Re: [PATCH v9 2/2] examples/l3fwd-power: add PM QoS configuration

[lihuisong (C)]

Hi chengwen,

在 2024/9/10 10:26, fengchengwen 写道:
Hi Huisong,
On 2024/8/9 17:50, Huisong Li wrote:
Add PM QoS configuration to declease the delay after sleep in case of
entering deeper idle state.

Signed-off-by: Huisong Li <lihuis...@huawei.com>
Acked-by: Morten Brørup <m...@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 2bb6b092c3..9b386c3710 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"
@@ -2260,6 +2261,22 @@ 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",
suggest on core%u and use if (ret != 0)
Ack

and how about use warning, if current system don't support it, we just give a 
warning message
but let's it continue.


Because power lib is just supported and compiled on Linux.
And Linux always enable this feature. So Linux always support it.
I don't know what it would be like to compile l3fwd-power on windows.
But this is the another issue and other power APIs, like rte_power_init, 
are used directly in l3fwd-power without any condition.
So how about contiue to use error message?


+                               lcore_id);
+                       return ret;
+               }
+       }
+
        return ret;
  }
  
@@ -2299,6 +2316,13 @@ 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;
  }
  

.