Commit 4a938d38 authored by Himal Prasad Ghimiray's avatar Himal Prasad Ghimiray
Browse files

drm/xe: Merge adjacent default-attribute VMAs during garbage collection 



While restoring default memory attributes for VMAs during garbage
collection, extend the target range by checking neighboring VMAs. If
adjacent VMAs are CPU-address-mirrored and have default attributes,
include them in the mergeable range to reduce fragmentation and improve
VMA reuse.

v2
-Rebase

Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Reviewed-by: default avatarMatthew Brost <matthew.brost@intel.com>
Link: https://patch.msgid.link/20251125075628.1182481-3-himal.prasad.ghimiray@intel.com


Signed-off-by: default avatarHimal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
parent 5b12958b

drivers/gpu/drm/xe/xe_svm.c

+36 −26
Original line number Diff line number Diff line
@@ -285,19 +285,21 @@ static int __xe_svm_garbage_collector(struct xe_vm *vm, 
	return 0;

}



static int xe_svm_range_set_default_attr(struct xe_vm *vm, u64 range_start, u64 range_end)

static void xe_vma_set_default_attributes(struct xe_vma *vma)

{

	vma->attr.preferred_loc.devmem_fd = DRM_XE_PREFERRED_LOC_DEFAULT_DEVICE;

	vma->attr.preferred_loc.migration_policy = DRM_XE_MIGRATE_ALL_PAGES;

	vma->attr.pat_index = vma->attr.default_pat_index;

	vma->attr.atomic_access = DRM_XE_ATOMIC_UNDEFINED;

}



static int xe_svm_range_set_default_attr(struct xe_vm *vm, u64 start, u64 end)

{

	struct xe_vma *vma;

	struct xe_vma_mem_attr default_attr = {

		.preferred_loc = {

			.devmem_fd = DRM_XE_PREFERRED_LOC_DEFAULT_DEVICE,

			.migration_policy = DRM_XE_MIGRATE_ALL_PAGES,

		},

		.atomic_access = DRM_XE_ATOMIC_UNDEFINED,

	};

	int err = 0;

	bool has_default_attr;

	int err;



	vma = xe_vm_find_vma_by_addr(vm, range_start);

	vma = xe_vm_find_vma_by_addr(vm, start);

	if (!vma)

		return -EINVAL;
@@ -306,26 +308,34 @@ static int xe_svm_range_set_default_attr(struct xe_vm *vm, u64 range_start, u64 
		return 0;

	}



	if (xe_vma_has_default_mem_attrs(vma))

		return 0;



	vm_dbg(&vm->xe->drm, "Existing VMA start=0x%016llx, vma_end=0x%016llx",

	       xe_vma_start(vma), xe_vma_end(vma));



	if (xe_vma_start(vma) == range_start && xe_vma_end(vma) == range_end) {

		default_attr.pat_index = vma->attr.default_pat_index;

		default_attr.default_pat_index  = vma->attr.default_pat_index;

		vma->attr = default_attr;

	} else {

		vm_dbg(&vm->xe->drm, "Split VMA start=0x%016llx, vma_end=0x%016llx",

		       range_start, range_end);

		err = xe_vm_alloc_cpu_addr_mirror_vma(vm, range_start, range_end - range_start);

	has_default_attr = xe_vma_has_default_mem_attrs(vma);



	if (has_default_attr) {

		if (xe_svm_has_mapping(vm, xe_vma_start(vma), xe_vma_end(vma)))

			return 0;



		start = xe_vma_start(vma);

		end = xe_vma_end(vma);

	} else if (xe_vma_start(vma) == start && xe_vma_end(vma) == end) {

		xe_vma_set_default_attributes(vma);

	}



	xe_vm_find_cpu_addr_mirror_vma_range(vm, &start, &end);



	if (xe_vma_start(vma) == start && xe_vma_end(vma) == end && has_default_attr)

		return 0;



	vm_dbg(&vm->xe->drm, "New VMA start=0x%016llx, vma_end=0x%016llx",  start, end);



	err = xe_vm_alloc_cpu_addr_mirror_vma(vm, start, end - start);

	if (err) {

			drm_warn(&vm->xe->drm, "VMA SPLIT failed: %pe\n", ERR_PTR(err));

		drm_warn(&vm->xe->drm, "New VMA MAP failed: %pe\n", ERR_PTR(err));

		xe_vm_kill(vm, true);

		return err;

	}

	}



	/*

	 * On call from xe_svm_handle_pagefault original VMA might be changed