Enables users to update SVM's default granularity, used in
buffer migration and handling of recoverable page faults.
Param value is set in terms of log(numPages(buffer)),
e.g. 9 for a 2 MIB buffer
Signed-off-by: Ramesh Errabolu <Ramesh.Errabolu@xxxxxxx>
---
drivers/gpu/drm/amd/amdgpu/amdgpu.h | 1 +
drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 17 +++++++++++++++++
drivers/gpu/drm/amd/amdkfd/kfd_priv.h | 6 ++++++
drivers/gpu/drm/amd/amdkfd/kfd_svm.c | 25 +++++++++++++++----------
4 files changed, 39 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index e8c284aea1f2..8eb934af02f2 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -237,6 +237,7 @@ extern int sched_policy;
extern bool debug_evictions;
extern bool no_system_mem_limit;
extern int halt_if_hws_hang;
+extern uint amdgpu_svm_default_granularity;
#else
static const int __maybe_unused sched_policy = KFD_SCHED_POLICY_HWS;
static const bool __maybe_unused debug_evictions; /* = false */
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
index b9529948f2b2..442039436cb3 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
@@ -169,6 +169,16 @@ uint amdgpu_sdma_phase_quantum = 32;
char *amdgpu_disable_cu;
char *amdgpu_virtual_display;
bool enforce_isolation;
+
+/* Specifies the default granularity for SVM, used in buffer
+ * migration and restoration of backing memory when handling
+ * recoverable page faults.
+ *
+ * The value is given as log(numPages(buffer)); for a 2 MiB
+ * buffer it computes to be 9
+ */
+uint amdgpu_svm_default_granularity = 9;
+
/*
* OverDrive(bit 14) disabled by default
* GFX DCS(bit 19) disabled by default
@@ -320,6 +330,13 @@ module_param_named(pcie_gen2, amdgpu_pcie_gen2, int, 0444);
MODULE_PARM_DESC(msi, "MSI support (1 = enable, 0 = disable, -1 = auto)");
module_param_named(msi, amdgpu_msi, int, 0444);
+/**
+ * DOC: svm_default_granularity (uint)
+ * Used in buffer migration and handling of recoverable page faults
+ */
+MODULE_PARM_DESC(svm_default_granularity, "SVM's default granularity in log(2^Pages), default 9 = 2^9 = 2 MiB");
+module_param_named(svm_default_granularity, amdgpu_svm_default_granularity, uint, 0644);
+
/**
* DOC: lockup_timeout (string)
* Set GPU scheduler timeout value in ms.
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
index 9ae9abc6eb43..d6530febabad 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
@@ -868,6 +868,12 @@ struct svm_range_list {
struct task_struct *faulting_task;
/* check point ts decides if page fault recovery need be dropped */
uint64_t checkpoint_ts[MAX_GPU_INSTANCE];
+
+ /* Default granularity to use in buffer migration
+ * and restoration of backing memory while handling
+ * recoverable page faults
+ */
+ uint8_t default_granularity;
};
/* Process data */
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index b44dec90969f..624bfe317c9c 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -309,12 +309,13 @@ static void svm_range_free(struct svm_range *prange, bool do_unmap)
}
static void
-svm_range_set_default_attributes(int32_t *location, int32_t *prefetch_loc,
- uint8_t *granularity, uint32_t *flags)
+svm_range_set_default_attributes(struct svm_range_list *svms,
+ int32_t *location, uint8_t *granularity,
+ int32_t *prefetch_loc, uint32_t *flags)
{
*location = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
*prefetch_loc = KFD_IOCTL_SVM_LOCATION_UNDEFINED;
- *granularity = 9;
+ *granularity = svms->default_granularity;
*flags =
KFD_IOCTL_SVM_FLAG_HOST_ACCESS | KFD_IOCTL_SVM_FLAG_COHERENT;
}
@@ -358,9 +359,8 @@ svm_range *svm_range_new(struct svm_range_list *svms, uint64_t start,
bitmap_copy(prange->bitmap_access, svms->bitmap_supported,
MAX_GPU_INSTANCE);
- svm_range_set_default_attributes(&prange->preferred_loc,
- &prange->prefetch_loc,
- &prange->granularity, &prange->flags);
+ svm_range_set_default_attributes(svms, &prange->preferred_loc,
+ &prange->granularity, &prange->prefetch_loc, &prange->flags);
pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last);
@@ -2694,9 +2694,10 @@ svm_range_get_range_boundaries(struct kfd_process *p, int64_t addr,
*is_heap_stack = vma_is_initial_heap(vma) || vma_is_initial_stack(vma);
start_limit = max(vma->vm_start >> PAGE_SHIFT,
- (unsigned long)ALIGN_DOWN(addr, 2UL << 8));
+ (unsigned long)ALIGN_DOWN(addr, 1UL << p->svms.default_granularity));
end_limit = min(vma->vm_end >> PAGE_SHIFT,
- (unsigned long)ALIGN(addr + 1, 2UL << 8));
+ (unsigned long)ALIGN(addr + 1, 1UL << p->svms.default_granularity));
+
/* First range that starts after the fault address */
node = interval_tree_iter_first(&p->svms.objects, addr + 1, ULONG_MAX);
if (node) {
@@ -3240,6 +3241,10 @@ int svm_range_list_init(struct kfd_process *p)
if (KFD_IS_SVM_API_SUPPORTED(p->pdds[i]->dev->adev))
bitmap_set(svms->bitmap_supported, i, 1);
+ /* Update default granularity to one bound by user/driver */
+ svms->default_granularity = min_t(u8, amdgpu_svm_default_granularity, 0x1B);
+ pr_debug("Default SVM Granularity to use: %d\n", svms->default_granularity);
+
return 0;
}
@@ -3767,8 +3772,8 @@ svm_range_get_attr(struct kfd_process *p, struct mm_struct *mm,
node = interval_tree_iter_first(&svms->objects, start, last);
if (!node) {
pr_debug("range attrs not found return default values\n");
- svm_range_set_default_attributes(&location, &prefetch_loc,
- &granularity, &flags_and);
+ svm_range_set_default_attributes(svms, &location,
+ &granularity, &prefetch_loc, &flags_and);
flags_or = flags_and;
if (p->xnack_enabled)
bitmap_copy(bitmap_access, svms->bitmap_supported,
--
2.34.1
