fscache: Add tracepoints

Add some tracepoints to fscache:

 (*) fscache_cookie - Tracks a cookie's usage count.

 (*) fscache_netfs - Logs registration of a network filesystem, including
     the pointer to the cookie allocated.

 (*) fscache_acquire - Logs cookie acquisition.

 (*) fscache_relinquish - Logs cookie relinquishment.

 (*) fscache_enable - Logs enablement of a cookie.

 (*) fscache_disable - Logs disablement of a cookie.

 (*) fscache_osm - Tracks execution of states in the object state machine.

and cachefiles:

 (*) cachefiles_ref - Tracks a cachefiles object's usage count.

 (*) cachefiles_lookup - Logs result of lookup_one_len().

 (*) cachefiles_mkdir - Logs result of vfs_mkdir().

 (*) cachefiles_create - Logs result of vfs_create().

 (*) cachefiles_unlink - Logs calls to vfs_unlink().

 (*) cachefiles_rename - Logs calls to vfs_rename().

 (*) cachefiles_mark_active - Logs an object becoming active.

 (*) cachefiles_wait_active - Logs a wait for an old object to be
     destroyed.

 (*) cachefiles_mark_inactive - Logs an object becoming inactive.

 (*) cachefiles_mark_buried - Logs the burial of an object.

Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/fscache/netfs.c b/fs/fscache/netfs.c
index a8aa00be4444..c816600d1dde 100644
--- a/fs/fscache/netfs.c
+++ b/fs/fscache/netfs.c
@@ -60,7 +60,7 @@ int __fscache_register_netfs(struct fscache_netfs *netfs)
 			goto already_registered;
 	}
 
-	atomic_inc(&cookie->parent->usage);
+	fscache_cookie_get(cookie->parent, fscache_cookie_get_register_netfs);
 	atomic_inc(&cookie->parent->n_children);
 
 	netfs->primary_index = cookie;
@@ -68,6 +68,7 @@ int __fscache_register_netfs(struct fscache_netfs *netfs)
 	ret = 0;
 
 	pr_notice("Netfs '%s' registered for caching\n", netfs->name);
+	trace_fscache_netfs(netfs);
 
 already_registered:
 	up_write(&fscache_addremove_sem);