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=-8.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 9227DC04AAA for ; Mon, 6 May 2019 08:21:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7085C2082F for ; Mon, 6 May 2019 08:21:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726775AbfEFIV0 (ORCPT ); Mon, 6 May 2019 04:21:26 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:7171 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726657AbfEFIUq (ORCPT ); Mon, 6 May 2019 04:20:46 -0400 Received: from DGGEMS408-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 510C3F015AB8680A8616; Mon, 6 May 2019 16:20:44 +0800 (CST) Received: from euler.huawei.com (10.175.104.193) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.439.0; Mon, 6 May 2019 16:20:41 +0800 From: Wei Li To: , , , , CC: , , , , , , , , Subject: [PATCH 2/3] arm64: Add support for on-demand backtrace of other CPUs Date: Mon, 6 May 2019 16:25:41 +0800 Message-ID: <20190506082542.11357-3-liwei391@huawei.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190506082542.11357-1-liwei391@huawei.com> References: <20190506082542.11357-1-liwei391@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.175.104.193] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org To support backtracing of other CPUs in the system on lockups, add the implementation of arch_trigger_cpumask_backtrace() for arm64. In this patch, we add an arm64 NMI-like IPI based backtracer, referring to the implementation on arm by Russell King and Chris Metcalf. Signed-off-by: Wei Li --- arch/arm64/include/asm/hardirq.h | 2 +- arch/arm64/include/asm/irq.h | 6 ++++++ arch/arm64/kernel/smp.c | 22 +++++++++++++++++++++- 3 files changed, 28 insertions(+), 2 deletions(-) diff --git a/arch/arm64/include/asm/hardirq.h b/arch/arm64/include/asm/hardirq.h index 89691c86640a..a5d94aa59c7c 100644 --- a/arch/arm64/include/asm/hardirq.h +++ b/arch/arm64/include/asm/hardirq.h @@ -24,7 +24,7 @@ #include #include -#define NR_IPI 7 +#define NR_IPI 8 typedef struct { unsigned int __softirq_pending; diff --git a/arch/arm64/include/asm/irq.h b/arch/arm64/include/asm/irq.h index b2b0c6405eb0..28471df488c0 100644 --- a/arch/arm64/include/asm/irq.h +++ b/arch/arm64/include/asm/irq.h @@ -13,5 +13,11 @@ static inline int nr_legacy_irqs(void) return 0; } +#ifdef CONFIG_SMP +extern void arch_trigger_cpumask_backtrace(const cpumask_t *mask, + bool exclude_self); +#define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace +#endif + #endif /* !__ASSEMBLER__ */ #endif diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index bd8fdf6fcd8e..7e862f9124f3 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -35,6 +35,7 @@ #include #include #include +#include #include #include #include @@ -83,7 +84,8 @@ enum ipi_msg_type { IPI_CPU_CRASH_STOP, IPI_TIMER, IPI_IRQ_WORK, - IPI_WAKEUP + IPI_WAKEUP, + IPI_CPU_BACKTRACE }; #ifdef CONFIG_HOTPLUG_CPU @@ -787,6 +789,7 @@ static const char *ipi_types[NR_IPI] __tracepoint_string = { S(IPI_TIMER, "Timer broadcast interrupts"), S(IPI_IRQ_WORK, "IRQ work interrupts"), S(IPI_WAKEUP, "CPU wake-up interrupts"), + S(IPI_CPU_BACKTRACE, "Backtrace interrupts"), }; static void smp_cross_call(const struct cpumask *target, unsigned int ipinr) @@ -946,6 +949,12 @@ void handle_IPI(int ipinr, struct pt_regs *regs) break; #endif + case IPI_CPU_BACKTRACE: + nmi_enter(); + nmi_cpu_backtrace(regs); + nmi_exit(); + break; + default: pr_crit("CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr); break; @@ -1070,4 +1079,15 @@ bool cpus_are_stuck_in_kernel(void) void ipi_gic_nmi_setup(void __iomem *base) { + gic_sgi_set_prio(base, IPI_CPU_BACKTRACE, GICD_INT_NMI_PRI); +} + +static void raise_nmi(cpumask_t *mask) +{ + smp_cross_call(mask, IPI_CPU_BACKTRACE); +} + +void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) +{ + nmi_trigger_cpumask_backtrace(mask, exclude_self, raise_nmi); } -- 2.17.1