path: root/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
diff options
authorRob Clark <rob@ti.com>2012-09-05 21:48:38 +0000
committerDave Airlie <airlied@redhat.com>2012-10-02 22:15:39 +1000
commitf7eff60ea0e4e35732604e3591e2ff7b3ef41981 (patch)
treea9dd6031479ce9585d7d0af061aa165ed9c5d49b /drivers/gpu/drm/exynos/exynos_drm_fbdev.c
parent33cce6e9801f7d0184a636e9096a7cf7f8237ff9 (diff)
drm: refcnt drm_framebuffer (v4.1)
This simplifies drm fb lifetime, and if the crtc/plane needs to hold a ref to the fb when disabling a pipe until the next vblank, this avoids the need to make disabling an overlay synchronous. This is a problem that shows up when userspace is using a drm plane to implement a hw cursor.. making overlay disable synchronous causes a performance problem when x11 is rapidly enabling/disabling the hw cursor. But not making it synchronous opens up a race condition for crashing if userspace turns around and immediately deletes the fb. Refcnt'ing the fb makes it possible to solve this problem. v1: original v2: add drm_framebuffer_remove() which is called in all paths where fb->funcs->destroy() was directly called before. This cleans up the CRTCs/planes that the fb was attached to. You should only directly use drm_framebuffer_unreference() if you are also using drm_framebuffer_reference() to keep a ref to the fb. v3: add comment explaining the fb refcount v4: remove duplicate 'list_del(&fb->filp_head)' [airlied: v4.1: fix local rejection] Signed-off-by: Rob Clark <rob@ti.com> Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'drivers/gpu/drm/exynos/exynos_drm_fbdev.c')
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
index d5586cc7516..f4ac4335658 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
@@ -266,8 +266,8 @@ static void exynos_drm_fbdev_destroy(struct drm_device *dev,
/* release drm framebuffer and real buffer */
if (fb_helper->fb && fb_helper->fb->funcs) {
fb = fb_helper->fb;
- if (fb && fb->funcs->destroy)
- fb->funcs->destroy(fb);
+ if (fb)
+ drm_framebuffer_remove(fb);
/* release linux framebuffer */