drm_xe_exec_queue_create Struct Reference

#include <xe_drm.h>

Public Attributes
__u64	extensions
__u16	width
__u16	num_placements
__u32	vm_id
__u32	flags
__u32	exec_queue_id
__u64	instances
__u64	reserved [2]

Detailed Description

struct drm_xe_exec_queue_create - Input of &DRM_IOCTL_XE_EXEC_QUEUE_CREATE

This ioctl supports setting the following properties via the DRM_XE_EXEC_QUEUE_EXTENSION_SET_PROPERTY extension, which uses the generic &struct drm_xe_ext_set_property:

• DRM_XE_EXEC_QUEUE_SET_PROPERTY_PRIORITY - set the queue priority. CAP_SYS_NICE is required to set a value above normal.
• DRM_XE_EXEC_QUEUE_SET_PROPERTY_TIMESLICE - set the queue timeslice duration in microseconds.
• DRM_XE_EXEC_QUEUE_SET_PROPERTY_PXP_TYPE - set the type of PXP session this queue will be used with. Valid values are listed in enum drm_xe_pxp_session_type. DRM_XE_PXP_TYPE_NONE is the default behavior, so there is no need to explicitly set that. When a queue of type DRM_XE_PXP_TYPE_HWDRM is created, the PXP default HWDRM session (DRM_XE_PXP_HWDRM_DEFAULT_SESSION) will be started, if it isn't already running. The user is expected to query the PXP status via the query ioctl (see DRM_XE_DEVICE_QUERY_PXP_STATUS) and to wait for PXP to be ready before attempting to create a queue with this property. When a queue is created before PXP is ready, the ioctl will return -EBUSY if init is still in progress or -EIO if init failed. Given that going into a power-saving state kills PXP HWDRM sessions, runtime PM will be blocked while queues of this type are alive. All PXP queues will be killed if a PXP invalidation event occurs.
• DRM_XE_EXEC_QUEUE_SET_PROPERTY_MULTI_GROUP - Create a multi-queue group or add secondary queues to a multi-queue group. If the extension's 'value' field has DRM_XE_MULTI_GROUP_CREATE flag set, then a new multi-queue group is created with this queue as the primary queue (Q0). Otherwise, the queue gets added to the multi-queue group whose primary queue's exec_queue_id is specified in the lower 32 bits of the 'value' field. All the other non-relevant bits of extension's 'value' field while adding the primary or the secondary queues of the group must be set to 0.
• DRM_XE_EXEC_QUEUE_SET_PROPERTY_MULTI_QUEUE_PRIORITY - Set the queue priority within the multi-queue group. Current valid priority values are 0–2 (default is 1), with higher values indicating higher priority.
• DRM_XE_EXEC_QUEUE_SET_DISABLE_STATE_CACHE_PERF_FIX - Set the queue to enable render color cache keying on BTP+BTI instead of just BTI (only valid for render queues).

The example below shows how to use &struct drm_xe_exec_queue_create to create a simple exec_queue (no parallel submission) of class DRM_XE_ENGINE_CLASS_RENDER.

.. code-block:: C

struct drm_xe_engine_class_instance instance = {
    .engine_class = DRM_XE_ENGINE_CLASS_RENDER,
};
struct drm_xe_exec_queue_create exec_queue_create = {
     .extensions = 0,
     .vm_id = vm,
     .width = 1,
     .num_placements = 1,
     .instances = to_user_pointer(&instance),
};
ioctl(fd, DRM_IOCTL_XE_EXEC_QUEUE_CREATE, &exec_queue_create);

Allow users to provide a hint to kernel for cases demanding low latency profile. Please note it will have impact on power consumption. User can indicate low latency hint with flag while creating exec queue as mentioned below:

.. code-block:: C

struct drm_xe_exec_queue_create exec_queue_create = {
     .flags = DRM_XE_EXEC_QUEUE_LOW_LATENCY_HINT,
     .extensions = 0,
     .vm_id = vm,
     .width = 1,
     .num_placements = 1,
     .instances = to_user_pointer(&instance),
};
ioctl(fd, DRM_IOCTL_XE_EXEC_QUEUE_CREATE, &exec_queue_create);

Member Data Documentation

exec_queue_id

__u32 drm_xe_exec_queue_create::exec_queue_id

@exec_queue_id: Returned exec queue ID

extensions

__u64 drm_xe_exec_queue_create::extensions

@extensions: Pointer to the first extension struct, if any

flags

__u32 drm_xe_exec_queue_create::flags

@flags: flags to use for this exec queue

instances

__u64 drm_xe_exec_queue_create::instances

@instances: user pointer to a 2-d array of struct drm_xe_engine_class_instance

length = width (i) * num_placements (j) index = j + i * width

num_placements

__u16 drm_xe_exec_queue_create::num_placements

@num_placements: number of valid placements for this exec queue

reserved

__u64 drm_xe_exec_queue_create::reserved[2]

@reserved: Reserved

vm_id

__u32 drm_xe_exec_queue_create::vm_id

@vm_id: VM to use for this exec queue

width

__u16 drm_xe_exec_queue_create::width

@width: submission width (number BB per exec) for this exec queue

---

The documentation for this struct was generated from the following file:

• XenevaOS/BaseHdr/uapi/drm/xe_drm.h