de8 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -2799,10 +2799,8 @@
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);
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index abf890f..faeaad6 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -141,6 +141,7 @@
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 @@
static inline void nfs_fattr_init(struct nfs_fattr *fattr)
{
fattr->valid = 0;
+ fattr->time_start = jiffies;
}
/*
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 60086da..aeaee7e 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -41,7 +41,7 @@
__u32 bitmap[2]; /* NFSv4 returned attribute bitmap */
__u64 change_attr; /* NFSv4 change attribute */
__u64 pre_change_attr;/* pre-op NFSv4 change attribute */
- unsigned long timestamp;
+ unsigned long time_start;
};
#define NFS_ATTR_WCC 0x0001 /* pre-op WCC data */
