smb3: show number of current open files in /proc/fs/cifs/Stats
To allow better debugging (for example applications with
handle leaks, or complex reconnect scenarios) display the
number of open files (on the client) and number of open
server file handles for each tcon in /proc/fs/cifs/Stats.
Note that open files on server is one larger than local
due to handle caching (in this case of the root of
the share). In this example there are two local
open files, and three (two file and one directory handle)
open on the server.
Sample output:
$ cat /proc/fs/cifs/Stats
Resources in use
CIFS Session: 1
Share (unique mount targets): 2
SMB Request/Response Buffer: 1 Pool size: 5
SMB Small Req/Resp Buffer: 1 Pool size: 30
Operations (MIDs): 0
0 session 0 share reconnects
Total vfs operations: 36 maximum at one time: 2
1) \\localhost\test
SMBs: 69
Bytes read: 27 Bytes written: 0
Open files: 2 total (local), 3 open on server
TreeConnects: 1 total 0 failed
TreeDisconnects: 0 total 0 failed
Creates: 19 total 0 failed
Closes: 16 total 0 failed
...
Signed-off-by: Steve French <stfrench@microsoft.com>
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 84477e9..c620d4b 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -334,6 +334,7 @@ cifs_new_fileinfo(struct cifs_fid *fid, struct file *file,
server->ops->set_fid(cfile, fid, oplock);
list_add(&cfile->tlist, &tcon->openFileList);
+ atomic_inc(&tcon->num_local_opens);
/* if readable file instance put first in list*/
if (file->f_mode & FMODE_READ)
@@ -395,6 +396,7 @@ void cifsFileInfo_put(struct cifsFileInfo *cifs_file)
/* remove it from the lists */
list_del(&cifs_file->flist);
list_del(&cifs_file->tlist);
+ atomic_dec(&tcon->num_local_opens);
if (list_empty(&cifsi->openFileList)) {
cifs_dbg(FYI, "closing last open instance for inode %p\n",