tracing: avoid build warning with HAVE_NOP_MCOUNT

Selecting HAVE_NOP_MCOUNT enables -mnop-mcount (if gcc supports it)
and sets CC_USING_NOP_MCOUNT. Reuse __is_defined (which is suitable for
testing CC_USING_* defines) to avoid conditional compilation and fix
the following gcc 9 warning on s390:

kernel/trace/ftrace.c:2514:1: warning: ‘ftrace_code_disable’ defined
but not used [-Wunused-function]

Link: http://lkml.kernel.org/r/patch.git-1a82d13f33ac.your-ad-here.call-01559732716-ext-6629@work.hours

Fixes: 2f4df0017b ("tracing: Add -mcount-nop option support")
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Vasily Gorbik 2019-06-05 13:11:58 +02:00 committed by Steven Rostedt (VMware)
parent becf33f694
commit cbdaeaf050

View File

@ -2935,14 +2935,13 @@ static int ftrace_update_code(struct module *mod, struct ftrace_page *new_pgs)
p = &pg->records[i];
p->flags = rec_flags;
#ifndef CC_USING_NOP_MCOUNT
/*
* Do the initial record conversion from mcount jump
* to the NOP instructions.
*/
if (!ftrace_code_disable(mod, p))
if (!__is_defined(CC_USING_NOP_MCOUNT) &&
!ftrace_code_disable(mod, p))
break;
#endif
update_cnt++;
}