From 44a2d56429bc9d1f9edd56761bfb504ed68fef01 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 27 Nov 2017 12:17:03 +0100 Subject: [PATCH] drm/via: use monotonic time for VIA_WAIT_IRQ The normal DRM vblank interrupt events started using monotonic times in commit c61eef726a78 ("drm: add support for monotonic vblank timestamps"), which is useful for a number of reasons, including the possible y2038 overflow. The VIA_WAIT_IRQ ioctl uses the same drm_wait_vblank_reply as DRM_IOCTL_WAIT_VBLANK, but still uses wall-clock time. This converts it to using monotonic time as well, which is more consistent, and avoids problems with the y2038 overflow as well as synchronization issues when the real time skips. I could not find the matching user space that calls the VIA_WAIT_IRQ ioctl to verify that this is safe, but it very likely is. Please either test or review the user space side before applying this. Signed-off-by: Arnd Bergmann Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20171127111728.1710742-1-arnd@arndb.de --- drivers/gpu/drm/via/via_irq.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/via/via_irq.c b/drivers/gpu/drm/via/via_irq.c index 24e71578af4d..c96830ccc0ec 100644 --- a/drivers/gpu/drm/via/via_irq.c +++ b/drivers/gpu/drm/via/via_irq.c @@ -343,7 +343,7 @@ void via_driver_irq_uninstall(struct drm_device *dev) int via_wait_irq(struct drm_device *dev, void *data, struct drm_file *file_priv) { drm_via_irqwait_t *irqwait = data; - struct timeval now; + struct timespec64 now; int ret = 0; drm_via_private_t *dev_priv = (drm_via_private_t *) dev->dev_private; drm_via_irq_t *cur_irq = dev_priv->via_irqs; @@ -377,9 +377,9 @@ int via_wait_irq(struct drm_device *dev, void *data, struct drm_file *file_priv) ret = via_driver_irq_wait(dev, irqwait->request.irq, force_sequence, &irqwait->request.sequence); - do_gettimeofday(&now); + ktime_get_ts64(&now); irqwait->reply.tval_sec = now.tv_sec; - irqwait->reply.tval_usec = now.tv_usec; + irqwait->reply.tval_usec = now.tv_nsec / NSEC_PER_USEC; return ret; }