{"id":805743,"url":"http://patchwork.ozlabs.org/api/patches/805743/?format=json","web_url":"http://patchwork.ozlabs.org/project/linuxppc-dev/patch/20170825043036.18236-4-npiggin@gmail.com/","project":{"id":2,"url":"http://patchwork.ozlabs.org/api/projects/2/?format=json","name":"Linux PPC development","link_name":"linuxppc-dev","list_id":"linuxppc-dev.lists.ozlabs.org","list_email":"linuxppc-dev@lists.ozlabs.org","web_url":"https://github.com/linuxppc/wiki/wiki","scm_url":"https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git","webscm_url":"https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/","list_archive_url":"https://lore.kernel.org/linuxppc-dev/","list_archive_url_format":"https://lore.kernel.org/linuxppc-dev/{}/","commit_url_format":"https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git/commit/?id={}"},"msgid":"<20170825043036.18236-4-npiggin@gmail.com>","list_archive_url":"https://lore.kernel.org/linuxppc-dev/20170825043036.18236-4-npiggin@gmail.com/","date":"2017-08-25T04:30:35","name":"[v3,3/4] powerpc/64s: idle POWER9 can execute stop in virtual mode","commit_ref":"72b0d51d973beab5a06c97279b61a0a58ccf33c8","pull_url":null,"state":"accepted","archived":false,"hash":"a13693c65e7dd8bd51aada629c8a0815ccf55ba4","submitter":{"id":69518,"url":"http://patchwork.ozlabs.org/api/people/69518/?format=json","name":"Nicholas Piggin","email":"npiggin@gmail.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/linuxppc-dev/patch/20170825043036.18236-4-npiggin@gmail.com/mbox/","series":[],"comments":"http://patchwork.ozlabs.org/api/patches/805743/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/805743/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":["patchwork-incoming@ozlabs.org","linuxppc-dev@lists.ozlabs.org"],"Delivered-To":["patchwork-incoming@ozlabs.org","linuxppc-dev@lists.ozlabs.org"],"Received":["from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3])\n\t(using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3xdpMJ0nVSz9t5h\n\tfor ;\n\tFri, 25 Aug 2017 14:38:36 +1000 (AEST)","from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3])\n\tby lists.ozlabs.org (Postfix) with ESMTP id 3xdpMH6gPQzDqMY\n\tfor ;\n\tFri, 25 Aug 2017 14:38:35 +1000 (AEST)","from mail-pg0-x242.google.com (mail-pg0-x242.google.com\n\t[IPv6:2607:f8b0:400e:c05::242])\n\t(using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128\n\tbits)) (No client certificate requested)\n\tby lists.ozlabs.org (Postfix) with ESMTPS id 3xdpBc5pBfzDrK4\n\tfor ;\n\tFri, 25 Aug 2017 14:31:04 +1000 (AEST)","by mail-pg0-x242.google.com with SMTP id t3so2161998pgt.5\n\tfor ;\n\tThu, 24 Aug 2017 21:31:04 -0700 (PDT)","from roar.au.ibm.com (203-219-56-202.tpgi.com.au. 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This\nsaves a switch to real-mode when going idle.\n\nAcked-by: Gautham R. Shenoy \nSigned-off-by: Nicholas Piggin \n---\n arch/powerpc/kernel/idle_book3s.S | 9 +++++++++\n 1 file changed, 9 insertions(+)","diff":"diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S\nindex 14e97f442167..32d65ee323a0 100644\n--- a/arch/powerpc/kernel/idle_book3s.S\n+++ b/arch/powerpc/kernel/idle_book3s.S\n@@ -195,7 +195,16 @@ pnv_powersave_common:\n \tstd\tr5,_CCR(r1)\n \tstd\tr1,PACAR1(r13)\n \n+BEGIN_FTR_SECTION\n+\t/*\n+\t * POWER9 does not require real mode to stop, and presently does not\n+\t * set hwthread_state for KVM (threads don't share MMU context), so\n+\t * we can remain in virtual mode for this.\n+\t */\n+\tbctr\n+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)\n \t/*\n+\t * POWER8\n \t * Go to real mode to do the nap, as required by the architecture.\n \t * Also, we need to be in real mode before setting hwthread_state,\n \t * because as soon as we do that, another thread can switch\n","prefixes":["v3","3/4"]}