Add the boot option that will allow us to offload the 1Hz scheduler tick
to the housekeeping CPU.
Signed-off-by: Frederic Weisbecker <frede...@kernel.org>
Cc: Chris Metcalf <cmetc...@mellanox.com>
Cc: Christoph Lameter <c...@linux.com>
Cc: Luiz Capitulino <lcapitul...@redhat.com>
Cc: Mike Galbraith <efa...@gmx.de>
Cc: Paul E. McKenney <paul...@linux.vnet.ibm.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Rik van Riel <r...@redhat.com>
Cc: Thomas Gleixner <t...@linutronix.de>
Cc: Wanpeng Li <kernel...@gmail.com>
Cc: Ingo Molnar <mi...@kernel.org>
---
include/linux/sched/isolation.h | 3 ++-
kernel/sched/isolation.c | 6 ++++++
2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolation.h
index d849431..c831855 100644
--- a/include/linux/sched/isolation.h
+++ b/include/linux/sched/isolation.h
@@ -11,7 +11,8 @@ enum hk_flags {
HK_FLAG_MISC = (1 << 2),
HK_FLAG_SCHED = (1 << 3),
HK_FLAG_TICK = (1 << 4),
- HK_FLAG_DOMAIN = (1 << 5),
+ HK_FLAG_TICK_SCHED = (1 << 5),
+ HK_FLAG_DOMAIN = (1 << 6),
};
#ifdef CONFIG_CPU_ISOLATION
diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c
index b71b436..264ddcd 100644
--- a/kernel/sched/isolation.c
+++ b/kernel/sched/isolation.c
@@ -136,6 +136,12 @@ static int __init housekeeping_isolcpus_setup(char *str)
continue;
}
+ if (!strncmp(str, "nohz_offload,", 13)) {
+ str += 13;
+ flags |= HK_FLAG_TICK | HK_FLAG_TICK_SCHED;
+ continue;
+ }
+
if (!strncmp(str, "domain,", 7)) {
str += 7;
flags |= HK_FLAG_DOMAIN;
--
2.7.4
