From: Peter Zijlstra <peterz@infradead.org>
To: Waiman Long <longman@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>,
linux-kernel@vger.kernel.org, Davidlohr Bueso <dave@stgolabs.net>,
mazhenhua <mazhenhua@xiaomi.com>, Hillf Danton <hdanton@sina.com>,
Maria Yu <quic_aiquny@quicinc.com>
Subject: Re: [PATCH v4] locking/rwsem: Make handoff bit handling more consistent
Date: Tue, 16 Nov 2021 00:07:28 +0100 [thread overview]
Message-ID: <20211115230728.GS174703@worktop.programming.kicks-ass.net> (raw)
In-Reply-To: <ce034084-364b-e30f-cb7c-d6434afe3a7d@redhat.com>
On Mon, Nov 15, 2021 at 05:29:10PM -0500, Waiman Long wrote:
>
> The handoff_set flag can only be true for a first waiter. A random waiter in
> the middle of a wait queue will never has this flag set.
>
> This flag is set in two places in rwsem_try_write_lock():
Bah, I thought it would unconditionally propagate the bit from @count. I
missed the early exit :/
next prev parent reply other threads:[~2021-11-16 1:22 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-12 4:07 [PATCH v4] locking/rwsem: Make handoff bit handling more consistent Waiman Long
2021-11-12 12:10 ` Peter Zijlstra
2021-11-15 3:38 ` Waiman Long
2021-11-15 16:01 ` Peter Zijlstra
2021-11-15 22:29 ` Waiman Long
2021-11-15 23:07 ` Peter Zijlstra [this message]
2021-11-16 0:09 ` Waiman Long
2021-11-15 15:45 ` Aiqun(Maria) Yu
2021-11-15 16:58 ` Waiman Long
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