[PATCH RFC 11/12] drm/gem: Add cgroup memory accounting

Maxime Ripard
2025-03-10T12:06:49Z

In order to support any device using the GEM support, let's charge any
GEM DMA allocation into the dmem cgroup.

Signed-off-by: Maxime Ripard <mripard@kernel.org>
---
drivers/gpu/drm/drm_gem.c | 5 +++++
drivers/gpu/drm/drm_gem_dma_helper.c | 6 ++++++
include/drm/drm_device.h | 1 +
include/drm/drm_gem.h | 2 ++
4 files changed, 14 insertions(+)

diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index ee811764c3df4b4e9c377a66afd4967512ba2001..e04733cb49353cf3ff9672d883b106a083f80d86 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -108,10 +108,11 @@ drm_gem_init(struct drm_device *dev)
dev->vma_offset_manager = vma_offset_manager;
drm_vma_offset_manager_init(vma_offset_manager,
DRM_FILE_PAGE_OFFSET_START,
DRM_FILE_PAGE_OFFSET_SIZE);

+
return drmm_add_action(dev, drm_gem_init_release, NULL);
}

/**
* drm_gem_object_init_with_mnt - initialize an allocated shmem-backed GEM
@@ -973,10 +974,14 @@ drm_gem_release(struct drm_device *dev, struct drm_file *file_private)
* drm_gem_object_init().
*/
void
drm_gem_object_release(struct drm_gem_object *obj)
{
+
+ if (obj->cgroup_pool_state)
+ dmem_cgroup_uncharge(obj->cgroup_pool_state, obj->size);
+
if (obj->filp)
fput(obj->filp);

drm_gem_private_object_fini(obj);

diff --git a/drivers/gpu/drm/drm_gem_dma_helper.c b/drivers/gpu/drm/drm_gem_dma_helper.c
index 16988d316a6dc702310fa44c15c92dc67b82802b..6236feb67ddd6338f0f597a0606377e0352ca6ed 100644
--- a/drivers/gpu/drm/drm_gem_dma_helper.c
+++ b/drivers/gpu/drm/drm_gem_dma_helper.c
@@ -104,10 +104,16 @@ __drm_gem_dma_create(struct drm_device *drm, size_t size, bool private)
if (ret) {
drm_gem_object_release(gem_obj);
goto error;
}

+ ret = dmem_cgroup_try_charge(dma_get_dmem_cgroup_region(drm->dev),
+ size,
+ &dma_obj->base.cgroup_pool_state, NULL);
+ if (ret)
+ goto error;
+
return dma_obj;

error:
kfree(dma_obj);
return ERR_PTR(ret);
diff --git a/include/drm/drm_device.h b/include/drm/drm_device.h
index c91f87b5242d7a499917eb4aeb6ca8350f856eb3..58987f39ba8718eb768f6261fb0a1fbf16b38549 100644
--- a/include/drm/drm_device.h
+++ b/include/drm/drm_device.h
@@ -1,8 +1,9 @@
#ifndef _DRM_DEVICE_H_
#define _DRM_DEVICE_H_

+#include <linux/cgroup_dmem.h>
#include <linux/list.h>
#include <linux/kref.h>
#include <linux/mutex.h>
#include <linux/idr.h>

diff --git a/include/drm/drm_gem.h b/include/drm/drm_gem.h
index fdae947682cd0b7b06db5e35e120f049a0f30179..95fe8ed48a26204020bb47d6074689829c410465 100644
--- a/include/drm/drm_gem.h
+++ b/include/drm/drm_gem.h
@@ -430,10 +430,12 @@ struct drm_gem_object {
* @lru:
*
* The current LRU list that the GEM object is on.
*/
struct drm_gem_lru *lru;
+
+ struct dmem_cgroup_pool_state *cgroup_pool_state;
};

/**
* DRM_GEM_FOPS - Default drm GEM file operations
*

--
2.48.1