Before this commit, drmcg limits are updated but enforcement is delayed until the next time the driver check against the new limit. While this is sufficient for certain resources, a more proactive enforcement may be needed for other resources.
Introducing an optional drmcg_limit_updated callback for the DRM drivers. When defined, it will be called in two scenarios: 1) When limits are updated for a particular cgroup, the callback will be triggered for each task in the updated cgroup. 2) When a task is migrated from one cgroup to another, the callback will be triggered for each resource type for the migrated task.
Change-Id: I68187a72818b855b5f295aefcb241cda8ab63b00 Signed-off-by: Kenny Ho Kenny.Ho@amd.com --- include/drm/drm_drv.h | 10 ++++++++ kernel/cgroup/drm.c | 57 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 67 insertions(+)
diff --git a/include/drm/drm_drv.h b/include/drm/drm_drv.h index c8a37a08d98d..7e588b874a27 100644 --- a/include/drm/drm_drv.h +++ b/include/drm/drm_drv.h @@ -669,6 +669,16 @@ struct drm_driver { void (*drmcg_custom_init)(struct drm_device *dev, struct drmcg_props *props);
+ /** + * @drmcg_limit_updated + * + * Optional callback + */ + void (*drmcg_limit_updated)(struct drm_device *dev, + struct task_struct *task,\ + struct drmcg_device_resource *ddr, + enum drmcg_res_type res_type); + /** * @gem_vm_ops: Driver private ops for this object */ diff --git a/kernel/cgroup/drm.c b/kernel/cgroup/drm.c index 18c4368e2c29..99772e5d9ccc 100644 --- a/kernel/cgroup/drm.c +++ b/kernel/cgroup/drm.c @@ -621,6 +621,23 @@ static void drmcg_nested_limit_parse(struct kernfs_open_file *of, } }
+static void drmcg_limit_updated(struct drm_device *dev, struct drmcg *drmcg, + enum drmcg_res_type res_type) +{ + struct drmcg_device_resource *ddr = + drmcg->dev_resources[dev->primary->index]; + struct css_task_iter it; + struct task_struct *task; + + css_task_iter_start(&drmcg->css.cgroup->self, + CSS_TASK_ITER_PROCS, &it); + while ((task = css_task_iter_next(&it))) { + dev->driver->drmcg_limit_updated(dev, task, + ddr, res_type); + } + css_task_iter_end(&it); +} + static ssize_t drmcg_limit_write(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { @@ -726,6 +743,10 @@ static ssize_t drmcg_limit_write(struct kernfs_open_file *of, char *buf, default: break; } + + if (dm->dev->driver->drmcg_limit_updated) + drmcg_limit_updated(dm->dev, drmcg, type); + drm_dev_put(dm->dev); /* release from drm_minor_acquire */ }
@@ -863,9 +884,45 @@ struct cftype files[] = { { } /* terminate */ };
+static int drmcg_attach_fn(int id, void *ptr, void *data) +{ + struct drm_minor *minor = ptr; + struct task_struct *task = data; + struct drm_device *dev; + + if (minor->type != DRM_MINOR_PRIMARY) + return 0; + + dev = minor->dev; + + if (dev->driver->drmcg_limit_updated) { + struct drmcg *drmcg = drmcg_get(task); + struct drmcg_device_resource *ddr = + drmcg->dev_resources[minor->index]; + enum drmcg_res_type type; + + for (type = 0; type < __DRMCG_TYPE_LAST; type++) + dev->driver->drmcg_limit_updated(dev, task, ddr, type); + + drmcg_put(drmcg); + } + + return 0; +} + +static void drmcg_attach(struct cgroup_taskset *tset) +{ + struct task_struct *task; + struct cgroup_subsys_state *css; + + cgroup_taskset_for_each(task, css, tset) + drm_minor_for_each(&drmcg_attach_fn, task); +} + struct cgroup_subsys drm_cgrp_subsys = { .css_alloc = drmcg_css_alloc, .css_free = drmcg_css_free, + .attach = drmcg_attach, .early_init = false, .legacy_cftypes = files, .dfl_cftypes = files,