[PATCH v2 2/2] drm/xe: Use the filelist from drm for ccs_mode change

[Balasubramani Vivekanandan]

Drop the exclusive client count tracking and use the filelist from the
drm to track the active clients. This also ensures the clients created
internally by the driver won't block changing the ccs mode.

Fixes: ce8c161cbad4 ("drm/xe: Add ref counting for xe_file")
Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanandan at intel.com>
---
 drivers/gpu/drm/xe/xe_device.c       | 10 ----------
 drivers/gpu/drm/xe/xe_device_types.h |  9 ---------
 drivers/gpu/drm/xe/xe_gt_ccs_mode.c  |  9 +++++----
 3 files changed, 5 insertions(+), 23 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c
index a33d0c772616..c6bd6888cb7b 100644
--- a/drivers/gpu/drm/xe/xe_device.c
+++ b/drivers/gpu/drm/xe/xe_device.c
@@ -91,10 +91,6 @@ static int xe_file_open(struct drm_device *dev, struct drm_file *file)
 	mutex_init(&xef->exec_queue.lock);
 	xa_init_flags(&xef->exec_queue.xa, XA_FLAGS_ALLOC1);
 
-	spin_lock(&xe->clients.lock);
-	xe->clients.count++;
-	spin_unlock(&xe->clients.lock);
-
 	file->driver_priv = xef;
 	kref_init(&xef->refcount);
 
@@ -111,17 +107,12 @@ static int xe_file_open(struct drm_device *dev, struct drm_file *file)
 static void xe_file_destroy(struct kref *ref)
 {
 	struct xe_file *xef = container_of(ref, struct xe_file, refcount);
-	struct xe_device *xe = xef->xe;
 
 	xa_destroy(&xef->exec_queue.xa);
 	mutex_destroy(&xef->exec_queue.lock);
 	xa_destroy(&xef->vm.xa);
 	mutex_destroy(&xef->vm.lock);
 
-	spin_lock(&xe->clients.lock);
-	xe->clients.count--;
-	spin_unlock(&xe->clients.lock);
-
 	xe_drm_client_put(xef->client);
 	kfree(xef->process_name);
 	kfree(xef);
@@ -352,7 +343,6 @@ struct xe_device *xe_device_create(struct pci_dev *pdev,
 	xe->info.force_execlist = xe_modparam.force_execlist;
 
 	spin_lock_init(&xe->irq.lock);
-	spin_lock_init(&xe->clients.lock);
 
 	init_waitqueue_head(&xe->ufence_wq);
 
diff --git a/drivers/gpu/drm/xe/xe_device_types.h b/drivers/gpu/drm/xe/xe_device_types.h
index b97cd9828883..d4d53bb24740 100644
--- a/drivers/gpu/drm/xe/xe_device_types.h
+++ b/drivers/gpu/drm/xe/xe_device_types.h
@@ -425,15 +425,6 @@ struct xe_device {
 		struct workqueue_struct *wq;
 	} sriov;
 
-	/** @clients: drm clients info */
-	struct {
-		/** @clients.lock: Protects drm clients info */
-		spinlock_t lock;
-
-		/** @clients.count: number of drm clients */
-		u64 count;
-	} clients;
-
 	/** @usm: unified memory state */
 	struct {
 		/** @usm.asid: convert a ASID to VM */
diff --git a/drivers/gpu/drm/xe/xe_gt_ccs_mode.c b/drivers/gpu/drm/xe/xe_gt_ccs_mode.c
index 246190b3e2bb..b6adfb9f2030 100644
--- a/drivers/gpu/drm/xe/xe_gt_ccs_mode.c
+++ b/drivers/gpu/drm/xe/xe_gt_ccs_mode.c
@@ -139,9 +139,10 @@ ccs_mode_store(struct device *kdev, struct device_attribute *attr,
 	}
 
 	/* CCS mode can only be updated when there are no drm clients */
-	spin_lock(&xe->clients.lock);
-	if (xe->clients.count) {
-		spin_unlock(&xe->clients.lock);
+	mutex_lock(&xe->drm.filelist_mutex);
+	if (!list_empty(&xe->drm.filelist)) {
+		mutex_unlock(&xe->drm.filelist_mutex);
+		xe_gt_dbg(gt, "Rejecting compute mode change as there are active drm clients\n");
 		return -EBUSY;
 	}
 
@@ -152,7 +153,7 @@ ccs_mode_store(struct device *kdev, struct device_attribute *attr,
 		xe_gt_reset_async(gt);
 	}
 
-	spin_unlock(&xe->clients.lock);
+	mutex_unlock(&xe->drm.filelist_mutex);
 
 	return count;
 }
-- 
2.34.1