Name
trace_irq_handler_entry — 
  called immediately before the irq action handler
 
Synopsis
| void trace_irq_handler_entry ( | int irq, | 
|  | struct irqaction * action ); | 
 
Arguments
- irq
- 
     irq number
     
- action
- 
     pointer to struct irqaction
     
Description
   The struct irqaction pointed to by action contains various
   information about the handler, including the device name,
   action->name, and the device id, action->dev_id. When used in
   conjunction with the irq_handler_exit tracepoint, we can figure
   out irq handler latencies.