[dpdk-stable] [PATCH v6] meter: provide experimental alias of API for old apps

[Ferruh Yigit]

On v20.02 some meter APIs have been matured and symbols moved from
EXPERIMENTAL to DPDK_20.0.1 block.

This can break the applications that were using these mentioned APIs on
v19.11. Although there is no modification on the APIs and the action is
positive and matures the APIs, the affect can be negative to
applications.

This patch provides aliasing by duplicating the existing and versioned
symbols as experimental.

Since symbols moved from DPDK_20.0.1 to DPDK_21 block in the v20.05, the
aliasing done between EXPERIMENTAL and DPDK_21.

With DPDK_21 ABI (DPDK v20.11) all aliasing will be removed and only
stable version of the APIs will remain.

Fixes: 30512af820fe ("meter: remove experimental flag from RFC4115 trTCM API")
Cc: stable at dpdk.org

Signed-off-by: Ferruh Yigit <ferruh.yigit at intel.com>
---
Cc: Neil Horman <nhorman at tuxdriver.com>
Cc: Thomas Monjalon <thomas at monjalon.net>
Cc: Luca Boccassi <bluca at debian.org>
Cc: David Marchand <david.marchand at redhat.com>
Cc: Bruce Richardson <bruce.richardson at intel.com>
Cc: Ian Stokes <ian.stokes at intel.com>
Cc: Eelco Chaudron <echaudro at redhat.com>
Cc: Andrzej Ostruszka <amo at semihalf.com>
Cc: Ray Kinsella <mdr at ashroe.eu>
Cc: cristian.dumitrescu at intel.com

v2:
* Commit log updated

v3:
* added suggested comment to VERSION_SYMBOL_EXPERIMENTAL macro

v4:
* update script name in commit log, remove empty line

v5:
* Patch has only meter library changes
* Aliasing moved into rte_meter_compat.c

v6:
* Move aliasing back to rte_meter.c
* Rename static function to have '__' prefix
* Add comment to alias code
---
 lib/librte_meter/meson.build           |  1 +
 lib/librte_meter/rte_meter.c           | 73 ++++++++++++++++++++++++--
 lib/librte_meter/rte_meter_version.map |  8 +++
 3 files changed, 79 insertions(+), 3 deletions(-)

diff --git a/lib/librte_meter/meson.build b/lib/librte_meter/meson.build
index 646fd4d43f..fce0368437 100644
--- a/lib/librte_meter/meson.build
+++ b/lib/librte_meter/meson.build
@@ -3,3 +3,4 @@
 
 sources = files('rte_meter.c')
 headers = files('rte_meter.h')
+use_function_versioning = true
diff --git a/lib/librte_meter/rte_meter.c b/lib/librte_meter/rte_meter.c
index da01429a8b..149cf58bdd 100644
--- a/lib/librte_meter/rte_meter.c
+++ b/lib/librte_meter/rte_meter.c
@@ -9,6 +9,7 @@
 #include <rte_common.h>
 #include <rte_log.h>
 #include <rte_cycles.h>
+#include <rte_function_versioning.h>
 
 #include "rte_meter.h"
 
@@ -119,8 +120,15 @@ rte_meter_trtcm_config(struct rte_meter_trtcm *m,
 	return 0;
 }
 
-int
-rte_meter_trtcm_rfc4115_profile_config(
+/*
+ *  ABI aliasing done for 'rte_meter_trtcm_rfc4115_profile_config'
+ *  to support both EXPERIMENTAL and DPDK_21 versions
+ *  This versioning will be removed on next ABI version (v20.11)
+ *  and '__rte_meter_trtcm_rfc4115_profile_config' will be restrored back to
+ *  'rte_meter_trtcm_rfc4115_profile_config' without versioning.
+ */
+static int
+__rte_meter_trtcm_rfc4115_profile_config(
 	struct rte_meter_trtcm_rfc4115_profile *p,
 	struct rte_meter_trtcm_rfc4115_params *params)
 {
@@ -145,7 +153,42 @@ rte_meter_trtcm_rfc4115_profile_config(
 }
 
 int
-rte_meter_trtcm_rfc4115_config(
+rte_meter_trtcm_rfc4115_profile_config_s(
+	struct rte_meter_trtcm_rfc4115_profile *p,
+	struct rte_meter_trtcm_rfc4115_params *params);
+int
+rte_meter_trtcm_rfc4115_profile_config_s(
+	struct rte_meter_trtcm_rfc4115_profile *p,
+	struct rte_meter_trtcm_rfc4115_params *params)
+{
+	return __rte_meter_trtcm_rfc4115_profile_config(p, params);
+}
+BIND_DEFAULT_SYMBOL(rte_meter_trtcm_rfc4115_profile_config, _s, 21);
+MAP_STATIC_SYMBOL(int rte_meter_trtcm_rfc4115_profile_config(struct rte_meter_trtcm_rfc4115_profile *p,
+		struct rte_meter_trtcm_rfc4115_params *params), rte_meter_trtcm_rfc4115_profile_config_s);
+
+int
+rte_meter_trtcm_rfc4115_profile_config_e(
+	struct rte_meter_trtcm_rfc4115_profile *p,
+	struct rte_meter_trtcm_rfc4115_params *params);
+int
+rte_meter_trtcm_rfc4115_profile_config_e(
+	struct rte_meter_trtcm_rfc4115_profile *p,
+	struct rte_meter_trtcm_rfc4115_params *params)
+{
+	return __rte_meter_trtcm_rfc4115_profile_config(p, params);
+}
+VERSION_SYMBOL_EXPERIMENTAL(rte_meter_trtcm_rfc4115_profile_config, _e);
+
+/*
+ *  ABI aliasing done for 'rte_meter_trtcm_rfc4115_config'
+ *  to support both EXPERIMENTAL and DPDK_21 versions
+ *  This versioning will be removed on next ABI version (v20.11)
+ *  and '__rte_meter_trtcm_rfc4115_config' will be restrored back to
+ *  'rte_meter_trtcm_rfc4115_config' without versioning.
+ */
+static int
+__rte_meter_trtcm_rfc4115_config(
 	struct rte_meter_trtcm_rfc4115 *m,
 	struct rte_meter_trtcm_rfc4115_profile *p)
 {
@@ -160,3 +203,27 @@ rte_meter_trtcm_rfc4115_config(
 
 	return 0;
 }
+
+int
+rte_meter_trtcm_rfc4115_config_s(struct rte_meter_trtcm_rfc4115 *m,
+	struct rte_meter_trtcm_rfc4115_profile *p);
+int
+rte_meter_trtcm_rfc4115_config_s(struct rte_meter_trtcm_rfc4115 *m,
+	struct rte_meter_trtcm_rfc4115_profile *p)
+{
+	return __rte_meter_trtcm_rfc4115_config(m, p);
+}
+BIND_DEFAULT_SYMBOL(rte_meter_trtcm_rfc4115_config, _s, 21);
+MAP_STATIC_SYMBOL(int rte_meter_trtcm_rfc4115_config(struct rte_meter_trtcm_rfc4115 *m,
+		 struct rte_meter_trtcm_rfc4115_profile *p), rte_meter_trtcm_rfc4115_config_s);
+
+int
+rte_meter_trtcm_rfc4115_config_e(struct rte_meter_trtcm_rfc4115 *m,
+	struct rte_meter_trtcm_rfc4115_profile *p);
+int
+rte_meter_trtcm_rfc4115_config_e(struct rte_meter_trtcm_rfc4115 *m,
+	struct rte_meter_trtcm_rfc4115_profile *p)
+{
+	return __rte_meter_trtcm_rfc4115_config(m, p);
+}
+VERSION_SYMBOL_EXPERIMENTAL(rte_meter_trtcm_rfc4115_config, _e);
diff --git a/lib/librte_meter/rte_meter_version.map b/lib/librte_meter/rte_meter_version.map
index 2c7dadbcac..b493bcebe9 100644
--- a/lib/librte_meter/rte_meter_version.map
+++ b/lib/librte_meter/rte_meter_version.map
@@ -20,4 +20,12 @@ DPDK_21 {
 	rte_meter_trtcm_rfc4115_color_blind_check;
 	rte_meter_trtcm_rfc4115_config;
 	rte_meter_trtcm_rfc4115_profile_config;
+
 } DPDK_20.0;
+
+EXPERIMENTAL {
+       global:
+
+	rte_meter_trtcm_rfc4115_config;
+	rte_meter_trtcm_rfc4115_profile_config;
+};
-- 
2.25.4