Allow applications to register a callback that will be invoked in
rte_lcore_dump() and when requesting lcore info in the telemetry API.
The callback is expected to return a number between 0 and 100
representing the percentage of busy cycles spent over a fixed period of
time. The period of time is configured when registering the callback.
Cc: Bruce Richardson <bruce.richard...@intel.com>
Cc: Jerin Jacob <jer...@marvell.com>
Cc: Kevin Laatz <kevin.la...@intel.com>
Cc: Konstantin Ananyev <konstantin.v.anan...@yandex.ru>
Cc: Mattias Rönnblom <hof...@lysator.liu.se>
Cc: Morten Brørup <m...@smartsharesystems.com>
Signed-off-by: Robin Jarry <rja...@redhat.com>
---
lib/eal/common/eal_common_lcore.c | 37 ++++++++++++++++++++++++++++---
lib/eal/include/rte_lcore.h | 30 +++++++++++++++++++++++++
lib/eal/version.map | 1 +
3 files changed, 65 insertions(+), 3 deletions(-)
diff --git a/lib/eal/common/eal_common_lcore.c
b/lib/eal/common/eal_common_lcore.c
index 31e3965dc5ad..9a85fd8854df 100644
--- a/lib/eal/common/eal_common_lcore.c
+++ b/lib/eal/common/eal_common_lcore.c
@@ -420,14 +420,36 @@ rte_lcore_iterate(rte_lcore_iterate_cb cb, void *arg)
return ret;
}
+static rte_lcore_busy_percent_cb lcore_busy_cb;
+static unsigned int lcore_busy_period;
+
+void
+rte_lcore_register_busy_percent_cb(rte_lcore_busy_percent_cb cb, unsigned int
period)
+{
+ lcore_busy_cb = cb;
+ lcore_busy_period = period;
+}
+
+static int
+lcore_busy_percent(unsigned int lcore_id)
+{
+ int percent = -1;
+ if (lcore_busy_cb)
+ percent = lcore_busy_cb(lcore_id);
+ if (percent > 100)
+ percent = 100;
+ return percent;
+}
+
static int
lcore_dump_cb(unsigned int lcore_id, void *arg)
{
struct rte_config *cfg = rte_eal_get_configuration();
char cpuset[RTE_CPU_AFFINITY_STR_LEN];
+ char busy_str[16];
const char *role;
FILE *f = arg;
- int ret;
+ int ret, busy;
switch (cfg->lcore_role[lcore_id]) {
case ROLE_RTE:
@@ -446,9 +468,16 @@ lcore_dump_cb(unsigned int lcore_id, void *arg)
ret = eal_thread_dump_affinity(&lcore_config[lcore_id].cpuset, cpuset,
sizeof(cpuset));
- fprintf(f, "lcore %u, socket %u, role %s, cpuset %s%s\n", lcore_id,
+ busy = lcore_busy_percent(lcore_id);
+ if (busy < 0) {
+ snprintf(busy_str, sizeof(busy_str), "%s", "N/A");
+ } else {
+ snprintf(busy_str, sizeof(busy_str), "%d%% last %d sec",
+ busy, lcore_busy_period);
+ }
+ fprintf(f, "lcore %u, socket %u, role %s, cpuset %s%s, busy %s\n",
lcore_id,
rte_lcore_to_socket_id(lcore_id), role, cpuset,
- ret == 0 ? "" : "...");
+ ret == 0 ? "" : "...", busy_str);
return 0;
}
@@ -517,6 +546,8 @@ lcore_telemetry_info_cb(unsigned int lcore_id, void *arg)
rte_tel_data_add_dict_int(info->d, "socket",
rte_lcore_to_socket_id(lcore_id));
rte_tel_data_add_dict_string(info->d, "role", role);
rte_tel_data_add_dict_string(info->d, "cpuset", cpuset);
+ rte_tel_data_add_dict_int(info->d, "busy_percent",
lcore_busy_percent(lcore_id));
+ rte_tel_data_add_dict_int(info->d, "busy_period", lcore_busy_period);
return 0;
}
diff --git a/lib/eal/include/rte_lcore.h b/lib/eal/include/rte_lcore.h
index 6938c3fd7b81..b1223eaa12bf 100644
--- a/lib/eal/include/rte_lcore.h
+++ b/lib/eal/include/rte_lcore.h
@@ -328,6 +328,36 @@ typedef int (*rte_lcore_iterate_cb)(unsigned int lcore_id,
void *arg);
int
rte_lcore_iterate(rte_lcore_iterate_cb cb, void *arg);
+/**
+ * Callback to allow applications to report CPU utilization.
+ *
+ * @param lcore_id
+ * The lcore to consider.
+ * @return
+ * - A number between 0 and 100 representing the percentage of busy cycles
+ * over the last period for the given lcore_id.
+ * - -1 if the information is not available or if any error occurred.
+ */
+typedef int (*rte_lcore_busy_percent_cb)(unsigned int lcore_id);
+
+/**
+ * Register a callback from an application to be called in rte_lcore_dump()
+ * and the /eal/lcore/info telemetry endpoint handler.
+ *
+ * Applications are expected to return a number between 0 and 100 representing
+ * the percentage of busy cycles over the last period for the provided
lcore_id.
+ * The implementation details for computing such a ratio is specific to each
+ * application.
+ *
+ * @param cb
+ * The callback function.
+ * @param period
+ * The period in seconds over which the percentage of busy cycles will be
+ * reported by the application.
+ */
+__rte_experimental
+void rte_lcore_register_busy_percent_cb(rte_lcore_busy_percent_cb cb, unsigned
int period);
+
/**
* List all lcores.
*
diff --git a/lib/eal/version.map b/lib/eal/version.map
index 7ad12a7dc985..138537ee5835 100644
--- a/lib/eal/version.map
+++ b/lib/eal/version.map
@@ -440,6 +440,7 @@ EXPERIMENTAL {
rte_thread_detach;
rte_thread_equal;
rte_thread_join;
+ rte_lcore_register_busy_percent_cb;
};
INTERNAL {
--
2.38.1
