Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933967AbbDXHyK (ORCPT ); Fri, 24 Apr 2015 03:54:10 -0400 Received: from mail-pd0-f169.google.com ([209.85.192.169]:35811 "EHLO mail-pd0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933681AbbDXHyD (ORCPT ); Fri, 24 Apr 2015 03:54:03 -0400 From: AKASHI Takahiro To: catalin.marinas@arm.com, will.deacon@arm.com, vgoyal@redhat.com, hbabus@us.ibm.com Cc: geoff@infradead.org, broonie@kernel.org, david.griego@linaro.org, kexec@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linaro-kernel@lists.linaro.org, linux-kernel@vger.kernel.org, AKASHI Takahiro Subject: [v2 2/5] arm64: kdump: implement machine_crash_shutdown() Date: Fri, 24 Apr 2015 16:53:05 +0900 Message-Id: <1429861989-8417-3-git-send-email-takahiro.akashi@linaro.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1429861989-8417-1-git-send-email-takahiro.akashi@linaro.org> References: <1429861989-8417-1-git-send-email-takahiro.akashi@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5358 Lines: 196 kdump calls machine_crash_shutdown() to shut down non-boot cpus and save per-cpu general-purpose registers before restarting the crash dump kernel. See kernel_kexec(). ipi_cpu_stop() is used and a bit modified to support this behavior. Signed-off-by: AKASHI Takahiro --- arch/arm64/include/asm/kexec.h | 34 ++++++++++++++++++++++- arch/arm64/kernel/machine_kexec.c | 55 ++++++++++++++++++++++++++++++++++++- arch/arm64/kernel/smp.c | 12 ++++++-- 3 files changed, 97 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h index 3530ff5..eaf3fcb 100644 --- a/arch/arm64/include/asm/kexec.h +++ b/arch/arm64/include/asm/kexec.h @@ -30,6 +30,8 @@ #if !defined(__ASSEMBLY__) +extern bool in_crash_kexec; + /** * crash_setup_regs() - save registers for the panic kernel * @@ -40,7 +42,37 @@ static inline void crash_setup_regs(struct pt_regs *newregs, struct pt_regs *oldregs) { - /* Empty routine needed to avoid build errors. */ + if (oldregs) { + memcpy(newregs, oldregs, sizeof(*newregs)); + } else { + __asm__ __volatile__ ( + "stp x0, x1, [%3]\n\t" + "stp x2, x3, [%3, 0x10]\n\t" + "stp x4, x5, [%3, 0x20]\n\t" + "stp x6, x7, [%3, 0x30]\n\t" + "stp x8, x9, [%3, 0x40]\n\t" + "stp x10, x11, [%3, 0x50]\n\t" + "stp x12, x13, [%3, 0x60]\n\t" + "stp x14, x15, [%3, 0x70]\n\t" + "stp x16, x17, [%3, 0x80]\n\t" + "stp x18, x19, [%3, 0x90]\n\t" + "stp x20, x21, [%3, 0xa0]\n\t" + "stp x22, x23, [%3, 0xb0]\n\t" + "stp x24, x25, [%3, 0xc0]\n\t" + "stp x26, x27, [%3, 0xd0]\n\t" + "stp x28, x29, [%3, 0xe0]\n\t" + "str x30, [%3, 0xf0]\n\t" + "mov %0, sp\n\t" + "adr %1, 1f\n\t" + "mrs %2, spsr_el1\n\t" + "1:" + : "=r" (newregs->sp), + "=r" (newregs->pc), + "=r" (newregs->pstate) + : "r" (&newregs->regs) + : "memory" + ); + } } #endif /* !defined(__ASSEMBLY__) */ diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c index fd6b742..6f7887b 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -9,6 +9,8 @@ * published by the Free Software Foundation. */ +#include +#include #include #include #include @@ -24,6 +26,8 @@ extern unsigned long arm64_kexec_dtb_addr; extern unsigned long arm64_kexec_kimage_head; extern unsigned long arm64_kexec_kimage_start; +bool in_crash_kexec = false; + /** * kexec_is_dtb - Helper routine to check the device tree header signature. */ @@ -178,7 +182,56 @@ void machine_kexec(struct kimage *image) soft_restart(reboot_code_buffer_phys); } +static void machine_kexec_mask_interrupts(void) +{ + unsigned int i; + struct irq_desc *desc; + + for_each_irq_desc(i, desc) { + struct irq_chip *chip; + + chip = irq_desc_get_chip(desc); + if (!chip) + continue; + + if (chip->irq_eoi && irqd_irq_inprogress(&desc->irq_data)) + chip->irq_eoi(&desc->irq_data); + + if (chip->irq_mask) + chip->irq_mask(&desc->irq_data); + + if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data)) + chip->irq_disable(&desc->irq_data); + } +} + +/** + * machine_crash_shutdown - shutdown non-boot cpus and save registers + */ void machine_crash_shutdown(struct pt_regs *regs) { - /* Empty routine needed to avoid build errors. */ + struct pt_regs dummy_regs; + int cpu; + + local_irq_disable(); + + in_crash_kexec = true; + + /* + * clear and initialize the per-cpu info. This is necessary + * because, otherwise, slots for offline cpus would not be + * filled up. See smp_send_stop(). + */ + memset(&dummy_regs, 0, sizeof(dummy_regs)); + for_each_possible_cpu(cpu) + crash_save_cpu(&dummy_regs, cpu); + + /* shutdown non-boot cpus */ + smp_send_stop(); + + /* for this cpu */ + crash_save_cpu(regs, smp_processor_id()); + machine_kexec_mask_interrupts(); + + pr_info("Loading crashdump kernel...\n"); } diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index ffe8e1b..cf7f361 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -36,6 +36,7 @@ #include #include #include +#include #include #include @@ -542,7 +543,7 @@ static DEFINE_RAW_SPINLOCK(stop_lock); /* * ipi_cpu_stop - handle IPI from smp_send_stop() */ -static void ipi_cpu_stop(unsigned int cpu) +static void ipi_cpu_stop(unsigned int cpu, struct pt_regs *regs) { if (system_state == SYSTEM_BOOTING || system_state == SYSTEM_RUNNING) { @@ -556,6 +557,13 @@ static void ipi_cpu_stop(unsigned int cpu) local_irq_disable(); +#ifdef CONFIG_KEXEC + if (in_crash_kexec) { + crash_save_cpu(regs, cpu); + flush_cache_all(); + } +#endif /* CONFIG_KEXEC */ + while (1) cpu_relax(); } @@ -586,7 +594,7 @@ void handle_IPI(int ipinr, struct pt_regs *regs) case IPI_CPU_STOP: irq_enter(); - ipi_cpu_stop(cpu); + ipi_cpu_stop(cpu, regs); irq_exit(); break; -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/