lkml.org 
[lkml]   [2013]   [Mar]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4/4] nohz: New option to force all CPUs in full dynticks range
Date
Provide a new kernel config that forces all CPUs to be part
of the full dynticks range, except the boot one for timekeeping.

This is helpful for those who don't need a finegrained range
of full dynticks CPU and also for automated testing.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Geoff Levand <geoff@infradead.org>
Cc: Gilad Ben Yossef <gilad@benyossef.com>
Cc: Hakan Akkan <hakanakkan@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
---
kernel/time/Kconfig | 10 ++++++++++
kernel/time/tick-sched.c | 5 +++++
2 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig
index 5a87c03..407d771 100644
--- a/kernel/time/Kconfig
+++ b/kernel/time/Kconfig
@@ -98,6 +98,16 @@ config NO_HZ_EXTENDED

Say N.

+config NO_HZ_EXTENDED_ALL
+ bool "Full dynticks system on all CPUs"
+ depends on NO_HZ_EXTENDED
+ help
+ Force all CPUs to be full dynticks. The range specified in the
+ nohz_extended boot option will then be ignored.
+
+ Note the boot CPU will still be kept outside the range to handle
+ the timekeeping duty.
+
config HIGH_RES_TIMERS
bool "High Resolution Timer Support"
depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index a76d95e..0a3952c 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -161,10 +161,15 @@ static int __init tick_nohz_extended_setup(char *str)
int cpu;

alloc_bootmem_cpumask_var(&nohz_extended_mask);
+
+#ifdef CONFIG_NO_HZ_EXTENDED_ALL
+ cpumask_setall(nohz_extended_mask);
+#else
if (cpulist_parse(str, nohz_extended_mask) < 0) {
pr_warning("NOHZ: Incorrect nohz_extended cpumask\n");
return 1;
}
+#endif

cpu = smp_processor_id();
if (cpumask_test_cpu(cpu, nohz_extended_mask)) {
--
1.7.5.4


\
 
 \ /
  Last update: 2013-03-28 11:01    [W:0.165 / U:0.300 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site