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Message-ID: <20120523112915.GA19944@gmail.com>
Date: Wed, 23 May 2012 13:29:16 +0200
From: Ingo Molnar <mingo@...nel.org>
To: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: linux-kernel@...r.kernel.org, Thomas Gleixner <tglx@...utronix.de>,
"H. Peter Anvin" <hpa@...or.com>, Don Zickus <dzickus@...hat.com>,
Andrew Morton <akpm@...ux-foundation.org>
Subject: [GIT PULL] x86/reboot changes for v3.5
Linus,
Please pull the latest x86-reboot-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-reboot-for-linus
HEAD: 3aac27aba79b7c52e709ef6de0f7d8139caedc01 x86/reboot: Update nonmi_ipi parameter
The biggest change is a gentler method of rebooting/stopping via
IRQs first and then via NMIs. There are several cleanups in the
tree as well.
Thanks,
Ingo
------------------>
Don Zickus (3):
Revert "x86, reboot: Use NMI instead of REBOOT_VECTOR to stop cpus"
x86/reboot: Use NMI to assist in shutting down if IRQ fails
x86/reboot: Update nonmi_ipi parameter
He Chunhui (1):
x86, boot: Fix port argument to inl() function
Michael D Labriola (2):
x86/reboot: Reduce to a single DMI table for reboot quirks
x86/reboot: Clean up coding style
arch/x86/boot/boot.h | 2 +-
arch/x86/kernel/reboot.c | 277 ++++++++++++++++++++++++-----------------------
arch/x86/kernel/smp.c | 100 ++++++++---------
3 files changed, 186 insertions(+), 193 deletions(-)
diff --git a/arch/x86/boot/boot.h b/arch/x86/boot/boot.h
index c7093bd..18997e5 100644
--- a/arch/x86/boot/boot.h
+++ b/arch/x86/boot/boot.h
@@ -67,7 +67,7 @@ static inline void outl(u32 v, u16 port)
{
asm volatile("outl %0,%1" : : "a" (v), "dN" (port));
}
-static inline u32 inl(u32 port)
+static inline u32 inl(u16 port)
{
u32 v;
asm volatile("inl %1,%0" : "=a" (v) : "dN" (port));
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index d840e69..77215c2 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -39,7 +39,8 @@ static int reboot_mode;
enum reboot_type reboot_type = BOOT_ACPI;
int reboot_force;
-/* This variable is used privately to keep track of whether or not
+/*
+ * This variable is used privately to keep track of whether or not
* reboot_type is still set to its default value (i.e., reboot= hasn't
* been set on the command line). This is needed so that we can
* suppress DMI scanning for reboot quirks. Without it, it's
@@ -51,7 +52,8 @@ static int reboot_default = 1;
static int reboot_cpu = -1;
#endif
-/* This is set if we need to go through the 'emergency' path.
+/*
+ * This is set if we need to go through the 'emergency' path.
* When machine_emergency_restart() is called, we may be on
* an inconsistent state and won't be able to do a clean cleanup
*/
@@ -60,22 +62,24 @@ static int reboot_emergency;
/* This is set by the PCI code if either type 1 or type 2 PCI is detected */
bool port_cf9_safe = false;
-/* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
- warm Don't set the cold reboot flag
- cold Set the cold reboot flag
- bios Reboot by jumping through the BIOS (only for X86_32)
- smp Reboot by executing reset on BSP or other CPU (only for X86_32)
- triple Force a triple fault (init)
- kbd Use the keyboard controller. cold reset (default)
- acpi Use the RESET_REG in the FADT
- efi Use efi reset_system runtime service
- pci Use the so-called "PCI reset register", CF9
- force Avoid anything that could hang.
+/*
+ * reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
+ * warm Don't set the cold reboot flag
+ * cold Set the cold reboot flag
+ * bios Reboot by jumping through the BIOS (only for X86_32)
+ * smp Reboot by executing reset on BSP or other CPU (only for X86_32)
+ * triple Force a triple fault (init)
+ * kbd Use the keyboard controller. cold reset (default)
+ * acpi Use the RESET_REG in the FADT
+ * efi Use efi reset_system runtime service
+ * pci Use the so-called "PCI reset register", CF9
+ * force Avoid anything that could hang.
*/
static int __init reboot_setup(char *str)
{
for (;;) {
- /* Having anything passed on the command line via
+ /*
+ * Having anything passed on the command line via
* reboot= will cause us to disable DMI checking
* below.
*/
@@ -98,9 +102,11 @@ static int __init reboot_setup(char *str)
if (isdigit(*(str+2)))
reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
}
- /* we will leave sorting out the final value
- when we are ready to reboot, since we might not
- have detected BSP APIC ID or smp_num_cpu */
+ /*
+ * We will leave sorting out the final value
+ * when we are ready to reboot, since we might not
+ * have detected BSP APIC ID or smp_num_cpu
+ */
break;
#endif /* CONFIG_SMP */
@@ -150,6 +156,82 @@ static int __init set_bios_reboot(const struct dmi_system_id *d)
return 0;
}
+extern const unsigned char machine_real_restart_asm[];
+extern const u64 machine_real_restart_gdt[3];
+
+void machine_real_restart(unsigned int type)
+{
+ void *restart_va;
+ unsigned long restart_pa;
+ void (*restart_lowmem)(unsigned int);
+ u64 *lowmem_gdt;
+
+ local_irq_disable();
+
+ /*
+ * Write zero to CMOS register number 0x0f, which the BIOS POST
+ * routine will recognize as telling it to do a proper reboot. (Well
+ * that's what this book in front of me says -- it may only apply to
+ * the Phoenix BIOS though, it's not clear). At the same time,
+ * disable NMIs by setting the top bit in the CMOS address register,
+ * as we're about to do peculiar things to the CPU. I'm not sure if
+ * `outb_p' is needed instead of just `outb'. Use it to be on the
+ * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
+ */
+ spin_lock(&rtc_lock);
+ CMOS_WRITE(0x00, 0x8f);
+ spin_unlock(&rtc_lock);
+
+ /*
+ * Switch back to the initial page table.
+ */
+ load_cr3(initial_page_table);
+
+ /*
+ * Write 0x1234 to absolute memory location 0x472. The BIOS reads
+ * this on booting to tell it to "Bypass memory test (also warm
+ * boot)". This seems like a fairly standard thing that gets set by
+ * REBOOT.COM programs, and the previous reset routine did this
+ * too. */
+ *((unsigned short *)0x472) = reboot_mode;
+
+ /* Patch the GDT in the low memory trampoline */
+ lowmem_gdt = TRAMPOLINE_SYM(machine_real_restart_gdt);
+
+ restart_va = TRAMPOLINE_SYM(machine_real_restart_asm);
+ restart_pa = virt_to_phys(restart_va);
+ restart_lowmem = (void (*)(unsigned int))restart_pa;
+
+ /* GDT[0]: GDT self-pointer */
+ lowmem_gdt[0] =
+ (u64)(sizeof(machine_real_restart_gdt) - 1) +
+ ((u64)virt_to_phys(lowmem_gdt) << 16);
+ /* GDT[1]: 64K real mode code segment */
+ lowmem_gdt[1] =
+ GDT_ENTRY(0x009b, restart_pa, 0xffff);
+
+ /* Jump to the identity-mapped low memory code */
+ restart_lowmem(type);
+}
+#ifdef CONFIG_APM_MODULE
+EXPORT_SYMBOL(machine_real_restart);
+#endif
+
+#endif /* CONFIG_X86_32 */
+
+/*
+ * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
+ */
+static int __init set_pci_reboot(const struct dmi_system_id *d)
+{
+ if (reboot_type != BOOT_CF9) {
+ reboot_type = BOOT_CF9;
+ printk(KERN_INFO "%s series board detected. "
+ "Selecting PCI-method for reboots.\n", d->ident);
+ }
+ return 0;
+}
+
static int __init set_kbd_reboot(const struct dmi_system_id *d)
{
if (reboot_type != BOOT_KBD) {
@@ -159,7 +241,12 @@ static int __init set_kbd_reboot(const struct dmi_system_id *d)
return 0;
}
+/*
+ * This is a single dmi_table handling all reboot quirks. Note that
+ * REBOOT_BIOS is only available for 32bit
+ */
static struct dmi_system_id __initdata reboot_dmi_table[] = {
+#ifdef CONFIG_X86_32
{ /* Handle problems with rebooting on Dell E520's */
.callback = set_bios_reboot,
.ident = "Dell E520",
@@ -184,7 +271,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = {
DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
},
},
- { /* Handle problems with rebooting on Dell Optiplex 745's SFF*/
+ { /* Handle problems with rebooting on Dell Optiplex 745's SFF */
.callback = set_bios_reboot,
.ident = "Dell OptiPlex 745",
.matches = {
@@ -192,7 +279,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = {
DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
},
},
- { /* Handle problems with rebooting on Dell Optiplex 745's DFF*/
+ { /* Handle problems with rebooting on Dell Optiplex 745's DFF */
.callback = set_bios_reboot,
.ident = "Dell OptiPlex 745",
.matches = {
@@ -201,7 +288,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = {
DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
},
},
- { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
+ { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
.callback = set_bios_reboot,
.ident = "Dell OptiPlex 745",
.matches = {
@@ -210,7 +297,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = {
DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
},
},
- { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
+ { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
.callback = set_bios_reboot,
.ident = "Dell OptiPlex 330",
.matches = {
@@ -219,7 +306,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = {
DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
},
},
- { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
+ { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
.callback = set_bios_reboot,
.ident = "Dell OptiPlex 360",
.matches = {
@@ -228,7 +315,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = {
DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
},
},
- { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G*/
+ { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */
.callback = set_bios_reboot,
.ident = "Dell OptiPlex 760",
.matches = {
@@ -301,7 +388,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = {
DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"),
},
},
- { /* Handle problems with rebooting on ASUS P4S800 */
+ { /* Handle problems with rebooting on ASUS P4S800 */
.callback = set_bios_reboot,
.ident = "ASUS P4S800",
.matches = {
@@ -309,7 +396,9 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = {
DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
},
},
- { /* Handle reboot issue on Acer Aspire one */
+#endif /* CONFIG_X86_32 */
+
+ { /* Handle reboot issue on Acer Aspire one */
.callback = set_kbd_reboot,
.ident = "Acer Aspire One A110",
.matches = {
@@ -317,96 +406,6 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = {
DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
},
},
- { }
-};
-
-static int __init reboot_init(void)
-{
- /* Only do the DMI check if reboot_type hasn't been overridden
- * on the command line
- */
- if (reboot_default) {
- dmi_check_system(reboot_dmi_table);
- }
- return 0;
-}
-core_initcall(reboot_init);
-
-extern const unsigned char machine_real_restart_asm[];
-extern const u64 machine_real_restart_gdt[3];
-
-void machine_real_restart(unsigned int type)
-{
- void *restart_va;
- unsigned long restart_pa;
- void (*restart_lowmem)(unsigned int);
- u64 *lowmem_gdt;
-
- local_irq_disable();
-
- /* Write zero to CMOS register number 0x0f, which the BIOS POST
- routine will recognize as telling it to do a proper reboot. (Well
- that's what this book in front of me says -- it may only apply to
- the Phoenix BIOS though, it's not clear). At the same time,
- disable NMIs by setting the top bit in the CMOS address register,
- as we're about to do peculiar things to the CPU. I'm not sure if
- `outb_p' is needed instead of just `outb'. Use it to be on the
- safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.)
- */
- spin_lock(&rtc_lock);
- CMOS_WRITE(0x00, 0x8f);
- spin_unlock(&rtc_lock);
-
- /*
- * Switch back to the initial page table.
- */
- load_cr3(initial_page_table);
-
- /* Write 0x1234 to absolute memory location 0x472. The BIOS reads
- this on booting to tell it to "Bypass memory test (also warm
- boot)". This seems like a fairly standard thing that gets set by
- REBOOT.COM programs, and the previous reset routine did this
- too. */
- *((unsigned short *)0x472) = reboot_mode;
-
- /* Patch the GDT in the low memory trampoline */
- lowmem_gdt = TRAMPOLINE_SYM(machine_real_restart_gdt);
-
- restart_va = TRAMPOLINE_SYM(machine_real_restart_asm);
- restart_pa = virt_to_phys(restart_va);
- restart_lowmem = (void (*)(unsigned int))restart_pa;
-
- /* GDT[0]: GDT self-pointer */
- lowmem_gdt[0] =
- (u64)(sizeof(machine_real_restart_gdt) - 1) +
- ((u64)virt_to_phys(lowmem_gdt) << 16);
- /* GDT[1]: 64K real mode code segment */
- lowmem_gdt[1] =
- GDT_ENTRY(0x009b, restart_pa, 0xffff);
-
- /* Jump to the identity-mapped low memory code */
- restart_lowmem(type);
-}
-#ifdef CONFIG_APM_MODULE
-EXPORT_SYMBOL(machine_real_restart);
-#endif
-
-#endif /* CONFIG_X86_32 */
-
-/*
- * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
- */
-static int __init set_pci_reboot(const struct dmi_system_id *d)
-{
- if (reboot_type != BOOT_CF9) {
- reboot_type = BOOT_CF9;
- printk(KERN_INFO "%s series board detected. "
- "Selecting PCI-method for reboots.\n", d->ident);
- }
- return 0;
-}
-
-static struct dmi_system_id __initdata pci_reboot_dmi_table[] = {
{ /* Handle problems with rebooting on Apple MacBook5 */
.callback = set_pci_reboot,
.ident = "Apple MacBook5",
@@ -474,17 +473,17 @@ static struct dmi_system_id __initdata pci_reboot_dmi_table[] = {
{ }
};
-static int __init pci_reboot_init(void)
+static int __init reboot_init(void)
{
- /* Only do the DMI check if reboot_type hasn't been overridden
+ /*
+ * Only do the DMI check if reboot_type hasn't been overridden
* on the command line
*/
- if (reboot_default) {
- dmi_check_system(pci_reboot_dmi_table);
- }
+ if (reboot_default)
+ dmi_check_system(reboot_dmi_table);
return 0;
}
-core_initcall(pci_reboot_init);
+core_initcall(reboot_init);
static inline void kb_wait(void)
{
@@ -502,14 +501,14 @@ static void vmxoff_nmi(int cpu, struct pt_regs *regs)
cpu_emergency_vmxoff();
}
-/* Use NMIs as IPIs to tell all CPUs to disable virtualization
- */
+/* Use NMIs as IPIs to tell all CPUs to disable virtualization */
static void emergency_vmx_disable_all(void)
{
/* Just make sure we won't change CPUs while doing this */
local_irq_disable();
- /* We need to disable VMX on all CPUs before rebooting, otherwise
+ /*
+ * We need to disable VMX on all CPUs before rebooting, otherwise
* we risk hanging up the machine, because the CPU ignore INIT
* signals when VMX is enabled.
*
@@ -528,8 +527,7 @@ static void emergency_vmx_disable_all(void)
* is still enabling VMX.
*/
if (cpu_has_vmx() && cpu_vmx_enabled()) {
- /* Disable VMX on this CPU.
- */
+ /* Disable VMX on this CPU. */
cpu_vmxoff();
/* Halt and disable VMX on the other CPUs */
@@ -574,12 +572,12 @@ static void native_machine_emergency_restart(void)
/* Could also try the reset bit in the Hammer NB */
switch (reboot_type) {
case BOOT_KBD:
- mach_reboot_fixups(); /* for board specific fixups */
+ mach_reboot_fixups(); /* For board specific fixups */
for (i = 0; i < 10; i++) {
kb_wait();
udelay(50);
- outb(0xfe, 0x64); /* pulse reset low */
+ outb(0xfe, 0x64); /* Pulse reset low */
udelay(50);
}
if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
@@ -621,7 +619,7 @@ static void native_machine_emergency_restart(void)
case BOOT_CF9:
port_cf9_safe = true;
- /* fall through */
+ /* Fall through */
case BOOT_CF9_COND:
if (port_cf9_safe) {
@@ -659,7 +657,8 @@ void native_machine_shutdown(void)
/* Make certain I only run on the appropriate processor */
set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
- /* O.K Now that I'm on the appropriate processor,
+ /*
+ * O.K Now that I'm on the appropriate processor,
* stop all of the others.
*/
stop_other_cpus();
@@ -697,12 +696,11 @@ static void native_machine_restart(char *__unused)
static void native_machine_halt(void)
{
- /* stop other cpus and apics */
+ /* Stop other cpus and apics */
machine_shutdown();
tboot_shutdown(TB_SHUTDOWN_HALT);
- /* stop this cpu */
stop_this_cpu(NULL);
}
@@ -713,7 +711,7 @@ static void native_machine_power_off(void)
machine_shutdown();
pm_power_off();
}
- /* a fallback in case there is no PM info available */
+ /* A fallback in case there is no PM info available */
tboot_shutdown(TB_SHUTDOWN_HALT);
}
@@ -775,7 +773,8 @@ static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
cpu = raw_smp_processor_id();
- /* Don't do anything if this handler is invoked on crashing cpu.
+ /*
+ * Don't do anything if this handler is invoked on crashing cpu.
* Otherwise, system will completely hang. Crashing cpu can get
* an NMI if system was initially booted with nmi_watchdog parameter.
*/
@@ -799,7 +798,8 @@ static void smp_send_nmi_allbutself(void)
apic->send_IPI_allbutself(NMI_VECTOR);
}
-/* Halt all other CPUs, calling the specified function on each of them
+/*
+ * Halt all other CPUs, calling the specified function on each of them
*
* This function can be used to halt all other CPUs on crash
* or emergency reboot time. The function passed as parameter
@@ -810,7 +810,7 @@ void nmi_shootdown_cpus(nmi_shootdown_cb callback)
unsigned long msecs;
local_irq_disable();
- /* Make a note of crashing cpu. Will be used in NMI callback.*/
+ /* Make a note of crashing cpu. Will be used in NMI callback. */
crashing_cpu = safe_smp_processor_id();
shootdown_callback = callback;
@@ -819,8 +819,9 @@ void nmi_shootdown_cpus(nmi_shootdown_cb callback)
/* Would it be better to replace the trap vector here? */
if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
NMI_FLAG_FIRST, "crash"))
- return; /* return what? */
- /* Ensure the new callback function is set before sending
+ return; /* Return what? */
+ /*
+ * Ensure the new callback function is set before sending
* out the NMI
*/
wmb();
diff --git a/arch/x86/kernel/smp.c b/arch/x86/kernel/smp.c
index 66c74f4..48d2b7d 100644
--- a/arch/x86/kernel/smp.c
+++ b/arch/x86/kernel/smp.c
@@ -109,6 +109,9 @@
* about nothing of note with C stepping upwards.
*/
+static atomic_t stopping_cpu = ATOMIC_INIT(-1);
+static bool smp_no_nmi_ipi = false;
+
/*
* this function sends a 'reschedule' IPI to another CPU.
* it goes straight through and wastes no time serializing
@@ -149,8 +152,6 @@ void native_send_call_func_ipi(const struct cpumask *mask)
free_cpumask_var(allbutself);
}
-static atomic_t stopping_cpu = ATOMIC_INIT(-1);
-
static int smp_stop_nmi_callback(unsigned int val, struct pt_regs *regs)
{
/* We are registered on stopping cpu too, avoid spurious NMI */
@@ -162,7 +163,19 @@ static int smp_stop_nmi_callback(unsigned int val, struct pt_regs *regs)
return NMI_HANDLED;
}
-static void native_nmi_stop_other_cpus(int wait)
+/*
+ * this function calls the 'stop' function on all other CPUs in the system.
+ */
+
+asmlinkage void smp_reboot_interrupt(void)
+{
+ ack_APIC_irq();
+ irq_enter();
+ stop_this_cpu(NULL);
+ irq_exit();
+}
+
+static void native_stop_other_cpus(int wait)
{
unsigned long flags;
unsigned long timeout;
@@ -174,20 +187,25 @@ static void native_nmi_stop_other_cpus(int wait)
* Use an own vector here because smp_call_function
* does lots of things not suitable in a panic situation.
*/
+
+ /*
+ * We start by using the REBOOT_VECTOR irq.
+ * The irq is treated as a sync point to allow critical
+ * regions of code on other cpus to release their spin locks
+ * and re-enable irqs. Jumping straight to an NMI might
+ * accidentally cause deadlocks with further shutdown/panic
+ * code. By syncing, we give the cpus up to one second to
+ * finish their work before we force them off with the NMI.
+ */
if (num_online_cpus() > 1) {
/* did someone beat us here? */
if (atomic_cmpxchg(&stopping_cpu, -1, safe_smp_processor_id()) != -1)
return;
- if (register_nmi_handler(NMI_LOCAL, smp_stop_nmi_callback,
- NMI_FLAG_FIRST, "smp_stop"))
- /* Note: we ignore failures here */
- return;
-
- /* sync above data before sending NMI */
+ /* sync above data before sending IRQ */
wmb();
- apic->send_IPI_allbutself(NMI_VECTOR);
+ apic->send_IPI_allbutself(REBOOT_VECTOR);
/*
* Don't wait longer than a second if the caller
@@ -197,63 +215,37 @@ static void native_nmi_stop_other_cpus(int wait)
while (num_online_cpus() > 1 && (wait || timeout--))
udelay(1);
}
+
+ /* if the REBOOT_VECTOR didn't work, try with the NMI */
+ if ((num_online_cpus() > 1) && (!smp_no_nmi_ipi)) {
+ if (register_nmi_handler(NMI_LOCAL, smp_stop_nmi_callback,
+ NMI_FLAG_FIRST, "smp_stop"))
+ /* Note: we ignore failures here */
+ /* Hope the REBOOT_IRQ is good enough */
+ goto finish;
- local_irq_save(flags);
- disable_local_APIC();
- local_irq_restore(flags);
-}
-
-/*
- * this function calls the 'stop' function on all other CPUs in the system.
- */
-
-asmlinkage void smp_reboot_interrupt(void)
-{
- ack_APIC_irq();
- irq_enter();
- stop_this_cpu(NULL);
- irq_exit();
-}
-
-static void native_irq_stop_other_cpus(int wait)
-{
- unsigned long flags;
- unsigned long timeout;
+ /* sync above data before sending IRQ */
+ wmb();
- if (reboot_force)
- return;
+ pr_emerg("Shutting down cpus with NMI\n");
- /*
- * Use an own vector here because smp_call_function
- * does lots of things not suitable in a panic situation.
- * On most systems we could also use an NMI here,
- * but there are a few systems around where NMI
- * is problematic so stay with an non NMI for now
- * (this implies we cannot stop CPUs spinning with irq off
- * currently)
- */
- if (num_online_cpus() > 1) {
- apic->send_IPI_allbutself(REBOOT_VECTOR);
+ apic->send_IPI_allbutself(NMI_VECTOR);
/*
- * Don't wait longer than a second if the caller
+ * Don't wait longer than a 10 ms if the caller
* didn't ask us to wait.
*/
- timeout = USEC_PER_SEC;
+ timeout = USEC_PER_MSEC * 10;
while (num_online_cpus() > 1 && (wait || timeout--))
udelay(1);
}
+finish:
local_irq_save(flags);
disable_local_APIC();
local_irq_restore(flags);
}
-static void native_smp_disable_nmi_ipi(void)
-{
- smp_ops.stop_other_cpus = native_irq_stop_other_cpus;
-}
-
/*
* Reschedule call back.
*/
@@ -287,8 +279,8 @@ void smp_call_function_single_interrupt(struct pt_regs *regs)
static int __init nonmi_ipi_setup(char *str)
{
- native_smp_disable_nmi_ipi();
- return 1;
+ smp_no_nmi_ipi = true;
+ return 1;
}
__setup("nonmi_ipi", nonmi_ipi_setup);
@@ -298,7 +290,7 @@ struct smp_ops smp_ops = {
.smp_prepare_cpus = native_smp_prepare_cpus,
.smp_cpus_done = native_smp_cpus_done,
- .stop_other_cpus = native_nmi_stop_other_cpus,
+ .stop_other_cpus = native_stop_other_cpus,
.smp_send_reschedule = native_smp_send_reschedule,
.cpu_up = native_cpu_up,
--
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