Re: [PATCH 13/83] hsa/radeon: Add 2 new IOCTL to kfd, CREATE_QUEUE and DESTROY_QUEUE

[Jerome Glisse <j.glisse@gmail.com>]

On Fri, Jul 11, 2014 at 12:50:13AM +0300, Oded Gabbay wrote:
> This patch adds 2 new IOCTL to kfd driver.
> 
> The first IOCTL is KFD_IOC_CREATE_QUEUE that is used by the user-mode
> application to create a compute queue on the GPU.
> 
> The second IOCTL is KFD_IOC_DESTROY_QUEUE that is used by the
> user-mode application to destroy an existing compute queue on the GPU.
> 
> Signed-off-by: Oded Gabbay <oded.gabbay@amd.com>
> ---
>  drivers/gpu/hsa/radeon/kfd_chardev.c  | 155 ++++++++++++++++++++++++++++++++++
>  drivers/gpu/hsa/radeon/kfd_doorbell.c |  11 +++
>  include/uapi/linux/kfd_ioctl.h        |  69 +++++++++++++++
>  3 files changed, 235 insertions(+)
>  create mode 100644 include/uapi/linux/kfd_ioctl.h
> 
> diff --git a/drivers/gpu/hsa/radeon/kfd_chardev.c b/drivers/gpu/hsa/radeon/kfd_chardev.c
> index 0b5bc74..4e7d5d0 100644
> --- a/drivers/gpu/hsa/radeon/kfd_chardev.c
> +++ b/drivers/gpu/hsa/radeon/kfd_chardev.c
> @@ -27,11 +27,13 @@
>  #include <linux/sched.h>
>  #include <linux/slab.h>
>  #include <linux/uaccess.h>
> +#include <uapi/linux/kfd_ioctl.h>
>  #include "kfd_priv.h"
>  #include "kfd_scheduler.h"
>  
>  static long kfd_ioctl(struct file *, unsigned int, unsigned long);
>  static int kfd_open(struct inode *, struct file *);
> +static int kfd_mmap(struct file *, struct vm_area_struct *);
>  
>  static const char kfd_dev_name[] = "kfd";
>  
> @@ -108,17 +110,170 @@ kfd_open(struct inode *inode, struct file *filep)
>  	return 0;
>  }
>  
> +static long
> +kfd_ioctl_create_queue(struct file *filep, struct kfd_process *p, void __user *arg)
> +{
> +	struct kfd_ioctl_create_queue_args args;
> +	struct kfd_dev *dev;
> +	int err = 0;
> +	unsigned int queue_id;
> +	struct kfd_queue *queue;
> +	struct kfd_process_device *pdd;
> +
> +	if (copy_from_user(&args, arg, sizeof(args)))
> +		return -EFAULT;
> +
> +	dev = radeon_kfd_device_by_id(args.gpu_id);
> +	if (dev == NULL)
> +		return -EINVAL;
> +
> +	queue = kzalloc(
> +		offsetof(struct kfd_queue, scheduler_queue) + dev->device_info->scheduler_class->queue_size,
> +		GFP_KERNEL);
> +
> +	if (!queue)
> +		return -ENOMEM;
> +
> +	queue->dev = dev;
> +
> +	mutex_lock(&p->mutex);
> +
> +	pdd = radeon_kfd_bind_process_to_device(dev, p);
> +	if (IS_ERR(pdd) < 0) {
> +		err = PTR_ERR(pdd);
> +		goto err_bind_pasid;
> +	}
> +
> +	pr_debug("kfd: creating queue number %d for PASID %d on GPU 0x%x\n",
> +			pdd->queue_count,
> +			p->pasid,
> +			dev->id);
> +
> +	if (pdd->queue_count++ == 0) {
> +		err = dev->device_info->scheduler_class->register_process(dev->scheduler, p, &pdd->scheduler_process);
> +		if (err < 0)
> +			goto err_register_process;
> +	}
> +
> +	if (!radeon_kfd_allocate_queue_id(p, &queue_id))
> +		goto err_allocate_queue_id;
> +
> +	err = dev->device_info->scheduler_class->create_queue(dev->scheduler, pdd->scheduler_process,
> +							      &queue->scheduler_queue,
> +							      (void __user *)args.ring_base_address,
> +							      args.ring_size,
> +							      (void __user *)args.read_pointer_address,
> +							      (void __user *)args.write_pointer_address,
> +							      radeon_kfd_queue_id_to_doorbell(dev, p, queue_id));
> +	if (err)
> +		goto err_create_queue;
> +
> +	radeon_kfd_install_queue(p, queue_id, queue);
> +
> +	args.queue_id = queue_id;
> +	args.doorbell_address = (uint64_t)(uintptr_t)radeon_kfd_get_doorbell(filep, p, dev, queue_id);
> +
> +	if (copy_to_user(arg, &args, sizeof(args))) {
> +		err = -EFAULT;
> +		goto err_copy_args_out;
> +	}
> +
> +	mutex_unlock(&p->mutex);
> +
> +	pr_debug("kfd: queue id %d was created successfully.\n"
> +		 "     ring buffer address == 0x%016llX\n"
> +		 "     read ptr address    == 0x%016llX\n"
> +		 "     write ptr address   == 0x%016llX\n"
> +		 "     doorbell address    == 0x%016llX\n",
> +			args.queue_id,
> +			args.ring_base_address,
> +			args.read_pointer_address,
> +			args.write_pointer_address,
> +			args.doorbell_address);
> +
> +	return 0;
> +
> +err_copy_args_out:
> +	dev->device_info->scheduler_class->destroy_queue(dev->scheduler, &queue->scheduler_queue);
> +err_create_queue:
> +	radeon_kfd_remove_queue(p, queue_id);
> +err_allocate_queue_id:
> +	if (--pdd->queue_count == 0) {
> +		dev->device_info->scheduler_class->deregister_process(dev->scheduler, pdd->scheduler_process);
> +		pdd->scheduler_process = NULL;
> +	}
> +err_register_process:
> +err_bind_pasid:
> +	kfree(queue);
> +	mutex_unlock(&p->mutex);
> +	return err;
> +}
> +
> +static int
> +kfd_ioctl_destroy_queue(struct file *filp, struct kfd_process *p, void __user *arg)
> +{
> +	struct kfd_ioctl_destroy_queue_args args;
> +	struct kfd_queue *queue;
> +	struct kfd_dev *dev;
> +	struct kfd_process_device *pdd;
> +
> +	if (copy_from_user(&args, arg, sizeof(args)))
> +		return -EFAULT;
> +
> +	mutex_lock(&p->mutex);
> +
> +	queue = radeon_kfd_get_queue(p, args.queue_id);
> +	if (!queue) {
> +		mutex_unlock(&p->mutex);
> +		return -EINVAL;
> +	}
> +
> +	dev = queue->dev;
> +
> +	pr_debug("kfd: destroying queue id %d for PASID %d\n",
> +			args.queue_id,
> +			p->pasid);
> +
> +	radeon_kfd_remove_queue(p, args.queue_id);
> +	dev->device_info->scheduler_class->destroy_queue(dev->scheduler, &queue->scheduler_queue);
> +
> +	kfree(queue);
> +
> +	pdd = radeon_kfd_get_process_device_data(dev, p);
> +	BUG_ON(pdd == NULL); /* Because a queue exists. */
> +
> +	if (--pdd->queue_count == 0) {
> +		dev->device_info->scheduler_class->deregister_process(dev->scheduler, pdd->scheduler_process);
> +		pdd->scheduler_process = NULL;
> +	}
> +
> +	mutex_unlock(&p->mutex);
> +	return 0;
> +}
>  
>  static long
>  kfd_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
>  {
> +	struct kfd_process *process;
>  	long err = -EINVAL;
>  
>  	dev_info(kfd_device,
>  		 "ioctl cmd 0x%x (#%d), arg 0x%lx\n",
>  		 cmd, _IOC_NR(cmd), arg);
>  
> +	process = radeon_kfd_get_process(current);
> +	if (IS_ERR(process))
> +		return PTR_ERR(process);
> +
>  	switch (cmd) {
> +	case KFD_IOC_CREATE_QUEUE:
> +		err = kfd_ioctl_create_queue(filep, process, (void __user *)arg);
> +		break;
> +
> +	case KFD_IOC_DESTROY_QUEUE:
> +		err = kfd_ioctl_destroy_queue(filep, process, (void __user *)arg);
> +		break;
> +
>  	default:
>  		dev_err(kfd_device,
>  			"unknown ioctl cmd 0x%x, arg 0x%lx)\n",
> diff --git a/drivers/gpu/hsa/radeon/kfd_doorbell.c b/drivers/gpu/hsa/radeon/kfd_doorbell.c
> index e1d8506..3de8a02 100644
> --- a/drivers/gpu/hsa/radeon/kfd_doorbell.c
> +++ b/drivers/gpu/hsa/radeon/kfd_doorbell.c
> @@ -155,3 +155,14 @@ doorbell_t __user *radeon_kfd_get_doorbell(struct file *devkfd, struct kfd_proce
>  	return &pdd->doorbell_mapping[doorbell_index];
>  }
>  
> +/*
> + * queue_ids are in the range [0,MAX_PROCESS_QUEUES) and are mapped 1:1
> + * to doorbells with the process's doorbell page
> + */
> +unsigned int radeon_kfd_queue_id_to_doorbell(struct kfd_dev *kfd, struct kfd_process *process, unsigned int queue_id)
> +{
> +	/* doorbell_id_offset accounts for doorbells taken by KGD.
> +	 * pasid * doorbell_process_allocation/sizeof(doorbell_t) adjusts to the process's doorbells */
> +	return kfd->doorbell_id_offset + process->pasid * (doorbell_process_allocation()/sizeof(doorbell_t)) + queue_id;
> +}
> +
> diff --git a/include/uapi/linux/kfd_ioctl.h b/include/uapi/linux/kfd_ioctl.h
> new file mode 100644
> index 0000000..dcc5fe0
> --- /dev/null
> +++ b/include/uapi/linux/kfd_ioctl.h
> @@ -0,0 +1,69 @@
> +/*
> + * Copyright 2014 Advanced Micro Devices, Inc.
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the "Software"),
> + * to deal in the Software without restriction, including without limitation
> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
> + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
> + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
> + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
> + * OTHER DEALINGS IN THE SOFTWARE.
> + */
> +
> +#ifndef KFD_IOCTL_H_INCLUDED
> +#define KFD_IOCTL_H_INCLUDED
> +
> +#include <linux/types.h>
> +#include <linux/ioctl.h>
> +
> +#define KFD_IOCTL_CURRENT_VERSION 1
> +
> +/* The 64-bit ABI is the authoritative version. */
> +#pragma pack(push, 8)
> +
> +struct kfd_ioctl_get_version_args {
> +	uint32_t min_supported_version;	/* from KFD */
> +	uint32_t max_supported_version;	/* from KFD */
> +};
> +
> +/* For kfd_ioctl_create_queue_args.queue_type. */
> +#define KFD_IOC_QUEUE_TYPE_COMPUTE   0
> +#define KFD_IOC_QUEUE_TYPE_SDMA      1
> +
> +struct kfd_ioctl_create_queue_args {
> +	uint64_t ring_base_address;	/* to KFD */
> +	uint32_t ring_size;		/* to KFD */
> +	uint32_t gpu_id;		/* to KFD */
> +	uint32_t queue_type;		/* to KFD */
> +	uint32_t queue_percentage;	/* to KFD */
> +	uint32_t queue_priority;	/* to KFD */

Is this priority global accross all process or local to the process ?
Local is fine. But global is not, if you want some global priority
best is probably to go use some value provided by cgroup.

> +	uint64_t write_pointer_address;	/* to KFD */
> +	uint64_t read_pointer_address;	/* to KFD */
> +
> +	uint64_t doorbell_address;	/* from KFD */
> +	uint32_t queue_id;		/* from KFD */
> +};
> +
> +struct kfd_ioctl_destroy_queue_args {
> +	uint32_t queue_id;		/* to KFD */
> +};
> +
> +#define KFD_IOC_MAGIC 'K'
> +
> +#define KFD_IOC_GET_VERSION	_IOR(KFD_IOC_MAGIC, 1, struct kfd_ioctl_get_version_args)
> +#define KFD_IOC_CREATE_QUEUE	_IOWR(KFD_IOC_MAGIC, 2, struct kfd_ioctl_create_queue_args)
> +#define KFD_IOC_DESTROY_QUEUE	_IOWR(KFD_IOC_MAGIC, 3, struct kfd_ioctl_destroy_queue_args)
> +
> +#pragma pack(pop)
> +
> +#endif
> -- 
> 1.9.1
>