Re: [patch 08/17] LTTng instrumentation - kernel

[Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>]

* Steven Rostedt (rostedt@goodmis.org) wrote:
> 
> 
> On Tue, 15 Jul 2008, Mathieu Desnoyers wrote:
> >
> >  /*
> >   * Low level drivers may need that to know if they can schedule in
> > @@ -601,6 +603,7 @@ asmlinkage int printk(const char *fmt, .
> >  	int r;
> >
> >  	va_start(args, fmt);
> > +	trace_kernel_printk(__builtin_return_address(0));
> 
> BTW, ftrace.h has macros that let you use CALLER_ADDR0 for
> __builtin_return_address. It also converts it from a pointer to a long,
> but makes the code look prettier.
> 

include/linux/kernel.h:#define _RET_IP_   (unsigned long)__builtin_return_address(0)

Hrm, did not see this one. So I guess we can both switch to it ?

Thanks for pointing this out,

Mathieu

> 
> >  	r = vprintk(fmt, args);
> >  	va_end(args);
> >
> > @@ -677,6 +680,9 @@ asmlinkage int vprintk(const char *fmt,
> >  	raw_local_irq_save(flags);
> >  	this_cpu = smp_processor_id();
> >
> > +	trace_kernel_vprintk(__builtin_return_address(0),
> > +		printk_buf, printed_len);
> > +
> >  	/*
> >  	 * Ouch, printk recursed into itself!
> >  	 */
> 
> -- Steve
> 

-- 
Mathieu Desnoyers
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