Files
linux/drivers/gpu/drm/xe/xe_svm.h
Matthew Brost 794f5493f5 drm/xe: Strict migration policy for atomic SVM faults
Mixing GPU and CPU atomics does not work unless a strict migration
policy of GPU atomics must be device memory. Enforce a policy of must be
in VRAM with a retry loop of 3 attempts, if retry loop fails abort
fault.

Removing always_migrate_to_vram modparam as we now have real migration
policy.

v2:
 - Only retry migration on atomics
 - Drop alway migrate modparam
v3:
 - Only set vram_only on DGFX (Himal)
 - Bail on get_pages failure if vram_only and retry count exceeded (Himal)
 - s/vram_only/devmem_only
 - Update xe_svm_range_is_valid to accept devmem_only argument
v4:
 - Fix logic bug get_pages failure
v5:
 - Fix commit message (Himal)
 - Mention removing always_migrate_to_vram in commit message (Lucas)
 - Fix xe_svm_range_is_valid to check for devmem pages
 - Bail on devmem_only && !migrate_devmem (Thomas)
v6:
 - Add READ_ONCE barriers for opportunistic checks (Thomas)
 - Pair READ_ONCE with WRITE_ONCE (Thomas)
v7:
 - Adjust comments (Thomas)

Fixes: 2f118c9491 ("drm/xe: Add SVM VRAM migration")
Cc: stable@vger.kernel.org
Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Acked-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://lore.kernel.org/r/20250512135500.1405019-3-matthew.brost@intel.com
(cherry picked from commit a9ac0fa455)
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
2025-05-14 09:03:29 -07:00

154 lines
3.2 KiB
C

/* SPDX-License-Identifier: MIT */
/*
* Copyright © 2024 Intel Corporation
*/
#ifndef _XE_SVM_H_
#define _XE_SVM_H_
#include <drm/drm_pagemap.h>
#include <drm/drm_gpusvm.h>
#define XE_INTERCONNECT_VRAM DRM_INTERCONNECT_DRIVER
struct xe_bo;
struct xe_vram_region;
struct xe_tile;
struct xe_vm;
struct xe_vma;
/** struct xe_svm_range - SVM range */
struct xe_svm_range {
/** @base: base drm_gpusvm_range */
struct drm_gpusvm_range base;
/**
* @garbage_collector_link: Link into VM's garbage collect SVM range
* list. Protected by VM's garbage collect lock.
*/
struct list_head garbage_collector_link;
/**
* @tile_present: Tile mask of binding is present for this range.
* Protected by GPU SVM notifier lock.
*/
u8 tile_present;
/**
* @tile_invalidated: Tile mask of binding is invalidated for this
* range. Protected by GPU SVM notifier lock.
*/
u8 tile_invalidated;
};
#if IS_ENABLED(CONFIG_DRM_GPUSVM)
/**
* xe_svm_range_pages_valid() - SVM range pages valid
* @range: SVM range
*
* Return: True if SVM range pages are valid, False otherwise
*/
static inline bool xe_svm_range_pages_valid(struct xe_svm_range *range)
{
return drm_gpusvm_range_pages_valid(range->base.gpusvm, &range->base);
}
int xe_devm_add(struct xe_tile *tile, struct xe_vram_region *vr);
int xe_svm_init(struct xe_vm *vm);
void xe_svm_fini(struct xe_vm *vm);
void xe_svm_close(struct xe_vm *vm);
int xe_svm_handle_pagefault(struct xe_vm *vm, struct xe_vma *vma,
struct xe_tile *tile, u64 fault_addr,
bool atomic);
bool xe_svm_has_mapping(struct xe_vm *vm, u64 start, u64 end);
int xe_svm_bo_evict(struct xe_bo *bo);
void xe_svm_range_debug(struct xe_svm_range *range, const char *operation);
void xe_svm_flush(struct xe_vm *vm);
#else
static inline bool xe_svm_range_pages_valid(struct xe_svm_range *range)
{
return false;
}
static inline
int xe_devm_add(struct xe_tile *tile, struct xe_vram_region *vr)
{
return 0;
}
static inline
int xe_svm_init(struct xe_vm *vm)
{
return 0;
}
static inline
void xe_svm_fini(struct xe_vm *vm)
{
}
static inline
void xe_svm_close(struct xe_vm *vm)
{
}
static inline
int xe_svm_handle_pagefault(struct xe_vm *vm, struct xe_vma *vma,
struct xe_tile *tile, u64 fault_addr,
bool atomic)
{
return 0;
}
static inline
bool xe_svm_has_mapping(struct xe_vm *vm, u64 start, u64 end)
{
return false;
}
static inline
int xe_svm_bo_evict(struct xe_bo *bo)
{
return 0;
}
static inline
void xe_svm_range_debug(struct xe_svm_range *range, const char *operation)
{
}
static inline void xe_svm_flush(struct xe_vm *vm)
{
}
#endif
/**
* xe_svm_range_has_dma_mapping() - SVM range has DMA mapping
* @range: SVM range
*
* Return: True if SVM range has a DMA mapping, False otherwise
*/
static inline bool xe_svm_range_has_dma_mapping(struct xe_svm_range *range)
{
lockdep_assert_held(&range->base.gpusvm->notifier_lock);
return range->base.flags.has_dma_mapping;
}
#define xe_svm_assert_in_notifier(vm__) \
lockdep_assert_held_write(&(vm__)->svm.gpusvm.notifier_lock)
#define xe_svm_notifier_lock(vm__) \
drm_gpusvm_notifier_lock(&(vm__)->svm.gpusvm)
#define xe_svm_notifier_unlock(vm__) \
drm_gpusvm_notifier_unlock(&(vm__)->svm.gpusvm)
#endif