The Energy Model gets more bits used in 'flags'. Avoid adding another
debugfs file just to print what is the status of a new flag. Simply
remove old debugfs files and add one generic which prints all flags
as a hex value.

Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
---
 kernel/power/energy_model.c | 24 +++++-------------------
 1 file changed, 5 insertions(+), 19 deletions(-)

diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c
index babefc72085d..092513575e4e 100644
--- a/kernel/power/energy_model.c
+++ b/kernel/power/energy_model.c
@@ -54,28 +54,15 @@ static int em_debug_cpus_show(struct seq_file *s, void *unused)
 }
 DEFINE_SHOW_ATTRIBUTE(em_debug_cpus);
 
-static int em_debug_units_show(struct seq_file *s, void *unused)
+static int em_debug_flags_show(struct seq_file *s, void *unused)
 {
 	struct em_perf_domain *pd = s->private;
-	char *units = (pd->flags & EM_PERF_DOMAIN_MILLIWATTS) ?
-		"milliWatts" : "bogoWatts";
 
-	seq_printf(s, "%s\n", units);
+	seq_printf(s, "%#lx\n", pd->flags);
 
 	return 0;
 }
-DEFINE_SHOW_ATTRIBUTE(em_debug_units);
-
-static int em_debug_skip_inefficiencies_show(struct seq_file *s, void *unused)
-{
-	struct em_perf_domain *pd = s->private;
-	int enabled = (pd->flags & EM_PERF_DOMAIN_SKIP_INEFFICIENCIES) ? 1 : 0;
-
-	seq_printf(s, "%d\n", enabled);
-
-	return 0;
-}
-DEFINE_SHOW_ATTRIBUTE(em_debug_skip_inefficiencies);
+DEFINE_SHOW_ATTRIBUTE(em_debug_flags);
 
 static void em_debug_create_pd(struct device *dev)
 {
@@ -89,9 +76,8 @@ static void em_debug_create_pd(struct device *dev)
 		debugfs_create_file("cpus", 0444, d, dev->em_pd->cpus,
 				    &em_debug_cpus_fops);
 
-	debugfs_create_file("units", 0444, d, dev->em_pd, &em_debug_units_fops);
-	debugfs_create_file("skip-inefficiencies", 0444, d, dev->em_pd,
-			    &em_debug_skip_inefficiencies_fops);
+	debugfs_create_file("flags", 0444, d, dev->em_pd,
+			    &em_debug_flags_fops);
 
 	/* Create a sub-directory for each performance state */
 	for (i = 0; i < dev->em_pd->nr_perf_states; i++)
-- 
2.17.1

Hi Lukasz,

IMO the debugfs files were fine as they were:
 - They offered information on units and inefficiencies without having
   to dig into the code to see which bit is for which flag.
 - I believe the artificial EM power values fit under bogoWatts as unit,
   so that part would still be correct.

On the other hand, your new file offers more information: we'd be able
to see in debugfs whether we're dealing with an artificial EM, despite
needing a bit more looking over the code to understand the output.

I don't have a strong opinion and the code looks fine, so:

Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>


On Monday 21 Mar 2022 at 09:57:26 (+0000), Lukasz Luba wrote:
> The Energy Model gets more bits used in 'flags'. Avoid adding another
> debugfs file just to print what is the status of a new flag. Simply
> remove old debugfs files and add one generic which prints all flags
> as a hex value.
> 
> Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
> ---
>  kernel/power/energy_model.c | 24 +++++-------------------
>  1 file changed, 5 insertions(+), 19 deletions(-)
> 
> diff --git a/kernel/power/energy_model.c b/kernel/power/energy_model.c
> index babefc72085d..092513575e4e 100644
> --- a/kernel/power/energy_model.c
> +++ b/kernel/power/energy_model.c
> @@ -54,28 +54,15 @@ static int em_debug_cpus_show(struct seq_file *s, void *unused)
>  }
>  DEFINE_SHOW_ATTRIBUTE(em_debug_cpus);
>  
> -static int em_debug_units_show(struct seq_file *s, void *unused)
> +static int em_debug_flags_show(struct seq_file *s, void *unused)
>  {
>  	struct em_perf_domain *pd = s->private;
> -	char *units = (pd->flags & EM_PERF_DOMAIN_MILLIWATTS) ?
> -		"milliWatts" : "bogoWatts";
>  
> -	seq_printf(s, "%s\n", units);
> +	seq_printf(s, "%#lx\n", pd->flags);
>  
>  	return 0;
>  }
> -DEFINE_SHOW_ATTRIBUTE(em_debug_units);
> -
> -static int em_debug_skip_inefficiencies_show(struct seq_file *s, void *unused)
> -{
> -	struct em_perf_domain *pd = s->private;
> -	int enabled = (pd->flags & EM_PERF_DOMAIN_SKIP_INEFFICIENCIES) ? 1 : 0;
> -
> -	seq_printf(s, "%d\n", enabled);
> -
> -	return 0;
> -}
> -DEFINE_SHOW_ATTRIBUTE(em_debug_skip_inefficiencies);
> +DEFINE_SHOW_ATTRIBUTE(em_debug_flags);
>  
>  static void em_debug_create_pd(struct device *dev)
>  {
> @@ -89,9 +76,8 @@ static void em_debug_create_pd(struct device *dev)
>  		debugfs_create_file("cpus", 0444, d, dev->em_pd->cpus,
>  				    &em_debug_cpus_fops);
>  
> -	debugfs_create_file("units", 0444, d, dev->em_pd, &em_debug_units_fops);
> -	debugfs_create_file("skip-inefficiencies", 0444, d, dev->em_pd,
> -			    &em_debug_skip_inefficiencies_fops);
> +	debugfs_create_file("flags", 0444, d, dev->em_pd,
> +			    &em_debug_flags_fops);
>  
>  	/* Create a sub-directory for each performance state */
>  	for (i = 0; i < dev->em_pd->nr_perf_states; i++)
> -- 
> 2.17.1
>

Hi Ionela,

Thank you for reviewing these patches.

On 4/4/22 17:02, Ionela Voinescu wrote:
> Hi Lukasz,
> 
> IMO the debugfs files were fine as they were:
>   - They offered information on units and inefficiencies without having
>     to dig into the code to see which bit is for which flag.
>   - I believe the artificial EM power values fit under bogoWatts as unit,
>     so that part would still be correct.
> 
> On the other hand, your new file offers more information: we'd be able
> to see in debugfs whether we're dealing with an artificial EM, despite
> needing a bit more looking over the code to understand the output.

I have consolidated them, so we would support more features in the flag
automatically when there will be a need.

In Android kernel we don't have unfortunately the debugfs compiled-in,
so this information is still only for kernel testing with some Linux
distro.

I have been thinking to switch into sysfs interface, so we could
have it in Android as well. This patch change adding a generic 'flags'
which would be more 'stable' (which is a requirement for sysfs contract)
is also a closer step into that direction. But that is for longer
discussion and not for this $subject.

> 
> I don't have a strong opinion and the code looks fine, so:
> 
> Reviewed-by: Ionela Voinescu <ionela.voinescu@arm.com>
>