| Message ID | 1478028130-27500-1-git-send-email-wei.liu2@citrix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
>>> On 01.11.16 at 20:22, <wei.liu2@citrix.com> wrote: > The debug option in Config.mk affects hypervisor, tools and stubdom by > appending different flags to CFLAGS. Mini-os under extra is not > affected because it already has its own build system when it is > separated from xen.git. > > It is undesirable because now hypervisor build is affected by both > Kconfig and debug. > > Disentangle the semantics of debug by pushing relevant options to > individual sub-systems. > > For hypervisor, the flags previously added by debug option is now > controlled by CONFIG_DEBUG. > > For tools, flags are moved from config/*.mk into tools/Rules.mk. > > For stubdom, because it unilaterally sets debug=y before including > top-level Config.mk, we only need to move the debug build set of flags > into stubdom Makefile. > > Specifically there are some considerations on what flags are picked: > > 1. we don't need -fno-optimize-sibling-calls anymore because gcc doc > indicates that it is not enabled for -O1, which we already set in the > debug build. > 2. for tools we use -O0 -g3 in Rules.mk because they already take > precedence over the flags set in config/*.mk. > 3. for hypervisor we don't add -fno-omit-frame-pointer to debug build > because that's controlled by CONFIG_FRAME_POINTER. > > This patch doesn't intend to tune those flags, but to provide identical > set of effective flags as before. The debug option in Config.mk will > only affect tools components after this patch is applied. > > Signed-off-by: Wei Liu <wei.liu2@citrix.com> Acked-by: Jan Beulich <jbeulich@suse.com>
On Wed, Nov 02, 2016 at 02:53:32AM -0600, Jan Beulich wrote: > >>> On 01.11.16 at 20:22, <wei.liu2@citrix.com> wrote: > > The debug option in Config.mk affects hypervisor, tools and stubdom by > > appending different flags to CFLAGS. Mini-os under extra is not > > affected because it already has its own build system when it is > > separated from xen.git. > > > > It is undesirable because now hypervisor build is affected by both > > Kconfig and debug. > > > > Disentangle the semantics of debug by pushing relevant options to > > individual sub-systems. > > > > For hypervisor, the flags previously added by debug option is now > > controlled by CONFIG_DEBUG. > > > > For tools, flags are moved from config/*.mk into tools/Rules.mk. > > > > For stubdom, because it unilaterally sets debug=y before including > > top-level Config.mk, we only need to move the debug build set of flags > > into stubdom Makefile. > > > > Specifically there are some considerations on what flags are picked: > > > > 1. we don't need -fno-optimize-sibling-calls anymore because gcc doc > > indicates that it is not enabled for -O1, which we already set in the > > debug build. > > 2. for tools we use -O0 -g3 in Rules.mk because they already take > > precedence over the flags set in config/*.mk. > > 3. for hypervisor we don't add -fno-omit-frame-pointer to debug build > > because that's controlled by CONFIG_FRAME_POINTER. > > > > This patch doesn't intend to tune those flags, but to provide identical > > set of effective flags as before. The debug option in Config.mk will > > only affect tools components after this patch is applied. > > > > Signed-off-by: Wei Liu <wei.liu2@citrix.com> > > Acked-by: Jan Beulich <jbeulich@suse.com> > Thanks. I will push this patch along with the two other earlier patches after my OSSTest patch lands on production. Please speak up if anyone thinks that's a bad idea. Wei.
On Wed, Nov 02, 2016 at 10:13:28AM +0000, Wei Liu wrote: > On Wed, Nov 02, 2016 at 02:53:32AM -0600, Jan Beulich wrote: > > >>> On 01.11.16 at 20:22, <wei.liu2@citrix.com> wrote: > > > The debug option in Config.mk affects hypervisor, tools and stubdom by > > > appending different flags to CFLAGS. Mini-os under extra is not > > > affected because it already has its own build system when it is > > > separated from xen.git. > > > > > > It is undesirable because now hypervisor build is affected by both > > > Kconfig and debug. > > > > > > Disentangle the semantics of debug by pushing relevant options to > > > individual sub-systems. > > > > > > For hypervisor, the flags previously added by debug option is now > > > controlled by CONFIG_DEBUG. > > > > > > For tools, flags are moved from config/*.mk into tools/Rules.mk. > > > > > > For stubdom, because it unilaterally sets debug=y before including > > > top-level Config.mk, we only need to move the debug build set of flags > > > into stubdom Makefile. > > > > > > Specifically there are some considerations on what flags are picked: > > > > > > 1. we don't need -fno-optimize-sibling-calls anymore because gcc doc > > > indicates that it is not enabled for -O1, which we already set in the > > > debug build. > > > 2. for tools we use -O0 -g3 in Rules.mk because they already take > > > precedence over the flags set in config/*.mk. > > > 3. for hypervisor we don't add -fno-omit-frame-pointer to debug build > > > because that's controlled by CONFIG_FRAME_POINTER. > > > > > > This patch doesn't intend to tune those flags, but to provide identical > > > set of effective flags as before. The debug option in Config.mk will > > > only affect tools components after this patch is applied. > > > > > > Signed-off-by: Wei Liu <wei.liu2@citrix.com> > > > > Acked-by: Jan Beulich <jbeulich@suse.com> > > > > Thanks. > > I will push this patch along with the two other earlier patches after my > OSSTest patch lands on production. Please speak up if anyone thinks > that's a bad idea. > My osstest patch landed last night, so I've now pushed this patch and the other two. Wei.
diff --git a/config/StdGNU.mk b/config/StdGNU.mk index 39d36b2..6be8233 100644 --- a/config/StdGNU.mk +++ b/config/StdGNU.mk @@ -35,14 +35,6 @@ UTIL_LIBS = -lutil SONAME_LDFLAG = -soname SHLIB_LDFLAGS = -shared -ifneq ($(debug),y) -CFLAGS += -O2 -fomit-frame-pointer -else -# Less than -O1 produces bad code and large stack frames -CFLAGS += -O1 -fno-omit-frame-pointer -CFLAGS-$(gcc) += -fno-optimize-sibling-calls -endif - ifeq ($(lto),y) CFLAGS += -flto LDFLAGS-$(clang) += -plugin LLVMgold.so diff --git a/config/SunOS.mk b/config/SunOS.mk index 86a384d..0fe5f45 100644 --- a/config/SunOS.mk +++ b/config/SunOS.mk @@ -31,12 +31,5 @@ UTIL_LIBS = SONAME_LDFLAG = -h SHLIB_LDFLAGS = -R $(SunOS_LIBDIR) -shared -ifneq ($(debug),y) -CFLAGS += -O2 -fno-omit-frame-pointer -else -# Less than -O1 produces bad code and large stack frames -CFLAGS += -O1 -fno-omit-frame-pointer -endif - CFLAGS += -Wa,--divide -D_POSIX_C_SOURCE=200112L -D__EXTENSIONS__ diff --git a/stubdom/Makefile b/stubdom/Makefile index 571704d..2921f30 100644 --- a/stubdom/Makefile +++ b/stubdom/Makefile @@ -6,6 +6,8 @@ export XEN_OS=MiniOS export stubdom=y export debug=y +# Moved from config/StdGNU.mk +CFLAGS += -O1 -fno-omit-frame-pointer ifeq (,$(findstring clean,$(MAKECMDGOALS))) ifeq ($(wildcard $(MINI_OS)/Config.mk),) diff --git a/tools/Rules.mk b/tools/Rules.mk index 5a80fec..0e73690 100644 --- a/tools/Rules.mk +++ b/tools/Rules.mk @@ -138,9 +138,11 @@ SHLIB_libxenvchan = $(SHDEPS_libxenvchan) -Wl,-rpath-link=$(XEN_LIBVCHAN) ifeq ($(debug),y) # Disable optimizations and enable debugging information for macros -CFLAGS += -O0 -g3 +CFLAGS += -O0 -g3 -fno-omit-frame-pointer # But allow an override to -O0 in case Python enforces -D_FORTIFY_SOURCE=<n>. PY_CFLAGS += $(PY_NOOPT_CFLAGS) +else +CFLAGS += -O2 -fomit-frame-pointer endif LIBXL_BLKTAP ?= $(CONFIG_BLKTAP2) diff --git a/xen/Rules.mk b/xen/Rules.mk index a9fda71..08cc776 100644 --- a/xen/Rules.mk +++ b/xen/Rules.mk @@ -46,6 +46,12 @@ ALL_OBJS-y += $(BASEDIR)/xsm/built_in.o ALL_OBJS-y += $(BASEDIR)/arch/$(TARGET_ARCH)/built_in.o ALL_OBJS-$(CONFIG_CRYPTO) += $(BASEDIR)/crypto/built_in.o +ifeq ($(CONFIG_DEBUG),y) +CFLAGS += -O1 +else +CFLAGS += -O2 -fomit-frame-pointer +endif + CFLAGS += -nostdinc -fno-builtin -fno-common CFLAGS += -Werror -Wredundant-decls -Wno-pointer-arith CFLAGS += -pipe -g -D__XEN__ -include $(BASEDIR)/include/xen/config.h
The debug option in Config.mk affects hypervisor, tools and stubdom by appending different flags to CFLAGS. Mini-os under extra is not affected because it already has its own build system when it is separated from xen.git. It is undesirable because now hypervisor build is affected by both Kconfig and debug. Disentangle the semantics of debug by pushing relevant options to individual sub-systems. For hypervisor, the flags previously added by debug option is now controlled by CONFIG_DEBUG. For tools, flags are moved from config/*.mk into tools/Rules.mk. For stubdom, because it unilaterally sets debug=y before including top-level Config.mk, we only need to move the debug build set of flags into stubdom Makefile. Specifically there are some considerations on what flags are picked: 1. we don't need -fno-optimize-sibling-calls anymore because gcc doc indicates that it is not enabled for -O1, which we already set in the debug build. 2. for tools we use -O0 -g3 in Rules.mk because they already take precedence over the flags set in config/*.mk. 3. for hypervisor we don't add -fno-omit-frame-pointer to debug build because that's controlled by CONFIG_FRAME_POINTER. This patch doesn't intend to tune those flags, but to provide identical set of effective flags as before. The debug option in Config.mk will only affect tools components after this patch is applied. Signed-off-by: Wei Liu <wei.liu2@citrix.com> --- Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: George Dunlap <George.Dunlap@eu.citrix.com> Cc: Ian Jackson <ian.jackson@eu.citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Stefano Stabellini <sstabellini@kernel.org> Cc: Tim Deegan <tim@xen.org> Cc: Wei Liu <wei.liu2@citrix.com> Cc: Samuel Thibault <samuel.thibault@ens-lyon.org> --- config/StdGNU.mk | 8 -------- config/SunOS.mk | 7 ------- stubdom/Makefile | 2 ++ tools/Rules.mk | 4 +++- xen/Rules.mk | 6 ++++++ 5 files changed, 11 insertions(+), 16 deletions(-)