centos man page for trace_puts

TRACE_PUTS(9)							   Driver Basics						     TRACE_PUTS(9)

NAME
       trace_puts - write a string into the ftrace buffer

SYNOPSIS
       trace_puts(str);

ARGUMENTS
       str
	   the string to record

NOTE
       __trace_bputs is an internal function for trace_puts and the ip is passed in via the trace_puts macro.

       This is similar to trace_printk but is made for those really fast paths that a developer wants the least amount of "Heisenbug" affects,
       where the processing of the print format is still too much.

       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_puts scattered around in your code. (Extra
       memory is used for special buffers that are allocated when trace_puts is used)

RETURNS
       0 if nothing was written, positive # if string was. (1 when __trace_bputs is used, strlen(str) when __trace_puts is used)

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014							     TRACE_PUTS(9)