Re: [PATCH v1] load_cache_entries_threaded: remove unused src_offset parameter

From: Jeff King <peff@peff.net>
Date: Oct 23, 2018, 20:07 UTC
Message-ID: <20181023200730.GB15214@sigill.intra.peff.net>
In-Reply-To: <7a359876-7d36-5d01-5f47-76ef316b6386@gmail.com>

On Tue, Oct 23, 2018 at 03:13:06PM -0400, Ben Peart wrote:

Show 7 quoted lines

> At one point I also had the additional #ifndef NO_PTHREADS lines but it was
> starting to get messy with the threaded vs non-threaded code paths so I
> removed them.  I'm fine with which ever people find more readable.
> 
> It does make me wonder if there are still platforms taking new build of git
> that don't support threads.  Do we still need to write/test/debug/read
> through the single threaded code paths?

I think the classic offenders here were old Unix systems like AIX, etc.

I've no idea what the current state is on those platforms. I would love it if we could drop NO_PTHREADS. There's a lot of gnarly code there, and I strongly suspect a lot of bugs lurk in the non-threaded halves (e.g., especially around bits like "struct async" which is "maybe a thread, and maybe a fork" depending on your system, which introduces all kinds of subtle process-state dependencies).

But I'm not really sure how to find out aside from adding a deprecation warning and seeing if anybody screams.

See also this RFC from Duy, which might at least make the code itself a little easier to follow:

	https://public-inbox.org/git/20181018180522.17642-1-pclouds@gmail.com/

-Peff