168 lines
3.7 KiB
C
168 lines
3.7 KiB
C
/*
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* linux/arch/cris/kernel/process.c
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*
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* Copyright (C) 1995 Linus Torvalds
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* Copyright (C) 2000-2002 Axis Communications AB
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*
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* Authors: Bjorn Wesen (bjornw@axis.com)
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*
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*/
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/*
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* This file handles the architecture-dependent parts of process handling..
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*/
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#include <asm/atomic.h>
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#include <asm/pgtable.h>
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#include <asm/uaccess.h>
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#include <asm/irq.h>
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#include <asm/system.h>
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#include <linux/module.h>
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#include <linux/spinlock.h>
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#include <linux/fs_struct.h>
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#include <linux/init_task.h>
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#include <linux/sched.h>
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#include <linux/fs.h>
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#include <linux/user.h>
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#include <linux/elfcore.h>
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#include <linux/mqueue.h>
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#include <linux/reboot.h>
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//#define DEBUG
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/*
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* Initial task structure. Make this a per-architecture thing,
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* because different architectures tend to have different
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* alignment requirements and potentially different initial
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* setup.
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*/
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static struct fs_struct init_fs = INIT_FS;
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static struct signal_struct init_signals = INIT_SIGNALS(init_signals);
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static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand);
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struct mm_struct init_mm = INIT_MM(init_mm);
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EXPORT_SYMBOL(init_mm);
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/*
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* Initial thread structure.
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*
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* We need to make sure that this is 8192-byte aligned due to the
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* way process stacks are handled. This is done by having a special
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* "init_task" linker map entry..
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*/
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union thread_union init_thread_union
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__attribute__((__section__(".data.init_task"))) =
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{ INIT_THREAD_INFO(init_task) };
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/*
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* Initial task structure.
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*
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* All other task structs will be allocated on slabs in fork.c
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*/
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struct task_struct init_task = INIT_TASK(init_task);
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EXPORT_SYMBOL(init_task);
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/*
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* The hlt_counter, disable_hlt and enable_hlt is just here as a hook if
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* there would ever be a halt sequence (for power save when idle) with
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* some largish delay when halting or resuming *and* a driver that can't
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* afford that delay. The hlt_counter would then be checked before
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* executing the halt sequence, and the driver marks the unhaltable
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* region by enable_hlt/disable_hlt.
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*/
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int cris_hlt_counter=0;
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void disable_hlt(void)
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{
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cris_hlt_counter++;
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}
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EXPORT_SYMBOL(disable_hlt);
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void enable_hlt(void)
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{
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cris_hlt_counter--;
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}
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EXPORT_SYMBOL(enable_hlt);
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/*
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* The following aren't currently used.
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*/
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void (*pm_idle)(void);
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extern void default_idle(void);
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void (*pm_power_off)(void);
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EXPORT_SYMBOL(pm_power_off);
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/*
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* The idle thread. There's no useful work to be
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* done, so just try to conserve power and have a
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* low exit latency (ie sit in a loop waiting for
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* somebody to say that they'd like to reschedule)
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*/
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void cpu_idle (void)
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{
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/* endless idle loop with no priority at all */
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while (1) {
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while (!need_resched()) {
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void (*idle)(void);
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/*
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* Mark this as an RCU critical section so that
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* synchronize_kernel() in the unload path waits
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* for our completion.
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*/
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idle = pm_idle;
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if (!idle)
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idle = default_idle;
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idle();
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}
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preempt_enable_no_resched();
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schedule();
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preempt_disable();
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}
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}
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void hard_reset_now (void);
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void machine_restart(char *cmd)
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{
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hard_reset_now();
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}
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/*
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* Similar to machine_power_off, but don't shut off power. Add code
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* here to freeze the system for e.g. post-mortem debug purpose when
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* possible. This halt has nothing to do with the idle halt.
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*/
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void machine_halt(void)
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{
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}
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/* If or when software power-off is implemented, add code here. */
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void machine_power_off(void)
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{
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}
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/*
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* When a process does an "exec", machine state like FPU and debug
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* registers need to be reset. This is a hook function for that.
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* Currently we don't have any such state to reset, so this is empty.
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*/
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void flush_thread(void)
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{
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}
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/* Fill in the fpu structure for a core dump. */
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int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
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{
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return 0;
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}
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