Merge tag 'defconfig-for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/arm...

[mirror_ubuntu-artful-kernel.git] / Documentation / trace / ftrace-design.txt

diff --git a/Documentation/trace/ftrace-design.txt b/Documentation/trace/ftrace-design.txt
index 3f669b9e88526e4d9958219876565830c9c0e844..dd5f916b351d1cdd7f11162cb497530973c53940 100644 (file)
--- a/Documentation/trace/ftrace-design.txt
+++ b/Documentation/trace/ftrace-design.txt
@@ -102,30 +102,6 @@ extern void mcount(void);
 EXPORT_SYMBOL(mcount);
 
 
-HAVE_FUNCTION_TRACE_MCOUNT_TEST
--------------------------------
-
-This is an optional optimization for the normal case when tracing is turned off
-in the system.  If you do not enable this Kconfig option, the common ftrace
-code will take care of doing the checking for you.
-
-To support this feature, you only need to check the function_trace_stop
-variable in the mcount function.  If it is non-zero, there is no tracing to be
-done at all, so you can return.
-
-This additional pseudo code would simply be:
-void mcount(void)
-{
-       /* save any bare state needed in order to do initial checking */
-
-+      if (function_trace_stop)
-+              return;
-
-       extern void (*ftrace_trace_function)(unsigned long, unsigned long);
-       if (ftrace_trace_function != ftrace_stub)
-...
-
-
 HAVE_FUNCTION_GRAPH_TRACER
 --------------------------
 
@@ -328,8 +304,6 @@ void mcount(void)
 
 void ftrace_caller(void)
 {
-       /* implement HAVE_FUNCTION_TRACE_MCOUNT_TEST if you desire */
-
        /* save all state needed by the ABI (see paragraph above) */
 
        unsigned long frompc = ...;