Ensure GPU can make forward progress on an atomic SVM GPU fault by
giving the GPU a timeslice of 10 MS.
Signed-off-by: Matthew Brost <matthew.br...@intel.com>
---
drivers/gpu/drm/drm_gpusvm.c | 9 +++++++++
drivers/gpu/drm/xe/xe_svm.c | 1 +
include/drm/drm_gpusvm.h | 5 +++++
3 files changed, 15 insertions(+)
diff --git a/drivers/gpu/drm/drm_gpusvm.c b/drivers/gpu/drm/drm_gpusvm.c
index e7d4ada21560..28e5755aad92 100644
--- a/drivers/gpu/drm/drm_gpusvm.c
+++ b/drivers/gpu/drm/drm_gpusvm.c
@@ -1770,6 +1770,8 @@ int drm_gpusvm_migrate_to_devmem(struct drm_gpusvm
*gpusvm,
goto err_finalize;
/* Upon success bind devmem allocation to range and zdd */
+ devmem_allocation->timeslice_expiration = get_jiffies_64() +
+ msecs_to_jiffies(ctx->timeslice_ms);
zdd->devmem_allocation = devmem_allocation; /* Owns ref */
err_finalize:
@@ -1990,6 +1992,13 @@ static int __drm_gpusvm_migrate_to_ram(struct
vm_area_struct *vas,
void *buf;
int i, err = 0;
+ if (page) {
+ zdd = page->zone_device_data;
+ if (time_before64(get_jiffies_64(),
+ zdd->devmem_allocation->timeslice_expiration))
+ return 0;
+ }
+
start = ALIGN_DOWN(fault_addr, size);
end = ALIGN(fault_addr + 1, size);
diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c
index ec61af659a13..121e39a2dd38 100644
--- a/drivers/gpu/drm/xe/xe_svm.c
+++ b/drivers/gpu/drm/xe/xe_svm.c
@@ -780,6 +780,7 @@ int xe_svm_handle_pagefault(struct xe_vm *vm, struct xe_vma
*vma,
.check_pages_threshold = IS_DGFX(vm->xe) &&
IS_ENABLED(CONFIG_DRM_XE_DEVMEM_MIRROR) ? SZ_64K : 0,
.vram_only = atomic,
+ .timeslice_ms = atomic ? 10 : 0,
};
struct xe_svm_range *range;
struct drm_gpusvm_range *r;
diff --git a/include/drm/drm_gpusvm.h b/include/drm/drm_gpusvm.h
index 8093cc6ab1f4..d301c94d90cd 100644
--- a/include/drm/drm_gpusvm.h
+++ b/include/drm/drm_gpusvm.h
@@ -89,6 +89,7 @@ struct drm_gpusvm_devmem_ops {
* @ops: Pointer to the operations structure for GPU SVM device memory
* @dpagemap: The struct drm_pagemap of the pages this allocation belongs to.
* @size: Size of device memory allocation
+ * @timeslice_expiration: Timeslice expiration in jiffies
*/
struct drm_gpusvm_devmem {
struct device *dev;
@@ -97,6 +98,7 @@ struct drm_gpusvm_devmem {
const struct drm_gpusvm_devmem_ops *ops;
struct drm_pagemap *dpagemap;
size_t size;
+ u64 timeslice_expiration;
};
/**
@@ -283,6 +285,8 @@ struct drm_gpusvm {
* @check_pages_threshold: Check CPU pages for present if chunk is less than or
* equal to threshold. If not present, reduce chunk
* size.
+ * @timeslice_ms: The timeslice MS which in minimum time a piece of memory
+ * remains with either exclusive GPU or CPU access.
* @in_notifier: entering from a MMU notifier
* @read_only: operating on read-only memory
* @devmem_possible: possible to use device memory
@@ -292,6 +296,7 @@ struct drm_gpusvm {
*/
struct drm_gpusvm_ctx {
unsigned long check_pages_threshold;
+ unsigned long timeslice_ms;
unsigned int in_notifier :1;
unsigned int read_only :1;
unsigned int devmem_possible :1;
--
2.34.1
