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Date:   Tue, 31 Mar 2020 00:46:28 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     linux-fsdevel@vger.kernel.org,
        Christoph Hellwig <hch@infradead.org>
Subject: Re: [RFC] iomap: Remove indirect function call
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On Sat, Mar 28, 2020 at 08:51:56AM -0700, Matthew Wilcox wrote:
> By splitting iomap_apply into __iomap_apply and an inline iomap_apply,
> we convert the call to 'actor' into a direct function call.  I haven't
> done any performance measurements, but given the current costs of indirect
> function calls, this would seem worthwhile to me?

Hmm.  Given that emount of compiler stupidity we are dealing with did
you at least look at the assembly output to see if this actually removes
the indirect call?  I wouldn't be quite sure.