Re: [ANNOUNCE] Git v2.32.0-rc3 - t5300 Still Broken on NonStop ia64/x86

From: Jeff King <peff@peff.net>
To: Eric Wong <e@80x24.org>
Cc: Taylor Blau <me@ttaylorr.com>,
	"Randall S. Becker" <rsbecker@nexbridge.com>,
	'Junio C Hamano' <gitster@pobox.com>,
	git@vger.kernel.org
Subject: Re: [ANNOUNCE] Git v2.32.0-rc3 - t5300 Still Broken on NonStop ia64/x86
Date: Wed, 2 Jun 2021 16:14:27 -0400	[thread overview]
Message-ID: <YLfmo8kl0URnGgp5@coredump.intra.peff.net> (raw)
In-Reply-To: <20210602201150.GA29388@dcvr>

On Wed, Jun 02, 2021 at 08:11:50PM +0000, Eric Wong wrote:

> Jeff King <peff@peff.net> wrote:
> > And so when he gets this error:
> > 
> >   fatal: fsync error on '.git/objects/pack/tmp_pack_NkPgqN': Interrupted system call
> > 
> > presumably we were in fsync() when the signal arrived, and unlike most
> > other platforms, the call needs to be restarted manually (even though we
> > set up the signal with SA_RESTART). I'm not sure if this violates POSIX
> > or not (I couldn't find a definitive answer to the set of interruptible
> > functions in the standard). But either way, the workaround is probably
> > something like:
> 
> "man 3posix fsync" says EINTR is allowed ("manpages-posix-dev"
> package in Debian non-free).

Ah, thanks. Linux's fsync(3) doesn't mention it, and nor does it appear
in the discussion of interruptible calls in signals(7). So I was looking
for a POSIX equivalent of that signals manpage but couldn't find one. :)

> >   #ifdef FSYNC_NEEDS_RESTART
> 
> The wrapper should apply to all platforms.  NFS (and presumably
> other network FSes) can be mounted with interrupts enabled.

I don't mind that, as the wrapper is pretty low-cost (and one less
Makefile knob is nice). If it's widespread, though, I find it curious
that nobody has run into it before now.

-Peff