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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 08695C76188 for ; Mon, 22 Jul 2019 15:25:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C524E2084D for ; Mon, 22 Jul 2019 15:25:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="uZ63QAzY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728908AbfGVPZc (ORCPT ); Mon, 22 Jul 2019 11:25:32 -0400 Received: from mail-wm1-f65.google.com ([209.85.128.65]:34938 "EHLO mail-wm1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728474AbfGVPZc (ORCPT ); Mon, 22 Jul 2019 11:25:32 -0400 Received: by mail-wm1-f65.google.com with SMTP id l2so35748598wmg.0; Mon, 22 Jul 2019 08:25:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:subject:to:cc:references:from:openpgp:autocrypt:message-id :date:user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=5LxJJzfj24V008N7ss4UH0jDpnObaJiZ7hC/fVauSAg=; b=uZ63QAzYVQfTNneRvH9kDLJ/zQ+PXO8USXIkCNdegzE0SbafAOJLRD10X7jKRZjGDi iM6DzQ2AoIBEB+Dkyy/tsKc64K2+w2Btjh7bsPiS74ul2EfvxK7URqdX94ZUIJBsovt+ dml4DX2MbnxeQaC422CtdOcp+91uKmkg8Zk/E8p7c6IwA4jp6yOH+GGoZKdoLH7WJLqM 6WOayvLnXj4UiCSm2YWsNRZANrIxzCjxUVLXybSjNAmVGEqSVErUqBsmNTED9Q6B+raq SEXykC54cSvUqg071w+3jvLxEmdh/gWJafmObu6K0MheCxtoWm7bsCCQ/WVAQ9FzsQIl YlEQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:subject:to:cc:references:from:openpgp :autocrypt:message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=5LxJJzfj24V008N7ss4UH0jDpnObaJiZ7hC/fVauSAg=; b=rmLVtoUSe4UkS6xDDjvEEqLzqqGYs8yIlWGq5QHiPXPDimwrzrO84pHPuzEtWnDwkk fjpdvaPaK55Kq9DgHphwmpMlccgNarusi/X6zxzhHkyBMgtt7ukdIPcEvOpnVhet0BXN dKITPHx/+qNvdc7PI1nAOTZ//jJjKlrPa72n74J8M6H9QOTTM2P1uB41fh3OyxJe+Fqd vy+HFph+hzp9JEgVLYvx81iwKHzySTOQ68hAod66r83rQSaVHcsLmcbrK5nVokTOixg+ 8H+kZNZv623p3ApOaEHwwHLOM/UMdnM4rNFxUYWXFo581hNCOfCMmQ0YeIIfs0Khm9sK RTfw== X-Gm-Message-State: APjAAAXij3s4XXnzbwD3Jgm+ROWZu08nSBPGJFI1flyufaeY2JJVc9/3 m8LCiPZhycDA3EjZI4uvHd6XIhvNO6g= X-Google-Smtp-Source: APXvYqznDrL/g3afwneK3sqh5a0JODGxxLyOWrIjKpu2ML70wGNL0+OtvkqdVIouf2r76/X579Ajrg== X-Received: by 2002:a1c:e109:: with SMTP id y9mr30260981wmg.35.1563809128539; Mon, 22 Jul 2019 08:25:28 -0700 (PDT) Received: from [192.168.10.150] ([93.56.166.5]) by smtp.googlemail.com with ESMTPSA id x6sm41602104wrt.63.2019.07.22.08.25.27 (version=TLS1_3 cipher=AEAD-AES128-GCM-SHA256 bits=128/128); Mon, 22 Jul 2019 08:25:27 -0700 (PDT) Subject: Re: [patch 0/5] cpuidle haltpoll driver and governor (v6) To: "Rafael J. Wysocki" , Marcelo Tosatti Cc: kvm-devel , Radim Krcmar , Andrea Arcangeli , "Rafael J. Wysocki" , Peter Zijlstra , Wanpeng Li , Konrad Rzeszutek Wilk , Raslan KarimAllah , Boris Ostrovsky , Ankur Arora , Christian Borntraeger , Linux PM References: <20190703235124.783034907@amt.cnet> From: Paolo Bonzini Openpgp: preference=signencrypt Autocrypt: addr=pbonzini@redhat.com; keydata= mQHhBFRCcBIBDqDGsz4K0zZun3jh+U6Z9wNGLKQ0kSFyjN38gMqU1SfP+TUNQepFHb/Gc0E2 CxXPkIBTvYY+ZPkoTh5xF9oS1jqI8iRLzouzF8yXs3QjQIZ2SfuCxSVwlV65jotcjD2FTN04 hVopm9llFijNZpVIOGUTqzM4U55sdsCcZUluWM6x4HSOdw5F5Utxfp1wOjD/v92Lrax0hjiX DResHSt48q+8FrZzY+AUbkUS+Jm34qjswdrgsC5uxeVcLkBgWLmov2kMaMROT0YmFY6A3m1S P/kXmHDXxhe23gKb3dgwxUTpENDBGcfEzrzilWueOeUWiOcWuFOed/C3SyijBx3Av/lbCsHU Vx6pMycNTdzU1BuAroB+Y3mNEuW56Yd44jlInzG2UOwt9XjjdKkJZ1g0P9dwptwLEgTEd3Fo UdhAQyRXGYO8oROiuh+RZ1lXp6AQ4ZjoyH8WLfTLf5g1EKCTc4C1sy1vQSdzIRu3rBIjAvnC tGZADei1IExLqB3uzXKzZ1BZ+Z8hnt2og9hb7H0y8diYfEk2w3R7wEr+Ehk5NQsT2MPI2QBd wEv1/Aj1DgUHZAHzG1QN9S8wNWQ6K9DqHZTBnI1hUlkp22zCSHK/6FwUCuYp1zcAEQEAAbQj UGFvbG8gQm9uemluaSA8cGJvbnppbmlAcmVkaGF0LmNvbT6JAg0EEwECACMFAlRCcBICGwMH CwkIBwMCAQYVCAIJCgsEFgIDAQIeAQIXgAAKCRB+FRAMzTZpsbceDp9IIN6BIA0Ol7MoB15E 11kRz/ewzryFY54tQlMnd4xxfH8MTQ/mm9I482YoSwPMdcWFAKnUX6Yo30tbLiNB8hzaHeRj jx12K+ptqYbg+cevgOtbLAlL9kNgLLcsGqC2829jBCUTVeMSZDrzS97ole/YEez2qFpPnTV0 VrRWClWVfYh+JfzpXmgyhbkuwUxNFk421s4Ajp3d8nPPFUGgBG5HOxzkAm7xb1cjAuJ+oi/K CHfkuN+fLZl/u3E/fw7vvOESApLU5o0icVXeakfSz0LsygEnekDbxPnE5af/9FEkXJD5EoYG SEahaEtgNrR4qsyxyAGYgZlS70vkSSYJ+iT2rrwEiDlo31MzRo6Ba2FfHBSJ7lcYdPT7bbk9 AO3hlNMhNdUhoQv7M5HsnqZ6unvSHOKmReNaS9egAGdRN0/GPDWr9wroyJ65ZNQsHl9nXBqE AukZNr5oJO5vxrYiAuuTSd6UI/xFkjtkzltG3mw5ao2bBpk/V/YuePrJsnPFHG7NhizrxttB nTuOSCMo45pfHQ+XYd5K1+Cv/NzZFNWscm5htJ0HznY+oOsZvHTyGz3v91pn51dkRYN0otqr bQ4tlFFuVjArBZcapSIe6NV8C4cEiSS5AQ0EVEJxcwEIAK+nUrsUz3aP2aBjIrX3a1+C+39R nctpNIPcJjFJ/8WafRiwcEuLjbvJ/4kyM6K7pWUIQftl1P8Woxwb5nqL7zEFHh5I+hKS3haO 5pgco//V0tWBGMKinjqntpd4U4Dl299dMBZ4rRbPvmI8rr63sCENxTnHhTECyHdGFpqSzWzy 97rH68uqMpxbUeggVwYkYihZNd8xt1+lf7GWYNEO/QV8ar/qbRPG6PEfiPPHQd/sldGYavmd //o6TQLSJsvJyJDt7KxulnNT8Q2X/OdEuVQsRT5glLaSAeVAABcLAEnNgmCIGkX7TnQF8a6w gHGrZIR9ZCoKvDxAr7RP6mPeS9sAEQEAAYkDEgQYAQIACQUCVEJxcwIbAgEpCRB+FRAMzTZp scBdIAQZAQIABgUCVEJxcwAKCRC/+9JfeMeug/SlCACl7QjRnwHo/VzENWD9G2VpUOd9eRnS DZGQmPo6Mp3Wy8vL7snGFBfRseT9BevXBSkxvtOnUUV2YbyLmolAODqUGzUI8ViF339poOYN i6Ffek0E19IMQ5+CilqJJ2d5ZvRfaq70LA/Ly9jmIwwX4auvXrWl99/2wCkqnWZI+PAepkcX JRD4KY2fsvRi64/aoQmcxTiyyR7q3/52Sqd4EdMfj0niYJV0Xb9nt8G57Dp9v3Ox5JeWZKXS krFqy1qyEIypIrqcMbtXM7LSmiQ8aJRM4ZHYbvgjChJKR4PsKNQZQlMWGUJO4nVFSkrixc9R Z49uIqQK3b3ENB1QkcdMg9cxsB0Onih8zR+Wp1uDZXnz1ekto+EivLQLqvTjCCwLxxJafwKI bqhQ+hGR9jF34EFur5eWt9jJGloEPVv0GgQflQaE+rRGe+3f5ZDgRe5Y/EJVNhBhKcafcbP8 MzmLRh3UDnYDwaeguYmxuSlMdjFL96YfhRBXs8tUw6SO9jtCgBvoOIBDCxxAJjShY4KIvEpK b2hSNr8KxzelKKlSXMtB1bbHbQxiQcerAipYiChUHq1raFc3V0eOyCXK205rLtknJHhM5pfG 6taABGAMvJgm/MrVILIxvBuERj1FRgcgoXtiBmLEJSb7akcrRlqe3MoPTntSTNvNzAJmfWhd SvP0G1WDLolqvX0OtKMppI91AWVu72f1kolJg43wbaKpRJg1GMkKEI3H+jrrlTBrNl/8e20m TElPRDKzPiowmXeZqFSS1A6Azv0TJoo9as+lWF+P4zCXt40+Zhh5hdHO38EV7vFAVG3iuay6 7ToF8Uy7tgc3mdH98WQSmHcn/H5PFYk3xTP3KHB7b0FZPdFPQXBZb9+tJeZBi9gMqcjMch+Y R8dmTcQRQX14bm5nXlBF7VpSOPZMR392LY7wzAvRdhz7aeIUkdO7VelaspFk2nT7wOj1Y6uL nRxQlLkBDQRUQnHuAQgAx4dxXO6/Zun0eVYOnr5GRl76+2UrAAemVv9Yfn2PbDIbxXqLff7o yVJIkw4WdhQIIvvtu5zH24iYjmdfbg8iWpP7NqxUQRUZJEWbx2CRwkMHtOmzQiQ2tSLjKh/c HeyFH68xjeLcinR7jXMrHQK+UCEw6jqi1oeZzGvfmxarUmS0uRuffAb589AJW50kkQK9VD/9 QC2FJISSUDnRC0PawGSZDXhmvITJMdD4TjYrePYhSY4uuIV02v028TVAaYbIhxvDY0hUQE4r 8ZbGRLn52bEzaIPgl1p/adKfeOUeMReg/CkyzQpmyB1TSk8lDMxQzCYHXAzwnGi8WU9iuE1P 0wARAQABiQHzBBgBAgAJBQJUQnHuAhsMAAoJEH4VEAzNNmmxp1EOoJy0uZggJm7gZKeJ7iUp eX4eqUtqelUw6gU2daz2hE/jsxsTbC/w5piHmk1H1VWDKEM4bQBTuiJ0bfo55SWsUNN+c9hh IX+Y8LEe22izK3w7mRpvGcg+/ZRG4DEMHLP6JVsv5GMpoYwYOmHnplOzCXHvmdlW0i6SrMsB Dl9rw4AtIa6bRwWLim1lQ6EM3PWifPrWSUPrPcw4OLSwFk0CPqC4HYv/7ZnASVkR5EERFF3+ 6iaaVi5OgBd81F1TCvCX2BEyIDRZLJNvX3TOd5FEN+lIrl26xecz876SvcOb5SL5SKg9/rCB ufdPSjojkGFWGziHiFaYhbuI2E+NfWLJtd+ZvWAAV+O0d8vFFSvriy9enJ8kxJwhC0ECbSKF Y+W1eTIhMD3aeAKY90drozWEyHhENf4l/V+Ja5vOnW+gCDQkGt2Y1lJAPPSIqZKvHzGShdh8 DduC0U3xYkfbGAUvbxeepjgzp0uEnBXfPTy09JGpgWbg0w91GyfT/ujKaGd4vxG2Ei+MMNDm S1SMx7wu0evvQ5kT9NPzyq8R2GIhVSiAd2jioGuTjX6AZCFv3ToO53DliFMkVTecLptsXaes uUHgL9dKIfvpm+rNXRn9wAwGjk0X/A== Message-ID: <4482d633-553d-d550-920d-822d9df55b3d@redhat.com> Date: Mon, 22 Jul 2019 17:25:28 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On 04/07/19 10:32, Rafael J. Wysocki wrote: > On Thu, Jul 4, 2019 at 1:59 AM Marcelo Tosatti wrote: >> >> (rebased against queue branch of kvm.git tree) >> >> The cpuidle-haltpoll driver with haltpoll governor allows the guest >> vcpus to poll for a specified amount of time before halting. >> This provides the following benefits to host side polling: >> >> 1) The POLL flag is set while polling is performed, which allows >> a remote vCPU to avoid sending an IPI (and the associated >> cost of handling the IPI) when performing a wakeup. >> >> 2) The VM-exit cost can be avoided. >> >> The downside of guest side polling is that polling is performed >> even with other runnable tasks in the host. >> >> Results comparing halt_poll_ns and server/client application >> where a small packet is ping-ponged: >> >> host --> 31.33 >> halt_poll_ns=300000 / no guest busy spin --> 33.40 (93.8%) >> halt_poll_ns=0 / guest_halt_poll_ns=300000 --> 32.73 (95.7%) >> >> For the SAP HANA benchmarks (where idle_spin is a parameter >> of the previous version of the patch, results should be the >> same): >> >> hpns == halt_poll_ns >> >> idle_spin=0/ idle_spin=800/ idle_spin=0/ >> hpns=200000 hpns=0 hpns=800000 >> DeleteC06T03 (100 thread) 1.76 1.71 (-3%) 1.78 (+1%) >> InsertC16T02 (100 thread) 2.14 2.07 (-3%) 2.18 (+1.8%) >> DeleteC00T01 (1 thread) 1.34 1.28 (-4.5%) 1.29 (-3.7%) >> UpdateC00T03 (1 thread) 4.72 4.18 (-12%) 4.53 (-5%) >> >> V2: >> >> - Move from x86 to generic code (Paolo/Christian) >> - Add auto-tuning logic (Paolo) >> - Add MSR to disable host side polling (Paolo) >> >> V3: >> >> - Do not be specific about HLT VM-exit in the documentation (Ankur Arora) >> - Mark tuning parameters static and __read_mostly (Andrea Arcangeli) >> - Add WARN_ON if host does not support poll control (Joao Martins) >> - Use sched_clock and cleanup haltpoll_enter_idle (Peter Zijlstra) >> - Mark certain functions in kvm.c as static (kernel test robot) >> - Remove tracepoints as they use RCU from extended quiescent state (kernel >> test robot) >> >> V4: >> - Use a haltpoll governor, use poll_state.c poll code (Rafael J. Wysocki) >> >> V5: >> - Take latency requirement into consideration (Rafael J. Wysocki) >> - Set target_residency/exit_latency to 1 (Rafael J. Wysocki) >> - Do not load cpuidle driver if not virtualized (Rafael J. Wysocki) >> >> V6: >> - Switch from callback to poll_limit_ns variable in cpuidle device structure >> (Rafael J. Wysocki) >> - Move last_used_idx to cpuidle device structure (Rafael J. Wysocki) >> - Drop per-cpu device structure in haltpoll governor (Rafael J. Wysocki) > > It looks good to me now, but I have some cpuidle changes in the work > that will clash in some changes in this series if not rebased on top > of it, so IMO it would make sense for me to get patches [1-4/5] at > least into my queue. I can expose an immutable branch with them for > the KVM tree to consume. I can take the last patch in the series as > well if I get an ACK for it. > > Would that work for everybody? Rafael, please take the whole series in your tree. Thanks! Paolo