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=-5.8 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 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 B48CEC47087 for ; Fri, 28 May 2021 17:03:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 956FC613EB for ; Fri, 28 May 2021 17:03:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236930AbhE1RFd (ORCPT ); Fri, 28 May 2021 13:05:33 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:35232 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231219AbhE1RFb (ORCPT ); Fri, 28 May 2021 13:05:31 -0400 Received: from imap.suse.de (imap-alt.suse-dmz.suse.de [192.168.254.47]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id CC6D8218F5; Fri, 28 May 2021 17:03:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1622221435; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=75k4PzEdZ0gZHKGAzYY0eGe+iK3UwaMHqUnwkJx5A5o=; b=p0ARH8HnTCoDZKNlR2G8JzDiltgNQ/38DRIGApzt/122CNNJNpWqcoGWZi1g1C3ACls/K9 mQf6RAtU2WwGlxS9eHqbdqQd2eVUoYCUQ70TJXWai5Md2YokoeqwyTocI8XN0MN1wSRirW 6t3OmjUrMnrz2YHNl7yl7CP1MWqsb1g= Received: from imap3-int (imap-alt.suse-dmz.suse.de [192.168.254.47]) by imap.suse.de (Postfix) with ESMTP id 5F710118DD; Fri, 28 May 2021 17:03:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1622221434; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=75k4PzEdZ0gZHKGAzYY0eGe+iK3UwaMHqUnwkJx5A5o=; b=QsMY2SGmsOXIGTUj4XR6QkJj2BSObFNlA3M1MbphGYha+o+o/Xs3RteuhtyWmcynM6nsz7 fSrgvW4/blvMCtwp4rgioNT5kxlMWX5QHLyMIbiQPeOj1nrSqNJ7Ql66wy52inepVB1Xqs KfFmSt2XMM7ZAq5rNjtI3XlYJDuVMJk= Received: from director2.suse.de ([192.168.254.72]) by imap3-int with ESMTPSA id 8FxJFHoisWDcQgAALh3uQQ (envelope-from ); Fri, 28 May 2021 17:03:54 +0000 Message-ID: <9e9a9aeefd288c70bdf493601f99820e10dd9eea.camel@suse.com> Subject: Re: [PATCH] Move VMEnter and VMExit tracepoints closer to the actual event From: Dario Faggioli To: Sean Christopherson Cc: Stefano De Venuto , linux-kernel@vger.kernel.org, pbonzini@redhat.com, vkuznets@redhat.com, wanpengli@tencent.com, jmattson@google.com, x86@kernel.org, hpa@zytor.com, kvm@vger.kernel.org, rostedt@goodmis.org, y.karadz@gmail.com Date: Fri, 28 May 2021 19:03:53 +0200 In-Reply-To: References: <20210519182303.2790-1-stefano.devenuto99@gmail.com> <5e6ad92a72e139877fa0e7a1d77682a075060d16.camel@suse.com> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-lih3obsWUBZETTFOvlzL" User-Agent: Evolution 3.40.1 (by Flathub.org) MIME-Version: 1.0 Authentication-Results: imap.suse.de; none X-Spamd-Result: default: False [-0.60 / 100.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; TAGGED_RCPT(0.00)[]; MIME_GOOD(-0.20)[multipart/signed,text/plain]; DKIM_SIGNED(0.00)[suse.com:s=susede1]; RCPT_COUNT_TWELVE(0.00)[12]; SIGNED_PGP(-2.00)[]; RCVD_NO_TLS_LAST(0.10)[]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+,1:+,2:~]; RCVD_COUNT_TWO(0.00)[2]; MID_RHS_MATCH_FROM(0.00)[]; SUSPICIOUS_RECIPS(1.50)[]; FREEMAIL_CC(0.00)[gmail.com,vger.kernel.org,redhat.com,tencent.com,google.com,kernel.org,zytor.com,goodmis.org] Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-lih3obsWUBZETTFOvlzL Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Tue, 2021-05-25 at 16:20 +0000, Sean Christopherson wrote: > On Fri, May 21, 2021, Dario Faggioli wrote: > > >=20 > > Indeed. So, do you happen to have in mind what could be the best > > place > > and the best way for documenting this? >=20 > I didn't have anything in mind, but my gut reaction is to add a new > file dedicated > to tracing/tracepoints in KVM, e.g.=20 >=20 > =C2=A0 Documentation/virt/kvm/tracepoints.rst or > Documentation/virt/kvm/tracing.rst >=20 Ok. Well, FWIW, this seems a good idea to me. :-) > I'm sure there are all sorts of tips and tricks people have for using > KVM's > tracepoints, it would be nice to provide a way to capture and > disseminate them. > My only hesitation is that Documentation/virt/kvm/ might be too > formal for what > would effectively be a wiki of sorts. >=20 Yeah, understand the concerns, I think. However, it seems to me that how to interpret the kernel KVM tracepoint (i.e., this fact that they mark the rather the beginning of the "logical" entry and exit sequences rather than the actual instructions) does belong in the kernel's own documentation, i.e., where you proposed above. Surely when we'll have something like that, it seems natural that we'd want to have more stuff there, and we'll have to judge what's best suited for it and what should perhaps be somewhere else... But I think it's worth a try, and I probably will try to put something together. 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) --=-lih3obsWUBZETTFOvlzL 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+4FAmCxInkACgkQFkJ4iaW4 c+4RdQ/+Nq2BF+hDkOT90KQ7ZGukQK1799sigxVBv6WpqyxNDVRUM5QuKoq6fzqn qLjYGJxH2gkl2lK6EajdD0caG/UM2aUQqnnDtHLY5Bizank6Yc/nv00/PDpqewne M6zhtnm/ymF3fCAc9rIU+lTr2h1dmrcS8qORzLs6506xu7EQNeHTzH1yO3Zi7ZDZ BlzE6c94nBccFpq/kSbXITc0IdSSRvNPjTaaNZttK5do+pD9vBhRpOvmKZPYhFoT z7CfQtByWrLp8KXVG5l6P2Wbn0gdigkbjpOAbgh/FwomScRn6YUitWAvy5feb7/E N5YbSPH4ELgg63bFb4Q7YoBLQDYLtY9Sqt1RCE0qOMi5nf7b5on9tiKLd1Y1RHzN bETtOBpUvG4mCVKpSKsAl20dx4eI+EzgFRdltN12RQJhCj68TV/1NAdC2yyRx5Q+ A8uLSewkbE7ErsIrqPG4QsKo7frFhOMUJScjVXXlhZaYSlQkzytUixVUsYF6d5MX uOerne26fXdwfuGMfQ8C98qWTB7bT11l967QbbiBBte72umC1yQR4SY5b3slJlID 79NY/17Zb1Bwrb/5T10tlDzYBYbN2HBVNrc4jQ2YjmVzcEXgXaKeB8Dal+KulJ+e WRzsb6cgvSEtBYFNangOo6ru/uHpQJyMUAtFGFRjtpA5EWVKI+M= =Kvo0 -----END PGP SIGNATURE----- --=-lih3obsWUBZETTFOvlzL--