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Date:   Mon, 11 Sep 2023 14:04:39 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Chuck Lever III <chuck.lever@oracle.com>
Cc:     Chuck Lever <cel@kernel.org>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        Neil Brown <neilb@suse.de>,
        Liam Howlett <liam.howlett@oracle.com>,
        Kees Cook <keescook@chromium.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        David Gow <davidgow@google.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v1 11/17] lib: add light-weight queuing mechanism.
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On Mon, 11 Sep 2023 20:30:40 +0000 Chuck Lever III <chuck.lever@oracle.com> wrote:

> 
> 
> > On Sep 11, 2023, at 2:13 PM, Andrew Morton <akpm@linux-foundation.org> wrote:
> > 
> > On Mon, 11 Sep 2023 10:39:43 -0400 Chuck Lever <cel@kernel.org> wrote:
> > 
> >> lwq is a FIFO single-linked queue that only requires a spinlock
> >> for dequeueing, which happens in process context.  Enqueueing is atomic
> >> with no spinlock and can happen in any context.
> > 
> > What is the advantage of this over using one of the library
> > facilities which we already have?
> 
> I'll let the patch author respond to that question, but let me pose
> one of my own: What pre-existing facilities are you thinking of, so
> that I may have a look?

Well, I assume that plain old list_heads could be recruited for this
requirement.  And I hope that a FIFO could be implemented using kfifo ;)