diff options
Diffstat (limited to 'arch/um/kernel/process.c')
| -rw-r--r-- | arch/um/kernel/process.c | 114 | 
1 files changed, 33 insertions, 81 deletions
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c index fab4371184f..f17bca8ed2c 100644 --- a/arch/um/kernel/process.c +++ b/arch/um/kernel/process.c @@ -18,14 +18,15 @@  #include <linux/seq_file.h>  #include <linux/tick.h>  #include <linux/threads.h> +#include <linux/tracehook.h>  #include <asm/current.h>  #include <asm/pgtable.h> +#include <asm/mmu_context.h>  #include <asm/uaccess.h> -#include "as-layout.h" -#include "kern_util.h" -#include "os.h" -#include "skas.h" -#include "tlb.h" +#include <as-layout.h> +#include <kern_util.h> +#include <os.h> +#include <skas.h>  /*   * This is a per-cpu array.  A processor only modifies its entry and it only @@ -68,17 +69,6 @@ unsigned long alloc_stack(int order, int atomic)  	return page;  } -int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) -{ -	int pid; - -	current->thread.request.u.thread.proc = fn; -	current->thread.request.u.thread.arg = arg; -	pid = do_fork(CLONE_VM | CLONE_UNTRACED | flags, 0, -		      ¤t->thread.regs, 0, NULL, NULL); -	return pid; -} -  static inline void set_current(struct task_struct *task)  {  	cpu_tasks[task_thread_info(task)->cpu] = ((struct cpu_task) @@ -87,47 +77,34 @@ static inline void set_current(struct task_struct *task)  extern void arch_switch_to(struct task_struct *to); -void *_switch_to(void *prev, void *next, void *last) +void *__switch_to(struct task_struct *from, struct task_struct *to)  { -	struct task_struct *from = prev; -	struct task_struct *to = next; -  	to->thread.prev_sched = from;  	set_current(to); -	do { -		current->thread.saved_task = NULL; - -		switch_threads(&from->thread.switch_buf, -			       &to->thread.switch_buf); - -		arch_switch_to(current); - -		if (current->thread.saved_task) -			show_regs(&(current->thread.regs)); -		to = current->thread.saved_task; -		from = current; -	} while (current->thread.saved_task); +	switch_threads(&from->thread.switch_buf, &to->thread.switch_buf); +	arch_switch_to(current);  	return current->thread.prev_sched; -  }  void interrupt_end(void)  {  	if (need_resched())  		schedule(); -	if (test_tsk_thread_flag(current, TIF_SIGPENDING)) +	if (test_thread_flag(TIF_SIGPENDING))  		do_signal(); +	if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) +		tracehook_notify_resume(¤t->thread.regs);  }  void exit_thread(void)  {  } -void *get_current(void) +int get_current_pid(void)  { -	return current; +	return task_pid_nr(current);  }  /* @@ -147,16 +124,10 @@ void new_thread_handler(void)  	arg = current->thread.request.u.thread.arg;  	/* -	 * The return value is 1 if the kernel thread execs a process, -	 * 0 if it just exits +	 * callback returns only if the kernel thread execs a process  	 */ -	n = run_kernel_thread(fn, arg, ¤t->thread.exec_buf); -	if (n == 1) { -		/* Handle any immediate reschedules or signals */ -		interrupt_end(); -		userspace(¤t->thread.regs.regs); -	} -	else do_exit(0); +	n = fn(arg); +	userspace(¤t->thread.regs.regs);  }  /* Called magically, see new_thread_handler above */ @@ -175,41 +146,38 @@ void fork_handler(void)  	current->thread.prev_sched = NULL; -	/* Handle any immediate reschedules or signals */ -	interrupt_end(); -  	userspace(¤t->thread.regs.regs);  }  int copy_thread(unsigned long clone_flags, unsigned long sp, -		unsigned long stack_top, struct task_struct * p, -		struct pt_regs *regs) +		unsigned long arg, struct task_struct * p)  {  	void (*handler)(void); +	int kthread = current->flags & PF_KTHREAD;  	int ret = 0;  	p->thread = (struct thread_struct) INIT_THREAD; -	if (current->thread.forking) { -	  	memcpy(&p->thread.regs.regs, ®s->regs, +	if (!kthread) { +	  	memcpy(&p->thread.regs.regs, current_pt_regs(),  		       sizeof(p->thread.regs.regs)); -		REGS_SET_SYSCALL_RETURN(p->thread.regs.regs.gp, 0); +		PT_REGS_SET_SYSCALL_RETURN(&p->thread.regs, 0);  		if (sp != 0)  			REGS_SP(p->thread.regs.regs.gp) = sp;  		handler = fork_handler;  		arch_copy_thread(¤t->thread.arch, &p->thread.arch); -	} -	else { -		get_safe_registers(p->thread.regs.regs.gp); -		p->thread.request.u.thread = current->thread.request.u.thread; +	} else { +		get_safe_registers(p->thread.regs.regs.gp, p->thread.regs.regs.fp); +		p->thread.request.u.thread.proc = (int (*)(void *))sp; +		p->thread.request.u.thread.arg = (void *)arg;  		handler = new_thread_handler;  	}  	new_thread(task_stack_page(p), &p->thread.switch_buf, handler); -	if (current->thread.forking) { +	if (!kthread) {  		clear_flushed_tls(p);  		/* @@ -231,31 +199,14 @@ void initial_thread_cb(void (*proc)(void *), void *arg)  	kmalloc_ok = save_kmalloc_ok;  } -void default_idle(void) +void arch_cpu_idle(void)  {  	unsigned long long nsecs; -	while (1) { -		/* endless idle loop with no priority at all */ - -		/* -		 * although we are an idle CPU, we do not want to -		 * get into the scheduler unnecessarily. -		 */ -		if (need_resched()) -			schedule(); - -		tick_nohz_stop_sched_tick(1); -		nsecs = disable_timer(); -		idle_sleep(nsecs); -		tick_nohz_restart_sched_tick(); -	} -} - -void cpu_idle(void) -{  	cpu_tasks[current_thread_info()->cpu].pid = os_getpid(); -	default_idle(); +	nsecs = disable_timer(); +	idle_sleep(nsecs); +	local_irq_enable();  }  int __cant_sleep(void) { @@ -286,6 +237,7 @@ char *uml_strdup(const char *string)  {  	return kstrdup(string, GFP_KERNEL);  } +EXPORT_SYMBOL(uml_strdup);  int copy_to_user_proc(void __user *to, void *from, int size)  { @@ -407,7 +359,7 @@ int singlestepping(void * t)  /*   * Only x86 and x86_64 have an arch_align_stack().   * All other arches have "#define arch_align_stack(x) (x)" - * in their asm/system.h + * in their asm/exec.h   * As this is included in UML from asm-um/system-generic.h,   * we can use it to behave as the subarch does.   */  | 
