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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 1E9B7C43387 for ; Wed, 16 Jan 2019 07:50:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DA3FD2082F for ; Wed, 16 Jan 2019 07:50:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728812AbfAPHuR (ORCPT ); Wed, 16 Jan 2019 02:50:17 -0500 Received: from mx2.suse.de ([195.135.220.15]:48638 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727667AbfAPHuR (ORCPT ); Wed, 16 Jan 2019 02:50:17 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 10E3EAFA0; Wed, 16 Jan 2019 07:50:15 +0000 (UTC) Subject: Re: [PATCH v3] xen: Fix x86 sched_clock() interface for xen To: Hans van Kranenburg , linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, x86@kernel.org Cc: boris.ostrovsky@oracle.com, sstabellini@kernel.org, hpa@zytor.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, stable@vger.kernel.org References: <20190114124413.3742-1-jgross@suse.com> From: Juergen Gross Openpgp: preference=signencrypt Autocrypt: addr=jgross@suse.com; prefer-encrypt=mutual; keydata= xsBNBFOMcBYBCACgGjqjoGvbEouQZw/ToiBg9W98AlM2QHV+iNHsEs7kxWhKMjrioyspZKOB ycWxw3ie3j9uvg9EOB3aN4xiTv4qbnGiTr3oJhkB1gsb6ToJQZ8uxGq2kaV2KL9650I1SJve dYm8Of8Zd621lSmoKOwlNClALZNew72NjJLEzTalU1OdT7/i1TXkH09XSSI8mEQ/ouNcMvIJ NwQpd369y9bfIhWUiVXEK7MlRgUG6MvIj6Y3Am/BBLUVbDa4+gmzDC9ezlZkTZG2t14zWPvx XP3FAp2pkW0xqG7/377qptDmrk42GlSKN4z76ELnLxussxc7I2hx18NUcbP8+uty4bMxABEB AAHNHkp1ZXJnZW4gR3Jvc3MgPGpncm9zc0BzdXNlLmRlPsLAeQQTAQIAIwUCU4xw6wIbAwcL CQgHAwIBBhUIAgkKCwQWAgMBAh4BAheAAAoJELDendYovxMvi4UH/Ri+OXlObzqMANruTd4N zmVBAZgx1VW6jLc8JZjQuJPSsd/a+bNr3BZeLV6lu4Pf1Yl2Log129EX1KWYiFFvPbIiq5M5 kOXTO8Eas4CaScCvAZ9jCMQCgK3pFqYgirwTgfwnPtxFxO/F3ZcS8jovza5khkSKL9JGq8Nk czDTruQ/oy0WUHdUr9uwEfiD9yPFOGqp4S6cISuzBMvaAiC5YGdUGXuPZKXLpnGSjkZswUzY d9BVSitRL5ldsQCg6GhDoEAeIhUC4SQnT9SOWkoDOSFRXZ+7+WIBGLiWMd+yKDdRG5RyP/8f 3tgGiB6cyuYfPDRGsELGjUaTUq3H2xZgIPfOwE0EU4xwFgEIAMsx+gDjgzAY4H1hPVXgoLK8 B93sTQFN9oC6tsb46VpxyLPfJ3T1A6Z6MVkLoCejKTJ3K9MUsBZhxIJ0hIyvzwI6aYJsnOew cCiCN7FeKJ/oA1RSUemPGUcIJwQuZlTOiY0OcQ5PFkV5YxMUX1F/aTYXROXgTmSaw0aC1Jpo w7Ss1mg4SIP/tR88/d1+HwkJDVW1RSxC1PWzGizwRv8eauImGdpNnseneO2BNWRXTJumAWDD pYxpGSsGHXuZXTPZqOOZpsHtInFyi5KRHSFyk2Xigzvh3b9WqhbgHHHE4PUVw0I5sIQt8hJq 5nH5dPqz4ITtCL9zjiJsExHuHKN3NZsAEQEAAcLAXwQYAQIACQUCU4xwFgIbDAAKCRCw3p3W KL8TL0P4B/9YWver5uD/y/m0KScK2f3Z3mXJhME23vGBbMNlfwbr+meDMrJZ950CuWWnQ+d+ Ahe0w1X7e3wuLVODzjcReQ/v7b4JD3wwHxe+88tgB9byc0NXzlPJWBaWV01yB2/uefVKryAf AHYEd0gCRhx7eESgNBe3+YqWAQawunMlycsqKa09dBDL1PFRosF708ic9346GLHRc6Vj5SRA UTHnQqLetIOXZm3a2eQ1gpQK9MmruO86Vo93p39bS1mqnLLspVrL4rhoyhsOyh0Hd28QCzpJ wKeHTd0MAWAirmewHXWPco8p1Wg+V+5xfZzuQY0f4tQxvOpXpt4gQ1817GQ5/Ed/wsDtBBgB CAAgFiEEhRJncuj2BJSl0Jf3sN6d1ii/Ey8FAlrd8NACGwIAgQkQsN6d1ii/Ey92IAQZFggA HRYhBFMtsHpB9jjzHji4HoBcYbtP2GO+BQJa3fDQAAoJEIBcYbtP2GO+TYsA/30H/0V6cr/W V+J/FCayg6uNtm3MJLo4rE+o4sdpjjsGAQCooqffpgA+luTT13YZNV62hAnCLKXH9n3+ZAgJ RtAyDWk1B/0SMDVs1wxufMkKC3Q/1D3BYIvBlrTVKdBYXPxngcRoqV2J77lscEvkLNUGsu/z W2pf7+P3mWWlrPMJdlbax00vevyBeqtqNKjHstHatgMZ2W0CFC4hJ3YEetuRBURYPiGzuJXU pAd7a7BdsqWC4o+GTm5tnGrCyD+4gfDSpkOT53S/GNO07YkPkm/8J4OBoFfgSaCnQ1izwgJQ jIpcG2fPCI2/hxf2oqXPYbKr1v4Z1wthmoyUgGN0LPTIm+B5vdY82wI5qe9uN6UOGyTH2B3p hRQUWqCwu2sqkI3LLbTdrnyDZaixT2T0f4tyF5Lfs+Ha8xVMhIyzNb1byDI5FKCb Message-ID: <4808225b-e413-2ec1-77a1-15999c18583f@suse.com> Date: Wed, 16 Jan 2019 08:50:13 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.3.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: de-DE Content-Transfer-Encoding: 7bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On 16/01/2019 01:24, Hans van Kranenburg wrote: > Hi, > > On 1/14/19 1:44 PM, Juergen Gross wrote: >> Commit f94c8d11699759 ("sched/clock, x86/tsc: Rework the x86 'unstable' >> sched_clock() interface") broke Xen guest time handling across >> migration: >> >> [ 187.249951] Freezing user space processes ... (elapsed 0.001 seconds) done. >> [ 187.251137] OOM killer disabled. >> [ 187.251137] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done. >> [ 187.252299] suspending xenstore... >> [ 187.266987] xen:grant_table: Grant tables using version 1 layout >> [18446743811.706476] OOM killer enabled. >> [18446743811.706478] Restarting tasks ... done. >> [18446743811.720505] Setting capacity to 16777216 >> >> Fix that by setting xen_sched_clock_offset at resume time to ensure a >> monotonic clock value. >> >> [...] > > With v3 of the patch, I see the time jump in one log line happen, but > only when using PVH. > > [ 49.486453] Freezing user space processes ... (elapsed 0.002 seconds) > done. > [ 49.488743] OOM killer disabled. > [ 49.488764] Freezing remaining freezable tasks ... (elapsed 0.001 > seconds) done. > [ 49.491117] suspending xenstore... > [2000731.388722] xen:events: Xen HVM callback vector for event delivery > is enabled > [ 49.491750] xen:grant_table: Grant tables using version 1 layout > [ 49.810722] OOM killer enabled. > [ 49.810744] Restarting tasks ... done. > [ 49.856263] Setting capacity to 6291456 > [ 50.006002] Setting capacity to 10485760 > > If I start as PV, it never seems to happen. > > Up to you to decide how important this is. :) We could do something like below. Boris? Juergen --- diff --git a/arch/x86/xen/suspend_hvm.c b/arch/x86/xen/suspend_hvm.c index e666b614cf6d..088f3a6b4be9 100644 --- a/arch/x86/xen/suspend_hvm.c +++ b/arch/x86/xen/suspend_hvm.c @@ -13,6 +13,6 @@ void xen_hvm_post_suspend(int suspend_cancelled) xen_hvm_init_shared_info(); xen_vcpu_restore(); } - xen_callback_vector(); + xen_callback_vector(true); xen_unplug_emulated_devices(); } diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index 0e60bd918695..ba293fda3265 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -55,7 +55,7 @@ void xen_enable_sysenter(void); void xen_enable_syscall(void); void xen_vcpu_restore(void); -void xen_callback_vector(void); +void xen_callback_vector(bool silent); void xen_hvm_init_shared_info(void); void xen_unplug_emulated_devices(void); diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c index 93194f3e7540..8d8d50bea215 100644 --- a/drivers/xen/events/events_base.c +++ b/drivers/xen/events/events_base.c @@ -1637,7 +1637,7 @@ EXPORT_SYMBOL_GPL(xen_set_callback_via); /* Vector callbacks are better than PCI interrupts to receive event * channel notifications because we can receive vector callbacks on any * vcpu and we don't need PCI support or APIC interactions. */ -void xen_callback_vector(void) +void xen_callback_vector(bool silent) { int rc; uint64_t callback_via; @@ -1650,13 +1650,14 @@ void xen_callback_vector(void) xen_have_vector_callback = 0; return; } - pr_info("Xen HVM callback vector for event delivery is enabled\n"); + if (!silent) + pr_info("Xen HVM callback vector for event delivery is enabled\n"); alloc_intr_gate(HYPERVISOR_CALLBACK_VECTOR, xen_hvm_callback_vector); } } #else -void xen_callback_vector(void) {} +void xen_callback_vector(bool silent) {} #endif #undef MODULE_PARAM_PREFIX @@ -1692,7 +1693,7 @@ void __init xen_init_IRQ(void) pci_xen_initial_domain(); } if (xen_feature(XENFEAT_hvm_callback_vector)) - xen_callback_vector(); + xen_callback_vector(false); if (xen_hvm_domain()) { native_init_IRQ();