Date:   Sun, 22 Jan 2023 14:46:48 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Waiman Long <longman@redhat.com>
Cc:     Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>,
        Boqun Feng <boqun.feng@gmail.com>,
        linux-kernel@vger.kernel.org, john.p.donnelly@oracle.com,
        Hillf Danton <hdanton@sina.com>,
        Mukesh Ojha <quic_mojha@quicinc.com>,
        Ting11 Wang =?utf-8?B?546L5am3?= <wangting11@xiaomi.com>
Subject: Re: [PATCH v6 0/6] lockinig/rwsem: Fix rwsem bugs & enable true lock
 handoff
Message-ID: <Y80+SLxrdEVyJHMo@hirez.programming.kicks-ass.net>
References: <20221118022016.462070-1-longman@redhat.com>
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On Thu, Nov 17, 2022 at 09:20:10PM -0500, Waiman Long wrote:

> Waiman Long (6):
>   locking/rwsem: Prevent non-first waiter from spinning in down_write() slowpath
>   locking/rwsem: Disable preemption at all down_read*() and up_read() code paths
>   locking/rwsem: Disable preemption at all down_write*() and up_write() code paths
>   locking/rwsem: Change waiter->hanodff_set to a handoff_state enum

After all these we still have down_read_non_owner() using
__rwsem_set_reader_owner() outside of the preempt_disable() region.

Now, let me go stare at this one:

>   locking/rwsem: Enable direct rwsem lock handoff