[RESEND v7 2/3] ring: add telemetry cmd to list rings

[Jie Hai]

Add a telemetry command to list the rings used in the system.
An example using this command is shown below:

--> /ring/list
{
  "/ring/list": [
    "HT_0000:7d:00.2",
    "MP_mb_pool_0"
  ]
}

Signed-off-by: Jie Hai <haij...@huawei.com>
Acked-by: Konstantin Ananyev <konstantin.v.anan...@yandex.ru>
Reviewed-by: Honnappa Nagarahalli <honnappa.nagaraha...@arm.com>
Acked-by: Huisong Li <lihuis...@huawei.com>
Acked-by: Chengwen Feng <fengcheng...@huawei.com>
Acked-by: Morten Brørup <m...@smartsharesystems.com>
---
 lib/ring/meson.build |  1 +
 lib/ring/rte_ring.c  | 40 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/lib/ring/meson.build b/lib/ring/meson.build
index c20685c689ac..7fca958ed7fa 100644
--- a/lib/ring/meson.build
+++ b/lib/ring/meson.build
@@ -18,3 +18,4 @@ indirect_headers += files (
         'rte_ring_rts.h',
         'rte_ring_rts_elem_pvt.h',
 )
+deps += ['telemetry']
diff --git a/lib/ring/rte_ring.c b/lib/ring/rte_ring.c
index 057d25ff6f2f..6a10280fb093 100644
--- a/lib/ring/rte_ring.c
+++ b/lib/ring/rte_ring.c
@@ -22,6 +22,7 @@
 #include <rte_errno.h>
 #include <rte_string_fns.h>
 #include <rte_tailq.h>
+#include <rte_telemetry.h>
 
 #include "rte_ring.h"
 #include "rte_ring_elem.h"
@@ -418,3 +419,42 @@ rte_ring_lookup(const char *name)
 
        return r;
 }
+
+static void
+ring_walk(void (*func)(struct rte_ring *, void *), void *arg)
+{
+       struct rte_ring_list *ring_list;
+       struct rte_tailq_entry *tailq_entry;
+
+       ring_list = RTE_TAILQ_CAST(rte_ring_tailq.head, rte_ring_list);
+       rte_mcfg_tailq_read_lock();
+
+       TAILQ_FOREACH(tailq_entry, ring_list, next) {
+               (*func)((struct rte_ring *) tailq_entry->data, arg);
+       }
+
+       rte_mcfg_tailq_read_unlock();
+}
+
+static void
+ring_list_cb(struct rte_ring *r, void *arg)
+{
+       struct rte_tel_data *d = (struct rte_tel_data *)arg;
+
+       rte_tel_data_add_array_string(d, r->name);
+}
+
+static int
+ring_handle_list(const char *cmd __rte_unused,
+               const char *params __rte_unused, struct rte_tel_data *d)
+{
+       rte_tel_data_start_array(d, RTE_TEL_STRING_VAL);
+       ring_walk(ring_list_cb, d);
+       return 0;
+}
+
+RTE_INIT(ring_init_telemetry)
+{
+       rte_telemetry_register_cmd("/ring/list", ring_handle_list,
+               "Returns list of available rings. Takes no parameters");
+}
-- 
2.30.0