From mboxrd@z Thu Jan 1 00:00:00 1970 From: geoff@infradead.org (Geoff Levand) Date: Mon, 19 Oct 2015 23:38:54 +0000 Subject: [PATCH 12/16] arm64: kdump: implement machine_crash_shutdown() In-Reply-To: References: Message-ID: <10adbaf4a069aabc3d774963cf6613dfa46f923d.1445297709.git.geoff@infradead.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: AKASHI Takahiro kdump calls machine_crash_shutdown() to shut down non-boot cpus and save registers' status in per-cpu ELF notes before starting the crash dump kernel. See kernel_kexec(). ipi_cpu_stop() is a bit modified and used to support this behavior. Signed-off-by: AKASHI Takahiro --- arch/arm64/include/asm/kexec.h | 34 +++++++++++++++++++++++++++++++++- arch/arm64/kernel/machine_kexec.c | 30 +++++++++++++++++++++++++++++- arch/arm64/kernel/smp.c | 16 ++++++++++++++-- 3 files changed, 76 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h index 46d63cd..555a955 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, #16 * 0]\n" + "stp x2, x3, [%3, #16 * 1]\n" + "stp x4, x5, [%3, #16 * 2]\n" + "stp x6, x7, [%3, #16 * 3]\n" + "stp x8, x9, [%3, #16 * 4]\n" + "stp x10, x11, [%3, #16 * 5]\n" + "stp x12, x13, [%3, #16 * 6]\n" + "stp x14, x15, [%3, #16 * 7]\n" + "stp x16, x17, [%3, #16 * 8]\n" + "stp x18, x19, [%3, #16 * 9]\n" + "stp x20, x21, [%3, #16 * 10]\n" + "stp x22, x23, [%3, #16 * 11]\n" + "stp x24, x25, [%3, #16 * 12]\n" + "stp x26, x27, [%3, #16 * 13]\n" + "stp x28, x29, [%3, #16 * 14]\n" + "str x30, [%3, #16 * 15]\n" + "mov %0, sp\n" + "adr %1, 1f\n" + "mrs %2, spsr_el1\n" + "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 362f719..f315ee4 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -9,6 +9,7 @@ * published by the Free Software Foundation. */ +#include #include #include #include @@ -28,6 +29,8 @@ extern unsigned long arm64_kexec_kimage_start_offset; static unsigned long kimage_head; static unsigned long kimage_start; +bool in_crash_kexec; + /** * kexec_is_dtb - Helper routine to check the device tree header signature. */ @@ -198,7 +201,32 @@ void machine_kexec(struct kimage *image) soft_restart(reboot_code_buffer_phys); } +/** + * 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 never 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 boot cpu */ + crash_save_cpu(regs, smp_processor_id()); + + pr_info("Loading crashdump kernel...\n"); } diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index dbdaacd..88aec66 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -37,6 +37,7 @@ #include #include #include +#include #include #include @@ -54,6 +55,8 @@ #include #include +#include "cpu-reset.h" + #define CREATE_TRACE_POINTS #include @@ -679,8 +682,12 @@ 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) { +#ifdef CONFIG_KEXEC + /* printing messages may slow down the shutdown. */ + if (!in_crash_kexec) +#endif if (system_state == SYSTEM_BOOTING || system_state == SYSTEM_RUNNING) { raw_spin_lock(&stop_lock); @@ -693,6 +700,11 @@ static void ipi_cpu_stop(unsigned int cpu) local_irq_disable(); +#ifdef CONFIG_KEXEC + if (in_crash_kexec) + crash_save_cpu(regs, cpu); +#endif /* CONFIG_KEXEC */ + while (1) cpu_relax(); } @@ -723,7 +735,7 @@ 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; -- 2.5.0 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Message-Id: <10adbaf4a069aabc3d774963cf6613dfa46f923d.1445297709.git.geoff@infradead.org> In-Reply-To: References: From: Geoff Levand Subject: [PATCH 12/16] arm64: kdump: implement machine_crash_shutdown() Date: Mon, 19 Oct 2015 23:38:54 +0000 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Catalin Marinas , Will Deacon Cc: Mark Rutland , AKASHI@infradead.org, marc.zyngier@arm.com, kexec@lists.infradead.org, Takahiro , linux-arm-kernel@lists.infradead.org, christoffer.dall@linaro.org From: AKASHI Takahiro kdump calls machine_crash_shutdown() to shut down non-boot cpus and save registers' status in per-cpu ELF notes before starting the crash dump kernel. See kernel_kexec(). ipi_cpu_stop() is a bit modified and used to support this behavior. Signed-off-by: AKASHI Takahiro --- arch/arm64/include/asm/kexec.h | 34 +++++++++++++++++++++++++++++++++- arch/arm64/kernel/machine_kexec.c | 30 +++++++++++++++++++++++++++++- arch/arm64/kernel/smp.c | 16 ++++++++++++++-- 3 files changed, 76 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/kexec.h b/arch/arm64/include/asm/kexec.h index 46d63cd..555a955 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, #16 * 0]\n" + "stp x2, x3, [%3, #16 * 1]\n" + "stp x4, x5, [%3, #16 * 2]\n" + "stp x6, x7, [%3, #16 * 3]\n" + "stp x8, x9, [%3, #16 * 4]\n" + "stp x10, x11, [%3, #16 * 5]\n" + "stp x12, x13, [%3, #16 * 6]\n" + "stp x14, x15, [%3, #16 * 7]\n" + "stp x16, x17, [%3, #16 * 8]\n" + "stp x18, x19, [%3, #16 * 9]\n" + "stp x20, x21, [%3, #16 * 10]\n" + "stp x22, x23, [%3, #16 * 11]\n" + "stp x24, x25, [%3, #16 * 12]\n" + "stp x26, x27, [%3, #16 * 13]\n" + "stp x28, x29, [%3, #16 * 14]\n" + "str x30, [%3, #16 * 15]\n" + "mov %0, sp\n" + "adr %1, 1f\n" + "mrs %2, spsr_el1\n" + "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 362f719..f315ee4 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -9,6 +9,7 @@ * published by the Free Software Foundation. */ +#include #include #include #include @@ -28,6 +29,8 @@ extern unsigned long arm64_kexec_kimage_start_offset; static unsigned long kimage_head; static unsigned long kimage_start; +bool in_crash_kexec; + /** * kexec_is_dtb - Helper routine to check the device tree header signature. */ @@ -198,7 +201,32 @@ void machine_kexec(struct kimage *image) soft_restart(reboot_code_buffer_phys); } +/** + * 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 never 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 boot cpu */ + crash_save_cpu(regs, smp_processor_id()); + + pr_info("Loading crashdump kernel...\n"); } diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index dbdaacd..88aec66 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -37,6 +37,7 @@ #include #include #include +#include #include #include @@ -54,6 +55,8 @@ #include #include +#include "cpu-reset.h" + #define CREATE_TRACE_POINTS #include @@ -679,8 +682,12 @@ 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) { +#ifdef CONFIG_KEXEC + /* printing messages may slow down the shutdown. */ + if (!in_crash_kexec) +#endif if (system_state == SYSTEM_BOOTING || system_state == SYSTEM_RUNNING) { raw_spin_lock(&stop_lock); @@ -693,6 +700,11 @@ static void ipi_cpu_stop(unsigned int cpu) local_irq_disable(); +#ifdef CONFIG_KEXEC + if (in_crash_kexec) + crash_save_cpu(regs, cpu); +#endif /* CONFIG_KEXEC */ + while (1) cpu_relax(); } @@ -723,7 +735,7 @@ 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; -- 2.5.0 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec