[tip: sched/core] sched/fair: Remove select_idle_smt()

[tip-bot2 for Mel Gorman]

The following commit has been merged into the sched/core branch of tip:

Commit-ID:     6cd56ef1df399a004f90ecb682427f9964969fc9
Gitweb:        https://git.kernel.org/tip/6cd56ef1df399a004f90ecb682427f9964969fc9
Author:        Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
AuthorDate:    Mon, 25 Jan 2021 08:59:08 
Committer:     Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Wed, 17 Feb 2021 14:06:59 +01:00

sched/fair: Remove select_idle_smt()

In order to make the next patch more readable, and to quantify the
actual effectiveness of this pass, start by removing it.

Signed-off-by: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Reviewed-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx>
Link: https://lkml.kernel.org/r/20210125085909.4600-4-mgorman@xxxxxxxxxxxxxxxxxxx
---
 kernel/sched/fair.c | 30 ------------------------------
 1 file changed, 30 deletions(-)

diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 4c18ef6..6a0fc8a 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6114,27 +6114,6 @@ static int select_idle_core(struct task_struct *p, struct sched_domain *sd, int 
 	return -1;
 }
 
-/*
- * Scan the local SMT mask for idle CPUs.
- */
-static int select_idle_smt(struct task_struct *p, struct sched_domain *sd, int target)
-{
-	int cpu;
-
-	if (!static_branch_likely(&sched_smt_present))
-		return -1;
-
-	for_each_cpu(cpu, cpu_smt_mask(target)) {
-		if (!cpumask_test_cpu(cpu, p->cpus_ptr) ||
-		    !cpumask_test_cpu(cpu, sched_domain_span(sd)))
-			continue;
-		if (available_idle_cpu(cpu) || sched_idle_cpu(cpu))
-			return cpu;
-	}
-
-	return -1;
-}
-
 #else /* CONFIG_SCHED_SMT */
 
 static inline int select_idle_core(struct task_struct *p, struct sched_domain *sd, int target)
@@ -6142,11 +6121,6 @@ static inline int select_idle_core(struct task_struct *p, struct sched_domain *s
 	return -1;
 }
 
-static inline int select_idle_smt(struct task_struct *p, struct sched_domain *sd, int target)
-{
-	return -1;
-}
-
 #endif /* CONFIG_SCHED_SMT */
 
 /*
@@ -6336,10 +6310,6 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target)
 	if ((unsigned)i < nr_cpumask_bits)
 		return i;
 
-	i = select_idle_smt(p, sd, target);
-	if ((unsigned)i < nr_cpumask_bits)
-		return i;
-
 	return target;
 }