afs: Add some callback management tracepoints
Add a couple of tracepoints to track callback management:
(1) afs_cb_miss - Logs when we were unable to apply a callback, either due
to the inode being discarded or due to a competing thread applying a
callback first.
(2) afs_cb_break - Logs when we attempted to clear the noted callback
promise, either due to the server explicitly breaking the callback,
the callback promise lapsing or a local event obsoleting it.
Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/fs/afs/callback.c b/fs/afs/callback.c
index 9150104..d66cd03 100644
--- a/fs/afs/callback.c
+++ b/fs/afs/callback.c
@@ -212,7 +212,7 @@ void afs_init_callback_state(struct afs_server *server)
/*
* actually break a callback
*/
-void __afs_break_callback(struct afs_vnode *vnode)
+void __afs_break_callback(struct afs_vnode *vnode, enum afs_cb_break_reason reason)
{
_enter("");
@@ -223,13 +223,17 @@ void __afs_break_callback(struct afs_vnode *vnode)
if (vnode->lock_state == AFS_VNODE_LOCK_WAITING_FOR_CB)
afs_lock_may_be_available(vnode);
+
+ trace_afs_cb_break(&vnode->fid, vnode->cb_break, reason, true);
+ } else {
+ trace_afs_cb_break(&vnode->fid, vnode->cb_break, reason, false);
}
}
-void afs_break_callback(struct afs_vnode *vnode)
+void afs_break_callback(struct afs_vnode *vnode, enum afs_cb_break_reason reason)
{
write_seqlock(&vnode->cb_lock);
- __afs_break_callback(vnode);
+ __afs_break_callback(vnode, reason);
write_sequnlock(&vnode->cb_lock);
}
@@ -277,6 +281,8 @@ static void afs_break_one_callback(struct afs_server *server,
write_lock(&volume->cb_v_break_lock);
volume->cb_v_break++;
+ trace_afs_cb_break(fid, volume->cb_v_break,
+ afs_cb_break_for_volume_callback, false);
write_unlock(&volume->cb_v_break_lock);
} else {
data.volume = NULL;
@@ -285,8 +291,10 @@ static void afs_break_one_callback(struct afs_server *server,
afs_iget5_test, &data);
if (inode) {
vnode = AFS_FS_I(inode);
- afs_break_callback(vnode);
+ afs_break_callback(vnode, afs_cb_break_for_callback);
iput(inode);
+ } else {
+ trace_afs_cb_miss(fid, afs_cb_break_for_callback);
}
}
}