[PATCH v8 2/2] examples/l3fwd-power: add PM QoS configuration

[Huisong Li <lihuisong@huawei.com>]

Add PM QoS configuration to declease the delay after sleep in case of
entering deeper idle state.

Signed-off-by: Huisong Li <lihuisong@huawei.com>
Acked-by: Morten Brørup <mb@smartsharesystems.com>
---
 examples/l3fwd-power/main.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/examples/l3fwd-power/main.c b/examples/l3fwd-power/main.c
index fba11da7ca..d518e19467 100644
--- a/examples/l3fwd-power/main.c
+++ b/examples/l3fwd-power/main.c
@@ -47,6 +47,7 @@
 #include <rte_telemetry.h>
 #include <rte_power_pmd_mgmt.h>
 #include <rte_power_uncore.h>
+#include <rte_power_qos.h>
 
 #include "perf_core.h"
 #include "main.h"
@@ -2259,6 +2260,22 @@ init_power_library(void)
 			return -1;
 		}
 	}
+
+	RTE_LCORE_FOREACH(lcore_id) {
+		/*
+		 * Set the worker lcore's to have strict latency limit to allow
+		 * the CPU to enter the shallowest idle state.
+		 */
+		ret = rte_power_qos_set_cpu_resume_latency(lcore_id,
+					RTE_POWER_QOS_STRICT_LATENCY_VALUE);
+		if (ret < 0) {
+			RTE_LOG(ERR, L3FWD_POWER,
+				"Failed to set strict resume latency on CPU%u.\n",
+				lcore_id);
+			return ret;
+		}
+	}
+
 	return ret;
 }
 
@@ -2298,6 +2315,13 @@ deinit_power_library(void)
 			}
 		}
 	}
+
+	RTE_LCORE_FOREACH(lcore_id) {
+		/* Restore the original value in kernel. */
+		rte_power_qos_set_cpu_resume_latency(lcore_id,
+				RTE_POWER_QOS_RESUME_LATENCY_NO_CONSTRAINT);
+	}
+
 	return ret;
 }
 
-- 
2.22.0