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Date:   Wed, 13 Oct 2021 17:13:12 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     Christoph Hellwig <hch@infradead.org>, linux-block@vger.kernel.org
Subject: Re: [PATCH 6/9] nvme: add support for batched completion of polled IO
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On Wed, Oct 13, 2021 at 10:04:36AM -0600, Jens Axboe wrote:
> On 10/13/21 9:50 AM, Christoph Hellwig wrote:
> > On Wed, Oct 13, 2021 at 09:42:23AM -0600, Jens Axboe wrote:
> >> Something like this?
> > 
> > Something like that.  Although without making the new function inline
> > this will generate an indirect call.
> 
> It will, but I don't see how we can have it both ways...

Last time I played with these optimization gcc did inline function
pointers passed to __always_inline function into the calling
function.  That is you can keep the source level abstraction but get the
code generation as if it was open coded.