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/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1994 - 2000 by Ralf Baechle and others.
* Copyright (C) 1999 Silicon Graphics, Inc.
*/
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/stddef.h>
#include <linux/unistd.h>
#include <linux/personality.h>
#include <linux/slab.h>
#include <linux/mman.h>
#include <linux/sys.h>
#include <linux/user.h>
#include <linux/a.out.h>
#include <asm/bootinfo.h>
#include <asm/cpu.h>
#include <asm/fpu.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/mipsregs.h>
#include <asm/processor.h>
#include <asm/ptrace.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/elf.h>
#include <asm/isadep.h>
ATTRIB_NORET void cpu_idle(void)
{
/* endless idle loop with no priority at all */
current->nice = 20;
current->counter = -100;
init_idle();
while (1) {
while (!current->need_resched)
if (cpu_wait)
(*cpu_wait)();
schedule();
check_pgt_cache();
}
}
asmlinkage void ret_from_fork(void);
void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp)
{
regs->cp0_status &= ~(ST0_CU0|ST0_KSU|ST0_CU1);
regs->cp0_status |= KU_USER;
current->used_math = 0;
loose_fpu();
regs->cp0_epc = pc;
regs->regs[29] = sp;
current->thread.current_ds = USER_DS;
}
void exit_thread(void)
{
}
void flush_thread(void)
{
}
int copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
unsigned long unused,
struct task_struct * p, struct pt_regs * regs)
{
struct pt_regs * childregs;
long childksp;
childksp = (unsigned long)p + KERNEL_STACK_SIZE - 32;
if (is_fpu_owner()) {
save_fp(p);
}
/* set up new TSS. */
childregs = (struct pt_regs *) childksp - 1;
*childregs = *regs;
childregs->regs[7] = 0; /* Clear error flag */
if(current->personality == PER_LINUX) {
childregs->regs[2] = 0; /* Child gets zero as return value */
regs->regs[2] = p->pid;
} else {
/* Under IRIX things are a little different. */
childregs->regs[2] = 0;
childregs->regs[3] = 1;
regs->regs[2] = p->pid;
regs->regs[3] = 0;
}
if (childregs->cp0_status & ST0_CU0) {
childregs->regs[28] = (unsigned long) p;
childregs->regs[29] = childksp;
p->thread.current_ds = KERNEL_DS;
} else {
childregs->regs[29] = usp;
p->thread.current_ds = USER_DS;
}
p->thread.reg29 = (unsigned long) childregs;
p->thread.reg31 = (unsigned long) ret_from_fork;
/*
* New tasks loose permission to use the fpu. This accelerates context
* switching for most programs since they don't use the fpu.
*/
p->thread.cp0_status = read_c0_status() &
~(ST0_CU2|ST0_CU1|KU_MASK);
childregs->cp0_status &= ~(ST0_CU2|ST0_CU1);
return 0;
}
/* Fill in the fpu structure for a core dump.. */
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *r)
{
memcpy(r, ¤t->thread.fpu, sizeof(current->thread.fpu));
return 1;
}
/*
* Create a kernel thread
*/
int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
{
long retval;
__asm__ __volatile__(
" .set noreorder \n"
" move $6, $sp \n"
" move $4, %5 \n"
" li $2, %1 \n"
" syscall \n"
" beq $6, $sp, 1f \n"
" subu $sp, 32 \n"
" jalr %4 \n"
" move $4, %3 \n"
" move $4, $2 \n"
" li $2, %2 \n"
" syscall \n"
"1: addiu $sp, 32 \n"
" move %0, $2 \n"
" .set reorder"
: "=r" (retval)
: "i" (__NR_clone), "i" (__NR_exit), "r" (arg), "r" (fn),
"r" (flags | CLONE_VM)
/*
* The called subroutine might have destroyed any of the
* at, result, argument or temporary registers ...
*/
: "$2", "$3", "$4", "$5", "$6", "$7", "$8",
"$9","$10","$11","$12","$13","$14","$15","$24","$25", "$31");
return retval;
}
/*
* These bracket the sleeping functions..
*/
extern void scheduling_functions_start_here(void);
extern void scheduling_functions_end_here(void);
#define first_sched ((unsigned long) scheduling_functions_start_here)
#define last_sched ((unsigned long) scheduling_functions_end_here)
/* get_wchan - a maintenance nightmare^W^Wpain in the ass ... */
unsigned long get_wchan(struct task_struct *p)
{
unsigned long frame, pc;
if (!p || p == current || p->state == TASK_RUNNING)
return 0;
pc = thread_saved_pc(&p->thread);
if (pc < first_sched || pc >= last_sched) {
return pc;
}
if (pc >= (unsigned long) sleep_on_timeout)
goto schedule_timeout_caller;
if (pc >= (unsigned long) sleep_on)
goto schedule_caller;
if (pc >= (unsigned long) interruptible_sleep_on_timeout)
goto schedule_timeout_caller;
if (pc >= (unsigned long)interruptible_sleep_on)
goto schedule_caller;
/* Fall through */
schedule_caller:
pc = ((unsigned long *)p->thread.reg30)[13];
return pc;
schedule_timeout_caller:
/*
* The schedule_timeout frame
*/
frame = ((unsigned long *)p->thread.reg30)[13];
/*
* frame now points to sleep_on_timeout's frame
*/
frame = ((unsigned long *)frame)[9];
pc = ((unsigned long *)frame)[10];
if (pc >= first_sched && pc < last_sched) {
/* schedule_timeout called by interruptible_sleep_on_timeout */
frame = ((unsigned long *)frame)[9];
pc = ((unsigned long *)frame)[10];
}
return pc;
}
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