From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B581FC433DB for ; Tue, 2 Feb 2021 15:03:41 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 6BBC364F5C for ; Tue, 2 Feb 2021 15:03:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6BBC364F5C Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.80587.147447 (Exim 4.92) (envelope-from ) id 1l6xD9-0007tL-6A; Tue, 02 Feb 2021 15:03:23 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 80587.147447; Tue, 02 Feb 2021 15:03:23 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1l6xD9-0007tE-3A; Tue, 02 Feb 2021 15:03:23 +0000 Received: by outflank-mailman (input) for mailman id 80587; Tue, 02 Feb 2021 15:03:22 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1l6xD7-0007t9-VN for xen-devel@lists.xenproject.org; Tue, 02 Feb 2021 15:03:21 +0000 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id ff164533-b49f-4ddd-b103-126440e6d3a3; Tue, 02 Feb 2021 15:03:20 +0000 (UTC) Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id EADCBAD57; Tue, 2 Feb 2021 15:03:19 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: ff164533-b49f-4ddd-b103-126440e6d3a3 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1612278200; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=68SE39HbaZaq/EHFcUnvvpfmGpnlieWm24yT1YRTzWg=; b=V/TreyBkVM0RSNZfKFebGXM5zcg4e+90YAsxZhPAeqz2wTwN3WnjsvtTqhSQRLvtMA238A 87OH9tzy+9TOJHU7N3NFVabCpYONOYwD/mL6yKcR0T82LcvI8opL4jTRycZN+qyU7cwrNC DlDQugwT+pbPOTc5nf2Oz3THF2IzPKk= Message-ID: <311bb201bcacfd356f0c0b67856754eceae39e37.camel@suse.com> Subject: Re: Null scheduler and vwfi native problem From: Dario Faggioli To: Julien Grall , Anders =?ISO-8859-1?Q?T=F6rnqvist?= , xen-devel@lists.xenproject.org, Stefano Stabellini Date: Tue, 02 Feb 2021 16:03:18 +0100 In-Reply-To: <4760cbac-b006-78bc-b064-3265384f6707@xen.org> References: <207305e4e2998614767fdcc5ad83ced6de982820.camel@suse.com> <744ddde6-a228-82fc-76b9-401926d7963b@xen.org> <18ef4619-19ae-90d2-459c-9b5282b49176@codiax.se> <4760cbac-b006-78bc-b064-3265384f6707@xen.org> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-R/S8TuxHfJahqHl9r7DO" User-Agent: Evolution 3.38.3 (by Flathub.org) MIME-Version: 1.0 --=-R/S8TuxHfJahqHl9r7DO Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Tue, 2021-02-02 at 07:59 +0000, Julien Grall wrote: > Hi Dario, >=20 Hi! > I have had a quick look at your place. The RCU call in=20 > leave_hypervisor_to_guest() needs to be placed just after the last > call=20 > to check_for_pcpu_work(). >=20 > Otherwise, you may be preempted and keep the RCU quiet. >=20 Ok, makes sense. I'll move it. > The placement in enter_hypervisor_from_guest() doesn't matter too > much,=20 > although I would consider to call it as a late as possible. >=20 Mmmm... Can I ask why? In fact, I would have said "as soon as possible". Thanks and Regards --=20 Dario Faggioli, Ph.D http://about.me/dario.faggioli Virtualization Software Engineer SUSE Labs, SUSE https://www.suse.com/ ------------------------------------------------------------------- <> (Raistlin Majere) --=-R/S8TuxHfJahqHl9r7DO Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEES5ssOj3Vhr0WPnOLFkJ4iaW4c+4FAmAZabYACgkQFkJ4iaW4 c+5FLg/+JZW0aeDvv0sWbH+C7aKYkyA2LGmft0QaEvYE/guNn8AlDt/0cazmDIem N3IxwCsHa2B8hdrBM8s4p/5hTsEggoIS78A7p9VfKqfZloHASwuOtG6bEuPb7ZTN MBH9rjrqOg7l//nEc0rgnsoRi0wTuWIZ3yJp1JthVmtrtAuul+jNryvfvWEHz+jE TBuwbF3t5SYh7CfHFYQzcYgF+DfOKDhY9UzUktZyQFbtDMhhqxMfPklJNcHuA7SQ Eurcx12G0jz/n8MCoJbvcwt/HeFLNE+8qeAz35Am/Zm1hDpJiZ0Zsunr6tyiO06L lKL8wp+4OF7ql0bBvJuHCdtUXxPnOXGJnkBpwBHnkZeuh5Cl7tLJ9Wk7HMyYMMa8 fKRCqGljWBFzneiRRggzlc3ijvJE/UeQKB0Idn73UDeQW9yPnfkJObKC20qKA33h Tg5nOVPz2hkV7/tNJ7u1plC+CTWoaVzTlNoRccjxh8QJjsl4Ln89UzQmmR4tk4ha YkOV3ENChK0K7PJ03cizlmmwkkQc6f0yXdbM9O5rq+qmFEhsA8Ru4U/69GQEsYqm dx65gyAMRbc1ODCHD0NuG/84/8fSS3GIc2PZigKR/t8bYttX9PzA00pvCxIiAl3D XhOiDgwB4xPITVSXR9ozJRXbsopbbz8lD/B3Wvhc/9V10wdcXi4= =IVOe -----END PGP SIGNATURE----- --=-R/S8TuxHfJahqHl9r7DO--