forked from mirrors/linux
		
	 b17b01533b
			
		
	
	
		b17b01533b
		
	
	
	
	
		
			
			We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/debug.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
		
			
				
	
	
		
			65 lines
		
	
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			65 lines
		
	
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * Provide a default dump_stack() function for architectures
 | |
|  * which don't implement their own.
 | |
|  */
 | |
| 
 | |
| #include <linux/kernel.h>
 | |
| #include <linux/export.h>
 | |
| #include <linux/sched.h>
 | |
| #include <linux/sched/debug.h>
 | |
| #include <linux/smp.h>
 | |
| #include <linux/atomic.h>
 | |
| 
 | |
| static void __dump_stack(void)
 | |
| {
 | |
| 	dump_stack_print_info(KERN_DEFAULT);
 | |
| 	show_stack(NULL, NULL);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * dump_stack - dump the current task information and its stack trace
 | |
|  *
 | |
|  * Architectures can override this implementation by implementing its own.
 | |
|  */
 | |
| #ifdef CONFIG_SMP
 | |
| static atomic_t dump_lock = ATOMIC_INIT(-1);
 | |
| 
 | |
| asmlinkage __visible void dump_stack(void)
 | |
| {
 | |
| 	unsigned long flags;
 | |
| 	int was_locked;
 | |
| 	int old;
 | |
| 	int cpu;
 | |
| 
 | |
| 	/*
 | |
| 	 * Permit this cpu to perform nested stack dumps while serialising
 | |
| 	 * against other CPUs
 | |
| 	 */
 | |
| retry:
 | |
| 	local_irq_save(flags);
 | |
| 	cpu = smp_processor_id();
 | |
| 	old = atomic_cmpxchg(&dump_lock, -1, cpu);
 | |
| 	if (old == -1) {
 | |
| 		was_locked = 0;
 | |
| 	} else if (old == cpu) {
 | |
| 		was_locked = 1;
 | |
| 	} else {
 | |
| 		local_irq_restore(flags);
 | |
| 		cpu_relax();
 | |
| 		goto retry;
 | |
| 	}
 | |
| 
 | |
| 	__dump_stack();
 | |
| 
 | |
| 	if (!was_locked)
 | |
| 		atomic_set(&dump_lock, -1);
 | |
| 
 | |
| 	local_irq_restore(flags);
 | |
| }
 | |
| #else
 | |
| asmlinkage __visible void dump_stack(void)
 | |
| {
 | |
| 	__dump_stack();
 | |
| }
 | |
| #endif
 | |
| EXPORT_SYMBOL(dump_stack);
 |