Commit f4bb5705 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

sched/nohz: Remove unnecessarily complex error handling pattern from find_new_ilb() 



find_new_ilb() returns nr_cpu_ids on failure - which is the usual
cpumask bitops return pattern, but is weird & unnecessary in this
context: not only is it a global variable, it it is a +1 out of
bounds CPU index and also has different signedness ...

Its only user, kick_ilb(), then checks the return against nr_cpu_ids
to decide to return. There's no other use.

So instead of this, use a standard -1 return on failure to find an
idle CPU, as the argument is signed already.

Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Reviewed-by: default avatarJoel Fernandes (Google) <joel@joelfernandes.org>
Link: https://lore.kernel.org/r/20231006102518.2452758-4-mingo@kernel.org
parent b6dd6984

kernel/sched/fair.c

+2 −3
Original line number Diff line number Diff line
@@ -11528,7 +11528,7 @@ static inline int find_new_ilb(void) 
			return ilb_cpu;

	}



	return nr_cpu_ids;

	return -1;

}



/*
@@ -11549,8 +11549,7 @@ static void kick_ilb(unsigned int flags) 
		nohz.next_balance = jiffies+1;



	ilb_cpu = find_new_ilb();



	if (ilb_cpu >= nr_cpu_ids)

	if (ilb_cpu < 0)

		return;



	/*