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