From: Thomas Gleixner <tglx@linutronix.de>
To: Eric Dumazet <edumazet@google.com>, Will Deacon <will@kernel.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>,
the arch/x86 maintainers <x86@kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
Peter Zijlstra <peterz@infradead.org>
Subject: Re: Confused about hlist_unhashed_lockless()
Date: Fri, 31 Jan 2020 20:47:23 +0100 [thread overview]
Message-ID: <87blqj4ddg.fsf@nanos.tec.linutronix.de> (raw)
In-Reply-To: <CANn89iJNgPOzCdc-7QoC+dawJVn7tLQxmrx58GL8PT9rDVT2hA@mail.gmail.com>
Eric Dumazet <edumazet@google.com> writes:
> On Fri, Jan 31, 2020 at 9:21 AM Will Deacon <will@kernel.org> wrote:
>> Without serialisation, timer_pending() as currently implemented does
>> not reliably tell you whether the timer is in the hlist. Is that not a
>> problem?
>
> No it is not a problem.
Even if we would take the base lock then this is just a snapshot, which
can be wrong at the moment the lock is dropped. So why bother?
Thanks,
tglx
next prev parent reply other threads:[~2020-01-31 19:47 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-31 16:43 Will Deacon
2020-01-31 16:48 ` Eric Dumazet
2020-01-31 16:57 ` Will Deacon
2020-01-31 17:06 ` Eric Dumazet
2020-01-31 17:20 ` Will Deacon
2020-01-31 17:33 ` Eric Dumazet
2020-01-31 18:32 ` Will Deacon
2020-01-31 19:47 ` Thomas Gleixner [this message]
2020-01-31 20:52 ` Paul E. McKenney
2020-01-31 18:43 ` Peter Zijlstra
2020-01-31 18:48 ` Eric Dumazet
2020-01-31 18:52 ` Eric Dumazet
2020-01-31 20:53 ` Paul E. McKenney
2020-01-31 21:04 ` Eric Dumazet
2020-01-31 21:19 ` Paul E. McKenney
2020-02-03 15:45 ` David Laight
2020-02-03 15:54 ` Marco Elver
2020-02-03 16:05 ` David Laight
2020-02-03 17:25 ` Paul E. McKenney
2020-02-03 15:58 ` Paul E. McKenney
2020-02-03 16:02 ` Will Deacon
2020-02-03 17:29 ` Paul E. McKenney
2020-02-03 18:27 ` Will Deacon
2020-02-03 21:16 ` Paul E. McKenney
2020-01-31 19:20 ` Marco Elver
2020-01-31 18:52 ` Paul E. McKenney
2020-01-31 18:55 ` Eric Dumazet
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