{"id":816296,"url":"http://patchwork.ozlabs.org/api/patches/816296/?format=json","web_url":"http://patchwork.ozlabs.org/project/ubuntu-kernel/patch/a1088f188488122f9ec549e81cf3af707cb88840.1505244765.git.joseph.salisbury@canonical.com/","project":{"id":15,"url":"http://patchwork.ozlabs.org/api/projects/15/?format=json","name":"Ubuntu Kernel","link_name":"ubuntu-kernel","list_id":"kernel-team.lists.ubuntu.com","list_email":"kernel-team@lists.ubuntu.com","web_url":null,"scm_url":null,"webscm_url":null,"list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"","list_archive_url":null,"date":"2017-09-20T15:17:17","name":"[SRU,Zesty,1/2] powerpc/perf: Avoid spurious PMU interrupts after idle","commit_ref":null,"pull_url":null,"state":"new","archived":false,"hash":"8a1d5907bdbad8ba234620cc75654daba1708493","submitter":{"id":7793,"url":"http://patchwork.ozlabs.org/api/people/7793/?format=json","name":"Joseph Salisbury","email":"joseph.salisbury@canonical.com"},"delegate":null,"mbox":"http://patchwork.ozlabs.org/project/ubuntu-kernel/patch/a1088f188488122f9ec549e81cf3af707cb88840.1505244765.git.joseph.salisbury@canonical.com/mbox/","series":[{"id":4145,"url":"http://patchwork.ozlabs.org/api/series/4145/?format=json","web_url":"http://patchwork.ozlabs.org/project/ubuntu-kernel/list/?series=4145","date":"2017-09-20T15:17:17","name":"Fixes for LP:1716491","version":1,"mbox":"http://patchwork.ozlabs.org/series/4145/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/816296/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/816296/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@bilbo.ozlabs.org","Authentication-Results":"ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=lists.ubuntu.com\n\t(client-ip=91.189.94.19; helo=huckleberry.canonical.com;\n\tenvelope-from=kernel-team-bounces@lists.ubuntu.com;\n\treceiver=)","Received":["from huckleberry.canonical.com (huckleberry.canonical.com\n\t[91.189.94.19])\n\tby ozlabs.org (Postfix) with ESMTP id 3xy3JN6zVyz9t2W;\n\tThu, 21 Sep 2017 01:17:24 +1000 (AEST)","from localhost ([127.0.0.1] helo=huckleberry.canonical.com)\n\tby huckleberry.canonical.com with esmtp (Exim 4.86_2)\n\t(envelope-from )\n\tid 1dugkb-0003fx-7C; Wed, 20 Sep 2017 15:17:21 +0000","from youngberry.canonical.com ([91.189.89.112])\n\tby huckleberry.canonical.com with esmtps\n\t(TLS1.0:DHE_RSA_AES_128_CBC_SHA1:128)\n\t(Exim 4.86_2) (envelope-from )\n\tid 1dugkZ-0003ee-VK\n\tfor kernel-team@lists.ubuntu.com; Wed, 20 Sep 2017 15:17:19 +0000","from 1.general.jsalisbury.us.vpn ([10.172.67.212] helo=salisbury)\n\tby youngberry.canonical.com with esmtpsa\n\t(TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32)\n\t(Exim 4.76) (envelope-from )\n\tid 1dugkZ-0002S8-KJ\n\tfor kernel-team@lists.ubuntu.com; Wed, 20 Sep 2017 15:17:19 +0000","by salisbury (Postfix, from userid 1000)\n\tid 9B1AF7E2808; Wed, 20 Sep 2017 11:17:18 -0400 (EDT)"],"From":"Joseph Salisbury ","To":"kernel-team@lists.ubuntu.com","Subject":"[SRU][Zesty][PATCH 1/2] powerpc/perf: Avoid spurious PMU interrupts\n\tafter idle","Date":"Wed, 20 Sep 2017 11:17:17 -0400","Message-Id":"","X-Mailer":"git-send-email 2.7.4","In-Reply-To":["",""],"References":["",""],"X-BeenThere":"kernel-team@lists.ubuntu.com","X-Mailman-Version":"2.1.20","Precedence":"list","List-Id":"Kernel team discussions ","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","MIME-Version":"1.0","Content-Type":"text/plain; charset=\"utf-8\"","Content-Transfer-Encoding":"base64","Errors-To":"kernel-team-bounces@lists.ubuntu.com","Sender":"\"kernel-team\" "},"content":"From: Nicholas Piggin \n\nBugLink: http://bugs.launchpad.net/bugs/1716491\n\nPOWER9 DD2 can see spurious PMU interrupts after state-loss idle in\nsome conditions.\n\nA solution is to save and reload MMCR0 over state-loss idle.\n\nSigned-off-by: Nicholas Piggin \nAcked-by: Madhavan Srinivasan \nTested-by: Anton Blanchard \nSigned-off-by: Michael Ellerman \n(cherry picked from commit 101dd590a7fa37954540cf3149a1c502c0acc524)\nSigned-off-by: Joseph Salisbury \n---\n arch/powerpc/kernel/idle_book3s.S | 15 ++++++++++++++-\n 1 file changed, 14 insertions(+), 1 deletion(-)","diff":"diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S\nindex fb762ee..e003fb9 100644\n--- a/arch/powerpc/kernel/idle_book3s.S\n+++ b/arch/powerpc/kernel/idle_book3s.S\n@@ -29,6 +29,7 @@\n * Use unused space in the interrupt stack to save and restore\n * registers for winkle support.\n */\n+#define _MMCR0\tGPR0\n #define _SDR1\tGPR3\n #define _RPR\tGPR4\n #define _SPURR\tGPR5\n@@ -282,6 +283,14 @@ power_enter_stop:\n \tb \tpnv_wakeup_noloss\n \n .Lhandle_esl_ec_set:\n+\t/*\n+\t * POWER9 DD2 can incorrectly set PMAO when waking up after a\n+\t * state-loss idle. Saving and restoring MMCR0 over idle is a\n+\t * workaround.\n+\t */\n+\tmfspr\tr4,SPRN_MMCR0\n+\tstd\tr4,_MMCR0(r1)\n+\n /*\n * Check if the requested state is a deep idle state.\n */\n@@ -434,10 +443,14 @@ FTR_SECTION_ELSE_NESTED(70)\n ALT_FTR_SECTION_END_NESTED_IFSET(CPU_FTR_POWER9_DD1, 70)\n \t/*\n \t * Workaround for POWER9, if we lost resources, the ERAT\n-\t * might have been mixed up and needs flushing.\n+\t * might have been mixed up and needs flushing. We also need\n+\t * to reload MMCR0 (see comment above).\n \t */\n \tblt\tcr3,1f\n \tPPC_INVALIDATE_ERAT\n+\tld\tr1,PACAR1(r13)\n+\tld\tr4,_MMCR0(r1)\n+\tmtspr\tSPRN_MMCR0,r4\n 1:\n \t/*\n \t * POWER ISA 3. Use PSSCR to determine if we\n","prefixes":["SRU","Zesty","1/2"]}