lkml.org 
[lkml]   [2009]   [Feb]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] new irq tracer
On Wed, Feb 25, 2009 at 11:48:28AM -0500, Masami Hiramatsu wrote:
> KOSAKI Motohiro wrote:
> >> /**
> >> * handle_IRQ_event - irq action chain handler
> >> * @irq: the interrupt number
> >> @@ -354,7 +358,9 @@ irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action)
> >> local_irq_enable_in_hardirq();
> >>
> >> do {
> >> + trace_irq_entry(irq);
> >> ret = action->handler(irq, action->dev_id);
> >> + trace_irq_exit(irq, ret);
> >> if (ret == IRQ_HANDLED)
> >> status |= action->flags;
> >> retval |= ret;
> >
> > Nobdy want unnecessary redundant tracepoint.
> > Please discuss with mathieu, and merge his tracepoint.
>
> Hmm, from the viewpoint of trouble shooting, the place of LTTng's tracepoint
> is enough. However, from the same viewpoint, it should pass irq-number
> to irq-exit event too, because we may lost some previous events by buffer-overflow
> etc.
>
> trace_irq_entry(irq, NULL);
> ret = _handle_IRQ_event(irq, action);
> trace_irq_exit(irq, ret);
> ^^^^
>

the lttng tracepoints wrap the calls to _handle_IRQ_event in 3
different places. So the above suggested irq tracepoint provides the
same information with 4 less tracepoints in the code. So I believe its
simpler - plus we can understand which action handlers are handling the
interrupt.

thanks,

-Jason


\
 
 \ /
  Last update: 2009-02-25 18:01    [W:0.117 / U:0.088 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site