NFS: Add event tracing for generic NFS events

Add tracepoints for inode attribute updates, attribute revalidation,
writeback start/end fsync start/end, attribute change start/end,
permission check start/end.

The intention is to enable performance tracing using 'perf'as well as
improving debugging.

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

1 files changed, 26 insertions, 3 deletions

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 9a98b04c4445..4bcb00ae30ae 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -51,6 +51,8 @@
 #include "nfs.h"
 #include "netns.h"
 
+#include "nfstrace.h"
+
 #define NFSDBG_FACILITY		NFSDBG_VFS
 
 #define NFS_64_BIT_INODE_NUMBERS_ENABLED	1
@@ -503,6 +505,8 @@ nfs_setattr(struct dentry *dentry, struct iattr *attr)
 	if ((attr->ia_valid & ~(ATTR_FILE|ATTR_OPEN)) == 0)
 		return 0;
 
+	trace_nfs_setattr_enter(inode);
+
 	/* Write all dirty data */
 	if (S_ISREG(inode->i_mode)) {
 		nfs_inode_dio_wait(inode);
@@ -522,6 +526,7 @@ nfs_setattr(struct dentry *dentry, struct iattr *attr)
 		error = nfs_refresh_inode(inode, fattr);
 	nfs_free_fattr(fattr);
 out:
+	trace_nfs_setattr_exit(inode, error);
 	return error;
 }
 EXPORT_SYMBOL_GPL(nfs_setattr);
@@ -591,6 +596,7 @@ int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 	int need_atime = NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATIME;
 	int err;
 
+	trace_nfs_getattr_enter(inode);
 	/* Flush out writes to the server in order to update c/mtime.  */
 	if (S_ISREG(inode->i_mode)) {
 		nfs_inode_dio_wait(inode);
@@ -621,6 +627,7 @@ int nfs_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 		stat->ino = nfs_compat_user_ino64(NFS_FILEID(inode));
 	}
 out:
+	trace_nfs_getattr_exit(inode, err);
 	return err;
 }
 EXPORT_SYMBOL_GPL(nfs_getattr);
@@ -875,6 +882,8 @@ __nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
 	dfprintk(PAGECACHE, "NFS: revalidating (%s/%Ld)\n",
 		inode->i_sb->s_id, (long long)NFS_FILEID(inode));
 
+	trace_nfs_revalidate_inode_enter(inode);
+
 	if (is_bad_inode(inode))
 		goto out;
 	if (NFS_STALE(inode))
@@ -925,6 +934,7 @@ err_out:
 	nfs4_label_free(label);
 out:
 	nfs_free_fattr(fattr);
+	trace_nfs_revalidate_inode_exit(inode, status);
 	return status;
 }
 
@@ -975,6 +985,7 @@ static int nfs_invalidate_mapping(struct inode *inode, struct address_space *map
 	spin_unlock(&inode->i_lock);
 	nfs_inc_stats(inode, NFSIOS_DATAINVALIDATE);
 	nfs_fscache_wait_on_invalidate(inode);
+
 	dfprintk(PAGECACHE, "NFS: (%s/%Ld) data cache invalidated\n",
 			inode->i_sb->s_id, (long long)NFS_FILEID(inode));
 	return 0;
@@ -1008,8 +1019,12 @@ int nfs_revalidate_mapping(struct inode *inode, struct address_space *mapping)
 		if (ret < 0)
 			goto out;
 	}
-	if (nfsi->cache_validity & NFS_INO_INVALID_DATA)
+	if (nfsi->cache_validity & NFS_INO_INVALID_DATA) {
+		trace_nfs_invalidate_mapping_enter(inode);
 		ret = nfs_invalidate_mapping(inode, mapping);
+		trace_nfs_invalidate_mapping_exit(inode, ret);
+	}
+
 out:
 	return ret;
 }
@@ -1268,9 +1283,17 @@ static int nfs_inode_attrs_need_update(const struct inode *inode, const struct n
 
 static int nfs_refresh_inode_locked(struct inode *inode, struct nfs_fattr *fattr)
 {
+	int ret;
+
+	trace_nfs_refresh_inode_enter(inode);
+
 	if (nfs_inode_attrs_need_update(inode, fattr))
-		return nfs_update_inode(inode, fattr);
-	return nfs_check_inode_attributes(inode, fattr);
+		ret = nfs_update_inode(inode, fattr);
+	else
+		ret = nfs_check_inode_attributes(inode, fattr);
+
+	trace_nfs_refresh_inode_exit(inode, ret);
+	return ret;
 }
 
 /**