From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gregory Haskins Subject: Re: [GIT PULL] AlacrityVM guest drivers for 2.6.33 Date: Tue, 22 Dec 2009 14:47:30 -0500 Message-ID: <4B312252.4040009@gmail.com> References: <4B1D4F29.8020309@gmail.com> <20091218215107.GA14946@elte.hu> <4B2F9582.5000002@gmail.com> <20091222075742.GB26467@elte.hu> <4B3103B4.4070708@gmail.com> <4B3115C1.4070303@redhat.com> <4B311ADA.4000700@gmail.com> <4B311D20.7020400@redhat.com> <4B311ECB.6040205@gmail.com> <4B312042.7010804@redhat.com> <4B3120E2.7070307@gmail.com> <4B312155.7040308@redhat.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enigE0499CCAC912016D7F3A4A46" Cc: Ingo Molnar , kvm@vger.kernel.org, Andrew Morton , torvalds@linux-foundation.org, "linux-kernel@vger.kernel.org" , netdev@vger.kernel.org, "alacrityvm-devel@lists.sourceforge.net" To: Avi Kivity Return-path: Received: from mail-gx0-f211.google.com ([209.85.217.211]:41365 "EHLO mail-gx0-f211.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754784AbZLVTrf (ORCPT ); Tue, 22 Dec 2009 14:47:35 -0500 In-Reply-To: <4B312155.7040308@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigE0499CCAC912016D7F3A4A46 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 12/22/09 2:43 PM, Avi Kivity wrote: > On 12/22/2009 09:41 PM, Gregory Haskins wrote: >> >>> It means that kvm locking suddenly affects more of the kernel. >>> >>> =20 >> Thats ok. This would only be w.r.t. devices that are bound to the KVM= >> instance anyway, so they better know what they are doing (and they do)= =2E >> >> =20 >=20 > It's okay to the author of that device. It's not okay to the kvm > developers who are still evolving the locking and have to handle all > devices that use xinterface. Perhaps, but like it or not, if you want to do in-kernel you need to invoke backends. And if you want to invoke backends, limiting it to thread wakeups is, well, limiting. For one, you miss out on that exploit I mentioned earlier which can help sometimes. Besides, the direction that Marcelo and I left the mmio/pio bus was that it would go lockless eventually, not "more lockful" ;) Has that changed? I honestly haven't followed whats going on in the io-bus code in a while. -Greg --------------enigE0499CCAC912016D7F3A4A46 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.11 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAksxIlIACgkQP5K2CMvXmqHixgCdEafS1WfHfXOoJ+5gQVBDOnHo YywAn0cPxfpSdKx+ezbd3B9DW7hiqpqu =sloy -----END PGP SIGNATURE----- --------------enigE0499CCAC912016D7F3A4A46--