From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:51838) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RAhRw-0001Ph-PV for qemu-devel@nongnu.org; Mon, 03 Oct 2011 08:16:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1RAhRv-0003si-QL for qemu-devel@nongnu.org; Mon, 03 Oct 2011 08:16:48 -0400 Received: from fmmailgate02.web.de ([217.72.192.227]:37284) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1RAhRv-0003sQ-KK for qemu-devel@nongnu.org; Mon, 03 Oct 2011 08:16:47 -0400 Message-ID: <4E89A789.8080302@web.de> Date: Mon, 03 Oct 2011 14:16:09 +0200 From: Jan Kiszka MIME-Version: 1.0 References: <1317640994-16559-1-git-send-email-harsh@linux.vnet.ibm.com> In-Reply-To: <1317640994-16559-1-git-send-email-harsh@linux.vnet.ibm.com> Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig54458CCB0F439F8B008F2EB6" Sender: jan.kiszka@web.de Subject: Re: [Qemu-devel] [PATCH 0/2] Introduce QemuRWLock List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Harsh Prateek Bora Cc: stefanha@gmail.com, qemu-devel@nongnu.org, aneesh.kumar@linux.vnet.ibm.com This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig54458CCB0F439F8B008F2EB6 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: quoted-printable On 2011-10-03 13:23, Harsh Prateek Bora wrote: > SynthFS uses rwlocks, which raise the need of a generic QemuRWLock APIs= =2E > This patchset introduces the same making necessary changes to relevant = code. Is the impact of using a plain mutex measurable with 9pfs? Usually it takes very heavy write sections or highly concurrent read sections to actually make a difference. Looking at the cited code, I would dare to rule out the former (even more if the malloc was moved out of the critical section). But I cannot assess the latter. If it does matter, I would vote for introducing RCU directly. Jan --------------enig54458CCB0F439F8B008F2EB6 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.16 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk6Jp40ACgkQitSsb3rl5xSAvQCfazSKkJJuiFGtXlTOPWI+hZAD KTwAoOLtFdpyl8TTElYhxJec7NQoYPmI =mrpV -----END PGP SIGNATURE----- --------------enig54458CCB0F439F8B008F2EB6--