diff options
Diffstat (limited to 'include/uapi/linux/kfd_ioctl.h')
| -rw-r--r-- | include/uapi/linux/kfd_ioctl.h | 43 |
1 files changed, 42 insertions, 1 deletions
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 |