drm/xe: Rework rebinding
authorThomas Hellström <thomas.hellstrom@linux.intel.com>
Wed, 27 Mar 2024 09:11:34 +0000 (10:11 +0100)
committerLucas De Marchi <lucas.demarchi@intel.com>
Thu, 4 Apr 2024 13:32:26 +0000 (08:32 -0500)
Instead of handling the vm's rebind fence separately,
which is error prone if they are not strictly ordered,
attach rebind fences as kernel fences to the vm's resv.

Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: <stable@vger.kernel.org> # v6.8+
Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240327091136.3271-3-thomas.hellstrom@linux.intel.com
(cherry picked from commit 5a091aff50b780ae29c7faf70a7a6c21c98a54c4)
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
drivers/gpu/drm/xe/xe_exec.c
drivers/gpu/drm/xe/xe_pt.c
drivers/gpu/drm/xe/xe_vm.c
drivers/gpu/drm/xe/xe_vm.h
drivers/gpu/drm/xe/xe_vm_types.h

index 826c8b3..79469b7 100644 (file)
@@ -152,7 +152,6 @@ int xe_exec_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
        struct drm_exec *exec = &vm_exec.exec;
        u32 i, num_syncs = 0, num_ufence = 0;
        struct xe_sched_job *job;
-       struct dma_fence *rebind_fence;
        struct xe_vm *vm;
        bool write_locked, skip_retry = false;
        ktime_t end = 0;
@@ -294,35 +293,11 @@ retry:
         * Rebind any invalidated userptr or evicted BOs in the VM, non-compute
         * VM mode only.
         */
-       rebind_fence = xe_vm_rebind(vm, false);
-       if (IS_ERR(rebind_fence)) {
-               err = PTR_ERR(rebind_fence);
+       err = xe_vm_rebind(vm, false);
+       if (err)
                goto err_put_job;
-       }
-
-       /*
-        * We store the rebind_fence in the VM so subsequent execs don't get
-        * scheduled before the rebinds of userptrs / evicted BOs is complete.
-        */
-       if (rebind_fence) {
-               dma_fence_put(vm->rebind_fence);
-               vm->rebind_fence = rebind_fence;
-       }
-       if (vm->rebind_fence) {
-               if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,
-                            &vm->rebind_fence->flags)) {
-                       dma_fence_put(vm->rebind_fence);
-                       vm->rebind_fence = NULL;
-               } else {
-                       dma_fence_get(vm->rebind_fence);
-                       err = drm_sched_job_add_dependency(&job->drm,
-                                                          vm->rebind_fence);
-                       if (err)
-                               goto err_put_job;
-               }
-       }
 
-       /* Wait behind munmap style rebinds */
+       /* Wait behind rebinds */
        if (!xe_vm_in_lr_mode(vm)) {
                err = drm_sched_job_add_resv_dependencies(&job->drm,
                                                          xe_vm_resv(vm),
index 9fd65f5..5fc4ad1 100644 (file)
@@ -1299,7 +1299,7 @@ __xe_pt_bind_vma(struct xe_tile *tile, struct xe_vma *vma, struct xe_exec_queue
                }
 
                /* add shared fence now for pagetable delayed destroy */
-               dma_resv_add_fence(xe_vm_resv(vm), fence, !rebind &&
+               dma_resv_add_fence(xe_vm_resv(vm), fence, rebind ||
                                   last_munmap_rebind ?
                                   DMA_RESV_USAGE_KERNEL :
                                   DMA_RESV_USAGE_BOOKKEEP);
index f88faef..3b97e9c 100644 (file)
@@ -522,7 +522,6 @@ static void preempt_rebind_work_func(struct work_struct *w)
 {
        struct xe_vm *vm = container_of(w, struct xe_vm, preempt.rebind_work);
        struct drm_exec exec;
-       struct dma_fence *rebind_fence;
        unsigned int fence_count = 0;
        LIST_HEAD(preempt_fences);
        ktime_t end = 0;
@@ -568,18 +567,11 @@ retry:
        if (err)
                goto out_unlock;
 
-       rebind_fence = xe_vm_rebind(vm, true);
-       if (IS_ERR(rebind_fence)) {
-               err = PTR_ERR(rebind_fence);
+       err = xe_vm_rebind(vm, true);
+       if (err)
                goto out_unlock;
-       }
-
-       if (rebind_fence) {
-               dma_fence_wait(rebind_fence, false);
-               dma_fence_put(rebind_fence);
-       }
 
-       /* Wait on munmap style VM unbinds */
+       /* Wait on rebinds and munmap style VM unbinds */
        wait = dma_resv_wait_timeout(xe_vm_resv(vm),
                                     DMA_RESV_USAGE_KERNEL,
                                     false, MAX_SCHEDULE_TIMEOUT);
@@ -773,14 +765,14 @@ xe_vm_bind_vma(struct xe_vma *vma, struct xe_exec_queue *q,
               struct xe_sync_entry *syncs, u32 num_syncs,
               bool first_op, bool last_op);
 
-struct dma_fence *xe_vm_rebind(struct xe_vm *vm, bool rebind_worker)
+int xe_vm_rebind(struct xe_vm *vm, bool rebind_worker)
 {
-       struct dma_fence *fence = NULL;
+       struct dma_fence *fence;
        struct xe_vma *vma, *next;
 
        lockdep_assert_held(&vm->lock);
        if (xe_vm_in_lr_mode(vm) && !rebind_worker)
-               return NULL;
+               return 0;
 
        xe_vm_assert_held(vm);
        list_for_each_entry_safe(vma, next, &vm->rebind_list,
@@ -788,17 +780,17 @@ struct dma_fence *xe_vm_rebind(struct xe_vm *vm, bool rebind_worker)
                xe_assert(vm->xe, vma->tile_present);
 
                list_del_init(&vma->combined_links.rebind);
-               dma_fence_put(fence);
                if (rebind_worker)
                        trace_xe_vma_rebind_worker(vma);
                else
                        trace_xe_vma_rebind_exec(vma);
                fence = xe_vm_bind_vma(vma, NULL, NULL, 0, false, false);
                if (IS_ERR(fence))
-                       return fence;
+                       return PTR_ERR(fence);
+               dma_fence_put(fence);
        }
 
-       return fence;
+       return 0;
 }
 
 static void xe_vma_free(struct xe_vma *vma)
@@ -1589,7 +1581,6 @@ static void vm_destroy_work_func(struct work_struct *w)
                XE_WARN_ON(vm->pt_root[id]);
 
        trace_xe_vm_free(vm);
-       dma_fence_put(vm->rebind_fence);
        kfree(vm);
 }
 
index 6df1f1c..4853354 100644 (file)
@@ -207,7 +207,7 @@ int __xe_vm_userptr_needs_repin(struct xe_vm *vm);
 
 int xe_vm_userptr_check_repin(struct xe_vm *vm);
 
-struct dma_fence *xe_vm_rebind(struct xe_vm *vm, bool rebind_worker);
+int xe_vm_rebind(struct xe_vm *vm, bool rebind_worker);
 
 int xe_vm_invalidate_vma(struct xe_vma *vma);
 
index 5747f13..badf394 100644 (file)
@@ -177,9 +177,6 @@ struct xe_vm {
         */
        struct list_head rebind_list;
 
-       /** @rebind_fence: rebind fence from execbuf */
-       struct dma_fence *rebind_fence;
-
        /**
         * @destroy_work: worker to destroy VM, needed as a dma_fence signaling
         * from an irq context can be last put and the destroy needs to be able