suse man page for trace_printk

TRACE_PRINTK(9) 						   Driver Basics						   TRACE_PRINTK(9)

NAME
       trace_printk - printf formatting in the ftrace buffer

SYNOPSIS
       trace_printk(fmt, args...);

ARGUMENTS
       fmt
	   the printf format for printing

       args...
	   variable arguments

NOTE
       __trace_printk is an internal function for trace_printk and the ip is passed in via the trace_printk macro.

       This function allows a kernel developer to debug fast path sections that printk is not appropriate for. By scattering in various printk
       like tracing in the code, a developer can quickly see where problems are occurring.

       This is intended as a debugging tool for the developer only. Please refrain from leaving trace_printks scattered around in your code.

COPYRIGHT
Kernel Hackers Manual 2.6.					     July 2010							   TRACE_PRINTK(9)