* Andi Kleen.
*
* CPU hotplug support - ashok.raj@intel.com
- * $Id: process.c,v 1.38 2002/01/15 10:08:03 ak Exp $
*/
/*
#include <linux/ptrace.h>
#include <linux/utsname.h>
#include <linux/random.h>
+#include <linux/notifier.h>
#include <linux/kprobes.h>
#include <asm/uaccess.h>
#include <asm/desc.h>
#include <asm/proto.h>
#include <asm/ia32.h>
+#include <asm/idle.h>
asmlinkage extern void ret_from_fork(void);
unsigned long kernel_thread_flags = CLONE_VM | CLONE_UNTRACED;
-static atomic_t hlt_counter = ATOMIC_INIT(0);
-
unsigned long boot_option_idle_override = 0;
EXPORT_SYMBOL(boot_option_idle_override);
* Powermanagement idle function, if any..
*/
void (*pm_idle)(void);
+EXPORT_SYMBOL(pm_idle);
static DEFINE_PER_CPU(unsigned int, cpu_idle_state);
-void disable_hlt(void)
+static ATOMIC_NOTIFIER_HEAD(idle_notifier);
+
+void idle_notifier_register(struct notifier_block *n)
+{
+ atomic_notifier_chain_register(&idle_notifier, n);
+}
+EXPORT_SYMBOL_GPL(idle_notifier_register);
+
+void idle_notifier_unregister(struct notifier_block *n)
{
- atomic_inc(&hlt_counter);
+ atomic_notifier_chain_unregister(&idle_notifier, n);
}
+EXPORT_SYMBOL(idle_notifier_unregister);
-EXPORT_SYMBOL(disable_hlt);
+enum idle_state { CPU_IDLE, CPU_NOT_IDLE };
+static DEFINE_PER_CPU(enum idle_state, idle_state) = CPU_NOT_IDLE;
-void enable_hlt(void)
+void enter_idle(void)
{
- atomic_dec(&hlt_counter);
+ __get_cpu_var(idle_state) = CPU_IDLE;
+ atomic_notifier_call_chain(&idle_notifier, IDLE_START, NULL);
}
-EXPORT_SYMBOL(enable_hlt);
+static void __exit_idle(void)
+{
+ __get_cpu_var(idle_state) = CPU_NOT_IDLE;
+ atomic_notifier_call_chain(&idle_notifier, IDLE_END, NULL);
+}
+
+/* Called from interrupts to signify idle end */
+void exit_idle(void)
+{
+ if (current->pid | read_pda(irqcount))
+ return;
+ __exit_idle();
+}
/*
* We use this if we don't have any better
* idle routine..
*/
-void default_idle(void)
+static void default_idle(void)
{
local_irq_enable();
- if (!atomic_read(&hlt_counter)) {
- clear_thread_flag(TIF_POLLING_NRFLAG);
- smp_mb__after_clear_bit();
- while (!need_resched()) {
- local_irq_disable();
- if (!need_resched())
- safe_halt();
- else
- local_irq_enable();
- }
- set_thread_flag(TIF_POLLING_NRFLAG);
- } else {
- while (!need_resched())
- cpu_relax();
+ current_thread_info()->status &= ~TS_POLLING;
+ smp_mb__after_clear_bit();
+ while (!need_resched()) {
+ local_irq_disable();
+ if (!need_resched())
+ safe_halt();
+ else
+ local_irq_enable();
}
+ current_thread_info()->status |= TS_POLLING;
}
/*
DECLARE_PER_CPU(int, cpu_state);
#include <asm/nmi.h>
-/* We don't actually take CPU down, just spin without interrupts. */
+/* We halt the CPU with physical CPU hotplug */
static inline void play_dead(void)
{
idle_task_exit();
/* Ack it */
__get_cpu_var(cpu_state) = CPU_DEAD;
+ local_irq_disable();
while (1)
- safe_halt();
+ halt();
}
#else
static inline void play_dead(void)
*/
void cpu_idle (void)
{
- set_thread_flag(TIF_POLLING_NRFLAG);
-
+ current_thread_info()->status |= TS_POLLING;
/* endless idle loop with no priority at all */
while (1) {
while (!need_resched()) {
idle = default_idle;
if (cpu_is_offline(smp_processor_id()))
play_dead();
+ enter_idle();
idle();
+ __exit_idle();
}
preempt_enable_no_resched();
system_utsname.version);
printk("RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->rip);
printk_address(regs->rip);
- printk("\nRSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss, regs->rsp,
+ printk("RSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss, regs->rsp,
regs->eflags);
printk("RAX: %016lx RBX: %016lx RCX: %016lx\n",
regs->rax, regs->rbx, regs->rcx);
{
printk("CPU %d:", smp_processor_id());
__show_regs(regs);
- show_trace(®s->rsp);
+ show_trace(NULL, regs, (void *)(regs + 1));
}
/*
struct task_struct *me = current;
struct thread_struct *t = &me->thread;
- /*
- * Remove function-return probe instances associated with this task
- * and put them back on the free list. Do not insert an exit probe for
- * this function, it will be disabled by kprobe_flush_task if you do.
- */
- kprobe_flush_task(me);
-
if (me->thread.io_bitmap_ptr) {
struct tss_struct *tss = &per_cpu(init_tss, get_cpu());
struct task_struct *tsk = current;
struct thread_info *t = current_thread_info();
- if (t->flags & _TIF_ABI_PENDING)
+ if (t->flags & _TIF_ABI_PENDING) {
t->flags ^= (_TIF_ABI_PENDING | _TIF_IA32);
+ if (t->flags & _TIF_IA32)
+ current_thread_info()->status |= TS_COMPAT;
+ }
tsk->thread.debugreg0 = 0;
tsk->thread.debugreg1 = 0;
struct task_struct *me = current;
childregs = ((struct pt_regs *)
- (THREAD_SIZE + (unsigned long) p->thread_info)) - 1;
+ (THREAD_SIZE + task_stack_page(p))) - 1;
*childregs = *regs;
childregs->rax = 0;
p->thread.rsp0 = (unsigned long) (childregs+1);
p->thread.userrsp = me->thread.userrsp;
- set_ti_thread_flag(p->thread_info, TIF_FORK);
+ set_tsk_thread_flag(p, TIF_FORK);
p->thread.fs = me->thread.fs;
p->thread.gs = me->thread.gs;
/*
* This special macro can be used to load a debugging register
*/
-#define loaddebug(thread,r) set_debug(thread->debugreg ## r, r)
+#define loaddebug(thread,r) set_debugreg(thread->debugreg ## r, r)
/*
* switch_to(x,y) should switch tasks from x to y.
* This could still be optimized:
* - fold all the options into a flag word and test it with a single test.
* - could test fs/gs bitsliced
+ *
+ * Kprobes not supported here. Set the probe on schedule instead.
*/
-struct task_struct *
+__kprobes struct task_struct *
__switch_to(struct task_struct *prev_p, struct task_struct *next_p)
{
struct thread_struct *prev = &prev_p->thread,
int cpu = smp_processor_id();
struct tss_struct *tss = &per_cpu(init_tss, cpu);
- unlazy_fpu(prev_p);
-
/*
* Reload esp0, LDT and the page table pointer:
*/
}
/*
- * Switch the PDA context.
+ * Switch the PDA and FPU contexts.
*/
prev->userrsp = read_pda(oldrsp);
write_pda(oldrsp, next->userrsp);
write_pda(pcurrent, next_p);
+
+ /* This must be here to ensure both math_state_restore() and
+ kernel_fpu_begin() work consistently.
+ And the AMD workaround requires it to be after DS reload. */
+ unlazy_fpu(prev_p);
write_pda(kernelstack,
- (unsigned long)next_p->thread_info + THREAD_SIZE - PDA_STACKOFFSET);
+ task_stack_page(next_p) + THREAD_SIZE - PDA_STACKOFFSET);
/*
* Now maybe reload the debug registers
if (!p || p == current || p->state==TASK_RUNNING)
return 0;
- stack = (unsigned long)p->thread_info;
+ stack = (unsigned long)task_stack_page(p);
if (p->thread.rsp < stack || p->thread.rsp > stack+THREAD_SIZE)
return 0;
fp = *(u64 *)(p->thread.rsp);
}
case ARCH_GET_GS: {
unsigned long base;
+ unsigned gsindex;
if (task->thread.gsindex == GS_TLS_SEL)
base = read_32bit_tls(task, GS_TLS);
- else if (doit)
- rdmsrl(MSR_KERNEL_GS_BASE, base);
+ else if (doit) {
+ asm("movl %%gs,%0" : "=r" (gsindex));
+ if (gsindex)
+ rdmsrl(MSR_KERNEL_GS_BASE, base);
+ else
+ base = task->thread.gs;
+ }
else
base = task->thread.gs;
ret = put_user(base, (unsigned long __user *)addr);
{
struct pt_regs *pp, ptregs;
- pp = (struct pt_regs *)(tsk->thread.rsp0);
- --pp;
+ pp = task_pt_regs(tsk);
ptregs = *pp;
ptregs.cs &= 0xffff;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff