rte_metrics: unconditionally export rte_metrics_tel_xxx functions

lib/librte_metrics/meson.build +0 -2

@@ -4,11 +4,12 @@
 sources = files('rte_metrics.c')
 headers = files('rte_metrics.h')
 
-jansson = dependency('jansson', required: false, method: 'pkg-config')
-if jansson.found()

int32_t
rte_metrics_tel_reg_all_ethdev(int *metrics_register_done, int *reg_index_list) {
+#ifdef JANSSON

+ Bruce

On Mon, 22 Feb 2021 13:25:02 -0800, Jie wrote:
[...]

config/meson.build if is_freebsd · line 298

Quoted 12 lines

config/meson.build +4 -0

index 3cf560b8a..892bd9677 100644
@@ -292,6 +292,11 @@ if is_freebsd
 	add_project_arguments('-D__BSD_VISIBLE', language: 'c')
 endif
 
+jansson = dependency('jansson', required: false, method: 'pkg-config')
+if jansson.found()
+	dpdk_conf.set('RTE_HAVE_JANSSON', 1)
+endif

DPDK seems to prefer "HAS" for such macros.

Why not do this in lib/librte_telemetry/meson.build?

[...]

Quoted 8 lines

lib/librte_metrics/meson.build +0 -2

@@ -4,11 +4,12 @@
 sources = files('rte_metrics.c')
 headers = files('rte_metrics.h')
 
-jansson = dependency('jansson', required: false, method: 'pkg-config')
-if jansson.found()

lib/librte_metrics/meson.build line 12

Quoted 10 lines

lib/librte_metrics/meson.build +4 -4

+if dpdk_conf.has('RTE_HAVE_JANSSON')
 	ext_deps += jansson
-	sources += files('rte_metrics_telemetry.c')
-	headers += files('rte_metrics_telemetry.h')
-	deps += ['ethdev', 'telemetry']
-	includes += include_directories('../librte_telemetry')
 endif
+
+sources += files('rte_metrics_telemetry.c')
+headers += files('rte_metrics_telemetry.h')

Can be merged with definitions above.

[...]

Quoted 4 lines

int32_t
rte_metrics_tel_reg_all_ethdev(int *metrics_register_done, int *reg_index_list) {
+#ifdef JANSSON

Why not use RTE_HAS_JANSSON everywhere? (One more occurrence below.)

From: Jie Zhou <[email protected]>

This patch allows the same set of rte_metrics_tel_* functions to be exported no matter JANSSON is available or not, by doing following:
1. Leverage dpdk_conf to set configuration flag RTE_HAVE_JANSSON
when Jansson dependency is found.
2. In rte_metrics_telemetry.c, leverage RTE_HAVE_JANSSON to handle the
case when JANSSON is not available by adding stubs for all the instances.
3. In meson.build, per dpdk\doc\guides\rel_notes\release_20_05.rst,
it is claimed that "Telemetry library is no longer dependent on the external Jansson library, which allows Telemetry be enabled by default.", thus make the deps and includes of Telemetry as not conditional anymore.

V2 changes:
Address comments from Dmitry Kozlyuk <[email protected]> and Bruce Richardson <[email protected]>:
- Set dpdk.conf RTE_HAS_JANSSON in metrics meson.build
- Reduce #ifdef RTE_HAS_JANSSON blocks

Signed-off-by Jie Zhou <[email protected]>

---
 lib/librte_metrics/meson.build             | 12 ++---
 lib/librte_metrics/rte_metrics_telemetry.c | 60 +++++++++++++++++++++-
 lib/librte_metrics/rte_metrics_telemetry.h |  2 +-
 3 files changed, 65 insertions(+), 9 deletions(-)

lib/librte_metrics/meson.build +2 -2

index 28a8cc115..e543e4cdd 100644
@@ -1,14 +1,14 @@
 # SPDX-License-Identifier: BSD-3-Clause
 # Copyright(c) 2017 Intel Corporation
 
-sources = files('rte_metrics.c')
-headers = files('rte_metrics.h')
+sources = files('rte_metrics.c', 'rte_metrics_telemetry.c')
+headers = files('rte_metrics.h', 'rte_metrics_telemetry.h')
 
 jansson = dependency('jansson', required: false, method: 'pkg-config')
 if jansson.found()

lib/librte_metrics/rte_metrics_telemetry.c +58 -2

index b8ee56ef0..305ee271f 100644
@@ -2,8 +2,6 @@
  * Copyright(c) 2020 Intel Corporation
  */
 
-#include <jansson.h>
-
 #include <rte_ethdev.h>
 #include <rte_string_fns.h>
 #ifdef RTE_LIB_TELEMETRY

@@ -13,6 +11,7 @@
 #include "rte_metrics.h"
 #include "rte_metrics_telemetry.h"
 
+#ifdef RTE_HAS_JANSSON
 struct telemetry_metrics_data tel_met_data;
 
 int metrics_log_level;

@@ -541,3 +540,60 @@ RTE_INIT(metrics_ctor)
 			handle_ports_stats_values_by_name);
 #endif
 }
+#else
+int32_t
+rte_metrics_tel_reg_all_ethdev(int *metrics_register_done, int *reg_index_list)
+{
+	RTE_SET_USED(metrics_register_done);
+	RTE_SET_USED(reg_index_list);
+
+	return -ENOTSUP;
+}
+
+int32_t
+rte_metrics_tel_encode_json_format(struct telemetry_encode_param *ep,
+	char **json_buffer)
+{
+	RTE_SET_USED(ep);
+	RTE_SET_USED(json_buffer);
+
+	return -ENOTSUP;
+}
+
+int32_t
+rte_metrics_tel_get_ports_stats_json(struct telemetry_encode_param *ep,
+	int *reg_index, char **json_buffer)
+{
+	RTE_SET_USED(ep);
+	RTE_SET_USED(reg_index);
+	RTE_SET_USED(json_buffer);
+
+	return -ENOTSUP;
+}
+
+int32_t
+rte_metrics_tel_get_port_stats_ids(struct telemetry_encode_param *ep)
+{
+	RTE_SET_USED(ep);
+
+	return -ENOTSUP;
+}
+
+int32_t
+rte_metrics_tel_extract_data(struct telemetry_encode_param *ep, json_t *data)
+{
+	RTE_SET_USED(ep);
+	RTE_SET_USED(data);
+
+	return -ENOTSUP;
+}
+
+int32_t
+rte_metrics_tel_get_global_stats(struct telemetry_encode_param *ep)
+{
+	RTE_SET_USED(ep);
+
+	return -ENOTSUP;
+}
+
+#endif

lib/librte_metrics/rte_metrics_telemetry.h +1 -1

index 5dbb32ca0..2b6eb1ccc 100644
@@ -2,7 +2,7 @@
  * Copyright(c) 2020 Intel Corporation
  */
 
-#ifdef RTE_LIB_TELEMETRY
+#ifdef RTE_HAS_JANSSON
 #include <jansson.h>
 #else
 #define json_t void *

Signature · 1 line

2.30.0.vfs.0.2

V2 changes:
Address comments from Dmitry Kozlyuk <[email protected]> and Bruce Richardson <[email protected]>:
- Set dpdk.conf RTE_HAS_JANSSON in metrics meson.build
- Reduce #ifdef RTE_HAS_JANSSON blocks

V3 changes:
Address comment from Bruce Richardson <[email protected]>:
- Remove redundant includes line on librte_telemetry

From: Jie Zhou <[email protected]>

This patch allows the same set of rte_metrics_tel_* functions to be exported no matter JANSSON is available or not, by doing following:
1. Leverage dpdk_conf to set configuration flag RTE_HAVE_JANSSON

when Jansson dependency is found.
2. In rte_metrics_telemetry.c, leverage RTE_HAVE_JANSSON to handle the
case when JANSSON is not available by adding stubs for all the instances.
3. In meson.build, per dpdk\doc\guides\rel_notes\release_20_05.rst,

it is claimed that "Telemetry library is no longer dependent on the external Jansson library, which allows Telemetry be enabled by default.", thus make the deps and includes of Telemetry as not conditional anymore.

Signed-off-by Jie Zhou <[email protected]>

Acked-by Bruce Richardson <[email protected]>

Acked-by Dmitry Kozlyuk <[email protected]>

+#ifdef RTE_HAS_JANSSON
struct telemetry_metrics_data tel_met_data;