drm/xe: Rework rebinding

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>

diff --git a/drivers/gpu/drm/xe/xe_exec.c b/drivers/gpu/drm/xe/xe_exec.c
index 826c8b389672502dfebd6e89c6c1997bf8f0c9a2..79469b76a8beef79ca04bf268bfffe495825d418 100644 (file)
--- a/drivers/gpu/drm/xe/xe_exec.c
+++ b/drivers/gpu/drm/xe/xe_exec.c
@@ -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),

diff --git a/drivers/gpu/drm/xe/xe_pt.c b/drivers/gpu/drm/xe/xe_pt.c
index 9fd65f5d3d8036ec02866fb985da78a2b706da00..5fc4ad1e42981a6cbe510fcfbbecd9786c718e49 100644 (file)
--- a/drivers/gpu/drm/xe/xe_pt.c
+++ b/drivers/gpu/drm/xe/xe_pt.c
@@ -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);

diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index f88faef4142bde018f336d33d3e2eed726a4bc29..3b97e9c9260913ccb73ceef3a7f7bad92f7f2994 100644 (file)
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -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);
 }
 

diff --git a/drivers/gpu/drm/xe/xe_vm.h b/drivers/gpu/drm/xe/xe_vm.h
index 6df1f1c7f85d98a2b948ba41ec9f1ed5a287faf0..4853354336f29a9fb92db6bd3c0b8feb9226b700 100644 (file)
--- a/drivers/gpu/drm/xe/xe_vm.h
+++ b/drivers/gpu/drm/xe/xe_vm.h
@@ -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);
 

diff --git a/drivers/gpu/drm/xe/xe_vm_types.h b/drivers/gpu/drm/xe/xe_vm_types.h
index 5747f136d24d1f3790f8ae928b86e52373c4cec7..badf3945083d56723cc477b3074929a4db316753 100644 (file)
--- a/drivers/gpu/drm/xe/xe_vm_types.h
+++ b/drivers/gpu/drm/xe/xe_vm_types.h
@@ -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