tracing: Avoid calling cc-option -mrecord-mcount for every Makefile
Currently if CONFIG_FTRACE_MCOUNT_RECORD is enabled -mrecord-mcount
compiler flag support is tested for every Makefile.
Top 4 cc-option usages:
511 -mrecord-mcount
11 -fno-stack-protector
9 -Wno-override-init
2 -fsched-pressure
To address that move cc-option from scripts/Makefile.build to top Makefile
and export CC_USING_RECORD_MCOUNT to be used in original place.
While doing that also add -mrecord-mcount to CC_FLAGS_FTRACE (if gcc
actually supports it).
Link: http://lkml.kernel.org/r/patch-2.thread-aa7b8d.git-de935bace15a.your-ad-here.call-01533557518-ext-9465@work.hours
Acked-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
diff --git a/Makefile b/Makefile
index 489de42..2c92ebf 100644
--- a/Makefile
+++ b/Makefile
@@ -743,6 +743,13 @@
ifndef CC_FLAGS_FTRACE
CC_FLAGS_FTRACE := -pg
endif
+ifdef CONFIG_FTRACE_MCOUNT_RECORD
+ # gcc 5 supports generating the mcount tables directly
+ ifeq ($(call cc-option-yn,-mrecord-mcount),y)
+ CC_FLAGS_FTRACE += -mrecord-mcount
+ export CC_USING_RECORD_MCOUNT := 1
+ endif
+endif
ifdef CONFIG_HAVE_FENTRY
ifeq ($(call cc-option-yn, -mfentry),y)
CC_FLAGS_FTRACE += -mfentry