Re: [PATCH v2 3/8] drm/amdkfd: Enable per process SMI event

[Felix Kuehling <felix.kuehling@xxxxxxx>]

Am 2022-01-20 um 18:13 schrieb Philip Yang:
> Process receive event from same process by default. Add a flag to be
> able to receive event from all processes, this requires super user
> permission.
>
> Event with pid 0 send to all processes, to keep the default behavior of
> existing SMI events.
>
> Signed-off-by: Philip Yang <Philip.Yang@xxxxxxx>

Reviewed-by: Felix Kuehling <Felix.Kuehling@xxxxxxx>


> ---
>   drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c | 29 ++++++++++++++++-----
>   1 file changed, 22 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c b/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
> index 18ed1b72f0f7..68c93701c5f7 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_smi_events.c
> @@ -37,6 +37,8 @@ struct kfd_smi_client {
>   	uint64_t events;
>   	struct kfd_dev *dev;
>   	spinlock_t lock;
> +	pid_t pid;
> +	bool suser;
>   };
>   
>   #define MAX_KFIFO_SIZE	1024
> @@ -150,16 +152,27 @@ static int kfd_smi_ev_release(struct inode *inode, struct file *filep)
>   	return 0;
>   }
>   
> -static void add_event_to_kfifo(struct kfd_dev *dev, unsigned int smi_event,
> -			      char *event_msg, int len)
> +static bool kfd_smi_ev_enabled(pid_t pid, struct kfd_smi_client *client,
> +			       unsigned int event)
> +{
> +	uint64_t all = KFD_SMI_EVENT_MASK_FROM_INDEX(KFD_SMI_EVENT_ALL_PROCESS);
> +	uint64_t events = READ_ONCE(client->events);
> +
> +	if (pid && client->pid != pid && !(client->suser && (events & all)))
> +		return false;
> +
> +	return events & KFD_SMI_EVENT_MASK_FROM_INDEX(event);
> +}
> +
> +static void add_event_to_kfifo(pid_t pid, struct kfd_dev *dev,
> +			       unsigned int smi_event, char *event_msg, int len)
>   {
>   	struct kfd_smi_client *client;
>   
>   	rcu_read_lock();
>   
>   	list_for_each_entry_rcu(client, &dev->smi_clients, list) {
> -		if (!(READ_ONCE(client->events) &
> -				KFD_SMI_EVENT_MASK_FROM_INDEX(smi_event)))
> +		if (!kfd_smi_ev_enabled(pid, client, smi_event))
>   			continue;
>   		spin_lock(&client->lock);
>   		if (kfifo_avail(&client->fifo) >= len) {
> @@ -202,7 +215,7 @@ void kfd_smi_event_update_gpu_reset(struct kfd_dev *dev, bool post_reset)
>   	len = snprintf(fifo_in, sizeof(fifo_in), "%x %x\n", event,
>   						dev->reset_seq_num);
>   
> -	add_event_to_kfifo(dev, event, fifo_in, len);
> +	add_event_to_kfifo(0, dev, event, fifo_in, len);
>   }
>   
>   void kfd_smi_event_update_thermal_throttling(struct kfd_dev *dev,
> @@ -225,7 +238,7 @@ void kfd_smi_event_update_thermal_throttling(struct kfd_dev *dev,
>   		       KFD_SMI_EVENT_THERMAL_THROTTLE, throttle_bitmask,
>   		       amdgpu_dpm_get_thermal_throttling_counter(dev->adev));
>   
> -	add_event_to_kfifo(dev, KFD_SMI_EVENT_THERMAL_THROTTLE,	fifo_in, len);
> +	add_event_to_kfifo(0, dev, KFD_SMI_EVENT_THERMAL_THROTTLE, fifo_in, len);
>   }
>   
>   void kfd_smi_event_update_vmfault(struct kfd_dev *dev, uint16_t pasid)
> @@ -250,7 +263,7 @@ void kfd_smi_event_update_vmfault(struct kfd_dev *dev, uint16_t pasid)
>   	len = snprintf(fifo_in, sizeof(fifo_in), "%x %x:%s\n", KFD_SMI_EVENT_VMFAULT,
>   		task_info.pid, task_info.task_name);
>   
> -	add_event_to_kfifo(dev, KFD_SMI_EVENT_VMFAULT, fifo_in, len);
> +	add_event_to_kfifo(0, dev, KFD_SMI_EVENT_VMFAULT, fifo_in, len);
>   }
>   
>   int kfd_smi_event_open(struct kfd_dev *dev, uint32_t *fd)
> @@ -282,6 +295,8 @@ int kfd_smi_event_open(struct kfd_dev *dev, uint32_t *fd)
>   	spin_lock_init(&client->lock);
>   	client->events = 0;
>   	client->dev = dev;
> +	client->pid = current->pid;
> +	client->suser = capable(CAP_SYS_ADMIN);
>   
>   	spin_lock(&dev->smi_lock);
>   	list_add_rcu(&client->list, &dev->smi_clients);