[v1] examples/power: add baseline mode to PMD power

  The PMD Power Management scheme currently has 3 modes,
scale, monitor and pause. However, it would be nice to
have a baseline mode for easy comparison of power savings
with and without these modes.

This patch adds a 'baseline' mode were the pmd power
management is not enabled. Use --pmg-mgmt=baseline.

Signed-off-by: David Hunt <david.hunt@intel.com>
---
 examples/l3fwd-power/main.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)
  

On 31-May-21 12:30 PM, David Hunt wrote:
> The PMD Power Management scheme currently has 3 modes,
> scale, monitor and pause. However, it would be nice to
> have a baseline mode for easy comparison of power savings
> with and without these modes.
> 
> This patch adds a 'baseline' mode were the pmd power
> management is not enabled. Use --pmg-mgmt=baseline.
> 
> Signed-off-by: David Hunt <david.hunt@intel.com>
> ---
>   examples/l3fwd-power/main.c | 10 ++++++++--
>   1 file changed, 8 insertions(+), 2 deletions(-)
> 
> diff --git a/examples/l3fwd-power/main.c b/examples/l3fwd-power/main.c
> index f8dfed1634..34b0eaa401 100644
> --- a/examples/l3fwd-power/main.c
> +++ b/examples/l3fwd-power/main.c
> @@ -1617,7 +1617,7 @@ print_usage(const char *prgname)
>   		" empty polls, full polls, and core busyness to telemetry\n"
>   		" --interrupt-only: enable interrupt-only mode\n"
>   		" --pmd-mgmt MODE: enable PMD power management mode. "
> -		"Currently supported modes: monitor, pause, scale\n",
> +		"Currently supported modes: baseline, monitor, pause, scale\n",
>   		prgname);
>   }
>   
> @@ -1714,6 +1714,7 @@ parse_pmd_mgmt_config(const char *name)
>   #define PMD_MGMT_MONITOR "monitor"
>   #define PMD_MGMT_PAUSE   "pause"
>   #define PMD_MGMT_SCALE   "scale"
> +#define PMD_MGMT_BASELINE  "baseline"
>   
>   	if (strncmp(PMD_MGMT_MONITOR, name, sizeof(PMD_MGMT_MONITOR)) == 0) {
>   		pmgmt_type = RTE_POWER_MGMT_TYPE_MONITOR;
> @@ -1729,6 +1730,10 @@ parse_pmd_mgmt_config(const char *name)
>   		pmgmt_type = RTE_POWER_MGMT_TYPE_SCALE;
>   		return 0;
>   	}
> +	if (strncmp(PMD_MGMT_BASELINE, name, sizeof(PMD_MGMT_BASELINE)) == 0) {
> +		pmgmt_type = -1;
> +		return 0;
> +	}

I don't particularly like the enum abuse, type safety exists for a 
reason :) perhaps just add a bool that enables/disables this? you're 
effectively doing that anyway with pmgmt_type >= 0.

>   	/* unknown PMD power management mode */
>   	return -1;
>   }
> @@ -2767,7 +2772,8 @@ main(int argc, char **argv)
>   						 "Fail to add ptype cb\n");
>   			}
>   
> -			if (app_mode == APP_MODE_PMD_MGMT) {
> +			if ((app_mode == APP_MODE_PMD_MGMT) &&
> +					(pmgmt_type >= 0)) {
>   				ret = rte_power_ethdev_pmgmt_queue_enable(
>   						lcore_id, portid, queueid,
>   						pmgmt_type);
>