[XEN][PATCH] coverage: add extended coverage capabilities

[Grygorii Strashko <grygorii_strashko@xxxxxxxx>]

From: Grygorii Strashko <grygorii_strashko@xxxxxxxx>

Added CONFIG_COVERAGE_EXTENDED to enable coverage for .init and lib code.
When enabled - Xen .init data will not be freed.

Signed-off-by: Grygorii Strashko <grygorii_strashko@xxxxxxxx>
---
 xen/Kconfig.debug          | 10 ++++++++++
 xen/Rules.mk               | 13 +++++++++++++
 xen/arch/arm/setup.c       |  2 ++
 xen/arch/x86/setup.c       |  4 ++++
 xen/common/libelf/Makefile |  4 +++-
 xen/common/libfdt/Makefile |  4 +++-
 6 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/xen/Kconfig.debug b/xen/Kconfig.debug
index d900d926c555..3e04e1a3992b 100644
--- a/xen/Kconfig.debug
+++ b/xen/Kconfig.debug
@@ -44,6 +44,16 @@ config COVERAGE
 
          If unsure, say N here.
 
+config COVERAGE_EXTENDED
+    bool "Extended Code coverage support"
+    depends on COVERAGE
+    default y
+    help
+      Enable Extended code coverage support which include .init and libs code.
+      The .init sections are not freed in this case.
+
+      If unsure, say N here.
+
 config CONDITION_COVERAGE
        bool "Condition coverage support"
        depends on COVERAGE && CC_HAS_MCDC
diff --git a/xen/Rules.mk b/xen/Rules.mk
index 2b28d1ac3c18..6d66a2332fb0 100644
--- a/xen/Rules.mk
+++ b/xen/Rules.mk
@@ -145,11 +145,18 @@ endif
 # Ensure that profile/coverage data is updated atomically
 $(call cc-option-add,cov-cflags-$(CONFIG_COVERAGE),CC,-fprofile-update=atomic)
 
+ifeq ($(CONFIG_COVERAGE_EXTENDED),y)
+$(nocov-y) $(extra-y): \
+    cov-cflags-y :=
+
+$(obj-y) $(obj-bin-y) $(extra-y) $(lib-y): _c_flags += $(cov-cflags-y)
+else
 # Reset cov-cflags-y in cases where an objects has another one as prerequisite
 $(nocov-y) $(filter %.init.o, $(obj-y) $(obj-bin-y) $(extra-y)): \
     cov-cflags-y :=
 
 $(non-init-objects): _c_flags += $(cov-cflags-y)
+endif
 
 ifeq ($(CONFIG_UBSAN),y)
 # Any -fno-sanitize= options need to come after any -fsanitize= options
@@ -260,6 +267,7 @@ $(obj)/%.o: $(src)/%.S FORCE
 
 
 quiet_cmd_obj_init_o = INIT_O  $@
+ifneq ($(CONFIG_COVERAGE_EXTENDED),y)
 define cmd_obj_init_o
     $(OBJDUMP) -h $< | while read idx name sz rest; do \
         case "$$name" in \
@@ -272,6 +280,11 @@ define cmd_obj_init_o
     done || exit $$?; \
     $(OBJCOPY) $(foreach s,$(SPECIAL_DATA_SECTIONS),--rename-section 
.$(s)=.init.$(s)) $< $@
 endef
+else
+define cmd_obj_init_o
+    $(OBJCOPY) $(foreach s,$(SPECIAL_DATA_SECTIONS),--rename-section 
.$(s)=.init.$(s)) $< $@
+endef
+endif
 
 $(filter %.init.o,$(obj-y) $(obj-bin-y) $(extra-y)): $(obj)/%.init.o: 
$(obj)/%.o FORCE
        $(call if_changed,obj_init_o)
diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
index 7ad870e382c2..900585eb7099 100644
--- a/xen/arch/arm/setup.c
+++ b/xen/arch/arm/setup.c
@@ -68,10 +68,12 @@ static __used void noreturn init_done(void)
 {
     int rc;
 
+#if !defined(CONFIG_COVERAGE_EXTENDED)
     /* Must be done past setting system_state. */
     unregister_init_virtual_region();
 
     free_init_memory();
+#endif
 
     /*
      * We have finished booting. Mark the section .data.ro_after_init
diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index 872a8c63f94a..05810fa67787 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -845,6 +845,7 @@ static void noreturn init_done(void)
 
     domain_unpause_by_systemcontroller(dom0);
 
+#if !defined(CONFIG_COVERAGE_EXTENDED)
     /* MUST be done prior to removing .init data. */
     unregister_init_virtual_region();
 
@@ -867,6 +868,9 @@ static void noreturn init_done(void)
     destroy_xen_mappings(start, end);
     init_xenheap_pages(__pa(start), __pa(end));
     printk("Freed %lukB init memory\n", (end - start) >> 10);
+#else
+    (void) end, (void) start, (void)va;
+#endif
 
     /* Mark .rodata/ro_after_init as RO.  Maybe reform the superpage. */
     modify_xen_mappings((unsigned long)&__2M_rodata_start,
diff --git a/xen/common/libelf/Makefile b/xen/common/libelf/Makefile
index 917d12b006f7..337a3a8e1b35 100644
--- a/xen/common/libelf/Makefile
+++ b/xen/common/libelf/Makefile
@@ -1,5 +1,7 @@
 obj-bin-y := libelf.o
-nocov-y += libelf.o
+ifneq ($(CONFIG_COVERAGE_EXTENDED),y)
+       nocov-y += libelf.o
+endif
 libelf-objs := libelf-tools.o libelf-loader.o libelf-dominfo.o
 
 SECTIONS := text data $(SPECIAL_DATA_SECTIONS)
diff --git a/xen/common/libfdt/Makefile b/xen/common/libfdt/Makefile
index 6ce679f98f47..8c62563ccdbc 100644
--- a/xen/common/libfdt/Makefile
+++ b/xen/common/libfdt/Makefile
@@ -5,7 +5,9 @@ SECTIONS := text data $(SPECIAL_DATA_SECTIONS)
 # For CONFIG_OVERLAY_DTB, libfdt functionalities will be needed during runtime.
 ifneq ($(CONFIG_OVERLAY_DTB),y)
 OBJCOPYFLAGS := $(foreach s,$(SECTIONS),--rename-section .$(s)=.init.$(s))
-nocov-y += libfdt.o
+ifneq ($(CONFIG_COVERAGE_EXTENDED),y)
+       nocov-y += libfdt.o
+endif
 endif
 
 obj-y += libfdt.o
-- 
2.34.1