From 40ce74d1b28d38e5debc14b5a6ddd9071ae2d310 Mon Sep 17 00:00:00 2001 From: Philip Yang Date: Wed, 5 Feb 2020 17:59:15 -0500 Subject: drm/amdkfd: add svm ioctl API Add svm (shared virtual memory) ioctl data structure and API definition. The svm ioctl API is designed to be extensible in the future. All operations are provided by a single IOCTL to preserve ioctl number space. The arguments structure ends with a variable size array of attributes that can be used to set or get one or multiple attributes. Signed-off-by: Philip Yang Signed-off-by: Alex Sierra Reviewed-by: Felix Kuehling Signed-off-by: Felix Kuehling Signed-off-by: Alex Deucher --- include/uapi/linux/kfd_ioctl.h | 130 ++++++++++++++++++++++++++++++++++++++++- 1 file changed, 128 insertions(+), 2 deletions(-) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/kfd_ioctl.h b/include/uapi/linux/kfd_ioctl.h index bf5e7d7846dd..247b57baa94f 100644 --- a/include/uapi/linux/kfd_ioctl.h +++ b/include/uapi/linux/kfd_ioctl.h @@ -30,9 +30,10 @@ * - 1.1 - initial version * - 1.3 - Add SMI events support * - 1.4 - Indicate new SRAM EDC bit in device properties + * - 1.5 - Add SVM API */ #define KFD_IOCTL_MAJOR_VERSION 1 -#define KFD_IOCTL_MINOR_VERSION 4 +#define KFD_IOCTL_MINOR_VERSION 5 struct kfd_ioctl_get_version_args { __u32 major_version; /* from KFD */ @@ -473,6 +474,129 @@ enum kfd_mmio_remap { KFD_MMIO_REMAP_HDP_REG_FLUSH_CNTL = 4, }; +/* Guarantee host access to memory */ +#define KFD_IOCTL_SVM_FLAG_HOST_ACCESS 0x00000001 +/* Fine grained coherency between all devices with access */ +#define KFD_IOCTL_SVM_FLAG_COHERENT 0x00000002 +/* Use any GPU in same hive as preferred device */ +#define KFD_IOCTL_SVM_FLAG_HIVE_LOCAL 0x00000004 +/* GPUs only read, allows replication */ +#define KFD_IOCTL_SVM_FLAG_GPU_RO 0x00000008 +/* Allow execution on GPU */ +#define KFD_IOCTL_SVM_FLAG_GPU_EXEC 0x00000010 +/* GPUs mostly read, may allow similar optimizations as RO, but writes fault */ +#define KFD_IOCTL_SVM_FLAG_GPU_READ_MOSTLY 0x00000020 + +/** + * kfd_ioctl_svm_op - SVM ioctl operations + * + * @KFD_IOCTL_SVM_OP_SET_ATTR: Modify one or more attributes + * @KFD_IOCTL_SVM_OP_GET_ATTR: Query one or more attributes + */ +enum kfd_ioctl_svm_op { + KFD_IOCTL_SVM_OP_SET_ATTR, + KFD_IOCTL_SVM_OP_GET_ATTR +}; + +/** kfd_ioctl_svm_location - Enum for preferred and prefetch locations + * + * GPU IDs are used to specify GPUs as preferred and prefetch locations. + * Below definitions are used for system memory or for leaving the preferred + * location unspecified. + */ +enum kfd_ioctl_svm_location { + KFD_IOCTL_SVM_LOCATION_SYSMEM = 0, + KFD_IOCTL_SVM_LOCATION_UNDEFINED = 0xffffffff +}; + +/** + * kfd_ioctl_svm_attr_type - SVM attribute types + * + * @KFD_IOCTL_SVM_ATTR_PREFERRED_LOC: gpuid of the preferred location, 0 for + * system memory + * @KFD_IOCTL_SVM_ATTR_PREFETCH_LOC: gpuid of the prefetch location, 0 for + * system memory. Setting this triggers an + * immediate prefetch (migration). + * @KFD_IOCTL_SVM_ATTR_ACCESS: + * @KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE: + * @KFD_IOCTL_SVM_ATTR_NO_ACCESS: specify memory access for the gpuid given + * by the attribute value + * @KFD_IOCTL_SVM_ATTR_SET_FLAGS: bitmask of flags to set (see + * KFD_IOCTL_SVM_FLAG_...) + * @KFD_IOCTL_SVM_ATTR_CLR_FLAGS: bitmask of flags to clear + * @KFD_IOCTL_SVM_ATTR_GRANULARITY: migration granularity + * (log2 num pages) + */ +enum kfd_ioctl_svm_attr_type { + KFD_IOCTL_SVM_ATTR_PREFERRED_LOC, + KFD_IOCTL_SVM_ATTR_PREFETCH_LOC, + KFD_IOCTL_SVM_ATTR_ACCESS, + KFD_IOCTL_SVM_ATTR_ACCESS_IN_PLACE, + KFD_IOCTL_SVM_ATTR_NO_ACCESS, + KFD_IOCTL_SVM_ATTR_SET_FLAGS, + KFD_IOCTL_SVM_ATTR_CLR_FLAGS, + KFD_IOCTL_SVM_ATTR_GRANULARITY +}; + +/** + * kfd_ioctl_svm_attribute - Attributes as pairs of type and value + * + * The meaning of the @value depends on the attribute type. + * + * @type: attribute type (see enum @kfd_ioctl_svm_attr_type) + * @value: attribute value + */ +struct kfd_ioctl_svm_attribute { + __u32 type; + __u32 value; +}; + +/** + * kfd_ioctl_svm_args - Arguments for SVM ioctl + * + * @op specifies the operation to perform (see enum + * @kfd_ioctl_svm_op). @start_addr and @size are common for all + * operations. + * + * A variable number of attributes can be given in @attrs. + * @nattr specifies the number of attributes. New attributes can be + * added in the future without breaking the ABI. If unknown attributes + * are given, the function returns -EINVAL. + * + * @KFD_IOCTL_SVM_OP_SET_ATTR sets attributes for a virtual address + * range. It may overlap existing virtual address ranges. If it does, + * the existing ranges will be split such that the attribute changes + * only apply to the specified address range. + * + * @KFD_IOCTL_SVM_OP_GET_ATTR returns the intersection of attributes + * over all memory in the given range and returns the result as the + * attribute value. If different pages have different preferred or + * prefetch locations, 0xffffffff will be returned for + * @KFD_IOCTL_SVM_ATTR_PREFERRED_LOC or + * @KFD_IOCTL_SVM_ATTR_PREFETCH_LOC resepctively. For + * @KFD_IOCTL_SVM_ATTR_SET_FLAGS, flags of all pages will be + * aggregated by bitwise AND. The minimum migration granularity + * throughout the range will be returned for + * @KFD_IOCTL_SVM_ATTR_GRANULARITY. + * + * Querying of accessibility attributes works by initializing the + * attribute type to @KFD_IOCTL_SVM_ATTR_ACCESS and the value to the + * GPUID being queried. Multiple attributes can be given to allow + * querying multiple GPUIDs. The ioctl function overwrites the + * attribute type to indicate the access for the specified GPU. + * + * @KFD_IOCTL_SVM_ATTR_CLR_FLAGS is invalid for + * @KFD_IOCTL_SVM_OP_GET_ATTR. + */ +struct kfd_ioctl_svm_args { + __u64 start_addr; + __u64 size; + __u32 op; + __u32 nattr; + /* Variable length array of attributes */ + struct kfd_ioctl_svm_attribute attrs[0]; +}; + #define AMDKFD_IOCTL_BASE 'K' #define AMDKFD_IO(nr) _IO(AMDKFD_IOCTL_BASE, nr) #define AMDKFD_IOR(nr, type) _IOR(AMDKFD_IOCTL_BASE, nr, type) @@ -573,7 +697,9 @@ enum kfd_mmio_remap { #define AMDKFD_IOC_SMI_EVENTS \ AMDKFD_IOWR(0x1F, struct kfd_ioctl_smi_events_args) +#define AMDKFD_IOC_SVM AMDKFD_IOWR(0x20, struct kfd_ioctl_svm_args) + #define AMDKFD_COMMAND_START 0x01 -#define AMDKFD_COMMAND_END 0x20 +#define AMDKFD_COMMAND_END 0x21 #endif -- cgit From 0f7b5c44d4c53710993e4773bd6eaf171f1888e6 Mon Sep 17 00:00:00 2001 From: Alex Sierra Date: Thu, 28 May 2020 18:27:05 -0500 Subject: drm/amdkfd: add ioctl to configure and query xnack retries Xnack retries are used for page fault recovery. Some AMD chip families support continuously retry while page table entries are invalid. The driver must handle the page fault interrupt and fill in a valid entry for the GPU to continue. This ioctl allows to enable/disable XNACK retries per KFD process. Signed-off-by: Alex Sierra Reviewed-by: Felix Kuehling Signed-off-by: Felix Kuehling Signed-off-by: Alex Deucher --- include/uapi/linux/kfd_ioctl.h | 43 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 42 insertions(+), 1 deletion(-) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/kfd_ioctl.h b/include/uapi/linux/kfd_ioctl.h index 247b57baa94f..3cb5b5dd9f77 100644 --- a/include/uapi/linux/kfd_ioctl.h +++ b/include/uapi/linux/kfd_ioctl.h @@ -597,6 +597,44 @@ struct kfd_ioctl_svm_args { struct kfd_ioctl_svm_attribute attrs[0]; }; +/** + * kfd_ioctl_set_xnack_mode_args - Arguments for set_xnack_mode + * + * @xnack_enabled: [in/out] Whether to enable XNACK mode for this process + * + * @xnack_enabled indicates whether recoverable page faults should be + * enabled for the current process. 0 means disabled, positive means + * enabled, negative means leave unchanged. If enabled, virtual address + * translations on GFXv9 and later AMD GPUs can return XNACK and retry + * the access until a valid PTE is available. This is used to implement + * device page faults. + * + * On output, @xnack_enabled returns the (new) current mode (0 or + * positive). Therefore, a negative input value can be used to query + * the current mode without changing it. + * + * The XNACK mode fundamentally changes the way SVM managed memory works + * in the driver, with subtle effects on application performance and + * functionality. + * + * Enabling XNACK mode requires shader programs to be compiled + * differently. Furthermore, not all GPUs support changing the mode + * per-process. Therefore changing the mode is only allowed while no + * user mode queues exist in the process. This ensure that no shader + * code is running that may be compiled for the wrong mode. And GPUs + * that cannot change to the requested mode will prevent the XNACK + * mode from occurring. All GPUs used by the process must be in the + * same XNACK mode. + * + * GFXv8 or older GPUs do not support 48 bit virtual addresses or SVM. + * Therefore those GPUs are not considered for the XNACK mode switch. + * + * Return: 0 on success, -errno on failure + */ +struct kfd_ioctl_set_xnack_mode_args { + __s32 xnack_enabled; +}; + #define AMDKFD_IOCTL_BASE 'K' #define AMDKFD_IO(nr) _IO(AMDKFD_IOCTL_BASE, nr) #define AMDKFD_IOR(nr, type) _IOR(AMDKFD_IOCTL_BASE, nr, type) @@ -699,7 +737,10 @@ struct kfd_ioctl_svm_args { #define AMDKFD_IOC_SVM AMDKFD_IOWR(0x20, struct kfd_ioctl_svm_args) +#define AMDKFD_IOC_SET_XNACK_MODE \ + AMDKFD_IOWR(0x21, struct kfd_ioctl_set_xnack_mode_args) + #define AMDKFD_COMMAND_START 0x01 -#define AMDKFD_COMMAND_END 0x21 +#define AMDKFD_COMMAND_END 0x22 #endif -- cgit