2020-09-23 18:23:12

by Nitesh Narayan Lal

[permalink] [raw]
Subject: [PATCH v2 2/4] sched/isolation: Extend nohz_full to isolate managed IRQs

Extend nohz_full feature set to include isolation from managed IRQS. This
is required specifically for setups that only uses nohz_full and still
requires isolation for maintaining lower latency for the listed CPUs.

Having this change will ensure that the kernel functions that were using
HK_FLAG_MANAGED_IRQ to derive cpumask for pinning various jobs/IRQs do not
enqueue anything on the CPUs listed under nohz_full.

Suggested-by: Frederic Weisbecker <[email protected]>
Signed-off-by: Nitesh Narayan Lal <[email protected]>
---
kernel/sched/isolation.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c
index 5a6ea03f9882..9df9598a9e39 100644
--- a/kernel/sched/isolation.c
+++ b/kernel/sched/isolation.c
@@ -141,7 +141,7 @@ static int __init housekeeping_nohz_full_setup(char *str)
unsigned int flags;

flags = HK_FLAG_TICK | HK_FLAG_WQ | HK_FLAG_TIMER | HK_FLAG_RCU |
- HK_FLAG_MISC | HK_FLAG_KTHREAD;
+ HK_FLAG_MISC | HK_FLAG_KTHREAD | HK_FLAG_MANAGED_IRQ;

return housekeeping_setup(str, flags);
}
--
2.18.2