diff options
| author | Rob Clark <rob@ti.com> | 2012-09-05 21:48:38 +0000 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2012-10-02 22:15:39 +1000 |
| commit | f7eff60ea0e4e35732604e3591e2ff7b3ef41981 (patch) | |
| tree | a9dd6031479ce9585d7d0af061aa165ed9c5d49b /drivers/gpu/drm/exynos/exynos_drm_fbdev.c | |
| parent | 33cce6e9801f7d0184a636e9096a7cf7f8237ff9 (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')
| -rw-r--r-- | drivers/gpu/drm/exynos/exynos_drm_fbdev.c | 4 |
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 d5586cc75163..f4ac43356583 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 */ |