From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/6522 Path: news.gmane.org!not-for-mail From: Jens Gustedt Newsgroups: gmane.linux.lib.musl.general Subject: Re: ARM atomics overhaul for musl Date: Sun, 16 Nov 2014 23:33:15 +0100 Message-ID: <1416177195.16479.110.camel@eris.loria.fr> References: <20141116055656.GA13940@brightrain.aerifal.cx> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-Cf3SiBlX7sQtFEPeCcDU" X-Trace: ger.gmane.org 1416177227 30164 80.91.229.3 (16 Nov 2014 22:33:47 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sun, 16 Nov 2014 22:33:47 +0000 (UTC) To: musl@lists.openwall.com Original-X-From: musl-return-6535-gllmg-musl=m.gmane.org@lists.openwall.com Sun Nov 16 23:33:42 2014 Return-path: Envelope-to: gllmg-musl@m.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by plane.gmane.org with smtp (Exim 4.69) (envelope-from ) id 1Xq8O5-0001vz-0C for gllmg-musl@m.gmane.org; Sun, 16 Nov 2014 23:33:41 +0100 Original-Received: (qmail 12195 invoked by uid 550); 16 Nov 2014 22:33:39 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: Original-Received: (qmail 12186 invoked from network); 16 Nov 2014 22:33:39 -0000 X-IronPort-AV: E=Sophos;i="5.07,398,1413237600"; d="scan'";a="107429740" In-Reply-To: <20141116055656.GA13940@brightrain.aerifal.cx> Face: 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Cj15cu23XZI4/826Px/xqB37z547sPH374oOvnKTsOb+1zuCoImZARM8ZiLlKkXcWOcoFRJ+Do/CwFO4e2DEe+9Ti+ZXA8ny/cU+X4bMKRZxZIVEiqXI6/+NKuUzPHb7z40ovnX3zx+Ctuq38HyuqWG7Tu+A0AAAAASUVORK5CYII= X-Mailer: Evolution 3.4.4-3 Xref: news.gmane.org gmane.linux.lib.musl.general:6522 Archived-At: --=-Cf3SiBlX7sQtFEPeCcDU Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: quoted-printable Hello, Am Sonntag, den 16.11.2014, 00:56 -0500 schrieb Rich Felker: > One item on the agenda for this release cycle is overhauling the way > atomics are done on ARM. I'm cc'ing people who have been involved in > this discussion in the past in case anyone's not on the musl list and > has opinions about what should be done. >=20 > The current situation looks like the following: ... I don't know enough about the nasty details of this architecture to be helpful, I think. But what I'd very much like to have is some sort of documentation or standards concerning memory ordering for the atomics that we use internally. And also about which OS features are needed/missing to make atomic operations appear stateless (AKA "lockfree" in C11 terminology). Since this is the most complicated architecture (or merely family of architectures) this is probably the best to start such a reflection. Thanks Jens --=20 :: INRIA Nancy Grand Est ::: AlGorille ::: ICube/ICPS ::: :: ::::::::::::::: office Strasbourg : +33 368854536 :: :: :::::::::::::::::::::: gsm France : +33 651400183 :: :: ::::::::::::::: gsm international : +49 15737185122 :: :: http://icube-icps.unistra.fr/index.php/Jens_Gustedt :: --=-Cf3SiBlX7sQtFEPeCcDU Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iEUEABECAAYFAlRpJisACgkQD9PoadrVN+LZxwCfYY/oT37Xr5D7GiB0Gwc/oelT PZQAlRjaPAwvXj8uZaYpdUBu4GlIwtk= =4yyQ -----END PGP SIGNATURE----- --=-Cf3SiBlX7sQtFEPeCcDU--