[PATCH v5 04/20] drm/xe: Timeslice GPU on atomic SVM fault

[Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>]

From: Matthew Brost <matthew.brost@intel.com>

Ensure GPU can make forward progress on an atomic SVM GPU fault by
giving the GPU a timeslice of 5ms

v2:
 - Reduce timeslice to 5ms
 - Double timeslice on retry
 - Split out GPU SVM changes into independent patch

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
---
 drivers/gpu/drm/xe/xe_svm.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c
index f749ae367a8f..d5376a76cdd1 100644
--- a/drivers/gpu/drm/xe/xe_svm.c
+++ b/drivers/gpu/drm/xe/xe_svm.c
@@ -783,6 +783,8 @@ int xe_svm_handle_pagefault(struct xe_vm *vm, struct xe_vma *vma,
 			IS_ENABLED(CONFIG_DRM_XE_DEVMEM_MIRROR) ? SZ_64K : 0,
 		.devmem_only = atomic && IS_DGFX(vm->xe) &&
 			IS_ENABLED(CONFIG_DRM_XE_DEVMEM_MIRROR),
+		.timeslice_ms = atomic && IS_DGFX(vm->xe) &&
+			IS_ENABLED(CONFIG_DRM_XE_DEVMEM_MIRROR) ? 5 : 0,
 	};
 	struct xe_svm_range *range;
 	struct drm_gpusvm_range *r;
@@ -819,6 +821,7 @@ int xe_svm_handle_pagefault(struct xe_vm *vm, struct xe_vma *vma,
 	if (--migrate_try_count >= 0 &&
 	    xe_svm_range_needs_migrate_to_vram(range, vma)) {
 		err = xe_svm_alloc_vram(vm, tile, range, &ctx);
+		ctx.timeslice_ms <<= 1;	/* Double timeslice if we have to retry */
 		if (err) {
 			if (migrate_try_count || !ctx.devmem_only) {
 				drm_dbg(&vm->xe->drm,
-- 
2.34.1