From: Waiman Long <longman@redhat.com>
To: paulmck@kernel.org
Cc: Tejun Heo <tj@kernel.org>, Zefan Li <lizefan.x@bytedance.com>,
Johannes Weiner <hannes@cmpxchg.org>,
Frederic Weisbecker <frederic@kernel.org>,
Jonathan Corbet <corbet@lwn.net>,
Neeraj Upadhyay <quic_neeraju@quicinc.com>,
Joel Fernandes <joel@joelfernandes.org>,
Josh Triplett <josh@joshtriplett.org>,
Boqun Feng <boqun.feng@gmail.com>,
Steven Rostedt <rostedt@goodmis.org>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
Lai Jiangshan <jiangshanlai@gmail.com>,
Zqiang <qiang.zhang1211@gmail.com>,
Davidlohr Bueso <dave@stgolabs.net>,
Shuah Khan <shuah@kernel.org>,
cgroups@vger.kernel.org, linux-doc@vger.kernel.org,
linux-kernel@vger.kernel.org, rcu@vger.kernel.org,
linux-kselftest@vger.kernel.org, Mrunal Patel <mpatel@redhat.com>,
Ryan Phillips <rphillips@redhat.com>,
Brent Rowsell <browsell@redhat.com>,
Peter Hunt <pehunt@redhat.com>,
Cestmir Kalina <ckalina@redhat.com>,
Nicolas Saenz Julienne <nsaenz@kernel.org>,
Alex Gladkov <agladkov@redhat.com>,
Marcelo Tosatti <mtosatti@redhat.com>,
Phil Auld <pauld@redhat.com>,
Paul Gortmaker <paul.gortmaker@windriver.com>,
Daniel Bristot de Oliveira <bristot@kernel.org>,
Juri Lelli <juri.lelli@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Costa Shulyupin <cshulyup@redhat.com>
Subject: Re: [RFC PATCH 0/8] cgroup/cpuset: Support RCU_NOCB on isolated partitions
Date: Sat, 10 Feb 2024 20:46:34 -0500 [thread overview]
Message-ID: <099a0310-6805-4ad5-aa99-2589e768acd6@redhat.com> (raw)
In-Reply-To: <ad806d7c-91ec-4659-9348-1b0bb42dd417@paulmck-laptop>
On 1/19/24 05:24, Paul E. McKenney wrote:
> On Wed, Jan 17, 2024 at 11:35:03AM -0500, Waiman Long wrote:
>> This patch series is based on the RFC patch from Frederic [1]. Instead
>> of offering RCU_NOCB as a separate option, it is now lumped into a
>> root-only cpuset.cpus.isolation_full flag that will enable all the
>> additional CPU isolation capabilities available for isolated partitions
>> if set. RCU_NOCB is just the first one to this party. Additional dynamic
>> CPU isolation capabilities will be added in the future.
>>
>> The first 2 patches are adopted from Federic with minor twists to fix
>> merge conflicts and compilation issue. The rests are for implementing
>> the new cpuset.cpus.isolation_full interface which is essentially a flag
>> to globally enable or disable full CPU isolation on isolated partitions.
>> On read, it also shows the CPU isolation capabilities that are currently
>> enabled. RCU_NOCB requires that the rcu_nocbs option be present in
>> the kernel boot command line. Without that, the rcu_nocb functionality
>> cannot be enabled even if the isolation_full flag is set. So we allow
>> users to check the isolation_full file to verify that if the desired
>> CPU isolation capability is enabled or not.
>>
>> Only sanity checking has been done so far. More testing, especially on
>> the RCU side, will be needed.
> There has been some discussion of simplifying the (de-)offloading code
> to handle only offline CPUs. Along with some discussion of eliminating
> the (de-)offloading capability altogehter.
>
> We clearly should converge on the capability to be provided before
> exposing this to userspace. ;-)
Would you mind giving me a pointer to the discussion of simplifying the
de-offloading code to handle only offline CPUs?
Thanks,
Longman
next prev parent reply other threads:[~2024-02-11 1:46 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-01-17 16:35 [RFC PATCH 0/8] cgroup/cpuset: Support RCU_NOCB on isolated partitions Waiman Long
2024-01-17 16:35 ` [RFC PATCH 1/8] rcu/nocb: Pass a cpumask instead of a single CPU to offload/deoffload Waiman Long
2024-01-17 16:35 ` [RFC PATCH 2/8] rcu/nocb: Prepare to change nocb cpumask from CPU-hotplug protected cpuset caller Waiman Long
2024-01-17 16:35 ` [RFC PATCH 3/8] rcu/no_cb: Add rcu_nocb_enabled() to expose the rcu_nocb state Waiman Long
2024-01-17 16:35 ` [RFC PATCH 4/8] cgroup/cpuset: Better tracking of addition/deletion of isolated CPUs Waiman Long
2024-01-17 16:35 ` [RFC PATCH 5/8] cgroup/cpuset: Add cpuset.cpus.isolation_full Waiman Long
2024-01-17 16:35 ` [RFC PATCH 6/8] cgroup/cpuset: Enable dynamic rcu_nocb mode on isolated CPUs Waiman Long
2024-01-17 16:35 ` [RFC PATCH 7/8] cgroup/cpuset: Document the new cpuset.cpus.isolation_full control file Waiman Long
2024-01-17 16:35 ` [RFC PATCH 8/8] cgroup/cpuset: Update test_cpuset_prs.sh to handle cpuset.cpus.isolation_full Waiman Long
2024-01-17 17:07 ` [RFC PATCH 0/8] cgroup/cpuset: Support RCU_NOCB on isolated partitions Tejun Heo
2024-01-17 17:15 ` Waiman Long
2024-02-06 12:56 ` Frederic Weisbecker
2024-02-06 19:15 ` Marcelo Tosatti
2024-02-07 14:47 ` Frederic Weisbecker
2024-02-07 14:59 ` Marcelo Tosatti
2024-02-10 4:19 ` Waiman Long
2024-01-19 10:24 ` Paul E. McKenney
2024-02-11 1:46 ` Waiman Long [this message]
2024-01-22 15:07 ` Michal Koutný
2024-01-23 5:50 ` Waiman Long
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=099a0310-6805-4ad5-aa99-2589e768acd6@redhat.com \
--to=longman@redhat.com \
--cc=agladkov@redhat.com \
--cc=boqun.feng@gmail.com \
--cc=bristot@kernel.org \
--cc=browsell@redhat.com \
--cc=cgroups@vger.kernel.org \
--cc=ckalina@redhat.com \
--cc=corbet@lwn.net \
--cc=cshulyup@redhat.com \
--cc=dave@stgolabs.net \
--cc=frederic@kernel.org \
--cc=hannes@cmpxchg.org \
--cc=jiangshanlai@gmail.com \
--cc=joel@joelfernandes.org \
--cc=josh@joshtriplett.org \
--cc=juri.lelli@redhat.com \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=lizefan.x@bytedance.com \
--cc=mathieu.desnoyers@efficios.com \
--cc=mpatel@redhat.com \
--cc=mtosatti@redhat.com \
--cc=nsaenz@kernel.org \
--cc=paul.gortmaker@windriver.com \
--cc=pauld@redhat.com \
--cc=paulmck@kernel.org \
--cc=pehunt@redhat.com \
--cc=peterz@infradead.org \
--cc=qiang.zhang1211@gmail.com \
--cc=quic_neeraju@quicinc.com \
--cc=rcu@vger.kernel.org \
--cc=rostedt@goodmis.org \
--cc=rphillips@redhat.com \
--cc=shuah@kernel.org \
--cc=tj@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).