From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dario Faggioli Subject: Re: [PATCH v2 1/7] xen: credit1: simplify csched_runq_steal() a little bit. Date: Fri, 7 Apr 2017 13:00:18 +0200 Message-ID: <1491562818.3287.8.camel@citrix.com> References: <149146456487.21348.8554211499146017782.stgit@Solace.fritz.box> <149146656929.21348.389782940595763501.stgit@Solace.fritz.box> <2befc2c8-b31f-b1a7-8f08-68593ddb2d05@citrix.com> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============8108468635377993103==" Return-path: Received: from mail6.bemta6.messagelabs.com ([193.109.254.103]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cwRd3-0006yh-0v for xen-devel@lists.xenproject.org; Fri, 07 Apr 2017 11:00:33 +0000 In-Reply-To: <2befc2c8-b31f-b1a7-8f08-68593ddb2d05@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" To: George Dunlap , xen-devel@lists.xenproject.org Cc: George Dunlap , Anshul Makkar List-Id: xen-devel@lists.xenproject.org --===============8108468635377993103== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="=-8H925kx1jFcGAZfbDai8" --=-8H925kx1jFcGAZfbDai8 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, 2017-04-07 at 11:45 +0100, George Dunlap wrote: > On 06/04/17 09:16, Dario Faggioli wrote: > > Since we're holding the lock on the pCPU from which we > > are trying to steal, it can't have disappeared, so we > > can drop the check for that (and convert it in an > > ASSERT()). > >=20 > > And since we try to steal only from busy pCPUs, it's > > unlikely for such pCPU to be idle, so we mark it as > > such (and bail early if it unfortunately is). >=20 > Oh, you mean "mark the test as unlikely".=C2=A0=C2=A0I initially parsed t= his > as, > "Mark the pcpu as idle", which confused me. >=20 > Can I change this to, "tell the compiler that it's unlikely"? >=20 Indeed. AFAICS, I'll have to resend, so I will do this myself. > Either way: >=20 > Reviewed-by; George Dunlap >=20 Thanks, Dario --=20 <> (Raistlin Majere) ----------------------------------------------------------------- Dario Faggioli, Ph.D, http://about.me/dario.faggioli Senior Software Engineer, Citrix Systems R&D Ltd., Cambridge (UK) --=-8H925kx1jFcGAZfbDai8 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 v2 iQIcBAABCAAGBQJY53FDAAoJEBZCeImluHPu85EQAIBW0ZM5dqxNohlCE+hQ6M9x EQ7FqeEhvbBrQ0ws+M6hLUbycqlnB45CR1OmROC3hNDpAqbxr6WDRnjCVY2L2IWe NEdvFSRpzsoSg1mQHNFrmxwHyt22uR74l+yfktT15iM9xaHqqkdd+dJn5dnEZlR8 YENe75A6zCmAT0+u10GPjJcPqBni+v4VTRBnqxF3jJFeV/kEnB4afydt1CiQu+xa hkwLRI8b5nKtuXW9p9Ya+KFGpd5WIwdjRmorTdA6MTmhUwNo7d1qun0Yg4d0S4iD Eff6LMVQBrGilkhywLuHPnUk7PKq4mUlvRBjXq+ZRGyxzUuaZKsuqoPRZUKZ2ezt VKaZSS/qDFXHAlpQSjwxD9GxRZqFr1auc0LnE5oAXgdWr5jqJMAjhOehHko2hopA 8F/u2H61SZYqo+Rl/+oNI9TiyBn8AKGY7HxoXpoy7IzpfSnBUiegR25Y7CbnpFYO FKnpOLwzrhBuovuLYIM/fzARWVP6+SjHeEkXBRBs1t5ATmeyT6e1ADKqM4iWr5Qo cuj2uf++86L2OpkBt0jbNaxXRUp99A5jSzoXp+MrPb01QNi3uGPBiXCHz5R5u+Sg bLl09TvqVpvvG6/VXTxn+5Pv2qo3IbrViZ80dkQNI3ZZ8lU1X8LrS4N09t+OcMvh wmJxWPgC26bdVpkuW3/6 =xDGV -----END PGP SIGNATURE----- --=-8H925kx1jFcGAZfbDai8-- --===============8108468635377993103== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KWGVuLWRldmVs IG1haWxpbmcgbGlzdApYZW4tZGV2ZWxAbGlzdHMueGVuLm9yZwpodHRwczovL2xpc3RzLnhlbi5v cmcveGVuLWRldmVsCg== --===============8108468635377993103==--