From: Hariprasad Nellitheertha <hari@in.ibm.com>
To: linux-kernel@vger.kernel.org, fastboot@osdl.org
Cc: akpm@osdl.org, Suparna Bhattacharya <suparna@in.ibm.com>,
mbligh@aracnet.com, litke@us.ibm.com, ebiederm@xmission.com
Subject: Re: [PATCH][4/6]Register snapshotting before kexec-boot
Date: Tue, 17 Aug 2004 17:39:11 +0530 [thread overview]
Message-ID: <20040817120911.GE3916@in.ibm.com> (raw)
In-Reply-To: <20040817120809.GD3916@in.ibm.com>
[-- Attachment #1: Type: text/plain, Size: 108 bytes --]
Regards, Hari
--
Hariprasad Nellitheertha
Linux Technology Center
India Software Labs
IBM India, Bangalore
[-- Attachment #2: kd-reg-268.patch --]
[-- Type: text/plain, Size: 9739 bytes --]
This patch contains the code for stopping the other cpus and snapshotting
their register values before doing the kexec reboot.
Signed off by Hariprasad Nellitheertha <hari@in.ibm.com>
---
linux-2.6.8.1-hari/arch/i386/kernel/Makefile | 1
linux-2.6.8.1-hari/arch/i386/kernel/crash_dump.c | 98 ++++++++++
linux-2.6.8.1-hari/arch/i386/kernel/machine_kexec.c | 14 +
linux-2.6.8.1-hari/arch/i386/kernel/smp.c | 13 +
linux-2.6.8.1-hari/include/asm-i386/crash_dump.h | 32 +++
linux-2.6.8.1-hari/include/asm-i386/mach-default/irq_vectors.h | 1
linux-2.6.8.1-hari/include/asm-i386/smp.h | 1
7 files changed, 156 insertions(+), 4 deletions(-)
diff -puN arch/i386/kernel/Makefile~kd-reg-268 arch/i386/kernel/Makefile
--- linux-2.6.8.1/arch/i386/kernel/Makefile~kd-reg-268 2004-08-17 17:08:08.000000000 +0530
+++ linux-2.6.8.1-hari/arch/i386/kernel/Makefile 2004-08-17 17:08:18.000000000 +0530
@@ -24,6 +24,7 @@ obj-$(CONFIG_X86_MPPARSE) += mpparse.o
obj-$(CONFIG_X86_LOCAL_APIC) += apic.o nmi.o
obj-$(CONFIG_X86_IO_APIC) += io_apic.o
obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o
+obj-$(CONFIG_CRASH_DUMP) += crash_dump.o
obj-$(CONFIG_X86_NUMAQ) += numaq.o
obj-$(CONFIG_X86_SUMMIT_NUMA) += summit.o
obj-$(CONFIG_MODULES) += module.o
diff -puN /dev/null arch/i386/kernel/crash_dump.c
--- /dev/null 2003-01-30 15:54:37.000000000 +0530
+++ linux-2.6.8.1-hari/arch/i386/kernel/crash_dump.c 2004-08-17 17:08:34.000000000 +0530
@@ -0,0 +1,98 @@
+/*
+ * Architecture specific (i386) functions for kexec based crash dumps.
+ *
+ * Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
+ *
+ * Copyright (C) IBM Corporation, 2004. All rights reserved.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/smp.h>
+#include <linux/irq.h>
+
+#include <asm/crash_dump.h>
+#include <asm/processor.h>
+#include <asm/hardirq.h>
+#include <asm/nmi.h>
+#include <asm/hw_irq.h>
+
+#ifdef CONFIG_SMP
+static atomic_t waiting_for_dump_ipi;
+static int crash_dump_expect_ipi[NR_CPUS];
+extern void crash_dump_send_ipi(void);
+extern void stop_this_cpu(void *);
+
+static int crash_dump_nmi_callback(struct pt_regs *regs, int cpu)
+{
+ if (!crash_dump_expect_ipi[cpu])
+ return 0;
+
+ crash_dump_expect_ipi[cpu] = 0;
+ crash_dump_save_this_cpu(regs, cpu);
+ atomic_dec(&waiting_for_dump_ipi);
+
+ stop_this_cpu(NULL);
+
+ return 1;
+}
+
+void __crash_dump_stop_cpus(void)
+{
+ int i, cpu = smp_processor_id();
+ int other_cpus = num_online_cpus()-1;
+
+ if (other_cpus > 0) {
+ atomic_set(&waiting_for_dump_ipi, other_cpus);
+
+ for (i = 0; i < NR_CPUS; i++)
+ crash_dump_expect_ipi[i] = (i != cpu && cpu_online(i));
+
+ set_nmi_callback(crash_dump_nmi_callback);
+ /* Ensure the new callback function is set before sending
+ * out the IPI
+ */
+ wmb();
+
+ crash_dump_send_ipi();
+ while (atomic_read(&waiting_for_dump_ipi) > 0)
+ cpu_relax();
+
+ unset_nmi_callback();
+ } else {
+ local_irq_disable();
+ disable_local_APIC();
+ local_irq_enable();
+ }
+}
+#else
+void __crash_dump_stop_cpus(void) {}
+#endif
+
+void crash_get_current_regs(struct pt_regs *regs)
+{
+ __asm__ __volatile__("movl %%ebx,%0" : "=m"(regs->ebx));
+ __asm__ __volatile__("movl %%ecx,%0" : "=m"(regs->ecx));
+ __asm__ __volatile__("movl %%edx,%0" : "=m"(regs->edx));
+ __asm__ __volatile__("movl %%esi,%0" : "=m"(regs->esi));
+ __asm__ __volatile__("movl %%edi,%0" : "=m"(regs->edi));
+ __asm__ __volatile__("movl %%ebp,%0" : "=m"(regs->ebp));
+ __asm__ __volatile__("movl %%eax,%0" : "=m"(regs->eax));
+ __asm__ __volatile__("movl %%esp,%0" : "=m"(regs->esp));
+ __asm__ __volatile__("movw %%ss, %%ax;" :"=a"(regs->xss));
+ __asm__ __volatile__("movw %%cs, %%ax;" :"=a"(regs->xcs));
+ __asm__ __volatile__("movw %%ds, %%ax;" :"=a"(regs->xds));
+ __asm__ __volatile__("movw %%es, %%ax;" :"=a"(regs->xes));
+ __asm__ __volatile__("pushfl; popl %0" :"=m"(regs->eflags));
+
+ regs->eip = (unsigned long)current_text_addr();
+}
+
+void crash_dump_save_this_cpu(struct pt_regs *regs, int cpu)
+{
+ crash_smp_current_task[cpu] = (int)current;
+ crash_smp_regs[cpu] = *regs;
+}
+
diff -puN arch/i386/kernel/machine_kexec.c~kd-reg-268 arch/i386/kernel/machine_kexec.c
--- linux-2.6.8.1/arch/i386/kernel/machine_kexec.c~kd-reg-268 2004-08-17 17:08:08.000000000 +0530
+++ linux-2.6.8.1-hari/arch/i386/kernel/machine_kexec.c 2004-08-17 17:08:18.000000000 +0530
@@ -17,8 +17,9 @@
#include <asm/io.h>
#include <asm/apic.h>
#include <asm/cpufeature.h>
-#include <asm/hw_irq.h>
+struct pt_regs crash_smp_regs[NR_CPUS];
+u32 crash_smp_current_task[NR_CPUS];
static void set_idt(void *newidt, __u16 limit)
{
@@ -97,6 +98,14 @@ void __relocate_base_mem(unsigned long b
if (PageReserved(page))
copy_page(dest_addr, src_addr);
}
+
+ /* Now copy over the saved task pointers and the registers
+ * to the end of the reserved area
+ */
+ dest_addr = (void *)(__va(CRASH_BACKUP_BASE + CRASH_BACKUP_SIZE));
+ memcpy(dest_addr, crash_smp_regs, (sizeof(struct pt_regs)*NR_CPUS));
+ dest_addr += sizeof(struct pt_regs)*NR_CPUS;
+ memcpy(dest_addr, crash_smp_current_task, (sizeof(u32)*NR_CPUS));
}
/*
@@ -111,7 +120,8 @@ void machine_kexec(struct kimage *image)
/* switch to an mm where the reboot_code_buffer is identity mapped */
use_mm(&init_mm);
- stop_apics();
+
+ crash_dump_stop_cpus();
/* Interrupts aren't acceptable while we reboot */
local_irq_disable();
diff -puN arch/i386/kernel/smp.c~kd-reg-268 arch/i386/kernel/smp.c
--- linux-2.6.8.1/arch/i386/kernel/smp.c~kd-reg-268 2004-08-17 17:08:08.000000000 +0530
+++ linux-2.6.8.1-hari/arch/i386/kernel/smp.c 2004-08-17 17:08:18.000000000 +0530
@@ -143,6 +143,9 @@ inline void __send_IPI_shortcut(unsigned
*/
cfg = __prepare_ICR(shortcut, vector);
+ if (vector == CRASH_DUMP_VECTOR)
+ cfg = (cfg&~APIC_VECTOR_MASK)|APIC_DM_NMI;
+
/*
* Send the IPI. The write to APIC_ICR fires this off.
*/
@@ -221,6 +224,9 @@ inline void send_IPI_mask_sequence(cpuma
*/
cfg = __prepare_ICR(0, vector);
+ if (vector == CRASH_DUMP_VECTOR)
+ cfg = (cfg&~APIC_VECTOR_MASK)|APIC_DM_NMI;
+
/*
* Send the IPI. The write to APIC_ICR fires this off.
*/
@@ -467,6 +473,11 @@ void flush_tlb_all(void)
on_each_cpu(do_flush_tlb_all, NULL, 1, 1);
}
+void crash_dump_send_ipi(void)
+{
+ send_IPI_allbutself(CRASH_DUMP_VECTOR);
+}
+
/*
* this function sends a 'reschedule' IPI to another CPU.
* it goes straight through and wastes no time serializing
@@ -548,7 +559,7 @@ int smp_call_function (void (*func) (voi
return 0;
}
-static void stop_this_cpu (void * dummy)
+void stop_this_cpu (void * dummy)
{
/*
* Remove this CPU:
diff -puN include/asm-i386/crash_dump.h~kd-reg-268 include/asm-i386/crash_dump.h
--- linux-2.6.8.1/include/asm-i386/crash_dump.h~kd-reg-268 2004-08-17 17:08:09.000000000 +0530
+++ linux-2.6.8.1-hari/include/asm-i386/crash_dump.h 2004-08-17 17:08:18.000000000 +0530
@@ -1,5 +1,7 @@
/* asm-i386/crash_dump.h */
#include <linux/bootmem.h>
+#include <asm/hw_irq.h>
+#include <asm/apic.h>
extern unsigned int dump_enabled;
@@ -8,6 +10,11 @@ void __init find_max_pfn(void);
void __relocate_base_mem(unsigned long, unsigned long);
extern unsigned int crashed;
+extern struct pt_regs crash_smp_regs[NR_CPUS];
+extern u32 crash_smp_current_task[NR_CPUS];
+extern void crash_dump_save_this_cpu(struct pt_regs *, int);
+extern void __crash_dump_stop_cpus(void);
+extern void crash_get_current_regs(struct pt_regs *regs);
#ifdef CONFIG_CRASH_DUMP
#define CRASH_BACKUP_BASE ((unsigned long)CONFIG_BACKUP_BASE * 0x100000)
@@ -28,7 +35,26 @@ static inline void set_saved_max_pfn(voi
static inline void crash_reserve_bootmem(void)
{
if (!dump_enabled)
- reserve_bootmem(CRASH_BACKUP_BASE, CRASH_BACKUP_SIZE);
+ reserve_bootmem(CRASH_BACKUP_BASE, CRASH_BACKUP_SIZE + PAGE_SIZE);
+}
+
+static inline void crash_dump_stop_cpus(void)
+{
+ if (!crashed)
+ stop_apics();
+ else {
+ int cpu = smp_processor_id();
+
+ crash_smp_current_task[cpu] = (int)current;
+ crash_get_current_regs(&crash_smp_regs[cpu]);
+
+ /* This also captures the register states of the other cpus */
+ __crash_dump_stop_cpus();
+#if defined(CONFIG_X86_IO_APIC)
+ disable_IO_APIC();
+#endif
+ disconnect_bsp_APIC();
+ }
}
#else
#define CRASH_BACKUP_BASE 0x08000000
@@ -36,4 +62,8 @@ static inline void crash_reserve_bootmem
static inline void relocate_base_mem(void) {}
static inline void set_saved_max_pfn(void) {}
static inline void crash_reserve_bootmem(void) {}
+static inline void crash_dump_stop_cpus(void)
+{
+ stop_apics();
+}
#endif
diff -puN include/asm-i386/mach-default/irq_vectors.h~kd-reg-268 include/asm-i386/mach-default/irq_vectors.h
--- linux-2.6.8.1/include/asm-i386/mach-default/irq_vectors.h~kd-reg-268 2004-08-17 17:08:09.000000000 +0530
+++ linux-2.6.8.1-hari/include/asm-i386/mach-default/irq_vectors.h 2004-08-17 17:08:18.000000000 +0530
@@ -48,6 +48,7 @@
#define INVALIDATE_TLB_VECTOR 0xfd
#define RESCHEDULE_VECTOR 0xfc
#define CALL_FUNCTION_VECTOR 0xfb
+#define CRASH_DUMP_VECTOR 0xfa
#define THERMAL_APIC_VECTOR 0xf0
/*
diff -puN include/asm-i386/smp.h~kd-reg-268 include/asm-i386/smp.h
--- linux-2.6.8.1/include/asm-i386/smp.h~kd-reg-268 2004-08-17 17:08:09.000000000 +0530
+++ linux-2.6.8.1-hari/include/asm-i386/smp.h 2004-08-17 17:08:18.000000000 +0530
@@ -41,6 +41,7 @@ extern void smp_message_irq(int cpl, voi
extern void smp_invalidate_rcv(void); /* Process an NMI */
extern void (*mtrr_hook) (void);
extern void zap_low_mappings (void);
+extern void stop_this_cpu(void *);
#define MAX_APICID 256
_
next prev parent reply other threads:[~2004-08-17 12:29 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-08-17 12:04 [RFC]Kexec based crash dumping Hariprasad Nellitheertha
2004-08-17 12:05 ` [PATCH][1/6]Documentation Hariprasad Nellitheertha
2004-08-17 12:07 ` [PATCH][2/6]Memory preserving reboot using kexec Hariprasad Nellitheertha
2004-08-17 12:08 ` [PATCH][3/6]Interface for copying the dump pages Hariprasad Nellitheertha
2004-08-17 12:09 ` Hariprasad Nellitheertha [this message]
2004-08-17 12:10 ` [PATCH][5/6]ELF format interface for the dump Hariprasad Nellitheertha
2004-08-17 12:13 ` [PATCH][6/6]Device abstraction for linear/raw view of " Hariprasad Nellitheertha
2004-08-17 22:53 ` Martin J. Bligh
2004-08-18 12:29 ` Hariprasad Nellitheertha
2004-08-17 16:27 ` [PATCH][4/6]Register snapshotting before kexec-boot Dave Hansen
2004-08-18 13:43 ` Theodore Ts'o
2004-08-19 11:59 ` Hariprasad Nellitheertha
2004-08-17 16:17 ` [PATCH][3/6]Interface for copying the dump pages Dave Hansen
2004-08-17 16:01 ` [PATCH][2/6]Memory preserving reboot using kexec Dave Hansen
2004-08-17 22:44 ` [RFC]Kexec based crash dumping Andrew Morton
2004-08-18 12:28 ` Hariprasad Nellitheertha
2004-08-20 8:17 ` [Fastboot] " Eric W. Biederman
2004-08-20 8:05 ` [Fastboot] " Eric W. Biederman
2004-08-20 8:27 ` Hariprasad Nellitheertha
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