process.c

Linux内核源代码 为压缩文件 是<<Linux内核>>一书中的源代码

/*  $Id: process.c,v 1.113 2000/11/08 08:14:58 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..
 */

#define __KERNEL_SYSCALLS__
#include <stdarg.h>

#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/ptrace.h>
#include <linux/malloc.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <linux/config.h>
#include <linux/reboot.h>
#include <linux/delay.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>

/* #define VERBOSE_SHOWREGS */

#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 */
	current->nice = 20;
	current->counter = -100;
	init_idle();

	for (;;) {
		/* If current->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 (!current->need_resched)
			barrier();

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

#else

/*
 * the idle loop on a UltraMultiPenguin...
 */
#define idle_me_harder()	(cpu_data[current->processor].idle_volume += 1)
#define unidle_me()		(cpu_data[current->processor].idle_volume = 0)
int cpu_idle(void)
{
	current->nice = 20;
	current->counter = -100;
	init_idle();

	while(1) {
		if (current->need_resched != 0) {
			unidle_me();
			schedule();
			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 [];

#ifdef CONFIG_SUN_CONSOLE
extern void (*prom_palette)(int);
extern int serial_console;
#endif

void machine_halt(void)
{
	sti();
	mdelay(8);
	cli();
#ifdef CONFIG_SUN_CONSOLE
	if (!serial_console && prom_palette)
		prom_palette (1);
#endif
	prom_halt();
	panic("Halt failed!");
}

void machine_restart(char * cmd)
{
	char *p;
	
	sti();
	mdelay(8);
	cli();

	p = strchr (reboot_command, '\n');
	if (p) *p = 0;
#ifdef CONFIG_SUN_CONSOLE
	if (!serial_console && prom_palette)
		prom_palette (1);
#endif
	if (cmd)
		prom_reboot(cmd);
	if (*reboot_command)
		prom_reboot(reboot_command);
	prom_reboot("");
	panic("Reboot failed!");
}

static void show_regwindow32(struct pt_regs *regs)
{
	struct reg_window32 *rw;
	struct reg_window32 r_w;
	mm_segment_t old_fs;
	
	__asm__ __volatile__ ("flushw");
	rw = (struct reg_window32 *)((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;
	}
	rw = &r_w;
	set_fs (old_fs);			
	printk("l0: %08x l1: %08x l2: %08x l3: %08x "
	       "l4: %08x l5: %08x l6: %08x l7: %08x\n",
	       rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3],
	       rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]);
	printk("i0: %08x i1: %08x i2: %08x i3: %08x "
	       "i4: %08x i5: %08x i6: %08x i7: %08x\n",
	       rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3],
	       rw->ins[4], rw->ins[5], rw->ins[6], rw->ins[7]);
}

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

	if ((regs->tstate & TSTATE_PRIV) || !(current->thread.flags & SPARC_FLAG_32BIT)) {
		__asm__ __volatile__ ("flushw");
		rw = (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;
			}
			rw = &r_w;
			set_fs (old_fs);			
		}
	} else {
		show_regwindow32(regs);
		return;
	}
	printk("l0: %016lx l1: %016lx l2: %016lx l3: %016lx\n",
	       rw->locals[0], rw->locals[1], rw->locals[2], rw->locals[3]);
	printk("l4: %016lx l5: %016lx l6: %016lx l7: %016lx\n",
	       rw->locals[4], rw->locals[5], rw->locals[6], rw->locals[7]);
	printk("i0: %016lx i1: %016lx i2: %016lx i3: %016lx\n",
	       rw->ins[0], rw->ins[1], rw->ins[2], rw->ins[3]);
	printk("i4: %016lx i5: %016lx i6: %016lx i7: %016lx\n",
	       rw->ins[4], rw->ins[5], rw->ins[6], rw->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;

	spin_lock_irqsave(&regdump_lock, flags);
	printk("CPU[%d]: local_irq_count[%u] irqs_running[%d]\n",
	       smp_processor_id(),
	       local_irq_count(smp_processor_id()),
	       irqs_running());
#endif
	printk("TSTATE: %016lx TPC: %016lx TNPC: %016lx Y: %08x\n", regs->tstate,
	       regs->tpc, regs->tnpc, regs->y);
	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]);
	show_regwindow(regs);
#ifdef CONFIG_SMP
	spin_unlock_irqrestore(&regdump_lock, 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] + STACK_BIAS + REGWIN_SZ));
		idump_from_user(((struct pt_regs *)(regs->u_regs[14] + STACK_BIAS + REGWIN_SZ))->tpc);
		printk ("*********endpar**********\n");
	}
#endif
}

void show_regs32(struct pt_regs32 *regs)
{
	printk("PSR: %08x PC: %08x NPC: %08x Y: %08x\n", regs->psr,
	       regs->pc, regs->npc, regs->y);
	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]);
}

void show_thread(struct thread_struct *thread)
{
	int i;

#if 0
	printk("kregs:             0x%016lx\n", (unsigned long)thread->kregs);
	show_regs(thread->kregs);
#endif	
	printk("ksp:               0x%016lx\n", thread->ksp);

	if (thread->w_saved) {
		for (i = 0; i < NSWINS; i++) {
			if (!thread->rwbuf_stkptrs[i])
				continue;
			printk("reg_window[%d]:\n", i);
			printk("stack ptr:         0x%016lx\n", thread->rwbuf_stkptrs[i]);
		}
		printk("w_saved:           0x%04x\n", thread->w_saved);
	}

	printk("flags:             0x%08x\n", thread->flags);
	printk("current_ds:        0x%x\n", thread->current_ds.seg);
}

/* Free current thread data structures etc.. */
void exit_thread(void)
{
	struct thread_struct *t = &current->thread;

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

	/* Turn off performance counters if on. */
	if (t->flags & SPARC_FLAG_PERFCTR) {
		t->user_cntd0 = t->user_cntd1 = NULL;
		t->pcr_reg = 0;
		t->flags &= ~(SPARC_FLAG_PERFCTR);