diff options
| author | Vineet Gupta <vgupta@synopsys.com> | 2013-07-10 16:03:45 +0200 |
|---|---|---|
| committer | Vineet Gupta <vgupta@synopsys.com> | 2015-02-27 10:15:00 +0530 |
| commit | 3a51d50f426cbb65add424baebe511dcf5ac45cc (patch) | |
| tree | ae5b585e83bd9d4198c8e1307baeb1d9fbad02ac | |
| parent | c517d838eb7d07bbe9507871fab3931deccff539 (diff) | |
| download | linux-3a51d50f426cbb65add424baebe511dcf5ac45cc.tar.bz2 | |
ARC: Make arc_unwind_core accessible externally
The arc unwinder can also be used for perf callchains.
Signed-off-by: Mischa Jonker <mjonker@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
| -rw-r--r-- | arch/arc/include/asm/stacktrace.h | 37 | ||||
| -rw-r--r-- | arch/arc/kernel/stacktrace.c | 15 |
2 files changed, 51 insertions, 1 deletions
diff --git a/arch/arc/include/asm/stacktrace.h b/arch/arc/include/asm/stacktrace.h new file mode 100644 index 000000000000..b29b6064ea14 --- /dev/null +++ b/arch/arc/include/asm/stacktrace.h @@ -0,0 +1,37 @@ +/* + * 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 */ diff --git a/arch/arc/kernel/stacktrace.c b/arch/arc/kernel/stacktrace.c index 9ce47cfe2303..6492507a3d74 100644 --- a/arch/arc/kernel/stacktrace.c +++ b/arch/arc/kernel/stacktrace.c @@ -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) { |