Re: [PATCH 1/6] usb: xhci: add xhci_log_cmd trace events

[Lu Baolu]

Hi,

On 02/15/2017 03:58 PM, Felipe Balbi wrote:
> Hi,
>
> Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> writes:
>> diff --git a/drivers/usb/host/xhci-trace.h b/drivers/usb/host/xhci-trace.h
>> index 1ac2cdf..c31eeaf 100644
>> --- a/drivers/usb/host/xhci-trace.h
>> +++ b/drivers/usb/host/xhci-trace.h
>> @@ -285,6 +285,96 @@ DEFINE_EVENT(xhci_log_urb, xhci_urb_dequeue,
>>  	TP_ARGS(urb)
>>  );
>>  
>> +DECLARE_EVENT_CLASS(xhci_log_cmd,
>> +	TP_PROTO(struct xhci_command *cmd),
>> +	TP_ARGS(cmd),
>> +	TP_STRUCT__entry(
>> +		__field(struct xhci_command *, cmd)
>> +		__field(struct xhci_container_ctx *, in_ctx)
>> +		__field(union xhci_trb *, cmd_trb)
>> +		__field(int, slot_id)
>> +		__field(int, status)
>> +		__field(int, type)
>> +	),
>> +	TP_fast_assign(
>> +		__entry->cmd = cmd;
>> +		__entry->in_ctx = cmd->in_ctx;
>> +		__entry->cmd_trb = cmd->command_trb;
>> +		__entry->slot_id = cmd->slot_id;
>> +		__entry->status = cmd->status;
>> +		__entry->type = TRB_FIELD_TO_TYPE(le32_to_cpu(cmd->command_trb->generic.field[3]))
>> +	),
>> +	TP_printk("cmd @%p: %s: in_ctx=@%p, slot_id=%d, cmd_trb=@%p, status=%d",
>> +		__entry->cmd, xhci_trb_type_string(__entry->type),
>> +		__entry->in_ctx, __entry->slot_id, __entry->cmd_trb,
>> +		__entry->status
>> +	)
>> +);
> we already have a generic TRB tracer that decodes every single TRB. What
> is this bringing that the previous doesn't provide?

This tracer traces the life cycle of a command. It gives,

1) Which function started an xhci command?
2) What was name of that command?
3) Did hardware respond to it, or timed out?
4) If hardware responded, what was the execution result?
5) If timed out, did 'abort command ring operation' abort it successfully?
6) Was the command structure freed at last?

> BTW, I also have
> ready Slot and EP context tracers, I didn't send before because I
> already had quite a large series pending for Mathias :-p
>

Sorry for the duplication.

Best regards,
Lu Baolu