gcov: add gcov profiling infrastructure

Index: linux-2.6.26-rc4/Makefile
===================================================================
@@ -320,6 +320,7 @@ AFLAGS_MODULE   = $(MODFLAGS)
 LDFLAGS_MODULE  =
 CFLAGS_KERNEL	=
 AFLAGS_KERNEL	=
+CFLAGS_GCOV	= -fprofile-arcs -ftest-coverage
 
 
 # Use LINUXINCLUDE when you must reference the include/ directory.

@@ -345,7 +346,7 @@ export CPP AR NM STRIP OBJCOPY OBJDUMP M
 export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
 
 export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
-export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE
+export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV
 export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
 
 # When compiling out-of-tree modules, put MODVERDIR in the module

@@ -1133,7 +1134,8 @@ clean: archclean $(clean-dirs)
 	@find . $(RCS_FIND_IGNORE) \
 		\( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
 		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
-		-o -name '*.symtypes' -o -name 'modules.order' \) \
+		-o -name '*.symtypes' -o -name 'modules.order' \
+		-o -name '*.gcno' \) \
 		-type f -print | xargs rm -f
 
 # mrproper - Delete all generated files, including .config

@@ -1337,8 +1339,8 @@ clean: $(clean-dirs)
 	$(call cmd,rmfiles)
 	@find $(KBUILD_EXTMOD) $(RCS_FIND_IGNORE) \
 		\( -name '*.[oas]' -o -name '*.ko' -o -name '.*.cmd' \
-		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \) \
-		-type f -print | xargs rm -f
+		-o -name '.*.d' -o -name '.*.tmp' -o -name '*.mod.c' \
+		-o -name '*.gcno' \) -type f -print | xargs rm -f
 
 help:
 	@echo  '  Building external modules.'

Index: linux-2.6.26-rc4/scripts/Makefile.lib
===================================================================
@@ -100,6 +100,14 @@ _c_flags       = $(KBUILD_CFLAGS) $(ccfl
 _a_flags       = $(KBUILD_AFLAGS) $(asflags-y) $(AFLAGS_$(basetarget).o)
 _cpp_flags     = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F))
 
+# Enable profiling flags for a file, directory or for all files depending on
+# variables GCOV_obj.o, GCOV and CONFIG_GCOV_PROFILE_ALL (in this order)
+ifeq ($(CONFIG_GCOV_PROFILE),y)
+_c_flags += $(if $(patsubst n%,, \
+		$(GCOV_$(basetarget).o)$(GCOV)$(CONFIG_GCOV_PROFILE_ALL)), \
+		$(CFLAGS_GCOV))
+endif
+
 # If building the kernel in a separate objtree expand all occurrences
 # of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/').
 

45 lines not on this page · raw message

Index: linux-2.6.26-rc4/kernel/Makefile
===================================================================
@@ -69,6 +69,7 @@ obj-$(CONFIG_TASK_DELAY_ACCT) += delayac
 obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o
 obj-$(CONFIG_MARKERS) += marker.o
 obj-$(CONFIG_LATENCYTOP) += latencytop.o
+obj-$(CONFIG_GCOV_PROFILE) += gcov/
 
 ifneq ($(CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER),y)
 # According to Alan Modra <[email protected]>, the -fno-omit-frame-pointer is

Index: linux-2.6.26-rc4/kernel/gcov/Makefile
===================================================================
@@ -0,0 +1 @@
+obj-$(CONFIG_GCOV_PROFILE) := base.o fs.o gcc_3_4.o

Index: linux-2.6.26-rc4/Documentation/kernel-parameters.txt
===================================================================
@@ -42,6 +42,7 @@ parameter is applicable:
 	EFI	EFI Partitioning (GPT) is enabled
 	EIDE	EIDE/ATAPI support is enabled.
 	FB	The frame buffer device is enabled.
+	GCOV	GCOV profiling is enabled.
 	HW	Appropriate hardware is enabled.
 	IA-64	IA-64 architecture is enabled.
 	IOSCHED	More than one I/O scheduler is enabled.

@@ -704,6 +705,12 @@ and is between 256 and 4096 characters. 
 			Format: off | on
 			default: on
 
+	gcov_persist=	[GCOV] When non-zero (default), profiling data for
+			kernel modules is saved and remains accessible via
+			debugfs, even when the module is unloaded/reloaded.
+			When zero, profiling data is discarded and associated
+			debugfs files are removed at module unload time.
+
 	gdth=		[HW,SCSI]
 			See header of drivers/scsi/gdth.c.
 

136 lines not on this page · raw message

Index: linux-2.6.26-rc4/arch/Kconfig
===================================================================
@@ -39,3 +39,5 @@ config HAVE_KRETPROBES
 
 config HAVE_DMA_ATTRS
 	def_bool n
+
+source "kernel/gcov/Kconfig"