Re: [PATCH 2.6.12-rc6-mm1] add allowed CPUs check into find_idlest_{group|cpu}()

["M.Baris Demiray" <baris@labristeknoloji.com>]

[-- Attachment #1: Type: text/plain, Size: 2095 bytes --]


Nick Piggin wrote:
 > [...]
> Looks good, thanks. I'll test it here and queue it up to
> send to Andrew. Will you send me a Signed-off-by: line to
> go with that?

Ops, thanks. Latest one is appended again (also not wrapped this time) and..

o Add relevant checks into find_idlest_group() and find_idlest_cpu()
   to make them return only the groups that have allowed CPUs and allowed
   CPUs respectively.

Signed-off-by: M.Baris Demiray <baris@labristeknoloji.com>

--- linux-2.6.12-rc6-mm1/kernel/sched.c.orig	2005-06-08 00:28:59.000000000 +0000
+++ linux-2.6.12-rc6-mm1/kernel/sched.c	2005-06-08 20:45:25.000000000 +0000
@@ -1039,8 +1039,11 @@
  		int local_group;
  		int i;

+		/* Loop over if group has no CPUs allowed */
+		if (!cpus_intersects(group->cpumask, p->cpus_allowed))
+			continue;
+
  		local_group = cpu_isset(this_cpu, group->cpumask);
-		/* XXX: put a cpus allowed check */

  		/* Tally up the load of all CPUs in the group */
  		avg_load = 0;
@@ -1076,13 +1079,17 @@
  /*
   * find_idlest_queue - find the idlest runqueue among the cpus in group.
   */
-static int find_idlest_cpu(struct sched_group *group, int this_cpu)
+static int find_idlest_cpu(struct sched_group *group, struct task_struct *p,
+			   int this_cpu)
  {
  	unsigned long load, min_load = ULONG_MAX;
  	int idlest = -1;
  	int i;
+	cpumask_t allowed_cpus;

-	for_each_cpu_mask(i, group->cpumask) {
+	/* Traverse only the allowed CPUs */
+	cpus_and(allowed_cpus, group->cpumask, p->cpus_allowed);
+	for_each_cpu_mask(i, allowed_cpus) {
  		load = source_load(i, 0);

  		if (load < min_load || (load == min_load && i == this_cpu)) {
@@ -1124,7 +1131,7 @@
  		if (!group)
  			goto nextlevel;

-		new_cpu = find_idlest_cpu(group, cpu);
+		new_cpu = find_idlest_cpu(group, t, cpu);
  		if (new_cpu == -1 || new_cpu == cpu)
  			goto nextlevel;



-- 
"You have to understand, most of these people are not ready to be
unplugged. And many of them are no inert, so hopelessly dependent
on the system, that they will fight to protect it."
                                                         Morpheus

[-- Attachment #2: baris.vcf --]
[-- Type: text/x-vcard, Size: 342 bytes --]

begin:vcard
fn:M.Baris Demiray
n:Demiray;M.Baris
org:Labris Teknoloji
adr:;;Teknokent Silikon Bina No:24 ODTU;Ankara;;06531;Turkey
email;internet:baris@labristeknoloji.com
title:Yazilim Gelistirme Uzmani
tel;work:+903122101490
tel;fax:+903122101492
x-mozilla-html:FALSE
url:http://www.labristeknoloji.com
version:2.1
end:vcard