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authorSteven Rostedt (Red Hat) <rostedt@goodmis.org>2014-06-25 13:26:59 -0400
committerSteven Rostedt <rostedt@goodmis.org>2014-07-18 13:57:01 -0400
commit7544256aa20356e506b0d179f9b6abc661847e2f (patch)
treeb626f07aff5928a44c1304f2f6e6f99e9a10a9c5 /Documentation/trace/ftrace-design.txt
parent1d48d5960f9f24b8afd5b1dbb10bfe17b5f29a35 (diff)
downloadop-kernel-dev-7544256aa20356e506b0d179f9b6abc661847e2f.zip
op-kernel-dev-7544256aa20356e506b0d179f9b6abc661847e2f.tar.gz
ftrace: Remove check for HAVE_FUNCTION_TRACE_MCOUNT_TEST
function_trace_stop is no longer used to disable function tracing. This means that archs are no longer limited if it does not support checking this variable in the mcount trampoline. No need to use the list_func for archs that do not support this obsolete method. Acked-by: James Hogan <james.hogan@imgtec.com> Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'Documentation/trace/ftrace-design.txt')
-rw-r--r--Documentation/trace/ftrace-design.txt26
1 files changed, 0 insertions, 26 deletions
diff --git a/Documentation/trace/ftrace-design.txt b/Documentation/trace/ftrace-design.txt
index 3f669b9..dd5f916 100644
--- 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 = ...;
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