drm/msm: Track potentially evictable objects

Objects that are potential for swapping out are (1) willneed (ie. if
they are purgable/MADV_WONTNEED we can just free the pages without them
having to land in swap), (2) not on an active list, (3) not dma-buf
imported or exported, and (4) not vmap'd.  This repurposes the purged
list for objects that do not have backing pages (either because they
have not been pinned for the first time yet, or in a later patch because
they have been unpinned/evicted.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Link: https://lore.kernel.org/r/20210405174532.1441497-7-robdclark@gmail.com
Signed-off-by: Rob Clark <robdclark@chromium.org>

1 files changed, 34 insertions, 10 deletions

diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 124306bec6f8..58051bc54a9c 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -130,6 +130,9 @@ static struct page **get_pages(struct drm_gem_object *obj)
 		 */
 		if (msm_obj->flags & (MSM_BO_WC|MSM_BO_UNCACHED))
 			sync_for_device(msm_obj);
+
+		GEM_WARN_ON(msm_obj->active_count);
+		update_inactive(msm_obj);
 	}
 
 	return msm_obj->pages;
@@ -428,7 +431,7 @@ static int msm_gem_pin_iova(struct drm_gem_object *obj,
 	struct msm_gem_object *msm_obj = to_msm_bo(obj);
 	struct msm_gem_vma *vma;
 	struct page **pages;
-	int prot = IOMMU_READ;
+	int ret, prot = IOMMU_READ;
 
 	if (!(msm_obj->flags & MSM_BO_GPU_READONLY))
 		prot |= IOMMU_WRITE;
@@ -449,8 +452,13 @@ static int msm_gem_pin_iova(struct drm_gem_object *obj,
 	if (IS_ERR(pages))
 		return PTR_ERR(pages);
 
-	return msm_gem_map_vma(aspace, vma, prot,
+	ret = msm_gem_map_vma(aspace, vma, prot,
 			msm_obj->sgt, obj->size >> PAGE_SHIFT);
+
+	if (!ret)
+		msm_obj->pin_count++;
+
+	return ret;
 }
 
 static int get_and_pin_iova_range_locked(struct drm_gem_object *obj,
@@ -542,14 +550,21 @@ uint64_t msm_gem_iova(struct drm_gem_object *obj,
 void msm_gem_unpin_iova_locked(struct drm_gem_object *obj,
 		struct msm_gem_address_space *aspace)
 {
+	struct msm_gem_object *msm_obj = to_msm_bo(obj);
 	struct msm_gem_vma *vma;
 
 	GEM_WARN_ON(!msm_gem_is_locked(obj));
 
 	vma = lookup_vma(obj, aspace);
 
-	if (!GEM_WARN_ON(!vma))
+	if (!GEM_WARN_ON(!vma)) {
 		msm_gem_unmap_vma(aspace, vma);
+
+		msm_obj->pin_count--;
+		GEM_WARN_ON(msm_obj->pin_count < 0);
+
+		update_inactive(msm_obj);
+	}
 }
 
 /*
@@ -800,9 +815,12 @@ void msm_gem_active_get(struct drm_gem_object *obj, struct msm_gpu *gpu)
 	GEM_WARN_ON(!msm_gem_is_locked(obj));
 	GEM_WARN_ON(msm_obj->madv != MSM_MADV_WILLNEED);
 	GEM_WARN_ON(msm_obj->dontneed);
+	GEM_WARN_ON(!msm_obj->sgt);
 
 	if (msm_obj->active_count++ == 0) {
 		mutex_lock(&priv->mm_lock);
+		if (msm_obj->evictable)
+			mark_unevictable(msm_obj);
 		list_del(&msm_obj->mm_list);
 		list_add_tail(&msm_obj->mm_list, &gpu->active_list);
 		mutex_unlock(&priv->mm_lock);
@@ -825,21 +843,28 @@ static void update_inactive(struct msm_gem_object *msm_obj)
 {
 	struct msm_drm_private *priv = msm_obj->base.dev->dev_private;
 
+	GEM_WARN_ON(!msm_gem_is_locked(&msm_obj->base));
+
+	if (msm_obj->active_count != 0)
+		return;
+
 	mutex_lock(&priv->mm_lock);
-	GEM_WARN_ON(msm_obj->active_count != 0);
 
 	if (msm_obj->dontneed)
 		mark_unpurgeable(msm_obj);
+	if (msm_obj->evictable)
+		mark_unevictable(msm_obj);
 
 	list_del(&msm_obj->mm_list);
-	if (msm_obj->madv == MSM_MADV_WILLNEED) {
+	if ((msm_obj->madv == MSM_MADV_WILLNEED) && msm_obj->sgt) {
 		list_add_tail(&msm_obj->mm_list, &priv->inactive_willneed);
+		mark_evictable(msm_obj);
 	} else if (msm_obj->madv == MSM_MADV_DONTNEED) {
 		list_add_tail(&msm_obj->mm_list, &priv->inactive_dontneed);
 		mark_purgeable(msm_obj);
 	} else {
-		GEM_WARN_ON(msm_obj->madv != __MSM_MADV_PURGED);
-		list_add_tail(&msm_obj->mm_list, &priv->inactive_purged);
+		GEM_WARN_ON((msm_obj->madv != __MSM_MADV_PURGED) && msm_obj->sgt);
+		list_add_tail(&msm_obj->mm_list, &priv->inactive_unpinned);
 	}
 
 	mutex_unlock(&priv->mm_lock);
@@ -1201,8 +1226,7 @@ static struct drm_gem_object *_msm_gem_new(struct drm_device *dev,
 	}
 
 	mutex_lock(&priv->mm_lock);
-	/* Initially obj is idle, obj->madv == WILLNEED: */
-	list_add_tail(&msm_obj->mm_list, &priv->inactive_willneed);
+	list_add_tail(&msm_obj->mm_list, &priv->inactive_unpinned);
 	mutex_unlock(&priv->mm_lock);
 
 	mutex_lock(&priv->obj_lock);
@@ -1276,7 +1300,7 @@ struct drm_gem_object *msm_gem_import(struct drm_device *dev,
 	msm_gem_unlock(obj);
 
 	mutex_lock(&priv->mm_lock);
-	list_add_tail(&msm_obj->mm_list, &priv->inactive_willneed);
+	list_add_tail(&msm_obj->mm_list, &priv->inactive_unpinned);
 	mutex_unlock(&priv->mm_lock);
 
 	mutex_lock(&priv->obj_lock);