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Date: Tue, 7 Jan 2025 22:26:56 +0000
From: Eric Wong <e@80x24.org>
To: Alyssa Ross <hi@alyssa.is>
Cc: meta@public-inbox.org
Subject: Re: [PATCH 2/2] treewide: lose F_SETPIPE_SZ page size assumptions
Message-ID: <20250107222656.M989952@dcvr>
References: <20250107174624.1504268-1-hi@alyssa.is>
 <20250107174624.1504268-3-hi@alyssa.is>
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Alyssa Ross <hi@alyssa.is> wrote:
> fcntl(2) is documented as rounding up sizes to an integer multiple of
> the page size.  When a pipe buffer as small as possible is desired,
> it's cleaner to pass 0 and let the kernel set the pipe buffer to
> exactly one page than it is to assume that pages are 4096 bytes.

OK.  I suppose the Linux kernel has enough testers that it's
chances of it mishandling someday 0 would be caught before any
release.

> Currently, Linux doesn't support pages smaller than 4096 bytes, so this 
> is a purely stylistic change, but I think it will help avoid future 
> bugs caused by assuming page sizes are 4096 bytes.

I'm not 100% convinced it's worth the noise since I expect page
sizes to move towards larger sizes in future arches.  However, I
don't think it conflicts with anything that's being worked on
atm; so leaning towards applying...  Will think about it.