On Tue, Mar 11, 2025 at 10:56:03AM +0100, David Marchand wrote:
> Rather than maintain a file in parallel of the code, symbols to be
> exported can be marked with a token RTE_EXPORT_*SYMBOL.
>
> From those marks, the build framework generates map files only for
> symbols actually compiled (which means that the WINDOWS_NO_EXPORT hack
> becomes unnecessary).
>
> The build framework directly creates a map file in the format that the
> linker expects (rather than converting from GNU linker to MSVC linker).
>
> Empty maps are allowed again as a replacement for drivers/version.map.
>
> The symbol check is updated to only support the new format.
>
> Signed-off-by: David Marchand <david.march...@redhat.com>
Some comments inline below.
/Bruce
> ---
> Changes since RFC v2:
> - because of MSVC limitations wrt macro passed via cmdline,
> used an internal header for defining RTE_EXPORT_* macros,
> - updated documentation and tooling,
>
> ---
> MAINTAINERS | 2 +
> buildtools/gen-version-map.py | 111 ++++++++++
> buildtools/map-list-symbol.sh | 10 +-
> buildtools/meson.build | 1 +
> config/meson.build | 2 +
> config/rte_export.h | 16 ++
> devtools/check-symbol-change.py | 90 +++++++++
> devtools/check-symbol-maps.sh | 14 --
> devtools/checkpatches.sh | 2 +-
> doc/guides/contributing/abi_versioning.rst | 224 ++-------------------
> drivers/meson.build | 94 +++++----
> drivers/version.map | 3 -
> lib/meson.build | 91 ++++++---
> 13 files changed, 371 insertions(+), 289 deletions(-)
> create mode 100755 buildtools/gen-version-map.py
> create mode 100644 config/rte_export.h
> create mode 100755 devtools/check-symbol-change.py
> delete mode 100644 drivers/version.map
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 312e6fcee5..04772951d3 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -95,6 +95,7 @@ F: devtools/check-maintainers.sh
> F: devtools/check-forbidden-tokens.awk
> F: devtools/check-git-log.sh
> F: devtools/check-spdx-tag.sh
> +F: devtools/check-symbol-change.py
> F: devtools/check-symbol-change.sh
> F: devtools/check-symbol-maps.sh
> F: devtools/checkpatches.sh
> @@ -127,6 +128,7 @@ F: config/
> F: buildtools/check-symbols.sh
> F: buildtools/chkincs/
> F: buildtools/call-sphinx-build.py
> +F: buildtools/gen-version-map.py
> F: buildtools/get-cpu-count.py
> F: buildtools/get-numa-count.py
> F: buildtools/list-dir-globs.py
> diff --git a/buildtools/gen-version-map.py b/buildtools/gen-version-map.py
> new file mode 100755
> index 0000000000..b160aa828b
> --- /dev/null
> +++ b/buildtools/gen-version-map.py
> @@ -0,0 +1,111 @@
> +#!/usr/bin/env python3
> +# SPDX-License-Identifier: BSD-3-Clause
> +# Copyright (c) 2024 Red Hat, Inc.
> +
> +"""Generate a version map file used by GNU or MSVC linker."""
> +
While it's an internal build script not to be run by users directly, I
believe a short one-line usage here might be useful, since the code below
is directly referencing sys.argv[N] values. That makes it easier for the
user to know what they are.
Alternatively, assign them to proper names at the top of the script e.g.:
scriptname, link_mode, abi_version_file, output, *input = sys.argv
Final alternative (which may be a bit overkill) is to use argparse.
> +import re
> +import sys
> +
> +# From rte_export.h
> +export_exp_sym_regexp =
> re.compile(r"^RTE_EXPORT_EXPERIMENTAL_SYMBOL\(([^,]+), ([0-9]+.[0-9]+)\)")
> +export_int_sym_regexp = re.compile(r"^RTE_EXPORT_INTERNAL_SYMBOL\(([^)]+)\)")
> +export_sym_regexp = re.compile(r"^RTE_EXPORT_SYMBOL\(([^)]+)\)")
> +# From rte_function_versioning.h
> +ver_sym_regexp = re.compile(r"^RTE_VERSION_SYMBOL\(([^,]+), [^,]+, ([^,]+),")
> +ver_exp_sym_regexp = re.compile(r"^RTE_VERSION_EXPERIMENTAL_SYMBOL\([^,]+,
> ([^,]+),")
> +default_sym_regexp = re.compile(r"^RTE_DEFAULT_SYMBOL\(([^,]+), [^,]+,
> ([^,]+),")
> +
> +with open(sys.argv[2]) as f:
> + abi = 'DPDK_{}'.format(re.match("([0-9]+).[0-9]", f.readline()).group(1))
> +
> +symbols = {}
> +
> +for file in sys.argv[4:]:
> + with open(file, encoding="utf-8") as f:
> + for ln in f.readlines():
> + node = None
> + symbol = None
> + comment = None
> + if export_exp_sym_regexp.match(ln):
> + node = 'EXPERIMENTAL'
> + symbol = export_exp_sym_regexp.match(ln).group(1)
> + comment = ' # added in
> {}'.format(export_exp_sym_regexp.match(ln).group(2))
> + elif export_int_sym_regexp.match(ln):
> + node = 'INTERNAL'
> + symbol = export_int_sym_regexp.match(ln).group(1)
> + elif export_sym_regexp.match(ln):
> + node = abi
> + symbol = export_sym_regexp.match(ln).group(1)
> + elif ver_sym_regexp.match(ln):
> + node = 'DPDK_{}'.format(ver_sym_regexp.match(ln).group(1))
> + symbol = ver_sym_regexp.match(ln).group(2)
> + elif ver_exp_sym_regexp.match(ln):
> + node = 'EXPERIMENTAL'
> + symbol = ver_exp_sym_regexp.match(ln).group(1)
> + elif default_sym_regexp.match(ln):
> + node =
> 'DPDK_{}'.format(default_sym_regexp.match(ln).group(1))
> + symbol = default_sym_regexp.match(ln).group(2)
> +
> + if not symbol:
> + continue
> +
> + if node not in symbols:
> + symbols[node] = {}
> + symbols[node][symbol] = comment
> +
> +if sys.argv[1] == 'msvc':
> + with open(sys.argv[3], "w") as outfile:
> + outfile.writelines(f"EXPORTS\n")
> + for key in (abi, 'EXPERIMENTAL', 'INTERNAL'):
> + if key not in symbols:
> + continue
> + for symbol in sorted(symbols[key].keys()):
> + outfile.writelines(f"\t{symbol}\n")
> + del symbols[key]
> +else:
> + with open(sys.argv[3], "w") as outfile:
> + local_token = False
> + for key in (abi, 'EXPERIMENTAL', 'INTERNAL'):
> + if key not in symbols:
> + continue
> + outfile.writelines(f"{key} {{\n\tglobal:\n\n")
> + for symbol in sorted(symbols[key].keys()):
> + if sys.argv[1] == 'mingw' and symbol.startswith('per_lcore'):
> + prefix = '__emutls_v.'
> + else:
> + prefix = ''
> + outfile.writelines(f"\t{prefix}{symbol};")
> + comment = symbols[key][symbol]
> + if comment:
> + outfile.writelines(f"{comment}")
> + outfile.writelines("\n")
How about using "" rather than None for the default comment so you can
always just do a print of "{prefix}{symbol};{comment}\n". The fact that
writelines doesn't output a "\n" is a little confusing here, so maybe use
"print" instead.
print("f\t{prefix}{symbol};{comment}", file=outfile)
> + outfile.writelines("\n")
> + if not local_token:
> + outfile.writelines("\tlocal: *;\n")
> + local_token = True
> + outfile.writelines("};\n")
> + del symbols[key]
> + for key in sorted(symbols.keys()):
> + outfile.writelines(f"{key} {{\n\tglobal:\n\n")
> + for symbol in sorted(symbols[key].keys()):
> + if sys.argv[1] == 'mingw' and symbol.startswith('per_lcore'):
> + prefix = '__emutls_v.'
> + else:
> + prefix = ''
> + outfile.writelines(f"\t{prefix}{symbol};")
> + comment = symbols[key][symbol]
> + if comment:
> + outfile.writelines(f"{comment}")
> + outfile.writelines("\n")
> + outfile.writelines(f"}} {abi};\n")
> + if not local_token:
> + outfile.writelines("\tlocal: *;\n")
> + local_token = True
> + del symbols[key]
> + # No exported symbol, add a catch all
> + if not local_token:
> + outfile.writelines(f"{abi} {{\n")
> + outfile.writelines("\tlocal: *;\n")
> + local_token = True
> + outfile.writelines("};\n")
> diff --git a/buildtools/map-list-symbol.sh b/buildtools/map-list-symbol.sh
> index eb98451d8e..0829df4be5 100755
> --- a/buildtools/map-list-symbol.sh
> +++ b/buildtools/map-list-symbol.sh
> @@ -62,10 +62,14 @@ for file in $@; do
> if (current_section == "") {
> next;
> }
> + symbol_version = current_version
> + if (/^[^}].*[^:*]; # added in /) {
> + symbol_version = $5
> + }
> if ("'$version'" != "") {
> - if ("'$version'" == "unset" && current_version != "") {
> + if ("'$version'" == "unset" && symbol_version != "") {
> next;
> - } else if ("'$version'" != "unset" && "'$version'" !=
> current_version) {
> + } else if ("'$version'" != "unset" && "'$version'" !=
> symbol_version) {
> next;
> }
> }
> @@ -73,7 +77,7 @@ for file in $@; do
> if ("'$symbol'" == "all" || $1 == "'$symbol'") {
> ret = 0;
> if ("'$quiet'" == "") {
> - print "'$file' "current_section" "$1"
> "current_version;
> + print "'$file' "current_section" "$1"
> "symbol_version;
> }
> if ("'$symbol'" != "all") {
> exit 0;
> diff --git a/buildtools/meson.build b/buildtools/meson.build
> index 4e2c1217a2..b745e9afa4 100644
> --- a/buildtools/meson.build
> +++ b/buildtools/meson.build
> @@ -16,6 +16,7 @@ else
> py3 = ['meson', 'runpython']
> endif
> echo = py3 + ['-c', 'import sys; print(*sys.argv[1:])']
> +gen_version_map = py3 + files('gen-version-map.py')
> list_dir_globs = py3 + files('list-dir-globs.py')
> map_to_win_cmd = py3 + files('map_to_win.py')
> sphinx_wrapper = py3 + files('call-sphinx-build.py')
> diff --git a/config/meson.build b/config/meson.build
> index f31fef216c..54657055fb 100644
> --- a/config/meson.build
> +++ b/config/meson.build
> @@ -303,8 +303,10 @@ endif
> # add -include rte_config to cflags
> if is_ms_compiler
> add_project_arguments('/FI', 'rte_config.h', language: 'c')
> + add_project_arguments('/FI', 'rte_export.h', language: 'c')
> else
> add_project_arguments('-include', 'rte_config.h', language: 'c')
> + add_project_arguments('-include', 'rte_export.h', language: 'c')
> endif
>
> # enable extra warnings and disable any unwanted warnings
> diff --git a/config/rte_export.h b/config/rte_export.h
> new file mode 100644
> index 0000000000..83d871fe11
> --- /dev/null
> +++ b/config/rte_export.h
> @@ -0,0 +1,16 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright (c) 2025 Red Hat, Inc.
> + */
> +
> +#ifndef RTE_EXPORT_H
> +#define RTE_EXPORT_H
> +
> +/* *Internal* macros for exporting symbols, used by the build system.
> + * For RTE_EXPORT_EXPERIMENTAL_SYMBOL, ver indicates the
> + * version this symbol was introduced in.
> + */
> +#define RTE_EXPORT_EXPERIMENTAL_SYMBOL(a, ver)
> +#define RTE_EXPORT_INTERNAL_SYMBOL(a)
> +#define RTE_EXPORT_SYMBOL(a)
> +
> +#endif /* RTE_EXPORT_H */
> diff --git a/devtools/check-symbol-change.py b/devtools/check-symbol-change.py
> new file mode 100755
> index 0000000000..09709e4f06
> --- /dev/null
> +++ b/devtools/check-symbol-change.py
> @@ -0,0 +1,90 @@
> +#!/usr/bin/env python3
> +# SPDX-License-Identifier: BSD-3-Clause
> +# Copyright (c) 2025 Red Hat, Inc.
> +
> +"""Check exported symbols change in a patch."""
> +
> +import re
> +import sys
> +
> +file_header_regexp = re.compile(r"^(\-\-\-|\+\+\+)
> [ab]/(lib|drivers)/([^/]+)/([^/]+)")
> +# From rte_export.h
> +export_exp_sym_regexp =
> re.compile(r"^.RTE_EXPORT_EXPERIMENTAL_SYMBOL\(([^,]+),")
> +export_int_sym_regexp =
> re.compile(r"^.RTE_EXPORT_INTERNAL_SYMBOL\(([^)]+)\)")
> +export_sym_regexp = re.compile(r"^.RTE_EXPORT_SYMBOL\(([^)]+)\)")
> +# TODO, handle versioned symbols from rte_function_versioning.h
> +# ver_sym_regexp = re.compile(r"^.RTE_VERSION_SYMBOL\(([^,]+), [^,]+,
> ([^,]+),")
> +# ver_exp_sym_regexp =
> re.compile(r"^.RTE_VERSION_EXPERIMENTAL_SYMBOL\([^,]+, ([^,]+),")
> +# default_sym_regexp = re.compile(r"^.RTE_DEFAULT_SYMBOL\(([^,]+), [^,]+,
> ([^,]+),")
> +
> +symbols = {}
> +
> +for file in sys.argv[1:]:
> + with open(file, encoding="utf-8") as f:
> + for ln in f.readlines():
> + if file_header_regexp.match(ln):
> + if file_header_regexp.match(ln).group(2) == "lib":
> + lib = '/'.join(file_header_regexp.match(ln).group(2, 3))
> + elif file_header_regexp.match(ln).group(3) == "intel":
> + lib = '/'.join(file_header_regexp.match(ln).group(2, 3,
> 4))
> + else:
> + lib = '/'.join(file_header_regexp.match(ln).group(2, 3))
> +
> + if lib not in symbols:
> + symbols[lib] = {}
> + continue
> +
> + if export_exp_sym_regexp.match(ln):
> + symbol = export_exp_sym_regexp.match(ln).group(1)
> + node = 'EXPERIMENTAL'
> + elif export_int_sym_regexp.match(ln):
> + node = 'INTERNAL'
> + symbol = export_int_sym_regexp.match(ln).group(1)
> + elif export_sym_regexp.match(ln):
> + symbol = export_sym_regexp.match(ln).group(1)
> + node = 'stable'
> + else:
> + continue
> +
> + if symbol not in symbols[lib]:
> + symbols[lib][symbol] = {}
> + added = ln[0] == '+'
> + if added and 'added' in symbols[lib][symbol] and node !=
> symbols[lib][symbol]['added']:
> + print(f"{symbol} in {lib} was found in multiple ABI, please
> check.")
> + if not added and 'removed' in symbols[lib][symbol] and node !=
> symbols[lib][symbol]['removed']:
> + print(f"{symbol} in {lib} was found in multiple ABI, please
> check.")
> + if added:
> + symbols[lib][symbol]['added'] = node
> + else:
> + symbols[lib][symbol]['removed'] = node
> +
> + for lib in sorted(symbols.keys()):
> + error = False
> + for symbol in sorted(symbols[lib].keys()):
> + if 'removed' not in symbols[lib][symbol]:
> + # Symbol addition
> + node = symbols[lib][symbol]['added']
> + if node == 'stable':
> + print(f"ERROR: {symbol} in {lib} has been added directly
> to stable ABI.")
> + error = True
> + else:
> + print(f"INFO: {symbol} in {lib} has been added to {node}
> ABI.")
> + continue
> +
> + if 'added' not in symbols[lib][symbol]:
> + # Symbol removal
> + node = symbols[lib][symbol]['added']
> + if node == 'stable':
> + print(f"INFO: {symbol} in {lib} has been removed from
> stable ABI.")
> + print(f"Please check it has gone though the deprecation
> process.")
> + continue
> +
> + if symbols[lib][symbol]['added'] ==
> symbols[lib][symbol]['removed']:
> + # Symbol was moved around
> + continue
> +
> + # Symbol modifications
> + added = symbols[lib][symbol]['added']
> + removed = symbols[lib][symbol]['removed']
> + print(f"INFO: {symbol} in {lib} is moving from {removed} to
> {added}")
> + print(f"Please check it has gone though the deprecation
> process.")
> diff --git a/devtools/check-symbol-maps.sh b/devtools/check-symbol-maps.sh
> index 6121f78ec6..fcd3931e5d 100755
> --- a/devtools/check-symbol-maps.sh
> +++ b/devtools/check-symbol-maps.sh
> @@ -60,20 +60,6 @@ if [ -n "$local_miss_maps" ] ; then
> ret=1
> fi
>
> -find_empty_maps ()
> -{
> - for map in $@ ; do
> - [ $(buildtools/map-list-symbol.sh $map | wc -l) != '0' ] || echo $map
> - done
> -}
> -
> -empty_maps=$(find_empty_maps $@)
> -if [ -n "$empty_maps" ] ; then
> - echo "Found empty maps:"
> - echo "$empty_maps"
> - ret=1
> -fi
> -
> find_bad_format_maps ()
> {
> abi_version=$(cut -d'.' -f 1 ABI_VERSION)
> diff --git a/devtools/checkpatches.sh b/devtools/checkpatches.sh
> index 003bb49e04..7dcac7c8c9 100755
> --- a/devtools/checkpatches.sh
> +++ b/devtools/checkpatches.sh
> @@ -33,7 +33,7 @@
> VOLATILE,PREFER_PACKED,PREFER_ALIGNED,PREFER_PRINTF,STRLCPY,\
> PREFER_KERNEL_TYPES,PREFER_FALLTHROUGH,BIT_MACRO,CONST_STRUCT,\
> SPLIT_STRING,LONG_LINE_STRING,C99_COMMENT_TOLERANCE,\
> LINE_SPACING,PARENTHESIS_ALIGNMENT,NETWORKING_BLOCK_COMMENT_STYLE,\
> -NEW_TYPEDEFS,COMPARISON_TO_NULL,AVOID_BUG"
> +NEW_TYPEDEFS,COMPARISON_TO_NULL,AVOID_BUG,EXPORT_SYMBOL"
> options="$options $DPDK_CHECKPATCH_OPTIONS"
>
> print_usage () {
> diff --git a/doc/guides/contributing/abi_versioning.rst
> b/doc/guides/contributing/abi_versioning.rst
> index 88dd776b4c..addbb24b9e 100644
> --- a/doc/guides/contributing/abi_versioning.rst
> +++ b/doc/guides/contributing/abi_versioning.rst
> @@ -58,12 +58,12 @@ persists over multiple releases.
>
> .. code-block:: none
>
> - $ head ./lib/acl/version.map
> + $ head ./build/lib/librte_acl_exports.map
I must admit I'm not a fan of these long filenames. How about just
"acl_exports.map"?
> DPDK_21 {
> global:
> ...
>
> - $ head ./lib/eal/version.map
> + $ head ./build/lib/librte_eal_exports.map
> DPDK_21 {
> global:
> ...
> @@ -77,7 +77,7 @@ that library.
>
> .. code-block:: none
>
> - $ head ./lib/acl/version.map
> + $ head ./build/lib/librte_acl_exports.map
> DPDK_21 {
> global:
> ...
> @@ -88,7 +88,7 @@ that library.
> } DPDK_21;
> ...
>
> - $ head ./lib/eal/version.map
> + $ head ./build/lib/librte_eal_exports.map
> DPDK_21 {
> global:
> ...
> @@ -100,12 +100,12 @@ how this may be done.
>
> .. code-block:: none
>
> - $ head ./lib/acl/version.map
> + $ head ./build/lib/librte_acl_exports.map
> DPDK_22 {
> global:
> ...
>
> - $ head ./lib/eal/version.map
> + $ head ./build/lib/librte_eal_exports.map
> DPDK_22 {
> global:
> ...
> @@ -134,8 +134,7 @@ linked to the DPDK.
>
> To support backward compatibility the ``rte_function_versioning.h``
> header file provides macros to use when updating exported functions. These
> -macros are used in conjunction with the ``version.map`` file for
> -a given library to allow multiple versions of a symbol to exist in a shared
> +macros allow multiple versions of a symbol to exist in a shared
> library so that older binaries need not be immediately recompiled.
>
> The macros are:
> @@ -169,6 +168,7 @@ Assume we have a function as follows
> * Create an acl context object for apps to
> * manipulate
> */
> + RTE_EXPORT_SYMBOL(rte_acl_create)
> struct rte_acl_ctx *
> rte_acl_create(const struct rte_acl_param *param)
> {
> @@ -187,6 +187,7 @@ private, is safe), but it also requires modifying the
> code as follows
> * Create an acl context object for apps to
> * manipulate
> */
> + RTE_EXPORT_SYMBOL(rte_acl_create)
> struct rte_acl_ctx *
> rte_acl_create(const struct rte_acl_param *param, int debug)
> {
> @@ -203,78 +204,16 @@ The addition of a parameter to the function is ABI
> breaking as the function is
> public, and existing application may use it in its current form. However, the
> compatibility macros in DPDK allow a developer to use symbol versioning so
> that
> multiple functions can be mapped to the same public symbol based on when an
> -application was linked to it. To see how this is done, we start with the
> -requisite libraries version map file. Initially the version map file for the
> acl
> -library looks like this
> +application was linked to it.
>
> -.. code-block:: none
> -
> - DPDK_21 {
> - global:
> -
> - rte_acl_add_rules;
> - rte_acl_build;
> - rte_acl_classify;
> - rte_acl_classify_alg;
> - rte_acl_classify_scalar;
> - rte_acl_create;
> - rte_acl_dump;
> - rte_acl_find_existing;
> - rte_acl_free;
> - rte_acl_ipv4vlan_add_rules;
> - rte_acl_ipv4vlan_build;
> - rte_acl_list_dump;
> - rte_acl_reset;
> - rte_acl_reset_rules;
> - rte_acl_set_ctx_classify;
> -
> - local: *;
> - };
> -
> -This file needs to be modified as follows
> -
> -.. code-block:: none
> -
> - DPDK_21 {
> - global:
> -
> - rte_acl_add_rules;
> - rte_acl_build;
> - rte_acl_classify;
> - rte_acl_classify_alg;
> - rte_acl_classify_scalar;
> - rte_acl_create;
> - rte_acl_dump;
> - rte_acl_find_existing;
> - rte_acl_free;
> - rte_acl_ipv4vlan_add_rules;
> - rte_acl_ipv4vlan_build;
> - rte_acl_list_dump;
> - rte_acl_reset;
> - rte_acl_reset_rules;
> - rte_acl_set_ctx_classify;
> -
> - local: *;
> - };
> -
> - DPDK_22 {
> - global:
> - rte_acl_create;
> -
> - } DPDK_21;
> -
> -The addition of the new block tells the linker that a new version node
> -``DPDK_22`` is available, which contains the symbol rte_acl_create, and
> inherits
> -the symbols from the DPDK_21 node. This list is directly translated into a
> -list of exported symbols when DPDK is compiled as a shared library.
> -
> -Next, we need to specify in the code which function maps to the
> rte_acl_create
> +We need to specify in the code which function maps to the rte_acl_create
> symbol at which versions. First, at the site of the initial symbol
> definition,
> we wrap the function with ``RTE_VERSION_SYMBOL``, passing the current ABI
> version,
> -the function return type, and the function name and its arguments.
> +the function return type, the function name and its arguments.
Good fix, though technically not relevant to this patch.
>
> .. code-block:: c
>
> + -RTE_EXPORT_SYMBOL(rte_acl_create)
> -struct rte_acl_ctx *
> -rte_acl_create(const struct rte_acl_param *param)
> +RTE_VERSION_SYMBOL(21, struct rte_acl_ctx *, rte_acl_create, (const struct
> rte_acl_param *param))
> @@ -293,6 +232,7 @@ We have now mapped the original rte_acl_create symbol to
> the original function
>
> Please see the section :ref:`Enabling versioning macros
> <enabling_versioning_macros>` to enable this macro in the meson/ninja build.
> +
Ditto.
> Next, we need to create the new version of the symbol. We create a new
> function name and implement it appropriately, then wrap it in a call to
> ``RTE_DEFAULT_SYMBOL``.
>
> @@ -312,9 +252,9 @@ The macro instructs the linker to create the new default
> symbol
> ``rte_acl_create@DPDK_22``, which points to the function named
> ``rte_acl_create_v22``
> (declared by the macro).
>
> -And that's it, on the next shared library rebuild, there will be two
> versions of
> -rte_acl_create, an old DPDK_21 version, used by previously built
> applications,
> -and a new DPDK_22 version, used by future built applications.
> +And that's it. On the next shared library rebuild, there will be two
> versions of rte_acl_create,
> +an old DPDK_21 version, used by previously built applications, and a new
> DPDK_22 version,
> +used by future built applications.
nit: not sure what others think but "future built" sounds strange to me?
How about "later built" or "newly built"?
>
> .. note::
>
> @@ -364,6 +304,7 @@ Assume we have an experimental function
> ``rte_acl_create`` as follows:
> * Create an acl context object for apps to
> * manipulate
> */
<snip>
