From: Tejun Heo <tj@kernel.org>
To: Petr Mladek <pmladek@suse.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Oleg Nesterov <oleg@redhat.com>, Ingo Molnar <mingo@redhat.com>,
Peter Zijlstra <peterz@infradead.org>,
Steven Rostedt <rostedt@goodmis.org>,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
Josh Triplett <josh@joshtriplett.org>,
Thomas Gleixner <tglx@linutronix.de>,
Linus Torvalds <torvalds@linux-foundation.org>,
Jiri Kosina <jkosina@suse.cz>, Borislav Petkov <bp@suse.de>,
Michal Hocko <mhocko@suse.cz>,
linux-mm@kvack.org, Vlastimil Babka <vbabka@suse.cz>,
live-patching@vger.kernel.org, linux-api@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [RFC v2 07/18] kthread: Allow to cancel kthread work
Date: Wed, 14 Oct 2015 13:30:39 -0400 [thread overview]
Message-ID: <20151014173039.GB12799@mtj.duckdns.org> (raw)
In-Reply-To: <20151014102022.GA2880@pathway.suse.cz>
Hello,
On Wed, Oct 14, 2015 at 12:20:22PM +0200, Petr Mladek wrote:
> IMHO, it would be great if it is easy to convert between the
> kthread worker and workqueues API. It will allow to choose
Sure, keep the APIs similar so that they can be easily converted back
and forth but that doesn't mean kthread_worker should be as complex as
workqueue. Workqueue is *really* complex partly for historical
reasons and partly because it has to serve all corner cases. Please
make something simple which is similar enough to enable easy miration.
That amount of complexity simply isn't necessary for kthread_worker.
...
> PS: I am not convinced that all my concerns were non-issues.
> For example, I agree that a race when queuing the same work
> to more kthread workers might look theoretical. On the other
> hand, the API allows it and it might be hard to debug. IMHO,
There are big differences in terms of complexity between ensuring
something like the above working correctly under all circumstances and
implementing a warning trap which would trigger well enough to warn
against unsupported usages. These are active trade-offs to make and
not particularly hard ones either. Let's please keep kthread_worker
simple.
Thanks.
--
tejun
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next prev parent reply other threads:[~2015-10-14 17:30 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-09-21 13:03 [RFC v2 00/18] kthread: Use kthread worker API more widely Petr Mladek
2015-09-21 13:03 ` [RFC v2 01/18] kthread: Allow to call __kthread_create_on_node() with va_list args Petr Mladek
2015-09-21 13:03 ` [RFC v2 02/18] kthread: Add create_kthread_worker*() Petr Mladek
2015-09-22 18:20 ` Tejun Heo
2015-09-21 13:03 ` [RFC v2 03/18] kthread: Add drain_kthread_worker() Petr Mladek
2015-09-22 18:26 ` Tejun Heo
2015-09-21 13:03 ` [RFC v2 04/18] kthread: Add destroy_kthread_worker() Petr Mladek
2015-09-22 18:30 ` Tejun Heo
2015-09-21 13:03 ` [RFC v2 05/18] kthread: Add pending flag to kthread work Petr Mladek
2015-09-21 13:03 ` [RFC v2 06/18] kthread: Initial support for delayed " Petr Mladek
2015-09-21 13:03 ` [RFC v2 07/18] kthread: Allow to cancel " Petr Mladek
2015-09-22 19:35 ` Tejun Heo
2015-09-25 11:26 ` Petr Mladek
2015-09-28 17:03 ` Tejun Heo
2015-10-02 15:43 ` Petr Mladek
2015-10-02 19:24 ` Tejun Heo
2015-10-05 10:07 ` Petr Mladek
2015-10-05 11:09 ` Petr Mladek
2015-10-07 9:21 ` Petr Mladek
2015-10-07 14:24 ` Tejun Heo
2015-10-14 10:20 ` Petr Mladek
2015-10-14 17:30 ` Tejun Heo [this message]
2015-09-21 13:03 ` [RFC v2 08/18] kthread: Allow to modify delayed " Petr Mladek
2015-09-21 13:03 ` [RFC v2 09/18] mm/huge_page: Convert khugepaged() into kthread worker API Petr Mladek
2015-09-22 20:26 ` Tejun Heo
2015-09-23 9:50 ` Petr Mladek
2015-09-21 13:03 ` [RFC v2 10/18] ring_buffer: Do no not complete benchmark reader too early Petr Mladek
2015-09-21 13:03 ` [RFC v2 11/18] ring_buffer: Fix more races when terminating the producer in the benchmark Petr Mladek
2015-09-21 13:03 ` [RFC v2 12/18] ring_buffer: Convert benchmark kthreads into kthread worker API Petr Mladek
2015-09-21 13:03 ` [RFC v2 13/18] rcu: Finish folding ->fqs_state into ->gp_state Petr Mladek
2015-09-21 13:03 ` [RFC v2 14/18] rcu: Store first_gp_fqs into struct rcu_state Petr Mladek
2015-09-21 13:03 ` [RFC v2 15/18] rcu: Clean up timeouts for forcing the quiescent state Petr Mladek
2015-09-21 13:03 ` [RFC v2 16/18] rcu: Check actual RCU_GP_FLAG_FQS when handling " Petr Mladek
2015-09-21 13:03 ` [RFC v2 17/18] rcu: Convert RCU gp kthreads into kthread worker API Petr Mladek
2015-09-28 17:14 ` Paul E. McKenney
2015-10-01 15:43 ` Petr Mladek
2015-10-01 16:33 ` Paul E. McKenney
2015-09-21 13:03 ` [RFC v2 18/18] kthread: Better support freezable kthread workers Petr Mladek
2015-09-22 20:32 ` [RFC v2 00/18] kthread: Use kthread worker API more widely Tejun Heo
2015-09-30 5:08 ` Paul E. McKenney
2015-10-01 15:59 ` Petr Mladek
2015-10-01 17:00 ` Paul E. McKenney
2015-10-02 12:00 ` Petr Mladek
2015-10-02 13:59 ` Paul E. McKenney
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