And new pages_pin_count field to struct drm_gem_shmem_object that will determine whether pages are evictable by memory shrinker. The pages will be evictable only when pages_pin_count=0. This patch prepares code for addition of the memory shrinker that will utilize the new field.
Signed-off-by: Dmitry Osipenko <[email protected]> --- drivers/gpu/drm/drm_gem_shmem_helper.c | 12 +++++++++++- include/drm/drm_gem_shmem_helper.h | 9 +++++++++ 2 files changed, 20 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index 49ab49454783..97b40676bdfa 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -280,12 +280,17 @@ EXPORT_SYMBOL(drm_gem_shmem_put_pages); int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem) { struct drm_gem_object *obj = &shmem->base; + int ret; dma_resv_assert_held(shmem->base.resv); drm_WARN_ON(obj->dev, obj->import_attach); - return drm_gem_shmem_get_pages(shmem); + ret = drm_gem_shmem_get_pages(shmem); + if (!ret) + shmem->pages_pin_count++; + + return ret; } EXPORT_SYMBOL(drm_gem_shmem_pin); @@ -304,7 +309,12 @@ void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem) drm_WARN_ON(obj->dev, obj->import_attach); + if (drm_WARN_ON_ONCE(obj->dev, !shmem->pages_pin_count)) + return; + drm_gem_shmem_put_pages(shmem); + + shmem->pages_pin_count--; } EXPORT_SYMBOL(drm_gem_shmem_unpin); diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h index 20ddcd799df9..7d823c9fc480 100644 --- a/include/drm/drm_gem_shmem_helper.h +++ b/include/drm/drm_gem_shmem_helper.h @@ -39,6 +39,15 @@ struct drm_gem_shmem_object { */ unsigned int pages_use_count; + /** + * @pages_pin_count: + * + * Reference count on the pinned pages table. + * The pages allowed to be evicted by memory shrinker + * only when the count is zero. + */ + unsigned int pages_pin_count; + /** * @madv: State for madvise * -- 2.39.2
