Attachment 316764 Details for Bug 462150 – ...also adds locking arround CIFSTCon()

[patch] ...also adds locking arround CIFSTCon()

linux-2.6-eliminate_usage_of_kthread_stop_for_cifsd.patch (text/plain), 4.54 KB, created by Olivier Fourdan on 2008-09-15 17:24:43 UTC

(hide)

Description:

Filename:

MIME Type:

Creator: Olivier Fourdan

Created: 2008-09-15 17:24:43 UTC

Size: 4.54 KB

patch

obsolete

>--- linux-2.6.18.i686/fs/cifs/connect.c.cifs	2008-09-09 15:31:57.000000000 +0100
>+++ linux-2.6.18.i686/fs/cifs/connect.c	2008-09-15 17:56:45.000000000 +0100
>@@ -139,7 +139,7 @@
> 	struct mid_q_entry *mid_entry;
> 
> 	spin_lock(&GlobalMid_Lock);
>-	if (kthread_should_stop()) {
>+	if (server->tcpStatus == CifsExiting) {
> 		/* the demux thread will exit normally
> 		next time through the loop */
> 		spin_unlock(&GlobalMid_Lock);
>@@ -201,7 +201,8 @@
> 	spin_unlock(&GlobalMid_Lock);
> 	up(&server->tcpSem);
> 
>-	while ((!kthread_should_stop()) && (server->tcpStatus != CifsGood)) {
>+	while ((server->tcpStatus != CifsExiting) &&
>+	       (server->tcpStatus != CifsGood)) {
> #if LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 12)
> 		try_to_freeze();
> #endif
>@@ -220,7 +221,7 @@
> 		} else {
> 			atomic_inc(&tcpSesReconnectCount);
> 			spin_lock(&GlobalMid_Lock);
>-			if (!kthread_should_stop())
>+			if (server->tcpStatus != CifsExiting)
> 				server->tcpStatus = CifsGood;
> 			server->sequence_number = 0;
> 			spin_unlock(&GlobalMid_Lock);
>@@ -394,7 +395,7 @@
> 	set_freezable();
> #endif
> 
>-	while (!kthread_should_stop()) {
>+	while (server->tcpStatus != CifsExiting) {
> #if LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 12)
> 		if (try_to_freeze())
> 			continue;
>@@ -444,7 +445,7 @@
> 				&iov, 1, pdu_length, 0 /* BB other flags? */);
> #endif
> 
>-		if (kthread_should_stop()) {
>+		if (server->tcpStatus == CifsExiting) {
> 			break;
> 		} else if (server->tcpStatus == CifsNeedReconnect) {
> 			cFYI(1, ("Reconnect after server stopped responding"));
>@@ -578,7 +579,7 @@
> 			length = kernel_recvmsg(csocket, &smb_msg, &iov, 1,
> 						pdu_length - total_read, 0);
> #endif
>-			if (kthread_should_stop() ||
>+			if ((server->tcpStatus == CifsExiting) ||
> 			    (length == -EINTR)) {
> 				/* then will exit */
> 				reconnect = 2;
>@@ -707,14 +708,6 @@
> 	spin_unlock(&GlobalMid_Lock);
> 	wake_up_all(&server->response_q);
> 
>-	/* don't exit until kthread_stop is called */
>-	set_current_state(TASK_UNINTERRUPTIBLE);
>-	while (!kthread_should_stop()) {
>-		schedule();
>-		set_current_state(TASK_UNINTERRUPTIBLE);
>-	}
>-	set_current_state(TASK_RUNNING);
>-
> 	/* check if we have blocked requests that need to free */
> 	/* Note that cifs_max_pending is normally 50, but
> 	can be set at module install time to as little as two */
>@@ -1491,7 +1484,9 @@
> 		temp_unc[1] = '\\';
> 		strcpy(temp_unc + 2, pSesInfo->serverName);
> 		strcpy(temp_unc + 2 + strlen(pSesInfo->serverName), "\\IPC$");
>+		down(&pSesInfo->sesSem);
> 		rc = CIFSTCon(xid, pSesInfo, temp_unc, NULL, nls_codepage);
>+		up(&pSesInfo->sesSem);
> 		cFYI(1,
> 		     ("CIFS Tcon rc = %d ipc_tid = %d", rc, pSesInfo->ipc_tid));
> 		kfree(temp_unc);
>@@ -2213,9 +2208,11 @@
> 					/* BB Do we need to wrap sesSem around
> 					 * this TCon call and Unix SetFS as
> 					 * we do on SessSetup and reconnect? */
>+		 			down(&pSesInfo->sesSem);
> 					rc = CIFSTCon(xid, pSesInfo,
> 						volume_info.UNC,
> 						tcon, cifs_sb->local_nls);
>+					up(&pSesInfo->sesSem);
> 					cFYI(1, ("CIFS Tcon rc = %d", rc));
> 				}
> 				if (!rc) {
>@@ -2246,14 +2243,7 @@
> 			spin_lock(&GlobalMid_Lock);
> 			srvTcp->tcpStatus = CifsExiting;
> 			spin_unlock(&GlobalMid_Lock);
>-			if (srvTcp->tsk) {
>-				/* If we could verify that kthread_stop would
>-				   always wake up processes blocked in
>-				   tcp in recv_mesg then we could remove the
>-				   send_sig call */
>-				force_sig(SIGKILL, srvTcp->tsk);
>-				kthread_stop(srvTcp->tsk);
>-			}
>+			force_sig(SIGKILL, srvTcp->tsk);
> 		}
> 		 /* If find_unc succeeded then rc == 0 so we can not end */
> 		if (tcon)  /* up accidently freeing someone elses tcon struct */
>@@ -2267,18 +2257,18 @@
> 					/* if the socketUseCount is now zero */
> 					if ((temp_rc == -ESHUTDOWN) &&
> 					    (pSesInfo->server) &&
>-					    (pSesInfo->server->tsk)) {
>+					    (pSesInfo->server->tsk))
> 						force_sig(SIGKILL,
> 							pSesInfo->server->tsk);
>-						kthread_stop(pSesInfo->server->tsk);
>-					}
> 				} else {
> 					cFYI(1, ("No session or bad tcon"));
> 					if ((pSesInfo->server) &&
> 					    (pSesInfo->server->tsk)) {
>+						spin_lock(&GlobalMid_Lock);
>+						srvTcp->tcpStatus = CifsExiting;
>+						spin_unlock(&GlobalMid_Lock);
> 						force_sig(SIGKILL,
> 							pSesInfo->server->tsk);
>-						kthread_stop(pSesInfo->server->tsk);
> 					}
> 				}
> 				sesInfoFree(pSesInfo);
>@@ -3602,10 +3592,8 @@
> 				return 0;
> 			} else if (rc == -ESHUTDOWN) {
> 				cFYI(1, ("Waking up socket by sending signal"));
>-				if (cifsd_task) {
>+				if (cifsd_task)
> 					force_sig(SIGKILL, cifsd_task);
>-					kthread_stop(cifsd_task);
>-				}
> 				rc = 0;
> 			} /* else - we have an smb session
> 				left on this socket do not kill cifsd */

Actions: View | Diff

Attachments on bug 462150: 316764 | 316776 | 316932 | 319417 | 319418 | 319419 | 319420 | 320000 | 320011 | 320186