From 506f51cc0da7e057ac31e15048ba3b8015112226 Mon Sep 17 00:00:00 2001 From: Thomas Monjalon Date: Thu, 2 Jul 2015 23:03:40 +0200 Subject: [PATCH] mk: enable next abi preview When a change makes really hard to keep ABI compatibility, instead of waiting next release to break the ABI, it is smoother to introduce the new code as a preview and disable it when packaging. The flag RTE_NEXT_ABI must be used to "ifdef" the new code. When the release is out, a dynamically linked application can use the new shared libraries with the old ABI while developpers can prepare their application for the next ABI by reading the deprecation notice and easily testing the new code. When starting the next release cycle, the "ifdefs" will be removed and the ABI break will be marked by incrementing LIBABIVER. The map files will also be updated. The default value is enabled to be developer compliant. The packagers must disable it as done in pkg/dpdk.spec. When enabled, all shared library numbers are incremented by appending a minor .1 to the old ABI number. In the next release, only impacted libraries will have a major +1 increment. The impacted libraries must provide an alternative map file to use with this option. The ABI policy is updated. Signed-off-by: Thomas Monjalon Acked-by: Neil Horman --- config/common_bsdapp | 5 +++++ config/common_linuxapp | 5 +++++ doc/guides/guidelines/versioning.rst | 12 +++++++++--- mk/rte.lib.mk | 9 +++++---- pkg/dpdk.spec | 1 + scripts/validate-abi.sh | 2 ++ 6 files changed, 27 insertions(+), 7 deletions(-) diff --git a/config/common_bsdapp b/config/common_bsdapp index 1f5d1cfbd8..dfa61a323d 100644 --- a/config/common_bsdapp +++ b/config/common_bsdapp @@ -89,6 +89,11 @@ CONFIG_RTE_BUILD_SHARED_LIB=n CONFIG_RTE_BUILD_COMBINE_LIBS=n CONFIG_RTE_LIBNAME=intel_dpdk +# +# Use newest code breaking previous ABI +# +CONFIG_RTE_NEXT_ABI=y + # # Compile Environment Abstraction Layer # diff --git a/config/common_linuxapp b/config/common_linuxapp index 7a54ff8f38..1732b7046c 100644 --- a/config/common_linuxapp +++ b/config/common_linuxapp @@ -89,6 +89,11 @@ CONFIG_RTE_BUILD_SHARED_LIB=n CONFIG_RTE_BUILD_COMBINE_LIBS=n CONFIG_RTE_LIBNAME="intel_dpdk" +# +# Use newest code breaking previous ABI +# +CONFIG_RTE_NEXT_ABI=y + # # Compile Environment Abstraction Layer # diff --git a/doc/guides/guidelines/versioning.rst b/doc/guides/guidelines/versioning.rst index ea789cbc6d..8a739dd72b 100644 --- a/doc/guides/guidelines/versioning.rst +++ b/doc/guides/guidelines/versioning.rst @@ -55,12 +55,18 @@ being provided. The requirements for doing so are: #. At least 3 acknowledgments of the need to do so must be made on the dpdk.org mailing list. +#. The changes (including an alternative map file) must be gated with + the ``RTE_NEXT_ABI`` option, and provided with a deprecation notice at the + same time. + It will become the default ABI in the next release. + #. A full deprecation cycle, as explained above, must be made to offer downstream consumers sufficient warning of the change. -#. The ``LIBABIVER`` variable in the makefile(s) where the ABI changes are - incorporated must be incremented in parallel with the ABI changes - themselves. +#. At the beginning of the next release cycle, every ``RTE_NEXT_ABI`` + conditions will be removed, the ``LIBABIVER`` variable in the makefile(s) + where the ABI is changed will be incremented, and the map files will + be updated. Note that the above process for ABI deprecation should not be undertaken lightly. ABI stability is extremely important for downstream consumers of the diff --git a/mk/rte.lib.mk b/mk/rte.lib.mk index fff62a7679..f15de9b00d 100644 --- a/mk/rte.lib.mk +++ b/mk/rte.lib.mk @@ -37,11 +37,13 @@ include $(RTE_SDK)/mk/internal/rte.depdirs-pre.mk # VPATH contains at least SRCDIR VPATH += $(SRCDIR) -ifeq ($(CONFIG_RTE_BUILD_SHARED_LIB),y) +ifeq ($(CONFIG_RTE_BUILD_SHARED_LIB),y) LIB := $(patsubst %.a,%.so.$(LIBABIVER),$(LIB)) +ifeq ($(CONFIG_RTE_NEXT_ABI),y) +LIB := $(LIB).1 +endif CPU_LDFLAGS += --version-script=$(SRCDIR)/$(EXPORT_MAP) - endif @@ -167,12 +169,11 @@ endif # install lib in $(RTE_OUTPUT)/lib # $(RTE_OUTPUT)/lib/$(LIB): $(LIB) - $(eval LIBSONAME := $(basename $(LIB))) @echo " INSTALL-LIB $(LIB)" @[ -d $(RTE_OUTPUT)/lib ] || mkdir -p $(RTE_OUTPUT)/lib $(Q)cp -f $(LIB) $(RTE_OUTPUT)/lib ifeq ($(CONFIG_RTE_BUILD_SHARED_LIB),y) - $(Q)ln -s -f $< $(RTE_OUTPUT)/lib/$(LIBSONAME) + $(Q)ln -s -f $< $(basename $(basename $@)) endif # diff --git a/pkg/dpdk.spec b/pkg/dpdk.spec index 5f6ec6a2d0..fb71ccc456 100644 --- a/pkg/dpdk.spec +++ b/pkg/dpdk.spec @@ -82,6 +82,7 @@ make O=%{target} T=%{target} config sed -ri 's,(RTE_MACHINE=).*,\1%{machine},' %{target}/.config sed -ri 's,(RTE_APP_TEST=).*,\1n,' %{target}/.config sed -ri 's,(RTE_BUILD_SHARED_LIB=).*,\1y,' %{target}/.config +sed -ri 's,(RTE_NEXT_ABI=).*,\1n,' %{target}/.config sed -ri 's,(LIBRTE_VHOST=).*,\1y,' %{target}/.config sed -ri 's,(LIBRTE_PMD_PCAP=).*,\1y,' %{target}/.config sed -ri 's,(LIBRTE_PMD_XENVIRT=).*,\1y,' %{target}/.config diff --git a/scripts/validate-abi.sh b/scripts/validate-abi.sh index 1747b8b3e1..4476433ead 100755 --- a/scripts/validate-abi.sh +++ b/scripts/validate-abi.sh @@ -157,6 +157,7 @@ git checkout $TAG1 # Make sure we configure SHARED libraries # Also turn off IGB and KNI as those require kernel headers to build sed -i -e"$ a\CONFIG_RTE_BUILD_SHARED_LIB=y" config/defconfig_$TARGET +sed -i -e"$ a\CONFIG_RTE_NEXT_ABI=n" config/defconfig_$TARGET sed -i -e"$ a\CONFIG_RTE_EAL_IGB_UIO=n" config/defconfig_$TARGET sed -i -e"$ a\CONFIG_RTE_LIBRTE_KNI=n" config/defconfig_$TARGET @@ -198,6 +199,7 @@ git checkout $TAG2 # Make sure we configure SHARED libraries # Also turn off IGB and KNI as those require kernel headers to build sed -i -e"$ a\CONFIG_RTE_BUILD_SHARED_LIB=y" config/defconfig_$TARGET +sed -i -e"$ a\CONFIG_RTE_NEXT_ABI=n" config/defconfig_$TARGET sed -i -e"$ a\CONFIG_RTE_EAL_IGB_UIO=n" config/defconfig_$TARGET sed -i -e"$ a\CONFIG_RTE_LIBRTE_KNI=n" config/defconfig_$TARGET -- 2.20.1