3.2.101-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Frantisek Hrbata <fhrb...@redhat.com>
commit 17c568d60af5a810208baf116dc174a2005c6c3e upstream.
Compile the correct gcov implementation file for the specific gcc version.
Signed-off-by: Frantisek Hrbata <fhrb...@redhat.com>
Cc: Jan Stancek <jstan...@redhat.com>
Cc: Kees Cook <keesc...@chromium.org>
Acked-by: Peter Oberparleiter <peter.oberparlei...@de.ibm.com>
Cc: Rusty Russell <ru...@rustcorp.com.au>
Cc: Arnd Bergmann <a...@arndb.de>
Cc: Andy Gospodarek <agosp...@redhat.com>
Signed-off-by: Andrew Morton <a...@linux-foundation.org>
Signed-off-by: Linus Torvalds <torva...@linux-foundation.org>
Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---
Documentation/gcov.txt | 4 ++++
kernel/gcov/Kconfig | 30 ++++++++++++++++++++++++++++++
kernel/gcov/Makefile | 32 +++++++++++++++++++++++++++++++-
3 files changed, 65 insertions(+), 1 deletion(-)
--- a/Documentation/gcov.txt
+++ b/Documentation/gcov.txt
@@ -50,6 +50,10 @@ Configure the kernel with:
CONFIG_DEBUG_FS=y
CONFIG_GCOV_KERNEL=y
+select the gcc's gcov format, default is autodetect based on gcc version:
+
+ CONFIG_GCOV_FORMAT_AUTODETECT=y
+
and to get coverage data for the entire kernel:
CONFIG_GCOV_PROFILE_ALL=y
--- a/kernel/gcov/Kconfig
+++ b/kernel/gcov/Kconfig
@@ -46,4 +46,34 @@ config GCOV_PROFILE_ALL
larger and run slower. Also be sure to exclude files from profiling
which are not linked to the kernel image to prevent linker errors.
+choice
+ prompt "Specify GCOV format"
+ depends on GCOV_KERNEL
+ default GCOV_FORMAT_AUTODETECT
+ ---help---
+ The gcov format is usually determined by the GCC version, but there are
+ exceptions where format changes are integrated in lower-version GCCs.
+ In such a case use this option to adjust the format used in the kernel
+ accordingly.
+
+ If unsure, choose "Autodetect".
+
+config GCOV_FORMAT_AUTODETECT
+ bool "Autodetect"
+ ---help---
+ Select this option to use the format that corresponds to your GCC
+ version.
+
+config GCOV_FORMAT_3_4
+ bool "GCC 3.4 format"
+ ---help---
+ Select this option to use the format defined by GCC 3.4.
+
+config GCOV_FORMAT_4_7
+ bool "GCC 4.7 format"
+ ---help---
+ Select this option to use the format defined by GCC 4.7.
+
+endchoice
+
endmenu
--- a/kernel/gcov/Makefile
+++ b/kernel/gcov/Makefile
@@ -1,3 +1,33 @@
ccflags-y := -DSRCTREE='"$(srctree)"' -DOBJTREE='"$(objtree)"'
-obj-$(CONFIG_GCOV_KERNEL) := base.o fs.o gcc_3_4.o
+# if-lt
+# Usage VAR := $(call if-lt, $(a), $(b))
+# Returns 1 if (a < b)
+if-lt = $(shell [ $(1) -lt $(2) ] && echo 1)
+
+ifeq ($(CONFIG_GCOV_FORMAT_3_4),y)
+ cc-ver := 0304
+else ifeq ($(CONFIG_GCOV_FORMAT_4_7),y)
+ cc-ver := 0407
+else
+# Use cc-version if available, otherwise set 0
+#
+# scripts/Kbuild.include, which contains cc-version function, is not included
+# during make clean "make -f scripts/Makefile.clean obj=kernel/gcov"
+# Meaning cc-ver is empty causing if-lt test to fail with
+# "/bin/sh: line 0: [: -lt: unary operator expected" error mesage.
+# This has no affect on the clean phase, but the error message could be
+# confusing/annoying. So this dummy workaround sets cc-ver to zero if
cc-version
+# is not available. We can probably move if-lt to Kbuild.include, so it's also
+# not defined during clean or to include Kbuild.include in
+# scripts/Makefile.clean. But the following workaround seems least invasive.
+ cc-ver := $(if $(call cc-version),$(call cc-version),0)
+endif
+
+obj-$(CONFIG_GCOV_KERNEL) := base.o fs.o
+
+ifeq ($(call if-lt, $(cc-ver), 0407),1)
+ obj-$(CONFIG_GCOV_KERNEL) += gcc_3_4.o
+else
+ obj-$(CONFIG_GCOV_KERNEL) += gcc_4_7.o
+endif
