[RFC PATCH V5] GCOV: Add config to check the preqequisites situation

[gengcixi]

From: Cixi Geng <cixi.geng1@xxxxxxxxxx>

Introduce new configuration option GCOV_PROFILE_PREREQS that can be
used to check whether the prerequisites for enabling gcov profiling
for specific files and directories are met.

Only add SERIAL_GCOV for an example.

Signed-off-by: Cixi Geng <cixi.geng1@xxxxxxxxxx>
---
 drivers/tty/serial/Kconfig  |  8 ++++++++
 drivers/tty/serial/Makefile |  1 +
 kernel/gcov/Kconfig         | 15 +++++++++++++++
 3 files changed, 24 insertions(+)

diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index adf9e80e7dc9..3d7e811d90dc 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -1566,3 +1566,11 @@ endmenu
 
 config SERIAL_MCTRL_GPIO
 	tristate
+
+config SERIAL_GCOV
+	bool "Enable profile gcov for serial directory"
+	depends on GCOV_PROFILE_PREREQS
+	default y if GCOV_PROFILE_PREREQS
+	help
+	  The SERIAL_GCOV will add Gcov profiling flags when kernel compiles.
+	  Say 'Y' here if you want the gcov data for the serial directory,
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index d056ee6cca33..17272733db95 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -3,6 +3,7 @@
 # Makefile for the kernel serial device drivers.
 #
 
+GCOV_PROFILE := $(CONFIG_SERIAL_GCOV)
 obj-$(CONFIG_SERIAL_CORE) += serial_core.o
 
 obj-$(CONFIG_SERIAL_EARLYCON) += earlycon.o
diff --git a/kernel/gcov/Kconfig b/kernel/gcov/Kconfig
index 3941a9c48f83..35b839879553 100644
--- a/kernel/gcov/Kconfig
+++ b/kernel/gcov/Kconfig
@@ -51,6 +51,21 @@ 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.
 
+config GCOV_PROFILE_PREREQS
+	bool "Profile Kernel for prereqs"
+	depends on !COMPILE_TEST
+	depends on GCOV_KERNEL
+	depends on !COMPILE_PROFILE_ALL
+	default y if GCOV_KERNEL && !COMPILE_TEST
+	help
+	  This options activates profiling for the specified kernel modules.
+
+	  When some modules need Gcov data, enable this config, then configure
+	  with gcov on the corresponding modules,The directories or files of
+	  these modules will be added profiling flags after kernel compile.
+
+	  If unsure, say N.
+
 choice
 	prompt "Specify GCOV format"
 	depends on GCOV_KERNEL
-- 
2.17.1