Module Name: src
Committed By: riastradh
Date: Thu Jul 17 18:42:38 UTC 2014
Modified Files:
src/sys/dev/usb: usb.c usbdi.h
Log Message:
Fix usb task queue locking.
To generate a diff of this commit:
cvs rdiff -u -r1.149 -r1.150 src/sys/dev/usb/usb.c
cvs rdiff -u -r1.89 -r1.90 src/sys/dev/usb/usbdi.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/usb/usb.c
diff -u src/sys/dev/usb/usb.c:1.149 src/sys/dev/usb/usb.c:1.150
--- src/sys/dev/usb/usb.c:1.149 Sun Mar 16 05:20:29 2014
+++ src/sys/dev/usb/usb.c Thu Jul 17 18:42:37 2014
@@ -1,4 +1,4 @@
-/* $NetBSD: usb.c,v 1.149 2014/03/16 05:20:29 dholland Exp $ */
+/* $NetBSD: usb.c,v 1.150 2014/07/17 18:42:37 riastradh Exp $ */
/*
* Copyright (c) 1998, 2002, 2008, 2012 The NetBSD Foundation, Inc.
@@ -37,7 +37,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: usb.c,v 1.149 2014/03/16 05:20:29 dholland Exp $");
+__KERNEL_RCSID(0, "$NetBSD: usb.c,v 1.150 2014/07/17 18:42:37 riastradh Exp $");
#ifdef _KERNEL_OPT
#include "opt_compat_netbsd.h"
@@ -355,28 +355,40 @@ usb_add_task(usbd_device_handle dev, str
{
struct usb_taskq *taskq;
+ KASSERT(0 <= queue);
+ KASSERT(queue < USB_NUM_TASKQS);
taskq = &usb_taskq[queue];
mutex_enter(&taskq->lock);
- if (task->queue == -1) {
+ if (atomic_cas_uint(&task->queue, USB_NUM_TASKQS, queue) ==
+ USB_NUM_TASKQS) {
DPRINTFN(2,("usb_add_task: task=%p\n", task));
TAILQ_INSERT_TAIL(&taskq->tasks, task, next);
task->queue = queue;
+ cv_signal(&taskq->cv);
} else {
DPRINTFN(3,("usb_add_task: task=%p on q\n", task));
}
- cv_signal(&taskq->cv);
mutex_exit(&taskq->lock);
}
+/*
+ * XXX This does not wait for completion! Most uses need such an
+ * operation. Urgh...
+ */
void
usb_rem_task(usbd_device_handle dev, struct usb_task *task)
{
+ unsigned queue;
- if (task->queue != -1) {
- struct usb_taskq *taskq = &usb_taskq[task->queue];
+ while ((queue = task->queue) != USB_NUM_TASKQS) {
+ struct usb_taskq *taskq = &usb_taskq[queue];
mutex_enter(&taskq->lock);
- TAILQ_REMOVE(&taskq->tasks, task, next);
- task->queue = -1;
+ if (__predict_true(task->queue == queue)) {
+ TAILQ_REMOVE(&taskq->tasks, task, next);
+ task->queue = USB_NUM_TASKQS;
+ mutex_exit(&taskq->lock);
+ break;
+ }
mutex_exit(&taskq->lock);
}
}
@@ -444,7 +456,7 @@ usb_task_thread(void *arg)
DPRINTFN(2,("usb_task_thread: woke up task=%p\n", task));
if (task != NULL) {
TAILQ_REMOVE(&taskq->tasks, task, next);
- task->queue = -1;
+ task->queue = USB_NUM_TASKQS;
mutex_exit(&taskq->lock);
if (!(task->flags & USB_TASKQ_MPSAFE))
Index: src/sys/dev/usb/usbdi.h
diff -u src/sys/dev/usb/usbdi.h:1.89 src/sys/dev/usb/usbdi.h:1.90
--- src/sys/dev/usb/usbdi.h:1.89 Thu Sep 26 07:25:31 2013
+++ src/sys/dev/usb/usbdi.h Thu Jul 17 18:42:37 2014
@@ -1,4 +1,4 @@
-/* $NetBSD: usbdi.h,v 1.89 2013/09/26 07:25:31 skrll Exp $ */
+/* $NetBSD: usbdi.h,v 1.90 2014/07/17 18:42:37 riastradh Exp $ */
/* $FreeBSD: src/sys/dev/usb/usbdi.h,v 1.18 1999/11/17 22:33:49 n_hibma Exp $ */
/*
@@ -202,7 +202,7 @@ struct usb_task {
TAILQ_ENTRY(usb_task) next;
void (*fun)(void *);
void *arg;
- int queue;
+ volatile unsigned queue;
int flags;
};
#define USB_TASKQ_HC 0
@@ -213,7 +213,7 @@ struct usb_task {
void usb_add_task(usbd_device_handle, struct usb_task *, int);
void usb_rem_task(usbd_device_handle, struct usb_task *);
-#define usb_init_task(t, f, a, fl) ((t)->fun = (f), (t)->arg = (a), (t)->queue = -1, (t)->flags = (fl))
+#define usb_init_task(t, f, a, fl) ((t)->fun = (f), (t)->arg = (a), (t)->queue = USB_NUM_TASKQS, (t)->flags = (fl))
struct usb_devno {
u_int16_t ud_vendor;
