drm/xe: Use reserved copy engine for user binds on faulting devices

[ Upstream commit 852856e3b6f679c694dd5ec41e5a3c11aa46640b ]

User binds map to engines with can fault, faults depend on user binds
completion, thus we can deadlock. Avoid this by using reserved copy
engine for user binds on faulting devices.

While we are here, normalize bind queue creation with a helper.

v2:
 - Pass in extensions to bind queue creation (CI)
v3:
 - s/resevered/reserved (Lucas)
 - Fix NULL hwe check (Jonathan)

Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240816034033.53837-1-matthew.brost@intel.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/xe/xe_exec_queue.c b/drivers/gpu/drm/xe/xe_exec_queue.c
index ddc22a8d9bf5fa35090140bde24a33af5e6827a1..c2953ddbd16e130eb9a2cb45a130bde3fe8fbe71 100644 (file)
--- a/drivers/gpu/drm/xe/xe_exec_queue.c
+++ b/drivers/gpu/drm/xe/xe_exec_queue.c
@@ -166,7 +166,8 @@ err_post_alloc:
 
 struct xe_exec_queue *xe_exec_queue_create_class(struct xe_device *xe, struct xe_gt *gt,
                                                 struct xe_vm *vm,
-                                                enum xe_engine_class class, u32 flags)
+                                                enum xe_engine_class class,
+                                                u32 flags, u64 extensions)
 {
        struct xe_hw_engine *hwe, *hwe0 = NULL;
        enum xe_hw_engine_id id;
@@ -186,7 +187,54 @@ struct xe_exec_queue *xe_exec_queue_create_class(struct xe_device *xe, struct xe
        if (!logical_mask)
                return ERR_PTR(-ENODEV);
 
-       return xe_exec_queue_create(xe, vm, logical_mask, 1, hwe0, flags, 0);
+       return xe_exec_queue_create(xe, vm, logical_mask, 1, hwe0, flags, extensions);
+}
+
+/**
+ * xe_exec_queue_create_bind() - Create bind exec queue.
+ * @xe: Xe device.
+ * @tile: tile which bind exec queue belongs to.
+ * @flags: exec queue creation flags
+ * @extensions: exec queue creation extensions
+ *
+ * Normalize bind exec queue creation. Bind exec queue is tied to migration VM
+ * for access to physical memory required for page table programming. On a
+ * faulting devices the reserved copy engine instance must be used to avoid
+ * deadlocking (user binds cannot get stuck behind faults as kernel binds which
+ * resolve faults depend on user binds). On non-faulting devices any copy engine
+ * can be used.
+ *
+ * Returns exec queue on success, ERR_PTR on failure
+ */
+struct xe_exec_queue *xe_exec_queue_create_bind(struct xe_device *xe,
+                                               struct xe_tile *tile,
+                                               u32 flags, u64 extensions)
+{
+       struct xe_gt *gt = tile->primary_gt;
+       struct xe_exec_queue *q;
+       struct xe_vm *migrate_vm;
+
+       migrate_vm = xe_migrate_get_vm(tile->migrate);
+       if (xe->info.has_usm) {
+               struct xe_hw_engine *hwe = xe_gt_hw_engine(gt,
+                                                          XE_ENGINE_CLASS_COPY,
+                                                          gt->usm.reserved_bcs_instance,
+                                                          false);
+
+               if (!hwe)
+                       return ERR_PTR(-EINVAL);
+
+               q = xe_exec_queue_create(xe, migrate_vm,
+                                        BIT(hwe->logical_instance), 1, hwe,
+                                        flags, extensions);
+       } else {
+               q = xe_exec_queue_create_class(xe, gt, migrate_vm,
+                                              XE_ENGINE_CLASS_COPY, flags,
+                                              extensions);
+       }
+       xe_vm_put(migrate_vm);
+
+       return q;
 }
 
 void xe_exec_queue_destroy(struct kref *ref)
@@ -418,34 +466,6 @@ static int exec_queue_user_extensions(struct xe_device *xe, struct xe_exec_queue
        return 0;
 }
 
-static u32 bind_exec_queue_logical_mask(struct xe_device *xe, struct xe_gt *gt,
-                                       struct drm_xe_engine_class_instance *eci,
-                                       u16 width, u16 num_placements)
-{
-       struct xe_hw_engine *hwe;
-       enum xe_hw_engine_id id;
-       u32 logical_mask = 0;
-
-       if (XE_IOCTL_DBG(xe, width != 1))
-               return 0;
-       if (XE_IOCTL_DBG(xe, num_placements != 1))
-               return 0;
-       if (XE_IOCTL_DBG(xe, eci[0].engine_instance != 0))
-               return 0;
-
-       eci[0].engine_class = DRM_XE_ENGINE_CLASS_COPY;
-
-       for_each_hw_engine(hwe, gt, id) {
-               if (xe_hw_engine_is_reserved(hwe))
-                       continue;
-
-               if (hwe->class == XE_ENGINE_CLASS_COPY)
-                       logical_mask |= BIT(hwe->logical_instance);
-       }
-
-       return logical_mask;
-}
-
 static u32 calc_validate_logical_mask(struct xe_device *xe, struct xe_gt *gt,
                                      struct drm_xe_engine_class_instance *eci,
                                      u16 width, u16 num_placements)
@@ -507,8 +527,9 @@ int xe_exec_queue_create_ioctl(struct drm_device *dev, void *data,
        struct drm_xe_engine_class_instance __user *user_eci =
                u64_to_user_ptr(args->instances);
        struct xe_hw_engine *hwe;
-       struct xe_vm *vm, *migrate_vm;
+       struct xe_vm *vm;
        struct xe_gt *gt;
+       struct xe_tile *tile;
        struct xe_exec_queue *q = NULL;
        u32 logical_mask;
        u32 id;
@@ -533,37 +554,20 @@ int xe_exec_queue_create_ioctl(struct drm_device *dev, void *data,
                return -EINVAL;
 
        if (eci[0].engine_class == DRM_XE_ENGINE_CLASS_VM_BIND) {
-               for_each_gt(gt, xe, id) {
-                       struct xe_exec_queue *new;
-                       u32 flags;
-
-                       if (xe_gt_is_media_type(gt))
-                               continue;
-
-                       eci[0].gt_id = gt->info.id;
-                       logical_mask = bind_exec_queue_logical_mask(xe, gt, eci,
-                                                                   args->width,
-                                                                   args->num_placements);
-                       if (XE_IOCTL_DBG(xe, !logical_mask))
-                               return -EINVAL;
-
-                       hwe = xe_hw_engine_lookup(xe, eci[0]);
-                       if (XE_IOCTL_DBG(xe, !hwe))
-                               return -EINVAL;
-
-                       /* The migration vm doesn't hold rpm ref */
-                       xe_pm_runtime_get_noresume(xe);
-
-                       flags = EXEC_QUEUE_FLAG_VM | (id ? EXEC_QUEUE_FLAG_BIND_ENGINE_CHILD : 0);
+               if (XE_IOCTL_DBG(xe, args->width != 1) ||
+                   XE_IOCTL_DBG(xe, args->num_placements != 1) ||
+                   XE_IOCTL_DBG(xe, eci[0].engine_instance != 0))
+                       return -EINVAL;
 
-                       migrate_vm = xe_migrate_get_vm(gt_to_tile(gt)->migrate);
-                       new = xe_exec_queue_create(xe, migrate_vm, logical_mask,
-                                                  args->width, hwe, flags,
-                                                  args->extensions);
+               for_each_tile(tile, xe, id) {
+                       struct xe_exec_queue *new;
+                       u32 flags = EXEC_QUEUE_FLAG_VM;
 
-                       xe_pm_runtime_put(xe); /* now held by engine */
+                       if (id)
+                               flags |= EXEC_QUEUE_FLAG_BIND_ENGINE_CHILD;
 
-                       xe_vm_put(migrate_vm);
+                       new = xe_exec_queue_create_bind(xe, tile, flags,
+                                                       args->extensions);
                        if (IS_ERR(new)) {
                                err = PTR_ERR(new);
                                if (q)

diff --git a/drivers/gpu/drm/xe/xe_exec_queue.h b/drivers/gpu/drm/xe/xe_exec_queue.h
index 289a3a51d2a21b1f5c55094ca941851d1d14e358..f4ba8897763f8a3aa6aabe8d9c991bcc42bb4c85 100644 (file)
--- a/drivers/gpu/drm/xe/xe_exec_queue.h
+++ b/drivers/gpu/drm/xe/xe_exec_queue.h
@@ -20,7 +20,11 @@ struct xe_exec_queue *xe_exec_queue_create(struct xe_device *xe, struct xe_vm *v
                                           u64 extensions);
 struct xe_exec_queue *xe_exec_queue_create_class(struct xe_device *xe, struct xe_gt *gt,
                                                 struct xe_vm *vm,
-                                                enum xe_engine_class class, u32 flags);
+                                                enum xe_engine_class class,
+                                                u32 flags, u64 extensions);
+struct xe_exec_queue *xe_exec_queue_create_bind(struct xe_device *xe,
+                                               struct xe_tile *tile,
+                                               u32 flags, u64 extensions);
 
 void xe_exec_queue_fini(struct xe_exec_queue *q);
 void xe_exec_queue_destroy(struct kref *ref);

diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c
index c9f5673353ee3e14bad21ee49ffb7a477528eb41..a849c48d8ac90f36d92d104313e1492b7345ce1b 100644 (file)
--- a/drivers/gpu/drm/xe/xe_migrate.c
+++ b/drivers/gpu/drm/xe/xe_migrate.c
@@ -404,7 +404,7 @@ struct xe_migrate *xe_migrate_init(struct xe_tile *tile)
                m->q = xe_exec_queue_create_class(xe, primary_gt, vm,
                                                  XE_ENGINE_CLASS_COPY,
                                                  EXEC_QUEUE_FLAG_KERNEL |
-                                                 EXEC_QUEUE_FLAG_PERMANENT);
+                                                 EXEC_QUEUE_FLAG_PERMANENT, 0);
        }
        if (IS_ERR(m->q)) {
                xe_vm_close_and_put(vm);

diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index 50e8fc49ba6c154fb45a5b9cd1ee51522fb84edd..b49bee0dfac5da481bba23c354b873ac7d79e2ef 100644 (file)
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -1412,19 +1412,13 @@ struct xe_vm *xe_vm_create(struct xe_device *xe, u32 flags)
        /* Kernel migration VM shouldn't have a circular loop.. */
        if (!(flags & XE_VM_FLAG_MIGRATION)) {
                for_each_tile(tile, xe, id) {
-                       struct xe_gt *gt = tile->primary_gt;
-                       struct xe_vm *migrate_vm;
                        struct xe_exec_queue *q;
                        u32 create_flags = EXEC_QUEUE_FLAG_VM;
 
                        if (!vm->pt_root[id])
                                continue;
 
-                       migrate_vm = xe_migrate_get_vm(tile->migrate);
-                       q = xe_exec_queue_create_class(xe, gt, migrate_vm,
-                                                      XE_ENGINE_CLASS_COPY,
-                                                      create_flags);
-                       xe_vm_put(migrate_vm);
+                       q = xe_exec_queue_create_bind(xe, tile, create_flags, 0);
                        if (IS_ERR(q)) {
                                err = PTR_ERR(q);
                                goto err_close;