[PATCH v10 2/2] examples/l3fwd-power: add PM QoS configuration

[Konstantin Ananyev]

> > Add PM QoS configuration to declease the delay after sleep in case of
> > entering deeper idle state.
> >
> > Signed-off-by: Huisong Li <lihuisong at huawei.com>
> > Acked-by: Morten Brørup <mb at 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..b0ddb54ee2 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);
> 
> I wonder why it is set to all worker cores silently and unconditionally?
> Wouldn't it be a change from current behavior of the power library?
s/library/sample app/

> 
> > +		if (ret != 0) {
> > +			RTE_LOG(ERR, L3FWD_POWER,
> > +				"Failed to set strict resume latency on core%u.\n",
> > +				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;
> >  }
> >
> > --
> > 2.22.0