On 2015년 08월 17일 14:29, Joonyoung Shim wrote: > On 08/16/2015 02:07 PM, Inki Dae wrote: >> On 2015년 07월 28일 17:53, Joonyoung Shim wrote: >>> The drm_gem_object_release() function already performs this cleanup, >>> so there is no reason to do it explicitly. >>> >>> Signed-off-by: Joonyoung Shim <jy0922.shim@xxxxxxxxxxx> >>> --- >>> drivers/gpu/drm/exynos/exynos_drm_gem.c | 3 --- >>> 1 file changed, 3 deletions(-) >>> >>> diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c >>> index c76aa8a..ab7d029 100644 >>> --- a/drivers/gpu/drm/exynos/exynos_drm_gem.c >>> +++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c >>> @@ -100,8 +100,6 @@ out: >>> exynos_drm_fini_buf(obj->dev, buf); >>> exynos_gem_obj->buffer = NULL; >>> >>> - drm_gem_free_mmap_offset(obj); >>> - >>> /* release file pointer to gem object. */ >>> drm_gem_object_release(obj); >>> >>> @@ -600,7 +598,6 @@ int exynos_drm_gem_mmap(struct file *filp, struct vm_area_struct *vma) >>> >>> err_close_vm: >>> drm_gem_vm_close(vma); >>> - drm_gem_free_mmap_offset(obj); >> >> Without previous patch, drm_gem_free_mmap_offset is required. I guess >> the reason you removed above line is that you thought >> drm_gem_object_release function would be called by drm_gem_vm_close >> function which drops a reference of the gem object. >> >> However, drm_gem_vm_close should be a pair with drm_gem_vm_open >> function. These will be called whenever a process opens or closes the >> VMA. So the reference count of the gem object had already been taken by >> open operation when a new reference to the VMA had been created. >> > > This changes is not related with drm_gem_vm_close and prior patch. Why > should free mmap offset when mmap operation is failed? The mmap offset > can be used repeatedly. Isn't vm space of vm manager still used even if any user-space process doesn't use the region? And if mmap is failed, then the user-space process will be terminated. Do you think it can be re-tried? However, mmap system call never return -EAGAIN. Is it reasonable to you? I cannot understand how the mmap offset can be re-used. So can you show me some example? > _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
