NFS: add I/O performance counters

Invoke the byte and event counter macros where we want to count bytes and
events.

Clean-up: fix a possible NULL dereference in nfs_lock, and simplify
nfs_file_open.

Test-plan:
fsx and iozone on UP and SMP systems, with and without pre-emption.  Watch
for memory overwrite bugs, and performance loss (significantly more CPU
required per op).

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 86b756f44e27..8ee74111e519 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -753,6 +753,8 @@ static void nfs_zap_caches_locked(struct inode *inode)
         struct nfs_inode *nfsi = NFS_I(inode);
         int mode = inode->i_mode;
 
+        nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
+
         NFS_ATTRTIMEO(inode) = NFS_MINATTRTIMEO(inode);
         NFS_ATTRTIMEO_UPDATE(inode) = jiffies;
 
@@ -940,6 +942,8 @@ nfs_setattr(struct dentry *dentry, struct iattr *attr)
         struct nfs_fattr fattr;
         int error;
 
+        nfs_inc_stats(inode, NFSIOS_VFSSETATTR);
+
         if (attr->ia_valid & ATTR_SIZE) {
                 if (!S_ISREG(inode->i_mode) || attr->ia_size == i_size_read(inode))
                         attr->ia_valid &= ~ATTR_SIZE;
@@ -993,6 +997,7 @@ void nfs_setattr_update_inode(struct inode *inode, struct iattr *attr)
                 spin_unlock(&inode->i_lock);
         }
         if ((attr->ia_valid & ATTR_SIZE) != 0) {
+                nfs_inc_stats(inode, NFSIOS_SETATTRTRUNC);
                 inode->i_size = attr->ia_size;
                 vmtruncate(inode, attr->ia_size);
         }
@@ -1278,6 +1283,7 @@ int nfs_attribute_timeout(struct inode *inode)
  */
 int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
 {
+        nfs_inc_stats(inode, NFSIOS_INODEREVALIDATE);
         if (!(NFS_I(inode)->cache_validity & (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA))
                         && !nfs_attribute_timeout(inode))
                 return NFS_STALE(inode) ? -ESTALE : 0;
@@ -1294,6 +1300,7 @@ void nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
         struct nfs_inode *nfsi = NFS_I(inode);
 
         if (nfsi->cache_validity & NFS_INO_INVALID_DATA) {
+                nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
                 if (S_ISREG(inode->i_mode))
                         nfs_sync_mapping(mapping);
                 invalidate_inode_pages2(mapping);
@@ -1615,6 +1622,7 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 
         /* Update attrtimeo value if we're out of the unstable period */
         if (invalid & NFS_INO_INVALID_ATTR) {
+                nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
                 nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
                 nfsi->attrtimeo_timestamp = jiffies;
         } else if (time_after(jiffies, nfsi->attrtimeo_timestamp+nfsi->attrtimeo)) {