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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 16 Oct 2019 08:31:48 -0700
Message-ID: <CAHk-=wgMZR8TWpmRBPytGmWJX=C=-bCb5D2PsCx0LUNemAPexA@mail.gmail.com>
Subject: Re: [RFC PATCH 02/21] Add a prelocked wake-up
To:     David Howells <dhowells@redhat.com>
Cc:     Tim Chen <tim.c.chen@linux.intel.com>,
        Kan Liang <kan.liang@intel.com>,
        Casey Schaufler <casey@schaufler-ca.com>,
        Stephen Smalley <sds@tycho.nsa.gov>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Nicolas Dichtel <nicolas.dichtel@6wind.com>, raven@themaw.net,
        Christian Brauner <christian@brauner.io>,
        keyrings@vger.kernel.org, linux-usb@vger.kernel.org,
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On Wed, Oct 16, 2019 at 7:26 AM David Howells <dhowells@redhat.com> wrote:
>
> Btw, is there any point in __wake_up_sync_key() taking a nr_exclusive
> argument since it clears WF_SYNC if nr_exclusive != 1 and doesn't make sense
> to be >1 anyway.

Ack, looks sane to me.

We have _very_ few users of nr_exclusive. I wonder if it's even worth
having at all, but it's definitely not worth it here.

I'd love for nr_exclusive to go away and be replaced by WF_ALL
instead. Right now it looks like there is one SGI driver that uses it,
and the sbitmap code. That was all I could find.

Oh well. You removing one case is at last a small amount of progress.

         Linus