X-Recipient:	archive-cygwin AT delorie DOT com
X-SWARE-Spam-Status:	No, hits=-3.9 required=5.0 tests=AWL,BAYES_00,KHOP_PGP_SIGNED,T_RP_MATCHES_RCVD
X-Spam-Check-By:	sourceware.org
Date:	Fri, 1 Jun 2012 17:08:27 -0500
From:	"Ryan C. Underwood" <nemesis-lists AT icequake DOT net>
To:	cygwin AT cygwin DOT com
Subject:	Re: How to "bisect" Cygwin?
Message-ID:	<20120601220827.GG25227@localhost.localdomain>
Reply-To:	nemesis AT icequake DOT net
References:	<20120531210143 DOT GA11744 AT localhost DOT localdomain> <20120601174610 DOT GD25227 AT localhost DOT localdomain> <20120601181852 DOT GF28506 AT calimero DOT vinschen DOT de> <20120601184041 DOT GE25227 AT localhost DOT localdomain> <20120601185906 DOT GG28506 AT calimero DOT vinschen DOT de> <20120601195107 DOT GF25227 AT localhost DOT localdomain> <4FC9391B DOT 3040104 AT etr-usa DOT com>
MIME-Version:	1.0
In-Reply-To:	<4FC9391B.3040104@etr-usa.com>
User-Agent:	Mutt/1.5.21 (2010-09-15)
X-IsSubscribed:	yes
Mailing-List:	contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id:	<cygwin.cygwin.com>
List-Unsubscribe:	<mailto:cygwin-unsubscribe-archive-cygwin=delorie DOT com AT cygwin DOT com>
List-Subscribe:	<mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive:	<http://sourceware.org/ml/cygwin/>
List-Post:	<mailto:cygwin AT cygwin DOT com>
List-Help:	<mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender:	cygwin-owner AT cygwin DOT com
Mail-Followup-To:	cygwin AT cygwin DOT com
Delivered-To:	mailing list cygwin AT cygwin DOT com

--XRI2XbIfl/05pQwm
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Fri, Jun 01, 2012 at 03:50:19PM -0600, Warren Young wrote:
> >
> >The basic issue is that sem_wait() is being kicked out with EINTR
> >extremely frequently (9 out of 10 times or more),
>=20
> Does the attached program vaguely resemble what your program is
> trying to do?  It does get EINTR, but only because I'm using
> alarm(2) to add a timeout to the sem_wait() call.

Yes.  In fact it is very close but with a significant difference.

My (inherited) program is using setitimer() as a master timer, and I
am not sure that the signals are being masked correctly per thread.
In fact, the code is a real mess, but what I have observed is that
with 1.7.9, the SIGALRM which was set by thread 1 does not interrupt
thread 2's sem_wait() system call, but with 1.7.10, the SIGALRM does
interrupt thread 2 (but without delivering the SIGALRM to thread 2,
apparently?  Need to test some more)

Basically, I was hoping to dig down and find some significant changes
in the way signals and threads interact from the 'working' Cygwin to
the 'non-working', which would convince me that I really need to get
to rewriting this stuff if the current Cygwin is considered to be
proper in that respect.  I also wanted to ensure that a bug had not
crept in to Cygwin that would hammer other people with legacy code.

Thanks,

--=20
Ryan C. Underwood, <nemesis AT icequake DOT net>

--XRI2XbIfl/05pQwm
Content-Type: application/pgp-signature; name="signature.asc"
Content-Description: Digital signature

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.11 (GNU/Linux)

iD8DBQFPyT1bIonHnh+67jkRAhgnAJ9EDjlzK/XgR8AEXnnOFPnUo3h4gACcCPn/
hBXUM+9y6YOeLo4awzPUn4Q=
=jHtq
-----END PGP SIGNATURE-----

--XRI2XbIfl/05pQwm--

- Raw text -