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Date: Fri, 21 Apr 2023 15:30:17 -0700
From: Luis Chamberlain <mcgrof@kernel.org>
To: Jens Axboe <axboe@kernel.dk>
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Subject: Re: [Drbd-dev] [PATCH 3/5] iomap: simplify iomap_init() with
	PAGE_SECTORS
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On Fri, Apr 21, 2023 at 04:24:57PM -0600, Jens Axboe wrote:
> On 4/21/23 4:02 PM, Luis Chamberlain wrote:
> > On Fri, Apr 21, 2023 at 09:14:00PM +0100, Matthew Wilcox wrote:
> >> On Fri, Apr 21, 2023 at 12:58:05PM -0700, Luis Chamberlain wrote:
> >>> Just use the PAGE_SECTORS generic define. This produces no functional
> >>> changes. While at it use left shift to simplify this even further.
> >>
> >> How is FOO << 2 simpler than FOO * 4?
> >>
> >>> -	return bioset_init(&iomap_ioend_bioset, 4 * (PAGE_SIZE / SECTOR_SIZE),
> >>> +	return bioset_init(&iomap_ioend_bioset, PAGE_SECTORS << 2,
> > 
> > We could just do:
> > 
> > 
> > -	return bioset_init(&iomap_ioend_bioset, 4 * (PAGE_SIZE / SECTOR_SIZE),
> > +	return bioset_init(&iomap_ioend_bioset, 4 * PAGE_SECTORS,
> > 
> > The shift just seemed optimal if we're just going to change it.
> 
> It's going to generate the same code, but the multiplication is arguably
> easier to read (or harder to misread).

Then let's stick with the 4 * PAGE_SECTORS. Let me know if you need another
patch.

  Luis