From 77a011012d7d8b98368a763bf74317c6d5ce00f1 Mon Sep 17 00:00:00 2001 From: Matthew Brost Date: Mon, 1 Apr 2024 15:19:11 -0700 Subject: drm/xe: Use ordered wq for preempt fence waiting Preempt fences can sleep waiting for an exec queue suspend operation to complete. If the system_unbound_wq is used for waiting and the number of waiters exceeds max_active this will result in other users of the system_unbound_wq getting starved. Use a device private work queue for preempt fences to avoid starvation of the system_unbound_wq. Even though suspend operations can complete out-of-order, all suspend operations within a VM need to complete before the preempt rebind worker can start. With that, use a device private ordered wq for preempt fence waiting. v2: - Add comment about cleanup on failure (Matt R) - Update commit message (Lucas) Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs") Signed-off-by: Matthew Brost Reviewed-by: Lucas De Marchi Link: https://patchwork.freedesktop.org/patch/msgid/20240401221913.139672-2-matthew.brost@intel.com Signed-off-by: Lucas De Marchi (cherry picked from commit 37c15c4aae1fe3f67efd2641db8d8c25c2d524ab) Signed-off-by: Lucas De Marchi --- drivers/gpu/drm/xe/xe_device.c | 11 ++++++++++- drivers/gpu/drm/xe/xe_device_types.h | 3 +++ drivers/gpu/drm/xe/xe_preempt_fence.c | 2 +- 3 files changed, 14 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/gpu/drm/xe/xe_device.c b/drivers/gpu/drm/xe/xe_device.c index ca85e81fdb44..d32ff3857e65 100644 --- a/drivers/gpu/drm/xe/xe_device.c +++ b/drivers/gpu/drm/xe/xe_device.c @@ -193,6 +193,9 @@ static void xe_device_destroy(struct drm_device *dev, void *dummy) { struct xe_device *xe = to_xe_device(dev); + if (xe->preempt_fence_wq) + destroy_workqueue(xe->preempt_fence_wq); + if (xe->ordered_wq) destroy_workqueue(xe->ordered_wq); @@ -258,9 +261,15 @@ struct xe_device *xe_device_create(struct pci_dev *pdev, INIT_LIST_HEAD(&xe->pinned.external_vram); INIT_LIST_HEAD(&xe->pinned.evicted); + xe->preempt_fence_wq = alloc_ordered_workqueue("xe-preempt-fence-wq", 0); xe->ordered_wq = alloc_ordered_workqueue("xe-ordered-wq", 0); xe->unordered_wq = alloc_workqueue("xe-unordered-wq", 0, 0); - if (!xe->ordered_wq || !xe->unordered_wq) { + if (!xe->ordered_wq || !xe->unordered_wq || + !xe->preempt_fence_wq) { + /* + * Cleanup done in xe_device_destroy via + * drmm_add_action_or_reset register above + */ drm_err(&xe->drm, "Failed to allocate xe workqueues\n"); err = -ENOMEM; goto err; diff --git a/drivers/gpu/drm/xe/xe_device_types.h b/drivers/gpu/drm/xe/xe_device_types.h index 9785eef2e5a4..8e3a222b41cf 100644 --- a/drivers/gpu/drm/xe/xe_device_types.h +++ b/drivers/gpu/drm/xe/xe_device_types.h @@ -363,6 +363,9 @@ struct xe_device { /** @ufence_wq: user fence wait queue */ wait_queue_head_t ufence_wq; + /** @preempt_fence_wq: used to serialize preempt fences */ + struct workqueue_struct *preempt_fence_wq; + /** @ordered_wq: used to serialize compute mode resume */ struct workqueue_struct *ordered_wq; diff --git a/drivers/gpu/drm/xe/xe_preempt_fence.c b/drivers/gpu/drm/xe/xe_preempt_fence.c index 7bce2a332603..7d50c6e89d8e 100644 --- a/drivers/gpu/drm/xe/xe_preempt_fence.c +++ b/drivers/gpu/drm/xe/xe_preempt_fence.c @@ -49,7 +49,7 @@ static bool preempt_fence_enable_signaling(struct dma_fence *fence) struct xe_exec_queue *q = pfence->q; pfence->error = q->ops->suspend(q); - queue_work(system_unbound_wq, &pfence->preempt_work); + queue_work(q->vm->xe->preempt_fence_wq, &pfence->preempt_work); return true; } -- cgit v1.2.3