<html><head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> </head> <body> <div class="moz-cite-prefix">On 2024-09-03 19:24, Ramesh Errabolu wrote: </div> <blockquote type="cite" cite="mid:20240903232447.389164-1-Ramesh.Errabolu@amd.com"> <pre class="moz-quote-pre" wrap="">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 <a class="moz-txt-link-rfc2396E" href="mailto:Ramesh.Errabolu@amd.com"><Ramesh.Errabolu@amd.com></a></pre> </blockquote> With 2 below nitpicks fixed, this patch is Reviewed-by: Philip Yang <a class="moz-txt-link-rfc2396E" href="mailto:Philip.Yang@amd.com"><Philip.Yang@amd.com></a> change subject to "drm/amdkfd: Add svm_default_granularity module parameter" <blockquote type="cite" cite="mid:20240903232447.389164-1-Ramesh.Errabolu@amd.com"> <pre class="moz-quote-pre" wrap=""> --- 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 | 23 +++++++++++++++-------- 4 files changed, 39 insertions(+), 8 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..2bc2389cc7f0 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, + int32_t *prefetch_loc, uint8_t *granularity, + 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 +359,10 @@ 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, + svm_range_set_default_attributes(svms, &prange->preferred_loc, &prange->prefetch_loc, - &prange->granularity, &prange->flags); + &prange->granularity, + &prange->flags);</pre> </blockquote> unnecessary extra change. <blockquote type="cite" cite="mid:20240903232447.389164-1-Ramesh.Errabolu@amd.com"> <pre class="moz-quote-pre" wrap=""> pr_debug("svms 0x%p [0x%llx 0x%llx]\n", svms, start, last); @@ -2694,9 +2696,10 @@ 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 +3243,10 @@ 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 */</pre> </blockquote> This is more meaningful: /* 0x1B is the largest number of pages supported with 4-level paging */ Regards, Philip <blockquote type="cite" cite="mid:20240903232447.389164-1-Ramesh.Errabolu@amd.com"> <pre class="moz-quote-pre" wrap=""> + 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; } @@ -3767,7 +3774,7 @@ 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, + svm_range_set_default_attributes(svms, &location, &prefetch_loc, &granularity, &flags_and); flags_or = flags_and; if (p->xnack_enabled) </pre> </blockquote> </body> </html>