Allow fetching CPU cycles usage for all lcores with a single request.
This endpoint is intended for repeated and frequent invocations by
external monitoring systems and therefore returns condensed data.
It consists of a single dictionary with three keys: "lcore_ids",
"total_cycles" and "busy_cycles" that are mapped to three arrays of
integer values. Each array has the same number of values, one per lcore,
in the same order.
Example:
--> /eal/lcore/usage
{
"/eal/lcore/usage": {
"lcore_ids": [
4,
5
],
"total_cycles": [
23846845590,
23900558914
],
"busy_cycles": [
21043446682,
21448837316
]
}
}
Cc: Morten Brørup <m...@smartsharesystems.com>
Signed-off-by: Robin Jarry <rja...@redhat.com>
Reviewed-by: Kevin Laatz <kevin.la...@intel.com>
---
Notes:
v7:
* Indentation fix
* Added release notes entry
doc/guides/rel_notes/release_23_03.rst | 5 +-
lib/eal/common/eal_common_lcore.c | 64 ++++++++++++++++++++++++++
2 files changed, 67 insertions(+), 2 deletions(-)
diff --git a/doc/guides/rel_notes/release_23_03.rst
b/doc/guides/rel_notes/release_23_03.rst
index 4c84d16a5f7e..3da483cf65f3 100644
--- a/doc/guides/rel_notes/release_23_03.rst
+++ b/doc/guides/rel_notes/release_23_03.rst
@@ -71,8 +71,9 @@ New Features
* **Added support for reporting lcore usage in applications.**
- * The ``/eal/lcore/list`` and ``/eal/lcore/info`` telemetry endpoints have
- been added to provide information similar to ``rte_lcore_dump()``.
+ * The ``/eal/lcore/list``, ``/eal/lcore/usage`` and ``/eal/lcore/info``
+ telemetry endpoints have been added to provide information similar to
+ ``rte_lcore_dump()``.
* Applications can register a callback at startup via
``rte_lcore_register_usage_cb()`` to provide lcore usage information.
diff --git a/lib/eal/common/eal_common_lcore.c
b/lib/eal/common/eal_common_lcore.c
index 4cc29ea6272f..d84852a23d68 100644
--- a/lib/eal/common/eal_common_lcore.c
+++ b/lib/eal/common/eal_common_lcore.c
@@ -573,6 +573,67 @@ handle_lcore_info(const char *cmd __rte_unused, const char
*params, struct rte_t
return rte_lcore_iterate(lcore_telemetry_info_cb, &info);
}
+struct lcore_telemetry_usage {
+ struct rte_tel_data *lcore_ids;
+ struct rte_tel_data *total_cycles;
+ struct rte_tel_data *busy_cycles;
+};
+
+static int
+lcore_telemetry_usage_cb(unsigned int lcore_id, void *arg)
+{
+ struct lcore_telemetry_usage *u = arg;
+ struct rte_lcore_usage usage;
+ rte_lcore_usage_cb usage_cb;
+
+ /* The callback may not set all the fields in the structure, so clear
it here. */
+ memset(&usage, 0, sizeof(usage));
+ /*
+ * Guard against concurrent modification of lcore_usage_cb.
+ * rte_lcore_register_usage_cb() should only be called once at
application init
+ * but nothing prevents and application to reset the callback to NULL.
+ */
+ usage_cb = lcore_usage_cb;
+ if (usage_cb != NULL && usage_cb(lcore_id, &usage) == 0) {
+ rte_tel_data_add_array_int(u->lcore_ids, lcore_id);
+ rte_tel_data_add_array_u64(u->total_cycles, usage.total_cycles);
+ rte_tel_data_add_array_u64(u->busy_cycles, usage.busy_cycles);
+ }
+
+ return 0;
+}
+
+static int
+handle_lcore_usage(const char *cmd __rte_unused,
+ const char *params __rte_unused,
+ struct rte_tel_data *d)
+{
+ struct lcore_telemetry_usage usage;
+ struct rte_tel_data *lcore_ids = rte_tel_data_alloc();
+ struct rte_tel_data *total_cycles = rte_tel_data_alloc();
+ struct rte_tel_data *busy_cycles = rte_tel_data_alloc();
+
+ if (!lcore_ids || !total_cycles || !busy_cycles) {
+ rte_tel_data_free(lcore_ids);
+ rte_tel_data_free(total_cycles);
+ rte_tel_data_free(busy_cycles);
+ return -ENOMEM;
+ }
+
+ rte_tel_data_start_dict(d);
+ rte_tel_data_start_array(lcore_ids, RTE_TEL_INT_VAL);
+ rte_tel_data_start_array(total_cycles, RTE_TEL_U64_VAL);
+ rte_tel_data_start_array(busy_cycles, RTE_TEL_U64_VAL);
+ rte_tel_data_add_dict_container(d, "lcore_ids", lcore_ids, 0);
+ rte_tel_data_add_dict_container(d, "total_cycles", total_cycles, 0);
+ rte_tel_data_add_dict_container(d, "busy_cycles", busy_cycles, 0);
+ usage.lcore_ids = lcore_ids;
+ usage.total_cycles = total_cycles;
+ usage.busy_cycles = busy_cycles;
+
+ return rte_lcore_iterate(lcore_telemetry_usage_cb, &usage);
+}
+
RTE_INIT(lcore_telemetry)
{
rte_telemetry_register_cmd(
@@ -581,5 +642,8 @@ RTE_INIT(lcore_telemetry)
rte_telemetry_register_cmd(
"/eal/lcore/info", handle_lcore_info,
"Returns lcore info. Parameters: int lcore_id");
+ rte_telemetry_register_cmd(
+ "/eal/lcore/usage", handle_lcore_usage,
+ "Returns lcore cycles usage. Takes no parameters");
}
#endif /* !RTE_EXEC_ENV_WINDOWS */
--
2.39.1
