From: Frederic Weisbecker <frederic@kernel.org>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Chris Metcalf <cmetcalf@mellanox.com>,
Thomas Gleixner <tglx@linutronix.de>,
Luiz Capitulino <lcapitulino@redhat.com>,
Christoph Lameter <cl@linux.com>,
"Paul E . McKenney" <paulmck@linux.vnet.ibm.com>,
Ingo Molnar <mingo@kernel.org>, Wanpeng Li <kernellwp@gmail.com>,
Mike Galbraith <efault@gmx.de>, Rik van Riel <riel@redhat.com>
Subject: [PATCH 5/5] sched/isolation: Document "nohz_offload" flag
Date: Thu, 21 Dec 2017 18:14:49 +0100 [thread overview]
Message-ID: <1513876489-11057-6-git-send-email-frederic@kernel.org> (raw)
In-Reply-To: <1513876489-11057-1-git-send-email-frederic@kernel.org>
Document the interface to offload the 1Hz scheduler tick in full
dynticks mode. Also improve the comment about the existing "nohz" flag
in order to differentiate its behaviour.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Christoph Lameter <cl@linux.com>
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: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <kernellwp@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
---
Documentation/admin-guide/kernel-parameters.txt | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 1683107..fcc5fd9 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -1745,7 +1745,12 @@
specified in the flag list (default: domain):
nohz
- Disable the tick when a single task runs.
+ Disable the tick when a single task runs. A residual 1Hz
+ tick remains to maintain scheduler stats alive.
+ nohz_offload
+ Like nohz but the residual 1Hz tick is offloaded to
+ housekeeping CPUs, leaving the CPU free of any tick if
+ nothing else requests it.
domain
Isolate from the general SMP balancing and scheduling
algorithms. Note that performing domain isolation this way
--
2.7.4
next prev parent reply other threads:[~2017-12-21 17:15 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-12-21 17:14 [PATCH 0/5] isolation: 1Hz residual tick offloading v2 Frederic Weisbecker
2017-12-21 17:14 ` [PATCH 1/5] sched: Rename init_rq_hrtick to hrtick_rq_init Frederic Weisbecker
2017-12-21 17:14 ` [PATCH 2/5] sched/isolation: Add scheduler tick offloading interface Frederic Weisbecker
2017-12-21 17:14 ` [PATCH 3/5] nohz: Allow to check if remote CPU tick is stopped Frederic Weisbecker
2017-12-21 17:14 ` [PATCH 4/5] sched/isolation: Residual 1Hz scheduler tick offload Frederic Weisbecker
2017-12-21 17:14 ` Frederic Weisbecker [this message]
-- strict thread matches above, loose matches on Subject: below --
2018-01-04 4:25 [GIT PULL] isolation: 1Hz residual tick offloading v3 Frederic Weisbecker
2018-01-04 4:25 ` [PATCH 5/5] sched/isolation: Document "nohz_offload" flag Frederic Weisbecker
2017-12-30 3:55 [PATCH 0/5] isolation: 1Hz residual tick offloading v3 Frederic Weisbecker
2017-12-30 3:55 ` [PATCH 5/5] sched/isolation: Document "nohz_offload" flag Frederic Weisbecker
2017-12-19 3:23 [RFC PATCH 0/5] isolation: 1Hz residual tick offloading Frederic Weisbecker
2017-12-19 3:23 ` [PATCH 5/5] sched/isolation: Document "nohz_offload" flag Frederic Weisbecker
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