Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756792AbYKKOE3 (ORCPT ); Tue, 11 Nov 2008 09:04:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756078AbYKKOED (ORCPT ); Tue, 11 Nov 2008 09:04:03 -0500 Received: from hs-out-0708.google.com ([64.233.178.247]:6864 "EHLO hs-out-0708.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756024AbYKKOEB (ORCPT ); Tue, 11 Nov 2008 09:04:01 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:x-enigmail-version:openpgp:content-type; b=fs/1mQTxOJhLs82rYtyRLqLAxcugnE+DsycN+ladMb+0ygfJU5OdE/fPKT6pVmICdp MK698LXzLcBDaqeTKLFcaueNsxKxgKTHkQIvw48VgtjKfTDo/nvYfYVRp9D6LIBBw7Zd +97/pHzRtjcfM6vT9K4akNXfek3nJjUmi3qyU= Message-ID: <491991BE.9080405@gmail.com> Date: Tue, 11 Nov 2008 09:07:58 -0500 From: Gregory Haskins User-Agent: Thunderbird 2.0.0.17 (X11/20080922) MIME-Version: 1.0 To: Peter Zijlstra CC: Vaidyanathan Srinivasan , Linux Kernel , Suresh B Siddha , Venkatesh Pallipadi , Ingo Molnar , Dipankar Sarma , Balbir Singh , Vatsa , Gautham R Shenoy , Andi Kleen , David Collier-Brown , Tim Connors , Max Krasnyansky Subject: Re: [RFC PATCH v3 3/5] sched: nominate preferred wakeup cpu References: <20081110181526.562.69941.stgit@drishya.in.ibm.com> <20081110183326.562.37718.stgit@drishya.in.ibm.com> <1226411019.7685.1767.camel@twins> In-Reply-To: <1226411019.7685.1767.camel@twins> X-Enigmail-Version: 0.95.7 OpenPGP: id=CBD79AA1 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig3AA5332198A408DDF351AA4B" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2227 Lines: 62 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig3AA5332198A408DDF351AA4B Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Peter Zijlstra wrote: > On Tue, 2008-11-11 at 00:03 +0530, Vaidyanathan Srinivasan wrote: > =20 >> When the system utilisation is low and more cpus are idle, >> then the process waking up from sleep should prefer to >> wakeup an idle cpu from semi-idle cpu package (multi core >> package) rather than a completely idle cpu package which >> would waste power. >> >> Use the sched_mc balance logic in find_busiest_group() to >> nominate a preferred wakeup cpu. >> >> This info can be sored in appropriate sched_domain, but >> updating this info in all copies of sched_domain is not >> practical. For now lets try with a per-cpu variable >> pointing to a common storage in partition sched domain >> attribute. Global variable may not work in partitioned >> sched domain case. >> =20 > > Would it make sense to place the preferred_wakeup_cpu stuff in the > root_domain structure we already have? > =20 =46rom the description, this is exactly what the root-domains were create= d to solve. Vaidyanathan, just declare your object in "struct root_domain" and initialize it in init_rootdomain() in kernel/sched.c, and then access it via rq->rd to take advantage of this infrastructure. It will automatically follow any partitioning that happens to be configured. -Greg --------------enig3AA5332198A408DDF351AA4B Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iEYEARECAAYFAkkZkb4ACgkQP5K2CMvXmqEmeACgjAcMrXZN1VHXJ6HmK/6+QTg2 llMAn0BsPxua4QNRBJwWCNG6SUEsXAJO =XoPM -----END PGP SIGNATURE----- --------------enig3AA5332198A408DDF351AA4B-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/