sched/isolation: Move isolcpus= handling to the housekeeping code

We want to centralize the isolation features, to be done by the housekeeping
subsystem and scheduler domain isolation is a significant part of it.

No intended behaviour change, we just reuse the housekeeping cpumask
and core code.

Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Wanpeng Li <kernellwp@gmail.com>
Link: http://lkml.kernel.org/r/1509072159-31808-11-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 10 insertions, 1 deletions

diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 321cd7b4d817..a73ab95558f5 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -18,6 +18,7 @@
 #include <linux/cpufeature.h>
 #include <linux/tick.h>
 #include <linux/pm_qos.h>
+#include <linux/sched/isolation.h>
 
 #include "base.h"
 
@@ -271,8 +272,16 @@ static ssize_t print_cpus_isolated(struct device *dev,
                                   struct device_attribute *attr, char *buf)
 {
         int n = 0, len = PAGE_SIZE-2;
+        cpumask_var_t isolated;
 
-        n = scnprintf(buf, len, "%*pbl\n", cpumask_pr_args(cpu_isolated_map));
+        if (!alloc_cpumask_var(&isolated, GFP_KERNEL))
+                return -ENOMEM;
+
+        cpumask_andnot(isolated, cpu_possible_mask,
+                       housekeeping_cpumask(HK_FLAG_DOMAIN));
+        n = scnprintf(buf, len, "%*pbl\n", cpumask_pr_args(isolated));
+
+        free_cpumask_var(isolated);
 
         return n;
 }