From patchwork Thu Nov 7 13:01:58 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: maddy X-Patchwork-Id: 1191141 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4783bp19lZz9sNx for ; Fri, 8 Nov 2019 00:07:50 +1100 (AEDT) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.vnet.ibm.com Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4783bn52MgzF5tm for ; Fri, 8 Nov 2019 00:07:49 +1100 (AEDT) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=linux.vnet.ibm.com (client-ip=148.163.158.5; helo=mx0a-001b2d01.pphosted.com; envelope-from=maddy@linux.vnet.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.vnet.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4783VG2f2YzF50g for ; Fri, 8 Nov 2019 00:02:55 +1100 (AEDT) Received: from pps.filterd (m0098421.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id xA7CuKM7093119 for ; Thu, 7 Nov 2019 08:02:52 -0500 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0a-001b2d01.pphosted.com with ESMTP id 2w4jxaa8m5-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 07 Nov 2019 08:02:51 -0500 Received: from localhost by e06smtp07.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Thu, 7 Nov 2019 13:02:17 -0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id xA7D2Gp150856074 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 7 Nov 2019 13:02:16 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4C4F64C046; Thu, 7 Nov 2019 13:02:16 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 8963B4C059; Thu, 7 Nov 2019 13:02:15 +0000 (GMT) Received: from localhost.in.ibm.com (unknown [9.124.31.133]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 7 Nov 2019 13:02:15 +0000 (GMT) From: Madhavan Srinivasan To: mpe@ellerman.id.au Subject: [PATCH 1/2] powerpc/perf: Add mtmmcr0(FC) after ppc_set_pmu_inuse(1) Date: Thu, 7 Nov 2019 18:31:58 +0530 X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 X-TM-AS-GCONF: 00 x-cbid: 19110713-0028-0000-0000-000003B38C8B X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19110713-0029-0000-0000-00002475EC6F Message-Id: <20191107130159.14146-1-maddy@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-11-07_04:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=427 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1910280000 definitions=main-1911070130 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Madhavan Srinivasan , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" pmu_inuse flag is part of lppaca struct which notifies the hypervisor whether guest/partition is using PMUs. This provides a hint incase of save/restore of PMU registers. And in power_pmu_enable(), linux sets the pmu_inuse flag and then updates the PMU registers. Current sequence in power_pmu_enable() is 1) update pmc_inuse flag 2)update MMCRA, MMCR1, MMCR0 and so on. But with this sequence, there is a window where when updating MMCRA, hypersior could load stale value to MMCR0 which could cause a PMI exception. Patch add a mtmmcr0 with freeze counter bit set right after updating the pmu_inuse flag to avoid any overflow scenarios. --- arch/powerpc/perf/core-book3s.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index 3fb6d265ed17..f455e274281a 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -1351,6 +1351,7 @@ static void power_pmu_enable(struct pmu *pmu) * Then unfreeze the events. */ ppc_set_pmu_inuse(1); + mtspr(SPRN_MMCR0, MMCR0_FC); mtspr(SPRN_MMCRA, cpuhw->mmcr[2] & ~MMCRA_SAMPLE_ENABLE); mtspr(SPRN_MMCR1, cpuhw->mmcr[1]); mtspr(SPRN_MMCR0, (cpuhw->mmcr[0] & ~(MMCR0_PMC1CE | MMCR0_PMCjCE)) From patchwork Thu Nov 7 13:01:59 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: maddy X-Patchwork-Id: 1191143 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4783gy1R18z9sNx for ; Fri, 8 Nov 2019 00:11:24 +1100 (AEDT) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.vnet.ibm.com Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4783gq4jHdzF647 for ; Fri, 8 Nov 2019 00:11:19 +1100 (AEDT) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=linux.vnet.ibm.com (client-ip=148.163.156.1; helo=mx0a-001b2d01.pphosted.com; envelope-from=maddy@linux.vnet.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.vnet.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4783Vp40TLzF5Bx for ; Fri, 8 Nov 2019 00:03:30 +1100 (AEDT) Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id xA7CxYcm088419 for ; Thu, 7 Nov 2019 08:03:28 -0500 Received: from e06smtp05.uk.ibm.com (e06smtp05.uk.ibm.com [195.75.94.101]) by mx0a-001b2d01.pphosted.com with ESMTP id 2w4ge6gfu5-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 07 Nov 2019 08:03:18 -0500 Received: from localhost by e06smtp05.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Thu, 7 Nov 2019 13:02:24 -0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id xA7D2NrZ37814458 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 7 Nov 2019 13:02:23 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0A7314C046; Thu, 7 Nov 2019 13:02:23 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 4664A4C044; Thu, 7 Nov 2019 13:02:22 +0000 (GMT) Received: from localhost.in.ibm.com (unknown [9.124.31.133]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Thu, 7 Nov 2019 13:02:22 +0000 (GMT) From: Madhavan Srinivasan To: mpe@ellerman.id.au Subject: [PATCH 2/2] powerpc/perf: Check pmus_inuse flag in perf_event_print_debug() Date: Thu, 7 Nov 2019 18:31:59 +0530 X-Mailer: git-send-email 2.21.0 In-Reply-To: <20191107130159.14146-1-maddy@linux.vnet.ibm.com> References: <20191107130159.14146-1-maddy@linux.vnet.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 x-cbid: 19110713-0020-0000-0000-000003836A5A X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19110713-0021-0000-0000-000021D99E8F Message-Id: <20191107130159.14146-2-maddy@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-11-07_04:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=828 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1910280000 definitions=main-1911070130 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Madhavan Srinivasan , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" pmu_inuse flag is part of lppaca struct which notifies the hypervisor whether guest/partition is using PMUs. This provides a hint for save/restore of PMU registers. Currently perf_event_print_debug() does not check for pmu_inuse flag and it is not safe to use it to dump PMU SPRs in a CONFIG_PSERIES. Patch adds two things here. 1) An inline ppc_get_pmu_inuse() to get the pmu_inuse value and 2)check in perf_event_print_debug() before dumping the PMU SPRs. ppc_get_pmu_inuse() is based on ppc_set_pmu_inuse() and includes same CONFIG_ checks. --- arch/powerpc/include/asm/pmc.h | 15 +++++++++++++++ arch/powerpc/perf/core-book3s.c | 9 +++++++++ 2 files changed, 24 insertions(+) diff --git a/arch/powerpc/include/asm/pmc.h b/arch/powerpc/include/asm/pmc.h index c6bbe9778d3c..35179d218e2e 100644 --- a/arch/powerpc/include/asm/pmc.h +++ b/arch/powerpc/include/asm/pmc.h @@ -34,11 +34,26 @@ static inline void ppc_set_pmu_inuse(int inuse) #endif } +static inline u8 ppc_get_pmu_inuse(void) +{ +#if defined(CONFIG_PPC_PSERIES) || defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) + if (firmware_has_feature(FW_FEATURE_LPAR)) { +#ifdef CONFIG_PPC_PSERIES + return get_lppaca()->pmcregs_in_use; +#endif + } +#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE + return get_paca()->pmcregs_in_use; +#endif +#endif +} + extern void power4_enable_pmcs(void); #else /* CONFIG_PPC64 */ static inline void ppc_set_pmu_inuse(int inuse) { } +static inline u8 ppc_get_pmu_inuse(void) { } #endif diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c index f455e274281a..855a5f9589ef 100644 --- a/arch/powerpc/perf/core-book3s.c +++ b/arch/powerpc/perf/core-book3s.c @@ -816,6 +816,15 @@ void perf_event_print_debug(void) if (!ppmu->n_counter) return; + /* + * Check pmu_inuse flag. As per PAPR spec, hypersivor + * will save/restore the PMU regs only if pmu_inuse is + * set. If its not enable, values dumped from these SPRs + * may not be valid or useful. + */ + if (!ppc_get_pmu_inuse()) + return; + local_irq_save(flags); pr_info("CPU: %d PMU registers, ppmu = %s n_counters = %d",