lkml.org 
[lkml]   [2017]   [Oct]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[tip:sched/core] sched/isolation: Provide a dynamic off-case to housekeeping_any_cpu()
Commit-ID:  9f0ca2d97ef0b5e966be2cfef26c7c094ec14e41
Gitweb: https://git.kernel.org/tip/9f0ca2d97ef0b5e966be2cfef26c7c094ec14e41
Author: Frederic Weisbecker <frederic@kernel.org>
AuthorDate: Fri, 27 Oct 2017 04:42:30 +0200
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Fri, 27 Oct 2017 09:55:26 +0200

sched/isolation: Provide a dynamic off-case to housekeeping_any_cpu()

housekeeping_any_cpu() doesn't handle correctly the case where
CONFIG_NO_HZ_FULL=y and no CPU is in nohz_full mode. So far no caller
needs this but let's prepare to avoid any future surprise.

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/1509072159-31808-4-git-send-email-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
include/linux/sched/isolation.h | 17 ++++++-----------
1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolation.h
index b7cfbc4..040df04 100644
--- a/include/linux/sched/isolation.h
+++ b/include/linux/sched/isolation.h
@@ -7,25 +7,20 @@

#ifdef CONFIG_NO_HZ_FULL
extern cpumask_var_t housekeeping_mask;
-
-static inline int housekeeping_any_cpu(void)
-{
- return cpumask_any_and(housekeeping_mask, cpu_online_mask);
-}
-
extern void __init housekeeping_init(void);
-
#else
+static inline void housekeeping_init(void) { }
+#endif /* CONFIG_NO_HZ_FULL */

static inline int housekeeping_any_cpu(void)
{
+#ifdef CONFIG_NO_HZ_FULL
+ if (tick_nohz_full_enabled())
+ return cpumask_any_and(housekeeping_mask, cpu_online_mask);
+#endif
return smp_processor_id();
}

-static inline void housekeeping_init(void) { }
-#endif /* CONFIG_NO_HZ_FULL */
-
-
static inline const struct cpumask *housekeeping_cpumask(void)
{
#ifdef CONFIG_NO_HZ_FULL
\
 
 \ /
  Last update: 2017-10-28 20:17    [W:0.119 / U:2.624 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site