process.c

优龙2410linux2.6.8内核源代码

/*  $Id: process.c,v 1.131 2002/02/09 19:49:30 davem Exp $
 *  arch/sparc64/kernel/process.c
 *
 *  Copyright (C) 1995, 1996 David S. Miller ([e-mail])
 *  Copyright (C) 1996       Eddie C. Dost   ([e-mail])
 *  Copyright (C) 1997, 1998 Jakub Jelinek   ([e-mail])
 */

/*
 * This file handles the architecture-dependent parts of process handling..
 */

#include <stdarg.h>

#include <linux/config.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/kallsyms.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/stddef.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/config.h>
#include <linux/reboot.h>
#include <linux/delay.h>
#include <linux/compat.h>
#include <linux/init.h>

#include <asm/oplib.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/pstate.h>
#include <asm/elf.h>
#include <asm/fpumacro.h>
#include <asm/head.h>
#include <asm/cpudata.h>
#include <asm/unistd.h>

/* #define VERBOSE_SHOWREGS */

/*
 * Nothing special yet...
 */
void default_idle(void)
{
}

#ifndef CONFIG_SMP

/*
 * the idle loop on a Sparc... ;)
 */
int cpu_idle(void)
{
	if (current->pid != 0)
		return -EPERM;

	/* endless idle loop with no priority at all */
	for (;;) {
		/* If current->work.need_resched is zero we should really
		 * setup for a system wakup event and execute a shutdown
		 * instruction.
		 *
		 * But this requires writing back the contents of the
		 * L2 cache etc. so implement this later. -DaveM
		 */
		while (!need_resched())
			barrier();

		schedule();
		check_pgt_cache();
	}
	return 0;
}

#else

/*
 * the idle loop on a UltraMultiPenguin...
 */
#define idle_me_harder()	(cpu_data(smp_processor_id()).idle_volume += 1)
#define unidle_me()		(cpu_data(smp_processor_id()).idle_volume = 0)
int cpu_idle(void)
{
	set_thread_flag(TIF_POLLING_NRFLAG);
	while(1) {
		if (need_resched()) {
			unidle_me();
			clear_thread_flag(TIF_POLLING_NRFLAG);
			schedule();
			set_thread_flag(TIF_POLLING_NRFLAG);
			check_pgt_cache();
		}
		idle_me_harder();

		/* The store ordering is so that IRQ handlers on
		 * other cpus see our increasing idleness for the buddy
		 * redistribution algorithm.  -DaveM
		 */
		membar("#StoreStore | #StoreLoad");
	}
}

#endif

extern char reboot_command [];

extern void (*prom_palette)(int);
extern void (*prom_keyboard)(void);

void machine_halt(void)
{
	if (!serial_console && prom_palette)
		prom_palette (1);
	if (prom_keyboard)
		prom_keyboard();
	prom_halt();
	panic("Halt failed!");
}

EXPORT_SYMBOL(machine_halt);

void machine_alt_power_off(void)
{
	if (!serial_console && prom_palette)
		prom_palette(1);
	if (prom_keyboard)
		prom_keyboard();
	prom_halt_power_off();
	panic("Power-off failed!");
}

void machine_restart(char * cmd)
{
	char *p;
	
	p = strchr (reboot_command, '\n');
	if (p) *p = 0;
	if (!serial_console && prom_palette)
		prom_palette (1);
	if (prom_keyboard)
		prom_keyboard();
	if (cmd)
		prom_reboot(cmd);
	if (*reboot_command)
		prom_reboot(reboot_command);
	prom_reboot("");
	panic("Reboot failed!");
}

EXPORT_SYMBOL(machine_restart);

static void show_regwindow32(struct pt_regs *regs)
{
	struct reg_window32 __user *rw;
	struct reg_window32 r_w;
	mm_segment_t old_fs;
	
	__asm__ __volatile__ ("flushw");
	rw = (struct reg_window32 __user *)((long)(unsigned)regs->u_regs[14]);
	old_fs = get_fs();
	set_fs (USER_DS);
	if (copy_from_user (&r_w, rw, sizeof(r_w))) {
		set_fs (old_fs);
		return;
	}

	set_fs (old_fs);			
	printk("l0: %08x l1: %08x l2: %08x l3: %08x "
	       "l4: %08x l5: %08x l6: %08x l7: %08x\n",
	       r_w.locals[0], r_w.locals[1], r_w.locals[2], r_w.locals[3],
	       r_w.locals[4], r_w.locals[5], r_w.locals[6], r_w.locals[7]);
	printk("i0: %08x i1: %08x i2: %08x i3: %08x "
	       "i4: %08x i5: %08x i6: %08x i7: %08x\n",
	       r_w.ins[0], r_w.ins[1], r_w.ins[2], r_w.ins[3],
	       r_w.ins[4], r_w.ins[5], r_w.ins[6], r_w.ins[7]);
}

static void show_regwindow(struct pt_regs *regs)
{
	struct reg_window __user *rw;
	struct reg_window *rwk;
	struct reg_window r_w;
	mm_segment_t old_fs;

	if ((regs->tstate & TSTATE_PRIV) || !(test_thread_flag(TIF_32BIT))) {
		__asm__ __volatile__ ("flushw");
		rw = (struct reg_window __user *)
			(regs->u_regs[14] + STACK_BIAS);
		rwk = (struct reg_window *)
			(regs->u_regs[14] + STACK_BIAS);
		if (!(regs->tstate & TSTATE_PRIV)) {
			old_fs = get_fs();
			set_fs (USER_DS);
			if (copy_from_user (&r_w, rw, sizeof(r_w))) {
				set_fs (old_fs);
				return;
			}
			rwk = &r_w;
			set_fs (old_fs);			
		}
	} else {
		show_regwindow32(regs);
		return;
	}
	printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
	       rwk->locals[0], rwk->locals[1], rwk->locals[2], rwk->locals[3]);
	printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
	       rwk->locals[4], rwk->locals[5], rwk->locals[6], rwk->locals[7]);
	printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
	       rwk->ins[0], rwk->ins[1], rwk->ins[2], rwk->ins[3]);
	printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
	       rwk->ins[4], rwk->ins[5], rwk->ins[6], rwk->ins[7]);
	if (regs->tstate & TSTATE_PRIV)
		print_symbol("I7: <%s>\n", rwk->ins[7]);
}

void show_stackframe(struct sparc_stackf *sf)
{
	unsigned long size;
	unsigned long *stk;
	int i;

	printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n"
	       "l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
	       sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3],
	       sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
	printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n"
	       "i4: %016lx i5: %016lx fp: %016lx ret_pc: %016lx\n",
	       sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3],
	       sf->ins[4], sf->ins[5], (unsigned long)sf->fp, sf->callers_pc);
	printk("sp: %016lx x0: %016lx x1: %016lx x2: %016lx\n"
	       "x3: %016lx x4: %016lx x5: %016lx xx: %016lx\n",
	       (unsigned long)sf->structptr, sf->xargs[0], sf->xargs[1],
	       sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
	       sf->xxargs[0]);
	size = ((unsigned long)sf->fp) - ((unsigned long)sf);
	size -= STACKFRAME_SZ;
	stk = (unsigned long *)((unsigned long)sf + STACKFRAME_SZ);
	i = 0;
	do {
		printk("s%d: %016lx\n", i++, *stk++);
	} while ((size -= sizeof(unsigned long)));
}

void show_stackframe32(struct sparc_stackf32 *sf)
{
	unsigned long size;
	unsigned *stk;
	int i;

	printk("l0: %08x l1: %08x l2: %08x l3: %08x\n",
	       sf->locals[0], sf->locals[1], sf->locals[2], sf->locals[3]);
	printk("l4: %08x l5: %08x l6: %08x l7: %08x\n",
	       sf->locals[4], sf->locals[5], sf->locals[6], sf->locals[7]);
	printk("i0: %08x i1: %08x i2: %08x i3: %08x\n",
	       sf->ins[0], sf->ins[1], sf->ins[2], sf->ins[3]);
	printk("i4: %08x i5: %08x fp: %08x ret_pc: %08x\n",
	       sf->ins[4], sf->ins[5], sf->fp, sf->callers_pc);
	printk("sp: %08x x0: %08x x1: %08x x2: %08x\n"
	       "x3: %08x x4: %08x x5: %08x xx: %08x\n",
	       sf->structptr, sf->xargs[0], sf->xargs[1],
	       sf->xargs[2], sf->xargs[3], sf->xargs[4], sf->xargs[5],
	       sf->xxargs[0]);
	size = ((unsigned long)sf->fp) - ((unsigned long)sf);
	size -= STACKFRAME32_SZ;
	stk = (unsigned *)((unsigned long)sf + STACKFRAME32_SZ);
	i = 0;
	do {
		printk("s%d: %08x\n", i++, *stk++);
	} while ((size -= sizeof(unsigned)));
}

#ifdef CONFIG_SMP
static spinlock_t regdump_lock = SPIN_LOCK_UNLOCKED;
#endif

void __show_regs(struct pt_regs * regs)
{
#ifdef CONFIG_SMP
	unsigned long flags;

	/* Protect against xcall ipis which might lead to livelock on the lock */
	__asm__ __volatile__("rdpr      %%pstate, %0\n\t"
			     "wrpr      %0, %1, %%pstate"
			     : "=r" (flags)
			     : "i" (PSTATE_IE));
	spin_lock(&regdump_lock);
#endif
	printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x    %s\n", regs->tstate,
	       regs->tpc, regs->tnpc, regs->y, print_tainted());
	print_symbol("TPC: <%s>\n", regs->tpc);
	printk("g0: %016lx g1: %016lx g2: %016lx g3: %016lx\n",
	       regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
	       regs->u_regs[3]);
	printk("g4: %016lx g5: %016lx g6: %016lx g7: %016lx\n",
	       regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
	       regs->u_regs[7]);
	printk("o0: %016lx o1: %016lx o2: %016lx o3: %016lx\n",
	       regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
	       regs->u_regs[11]);
	printk("o4: %016lx o5: %016lx sp: %016lx ret_pc: %016lx\n",
	       regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
	       regs->u_regs[15]);
	print_symbol("RPC: <%s>\n", regs->u_regs[15]);
	show_regwindow(regs);
#ifdef CONFIG_SMP
	spin_unlock(&regdump_lock);
	__asm__ __volatile__("wrpr	%0, 0, %%pstate"
			     : : "r" (flags));
#endif
}

#ifdef VERBOSE_SHOWREGS
static void idump_from_user (unsigned int *pc)
{
	int i;
	int code;
	
	if((((unsigned long) pc) & 3))
		return;
	
	pc -= 3;
	for(i = -3; i < 6; i++) {
		get_user(code, pc);
		printk("%c%08x%c",i?' ':'<',code,i?' ':'>');
		pc++;
	}
	printk("\n");
}
#endif

void show_regs(struct pt_regs *regs)
{
#ifdef VERBOSE_SHOWREGS
	extern long etrap, etraptl1;
#endif
	__show_regs(regs);
#ifdef CONFIG_SMP
	{
		extern void smp_report_regs(void);

		smp_report_regs();
	}
#endif

#ifdef VERBOSE_SHOWREGS	
	if (regs->tpc >= &etrap && regs->tpc < &etraptl1 &&
	    regs->u_regs[14] >= (long)current - PAGE_SIZE &&
	    regs->u_regs[14] < (long)current + 6 * PAGE_SIZE) {
		printk ("*********parent**********\n");
		__show_regs((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF));
		idump_from_user(((struct pt_regs *)(regs->u_regs[14] + PTREGS_OFF))->tpc);
		printk ("*********endpar**********\n");
	}
#endif
}

void show_regs32(struct pt_regs32 *regs)
{
	printk("PSR: %08x PC: %08x NPC: %08x Y: %08x    %s\n", regs->psr,
	       regs->pc, regs->npc, regs->y, print_tainted());
	printk("g0: %08x g1: %08x g2: %08x g3: %08x ",
	       regs->u_regs[0], regs->u_regs[1], regs->u_regs[2],
	       regs->u_regs[3]);
	printk("g4: %08x g5: %08x g6: %08x g7: %08x\n",
	       regs->u_regs[4], regs->u_regs[5], regs->u_regs[6],
	       regs->u_regs[7]);
	printk("o0: %08x o1: %08x o2: %08x o3: %08x ",
	       regs->u_regs[8], regs->u_regs[9], regs->u_regs[10],
	       regs->u_regs[11]);
	printk("o4: %08x o5: %08x sp: %08x ret_pc: %08x\n",
	       regs->u_regs[12], regs->u_regs[13], regs->u_regs[14],
	       regs->u_regs[15]);
}

unsigned long thread_saved_pc(struct task_struct *tsk)
{
	struct thread_info *ti = tsk->thread_info;
	unsigned long ret = 0xdeadbeefUL;
	
	if (ti && ti->ksp) {
		unsigned long *sp;
		sp = (unsigned long *)(ti->ksp + STACK_BIAS);
		if (((unsigned long)sp & (sizeof(long) - 1)) == 0UL &&
		    sp[14]) {
			unsigned long *fp;
			fp = (unsigned long *)(sp[14] + STACK_BIAS);
			if (((unsigned long)fp & (sizeof(long) - 1)) == 0UL)
				ret = fp[15];
		}
	}
	return ret;
}

/* Free current thread data structures etc.. */
void exit_thread(void)
{
	struct thread_info *t = current_thread_info();

	if (t->utraps) {
		if (t->utraps[0] < 2)
			kfree (t->utraps);
		else
			t->utraps[0]--;
	}

	if (test_and_clear_thread_flag(TIF_PERFCTR)) {
		t->user_cntd0 = t->user_cntd1 = NULL;
		t->pcr_reg = 0;
		write_pcr(0);
	}
}

void flush_thread(void)
{
	struct thread_info *t = current_thread_info();

	if (t->flags & _TIF_ABI_PENDING)
		t->flags ^= (_TIF_ABI_PENDING | _TIF_32BIT);

	if (t->task->mm) {
		unsigned long pgd_cache = 0UL;
		if (test_thread_flag(TIF_32BIT)) {
			struct mm_struct *mm = t->task->mm;
			pgd_t *pgd0 = &mm->pgd[0];