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Date:   Mon, 3 Feb 2020 06:20:50 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     mingo@kernel.org, will@kernel.org, oleg@redhat.com,
        tglx@linutronix.de, linux-kernel@vger.kernel.org,
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        jack@suse.com
Subject: Re: [PATCH -v2 5/7] locking/percpu-rwsem: Remove the embedded rwsem
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On Fri, Jan 31, 2020 at 04:07:08PM +0100, Peter Zijlstra wrote:
> @@ -53,12 +53,6 @@ struct rw_semaphore {
>  #endif
>  };
>  
> -/*
> - * Setting all bits of the owner field except bit 0 will indicate
> - * that the rwsem is writer-owned with an unknown owner.
> - */
> -#define RWSEM_OWNER_UNKNOWN	(-2L)

Can you split the removal of the non-owned resem support into a separate
patch?  I still think keeping this one and moving aio to that scheme is
a better idea than the current ad-hoc locking scheme that has all kinds
of issues.