Commit 3a51d50f authored by Vineet Gupta's avatar Vineet Gupta
Browse files

ARC: Make arc_unwind_core accessible externally 



The arc unwinder can also be used for perf callchains.

Signed-off-by: default avatarMischa Jonker <mjonker@synopsys.com>
Signed-off-by: default avatarVineet Gupta <vgupta@synopsys.com>
parent c517d838

arch/arc/include/asm/stacktrace.h

0 → 100644
+37 −0
Original line number Diff line number Diff line 
/*

 * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)

 * Copyright (C) 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */



#ifndef __ASM_STACKTRACE_H

#define __ASM_STACKTRACE_H



#include <linux/sched.h>



/**

 * arc_unwind_core - Unwind the kernel mode stack for an execution context

 * @tsk:		NULL for current task, specific task otherwise

 * @regs:		pt_regs used to seed the unwinder {SP, FP, BLINK, PC}

 * 			If NULL, use pt_regs of @tsk (if !NULL) otherwise

 * 			use the current values of {SP, FP, BLINK, PC}

 * @consumer_fn:	Callback invoked for each frame unwound

 * 			Returns 0 to continue unwinding, -1 to stop

 * @arg:		Arg to callback

 *

 * Returns the address of first function in stack

 *

 * Semantics:

 *  - synchronous unwinding (e.g. dump_stack): @tsk  NULL, @regs  NULL

 *  - Asynchronous unwinding of sleeping task: @tsk !NULL, @regs  NULL

 *  - Asynchronous unwinding of intr/excp etc: @tsk !NULL, @regs !NULL

 */

notrace noinline unsigned int arc_unwind_core(

	struct task_struct *tsk, struct pt_regs *regs,

	int (*consumer_fn) (unsigned int, void *),

	void *arg);



#endif /* __ASM_STACKTRACE_H */

arch/arc/kernel/stacktrace.c

+14 −1
Original line number Diff line number Diff line
@@ -43,6 +43,10 @@ static void seed_unwind_frame_info(struct task_struct *tsk, 
				   struct pt_regs *regs,

				   struct unwind_frame_info *frame_info)

{

	/*

	 * synchronous unwinding (e.g. dump_stack)

	 *  - uses current values of SP and friends

	 */

	if (tsk == NULL && regs == NULL) {

		unsigned long fp, sp, blink, ret;

		frame_info->task = current;
@@ -61,6 +65,11 @@ static void seed_unwind_frame_info(struct task_struct *tsk, 
		frame_info->regs.r63 = ret;

		frame_info->call_frame = 0;

	} else if (regs == NULL) {

		/*

		 * Asynchronous unwinding of sleeping task

		 *  - Gets SP etc from task's pt_regs (saved bottom of kernel

		 *    mode stack of task)

		 */



		frame_info->task = tsk;
@@ -83,6 +92,10 @@ static void seed_unwind_frame_info(struct task_struct *tsk, 
		frame_info->call_frame = 0;



	} else {

		/*

		 * Asynchronous unwinding of intr/exception

		 *  - Just uses the pt_regs passed

		 */

		frame_info->task = tsk;



		frame_info->regs.r27 = regs->fp;
@@ -95,7 +108,7 @@ static void seed_unwind_frame_info(struct task_struct *tsk, 


#endif



static noinline unsigned int

notrace noinline unsigned int

arc_unwind_core(struct task_struct *tsk, struct pt_regs *regs,

		int (*consumer_fn) (unsigned int, void *), void *arg)

{