CVS commit: src/sys/external/bsd/drm2/dist/drm

[Taylor R Campbell]

Module Name:    src
Committed By:   riastradh
Date:           Sun Dec 19 11:08:03 UTC 2021

Modified Files:
        src/sys/external/bsd/drm2/dist/drm: drm_vblank.c

Log Message:
drm: Fix vblank locking.


To generate a diff of this commit:
cvs rdiff -u -r1.5 -r1.6 src/sys/external/bsd/drm2/dist/drm/drm_vblank.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.


Modified files:

Index: src/sys/external/bsd/drm2/dist/drm/drm_vblank.c
diff -u src/sys/external/bsd/drm2/dist/drm/drm_vblank.c:1.5 src/sys/external/bsd/drm2/dist/drm/drm_vblank.c:1.6
--- src/sys/external/bsd/drm2/dist/drm/drm_vblank.c:1.5	Sun Dec 19 09:52:34 2021
+++ src/sys/external/bsd/drm2/dist/drm/drm_vblank.c	Sun Dec 19 11:08:02 2021
@@ -1,4 +1,4 @@
-/*	$NetBSD: drm_vblank.c,v 1.5 2021/12/19 09:52:34 riastradh Exp $	*/
+/*	$NetBSD: drm_vblank.c,v 1.6 2021/12/19 11:08:02 riastradh Exp $	*/
 
 /*
  * drm_irq.c IRQ and vblank support
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: drm_vblank.c,v 1.5 2021/12/19 09:52:34 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: drm_vblank.c,v 1.6 2021/12/19 11:08:02 riastradh Exp $");
 
 #include <linux/export.h>
 #include <linux/moduleparam.h>
@@ -167,6 +167,8 @@ static void drm_reset_vblank_timestamp(s
 	ktime_t t_vblank;
 	int count = DRM_TIMESTAMP_MAXRETRIES;
 
+	assert_spin_locked(&dev->vbl_lock);
+
 	spin_lock(&dev->vblank_time_lock);
 
 	/*
@@ -218,6 +220,8 @@ static void drm_update_vblank_count(stru
 	int framedur_ns = vblank->framedur_ns;
 	u32 max_vblank_count = drm_max_vblank_count(dev, pipe);
 
+	assert_spin_locked(&dev->vbl_lock);
+
 	/*
 	 * Interrupts were disabled prior to this call, so deal with counter
 	 * wrap if needed.
@@ -1832,8 +1836,11 @@ bool drm_handle_vblank(struct drm_device
 	 */
 	spin_lock(&dev->vblank_time_lock);
 
+	spin_lock(&dev->vbl_lock);
+
 	/* Vblank irq handling disabled. Nothing to do. */
 	if (!vblank->enabled) {
+		spin_unlock(&dev->vbl_lock);
 		spin_unlock(&dev->vblank_time_lock);
 		spin_unlock_irqrestore(&dev->event_lock, irqflags);
 		return false;
@@ -1858,6 +1865,8 @@ bool drm_handle_vblank(struct drm_device
 		       drm_vblank_offdelay > 0 &&
 		       !atomic_read(&vblank->refcount));
 
+	spin_unlock(&dev->vbl_lock);
+
 	drm_handle_vblank_events(dev, pipe);
 
 	spin_unlock_irqrestore(&dev->event_lock, irqflags);