From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by dpdk.org (Postfix) with ESMTP id AFAA91F7 for ; Wed, 1 Oct 2014 13:22:11 +0200 (CEST) Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga101.fm.intel.com with ESMTP; 01 Oct 2014 04:28:52 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,862,1389772800"; d="scan'208";a="394049308" Received: from irvmail001.ir.intel.com ([163.33.26.43]) by FMSMGA003.fm.intel.com with ESMTP; 01 Oct 2014 04:22:28 -0700 Received: from sivswdev02.ir.intel.com (sivswdev02.ir.intel.com [10.237.217.46]) by irvmail001.ir.intel.com (8.14.3/8.13.6/MailSET/Hub) with ESMTP id s91BSmQW007506; Wed, 1 Oct 2014 12:28:48 +0100 Received: from sivswdev02.ir.intel.com (localhost [127.0.0.1]) by sivswdev02.ir.intel.com with ESMTP id s91BSms8018786; Wed, 1 Oct 2014 12:28:48 +0100 Received: (from smonroy@localhost) by sivswdev02.ir.intel.com with id s91BSm3x018782; Wed, 1 Oct 2014 12:28:48 +0100 Date: Wed, 1 Oct 2014 12:28:48 +0100 From: Sergio Gonzalez Monroy To: Neil Horman Message-ID: <20141001112848.GA13501@sivswdev02.ir.intel.com> References: <1410809031-19114-2-git-send-email-nhorman@tuxdriver.com> <1412090280-9306-1-git-send-email-nhorman@tuxdriver.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1412090280-9306-1-git-send-email-nhorman@tuxdriver.com> User-Agent: Mutt/1.5.20 (2009-06-14) Cc: dev@dpdk.org Subject: Re: [dpdk-dev] [PATCH 1/4 v4] compat: Add infrastructure to support symbol versioning X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Oct 2014 11:22:12 -0000 Acked-by: Sergio Gonzalez Monroy On Tue, Sep 30, 2014 at 11:18:00AM -0400, Neil Horman wrote: > Add initial pass header files to support symbol versioning. > > --- > Change notes > v2) > * Fixed ifdef in rte_compat.h to test for RTE_BUILD_SHARED_LIB instead of the > non-existant RTE_SYMBOL_VERSIONING > > * Fixed VERSION_SYMBOL macro to add the needed extra @ to make versioning work > properly > > * Improved/Clarified documentation > > v3) > * Added missing macros to fully export the symver directive specification > > v4) > * Added macro definitions for !SHARED_LIB case > * Improved documentation > > Signed-off-by: Neil Horman > CC: Thomas Monjalon > CC: "Richardson, Bruce" > CC: "Gonzalez Monroy, Sergio" > --- > lib/Makefile | 1 + > lib/librte_compat/Makefile | 38 +++++++++++++++++ > lib/librte_compat/rte_compat.h | 96 ++++++++++++++++++++++++++++++++++++++++++ > mk/rte.lib.mk | 6 +++ > 4 files changed, 141 insertions(+) > create mode 100644 lib/librte_compat/Makefile > create mode 100644 lib/librte_compat/rte_compat.h > > diff --git a/lib/Makefile b/lib/Makefile > index 10c5bb3..a85b55b 100644 > --- a/lib/Makefile > +++ b/lib/Makefile > @@ -32,6 +32,7 @@ > include $(RTE_SDK)/mk/rte.vars.mk > > DIRS-$(CONFIG_RTE_LIBC) += libc > +DIRS-y += librte_compat > DIRS-$(CONFIG_RTE_LIBRTE_EAL) += librte_eal > DIRS-$(CONFIG_RTE_LIBRTE_MALLOC) += librte_malloc > DIRS-$(CONFIG_RTE_LIBRTE_RING) += librte_ring > diff --git a/lib/librte_compat/Makefile b/lib/librte_compat/Makefile > new file mode 100644 > index 0000000..3415c7b > --- /dev/null > +++ b/lib/librte_compat/Makefile > @@ -0,0 +1,38 @@ > +# BSD LICENSE > +# > +# Copyright(c) 2010-2014 Neil Horman > +# All rights reserved. > +# > +# Redistribution and use in source and binary forms, with or without > +# modification, are permitted provided that the following conditions > +# are met: > +# > +# * Redistributions of source code must retain the above copyright > +# notice, this list of conditions and the following disclaimer. > +# * Redistributions in binary form must reproduce the above copyright > +# notice, this list of conditions and the following disclaimer in > +# the documentation and/or other materials provided with the > +# distribution. > +# * Neither the name of Intel Corporation nor the names of its > +# contributors may be used to endorse or promote products derived > +# from this software without specific prior written permission. > +# > +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS > +# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT > +# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR > +# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT > +# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, > +# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT > +# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, > +# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY > +# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT > +# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE > +# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. > + > +include $(RTE_SDK)/mk/rte.vars.mk > + > + > +# install includes > +SYMLINK-y-include := rte_compat.h > + > +include $(RTE_SDK)/mk/rte.lib.mk > diff --git a/lib/librte_compat/rte_compat.h b/lib/librte_compat/rte_compat.h > new file mode 100644 > index 0000000..d99e362 > --- /dev/null > +++ b/lib/librte_compat/rte_compat.h > @@ -0,0 +1,96 @@ > +/*- > + * BSD LICENSE > + * > + * Copyright(c) 2010-2014 Neil Horman . > + * All rights reserved. > + * > + * Redistribution and use in source and binary forms, with or without > + * modification, are permitted provided that the following conditions > + * are met: > + * > + * * Redistributions of source code must retain the above copyright > + * notice, this list of conditions and the following disclaimer. > + * * Redistributions in binary form must reproduce the above copyright > + * notice, this list of conditions and the following disclaimer in > + * the documentation and/or other materials provided with the > + * distribution. > + * * Neither the name of Intel Corporation nor the names of its > + * contributors may be used to endorse or promote products derived > + * from this software without specific prior written permission. > + * > + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS > + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT > + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR > + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT > + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, > + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT > + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, > + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY > + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT > + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE > + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. > + */ > + > +#ifndef _RTE_COMPAT_H_ > +#define _RTE_COMPAT_H_ > + > +/* > + * This is just a stringification macro for use below. > + */ > +#define SA(x) #x > + > +#ifdef RTE_BUILD_SHARED_LIB > + > +/* > + * Provides backwards compatibility when updating exported functions. > + * When a symol is exported from a library to provide an API, it also provides a > + * calling convention (ABI) that is embodied in its name, return type, > + * arguments, etc. On occasion that function may need to change to accomodate > + * new functionality, behavior, etc. When that occurs, it is desireable to > + * allow for backwards compatibility for a time with older binaries that are > + * dynamically linked to the dpdk. to support that the __vsym and > + * VERSION_SYMBOL macros are created. They, in conjunction with the > + * _version.map file for a given library allow for multiple versions of > + * a symbol to exist in a shared library so that older binaries need not be > + * immediately recompiled. Their use is outlined in the following example: > + * Assumptions: DPDK 1.(X) contains a function int foo(char *string) > + * DPDK 1.(X+1) needs to change foo to be int foo(int index) > + * > + * To accomplish this: > + * 1) Edit lib//library_version.map to add a DPDK_1.(X+1) node, in which > + * foo is exported as a global symbol. > + * > + * 2) rename the existing function int foo(char *string) to > + * int __vsym foo_v18(char *string) > + * > + * 3) Add this macro immediately below the function > + * VERSION_SYMBOL(foo, _v18, 1.8); > + * > + * 4) Implement a new version of foo. > + * char foo(int value, int otherval) { ...} > + * > + * 5) Mark the newest version as the default version > + * BIND_DEFAULT_SYMBOL(foo, 1.9); > + * > + */ > +#define VERSION_SYMBOL(b, e, v) __asm__(".symver " SA(b) SA(e) ", "SA(b)"@DPDK_"SA(v)) > +#define BASE_SYMBOL(b, n) __asm__(".symver " SA(n) ", "SA(b)"@") > +#define BIND_DEFAULT_SYMBOL(b, v) __asm__(".symver " SA(b) ", "SA(b)"@@DPDK_"SA(v)) > +#define __vsym __attribute__((used)) > + > +#else > +/* > + * No symbol versioning in use > + */ > +#define VERSION_SYMBOL(b, e, v) > +#define __vsym > +#define BASE_SYMBOL(b, n) > +#define BIND_DEFAULT_SYMBOL(b, v) > + > +/* > + * RTE_BUILD_SHARED_LIB > + */ > +#endif > + > + > +#endif /* _RTE_COMPAT_H_ */ > diff --git a/mk/rte.lib.mk b/mk/rte.lib.mk > index f458258..82ac309 100644 > --- a/mk/rte.lib.mk > +++ b/mk/rte.lib.mk > @@ -40,8 +40,12 @@ VPATH += $(SRCDIR) > > ifeq ($(RTE_BUILD_SHARED_LIB),y) > LIB := $(patsubst %.a,%.so,$(LIB)) > + > +CPU_LDFLAGS += --version-script=$(EXPORT_MAP) > + > endif > > + > _BUILD = $(LIB) > _INSTALL = $(INSTALL-FILES-y) $(SYMLINK-FILES-y) $(RTE_OUTPUT)/lib/$(LIB) > _CLEAN = doclean > @@ -160,7 +164,9 @@ endif > $(RTE_OUTPUT)/lib/$(LIB): $(LIB) > @echo " INSTALL-LIB $(LIB)" > @[ -d $(RTE_OUTPUT)/lib ] || mkdir -p $(RTE_OUTPUT)/lib > +ifneq ($(LIB),) > $(Q)cp -f $(LIB) $(RTE_OUTPUT)/lib > +endif > > # > # Clean all generated files > -- > 1.9.3 >