drm/vmwgfx: Remove the dedicated memory accounting

vmwgfx shared very elaborate memory accounting with ttm. It was moved
from ttm to vmwgfx in change
f07069da6b4c ("drm/ttm: move memory accounting into vmwgfx v4")
but because of complexity it was hard to maintain. Some parts of the code
weren't freeing memory correctly and  some were missing accounting all
together. While those would be fairly easy to fix the fundamental reason
for memory accounting in the driver was the ability to invoke shrinker
which is part of TTM code as well (with support for unified memory
hopefully coming soon).

That meant that vmwgfx had a lot of code that was either unused or
duplicating code from TTM. Removing this code also prevents excessive
calls to global swapout which were common during memory pressure
because both vmwgfx and TTM would invoke the shrinker when memory
usage reached half of RAM.

Fixes: f07069da6b4c ("drm/ttm: move memory accounting into vmwgfx v4")
Signed-off-by: Zack Rusin <zackr@vmware.com>
Reviewed-by: Martin Krastev <krastevm@vmware.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211206172620.3139754-2-zack@kde.org

1 files changed, 1 insertions, 19 deletions

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c b/drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c
index 922317d1acc8..7bc99b1279f7 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_page_dirty.c
@@ -57,7 +57,6 @@ enum vmw_bo_dirty_method {
  * @ref_count: Reference count for this structure
  * @bitmap_size: The size of the bitmap in bits. Typically equal to the
  * nuber of pages in the bo.
- * @size: The accounting size for this struct.
  * @bitmap: A bitmap where each bit represents a page. A set bit means a
  * dirty page.
  */
@@ -68,7 +67,6 @@ struct vmw_bo_dirty {
 	unsigned int change_count;
 	unsigned int ref_count;
 	unsigned long bitmap_size;
-	size_t size;
 	unsigned long bitmap[];
 };
 
@@ -233,12 +231,8 @@ int vmw_bo_dirty_add(struct vmw_buffer_object *vbo)
 {
 	struct vmw_bo_dirty *dirty = vbo->dirty;
 	pgoff_t num_pages = vbo->base.resource->num_pages;
-	size_t size, acc_size;
+	size_t size;
 	int ret;
-	static struct ttm_operation_ctx ctx = {
-		.interruptible = false,
-		.no_wait_gpu = false
-	};
 
 	if (dirty) {
 		dirty->ref_count++;
@@ -246,20 +240,12 @@ int vmw_bo_dirty_add(struct vmw_buffer_object *vbo)
 	}
 
 	size = sizeof(*dirty) + BITS_TO_LONGS(num_pages) * sizeof(long);
-	acc_size = ttm_round_pot(size);
-	ret = ttm_mem_global_alloc(&ttm_mem_glob, acc_size, &ctx);
-	if (ret) {
-		VMW_DEBUG_USER("Out of graphics memory for buffer object "
-			       "dirty tracker.\n");
-		return ret;
-	}
 	dirty = kvzalloc(size, GFP_KERNEL);
 	if (!dirty) {
 		ret = -ENOMEM;
 		goto out_no_dirty;
 	}
 
-	dirty->size = acc_size;
 	dirty->bitmap_size = num_pages;
 	dirty->start = dirty->bitmap_size;
 	dirty->end = 0;
@@ -285,7 +271,6 @@ int vmw_bo_dirty_add(struct vmw_buffer_object *vbo)
 	return 0;
 
 out_no_dirty:
-	ttm_mem_global_free(&ttm_mem_glob, acc_size);
 	return ret;
 }
 
@@ -304,10 +289,7 @@ void vmw_bo_dirty_release(struct vmw_buffer_object *vbo)
 	struct vmw_bo_dirty *dirty = vbo->dirty;
 
 	if (dirty && --dirty->ref_count == 0) {
-		size_t acc_size = dirty->size;
-
 		kvfree(dirty);
-		ttm_mem_global_free(&ttm_mem_glob, acc_size);
 		vbo->dirty = NULL;
 	}
 }