Re: [PATCH v4 04/20] cpumask: Introduce cpu_preferred_mask

[Shrikanth Hegde]

On 6/18/26 9:23 AM, Shrikanth Hegde wrote:
> Hi Yury.
>
> > > +void set_cpu_preferred(unsigned int cpu, bool preferred)
> > > +{
> > > +    if (!IS_ENABLED(CONFIG_PREFERRED_CPU))
> > > +        return;
> > > +
> > > +    assign_cpu((cpu), &__cpu_preferred_mask, (preferred));
> > > +}
> >
> > set_cpu_xxx() is a macro on purpose - it improves code generation
> > quite a lot. See 5c563ee90a22d. Can you keep set_cpu_preferred aligned
> > with the other set_cpu(), i.e. make it a macro?
>
> Ok. only reason was to avoid ifdeffery there.
>
> you mean below?
>
> #ifdef CONFIG_PREFERRED_CPU
> #else
> #endif
Ok. I misread your comment. I believe you meant to do like below.
preferred mask is always defined, either same as active or allocated.


diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index 30ea64cc1656..5a643d608ea6 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -1169,10 +1169,10 @@ void init_cpu_possible(const struct cpumask *src);
 #define set_cpu_present(cpu, present)  assign_cpu((cpu), &__cpu_present_mask, (present))
 #define set_cpu_active(cpu, active)    assign_cpu((cpu), &__cpu_active_mask, (active))
 #define set_cpu_dying(cpu, dying)      assign_cpu((cpu), &__cpu_dying_mask, (dying))
+#define set_cpu_preferred(cpu, preferred) assign_cpu((cpu), &__cpu_preferred_mask, (preferred))
 
 void set_cpu_online(unsigned int cpu, bool online);
 void set_cpu_possible(unsigned int cpu, bool possible);
-void set_cpu_preferred(unsigned int cpu, bool preferred);
 
 /**
  * to_cpumask - convert a NR_CPUS bitmap to a struct cpumask *
diff --git a/kernel/cpu.c b/kernel/cpu.c
index c196ba5d8b2a..d623a9c5554a 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -3159,14 +3159,6 @@ void set_cpu_possible(unsigned int cpu, bool possible)
        }
 }
 
-void set_cpu_preferred(unsigned int cpu, bool preferred)
-{
-       if (!IS_ENABLED(CONFIG_PREFERRED_CPU))
-               return;
-
-       assign_cpu((cpu), &__cpu_preferred_mask, (preferred));
-}
-
 /*
  * Activate the first processor.
  */