[RFC PATCH 4/4] drm/xe: Add support for the drm cgroup

Maarten Lankhorst
2023-05-03T09:00:24Z

Add some code to implement basic support for the vram0, vram1 and stolen
memory regions.

I fear the try_charge code should probably be done inside TTM. This
code should interact with the shrinker, but for a simple RFC it's good
enough.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
---
drivers/gpu/drm/xe/xe_device.c | 4 ++++
drivers/gpu/drm/xe/xe_device_types.h | 4 ++++
drivers/gpu/drm/xe/xe_ttm_vram_mgr.c | 21 +++++++++++++++++++--
drivers/gpu/drm/xe/xe_ttm_vram_mgr_types.h | 5 +++++
4 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
index 45d6e5ff47fd..f0a5af15a662 100644
--- a/drivers/gpu/drm/xe/xe_device.c
+++ b/drivers/gpu/drm/xe/xe_device.c
@@ -291,6 +291,10 @@ int xe_device_probe(struct xe_device *xe)
/* Allocate and map stolen after potential VRAM resize */
xe_ttm_stolen_mgr_init(xe);

+ err = drmmcg_register_device(&xe->drm, &xe->cg);
+ if (err)
+ goto err_irq_shutdown;
+
/*
* Now that GT is initialized (TTM in particular),
* we can try to init display, and inherit the initial fb.
diff --git a/drivers/gpu/drm/xe/xe_device_types.h b/drivers/gpu/drm/xe/xe_device_types.h
index 1cb404e48aaa..04b85060cbec 100644
--- a/drivers/gpu/drm/xe/xe_device_types.h
+++ b/drivers/gpu/drm/xe/xe_device_types.h
@@ -12,6 +12,8 @@
#include <drm/drm_file.h>
#include <drm/ttm/ttm_device.h>

+#include <linux/cgroup_drm.h>
+
#include "xe_gt_types.h"
#include "xe_platform_types.h"
#include "xe_step_types.h"
@@ -55,6 +57,8 @@ struct xe_device {
/** @drm: drm device */
struct drm_device drm;

+ struct drmcgroup_device cg;
+
/** @info: device info */
struct intel_device_info {
/** @graphics_name: graphics IP name */
diff --git a/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c b/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c
index 73836b9b7fed..263cd4ef7b6d 100644
--- a/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c
+++ b/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c
@@ -50,6 +50,7 @@ static int xe_ttm_vram_mgr_new(struct ttm_resource_manager *man,
struct ttm_resource **res)
{
struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
+ struct xe_device *xe = ttm_to_xe_device(tbo->bdev);
struct xe_ttm_vram_mgr_resource *vres;
struct drm_buddy *mm = &mgr->mm;
u64 size, remaining_size, min_page_size;
@@ -116,9 +117,8 @@ static int xe_ttm_vram_mgr_new(struct ttm_resource_manager *man,

mutex_lock(&mgr->lock);
if (lpfn <= mgr->visible_size >> PAGE_SHIFT && size > mgr->visible_avail) {
- mutex_unlock(&mgr->lock);
err = -ENOSPC;
- goto error_fini;
+ goto error_unlock;
}

if (place->fpfn + (size >> PAGE_SHIFT) != place->lpfn &&
@@ -129,6 +129,10 @@ static int xe_ttm_vram_mgr_new(struct ttm_resource_manager *man,
lpfn = max_t(unsigned long, place->fpfn + (size >> PAGE_SHIFT), lpfn);
}

+ err = drmcg_try_charge(&vres->cg, &xe->cg, mgr->mem_type, vres->base.size);
+ if (err)
+ goto error_unlock;
+
remaining_size = size;
do {
/*
@@ -197,6 +201,8 @@ static int xe_ttm_vram_mgr_new(struct ttm_resource_manager *man,

error_free_blocks:
drm_buddy_free_list(mm, &vres->blocks);
+ drmcg_uncharge(vres->cg, &xe->cg, mgr->mem_type, vres->base.size);
+error_unlock:
mutex_unlock(&mgr->lock);
error_fini:
ttm_resource_fini(man, &vres->base);
@@ -211,6 +217,7 @@ static void xe_ttm_vram_mgr_del(struct ttm_resource_manager *man,
struct xe_ttm_vram_mgr_resource *vres =
to_xe_ttm_vram_mgr_resource(res);
struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
+ struct xe_device *xe = ttm_to_xe_device(man->bdev);
struct drm_buddy *mm = &mgr->mm;

mutex_lock(&mgr->lock);
@@ -218,6 +225,7 @@ static void xe_ttm_vram_mgr_del(struct ttm_resource_manager *man,
mgr->visible_avail += vres->used_visible_size;
mutex_unlock(&mgr->lock);

+ drmcg_uncharge(vres->cg, &xe->cg, mgr->mem_type, vres->base.size);
ttm_resource_fini(man, res);

kfree(vres);
@@ -337,6 +345,15 @@ int __xe_ttm_vram_mgr_init(struct xe_device *xe, struct xe_ttm_vram_mgr *mgr,
struct ttm_resource_manager *man = &mgr->manager;
int err;

+ xe->cg.regions[mem_type].size = size;
+
+ if (mem_type == XE_PL_STOLEN) {
+ xe->cg.regions[mem_type].name = "stolen";
+ } else {
+ xe->cg.regions[mem_type].name =
+ mem_type == XE_PL_VRAM0 ? "vram0" : "vram1";
+ }
+
man->func = &xe_ttm_vram_mgr_func;
mgr->mem_type = mem_type;
mutex_init(&mgr->lock);
diff --git a/drivers/gpu/drm/xe/xe_ttm_vram_mgr_types.h b/drivers/gpu/drm/xe/xe_ttm_vram_mgr_types.h
index 3d9417ff7434..232585d7ae69 100644
--- a/drivers/gpu/drm/xe/xe_ttm_vram_mgr_types.h
+++ b/drivers/gpu/drm/xe/xe_ttm_vram_mgr_types.h
@@ -9,6 +9,8 @@
#include <drm/drm_buddy.h>
#include <drm/ttm/ttm_device.h>

+struct drmcgroup_state;
+
struct xe_gt;

/**
@@ -47,6 +49,9 @@ struct xe_ttm_vram_mgr_resource {
u64 used_visible_size;
/** @flags: flags associated with the resource */
unsigned long flags;
+
+ /** @cg: cgroup this resource is charged to */
+ struct drmcgroup_state *cg;
};

#endif
--
2.34.1