lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

cifs: reinstate sharing of SMB sessions sans races

Browse Source 
We do this by abandoning the global list of SMB sessions and instead
moving to a per-server list. This entails adding a new list head to the
TCP_Server_Info struct. The refcounting for the cifsSesInfo is moved to
a non-atomic variable. We have to protect it by a lock anyway, so there's
no benefit to making it an atomic. The list and refcount are protected
by the global cifs_tcp_ses_lock.

The patch also adds a new routines to find and put SMB sessions and
that properly take and put references under the lock.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
This commit is contained in:
Jeff Layton
2008-11-14 13:53:46 -05:00
committed by Steve French
parent e7ddee9037
commit 14fbf50d69
7 changed files with 175 additions and 166 deletions
Download Patch File Download Diff File Expand all files Collapse all files

17
fs/cifs/cifsfs.c
View File

@ -1031,24 +1031,24 @@ static int cifs_oplock_thread(void *dummyarg)
static int cifs_dnotify_thread(void *dummyarg)
{
struct list_head *tmp;
struct cifsSesInfo *ses;
struct TCP_Server_Info *server;
do {
if (try_to_freeze())
continue;
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(15*HZ);
read_lock(&GlobalSMBSeslock);
/* check if any stuck requests that need
to be woken up and wakeq so the
thread can wake up and error out */
list_for_each(tmp, &GlobalSMBSessionList) {
ses = list_entry(tmp, struct cifsSesInfo,
cifsSessionList);
if (ses->server && atomic_read(&ses->server->inFlight))
wake_up_all(&ses->server->response_q);
read_lock(&cifs_tcp_ses_lock);
list_for_each(tmp, &cifs_tcp_ses_list) {
server = list_entry(tmp, struct TCP_Server_Info,
tcp_ses_list);
if (atomic_read(&server->inFlight))
wake_up_all(&server->response_q);
}
read_unlock(&GlobalSMBSeslock);
read_unlock(&cifs_tcp_ses_lock);
} while (!kthread_should_stop());
return 0;
@ -1060,7 +1060,6 @@ init_cifs(void)
int rc = 0;
cifs_proc_init();
INIT_LIST_HEAD(&cifs_tcp_ses_list);
INIT_LIST_HEAD(&GlobalSMBSessionList); /* BB to be removed by jl */
INIT_LIST_HEAD(&GlobalTreeConnectionList); /* BB to be removed by jl */
INIT_LIST_HEAD(&GlobalOplock_Q);
#ifdef CONFIG_CIFS_EXPERIMENTAL