From 3a51d50f426cbb65add424baebe511dcf5ac45cc Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Wed, 10 Jul 2013 16:03:45 +0200 Subject: ARC: Make arc_unwind_core accessible externally The arc unwinder can also be used for perf callchains. Signed-off-by: Mischa Jonker Signed-off-by: Vineet Gupta --- arch/arc/include/asm/stacktrace.h | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 arch/arc/include/asm/stacktrace.h (limited to 'arch/arc/include/asm') 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 + +/** + * 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 */ -- cgit v1.2.1 From 13648b0118a24f4fc76c34e6c7b6ccf447e46a2a Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Fri, 27 Feb 2015 10:39:17 +0530 Subject: ARC: Fix KSTK_ESP() /proc//maps currently don't annotate stack vma with "[stack]" This is because KSTK_ESP ie expected to return usermode SP of tsk while currently it returns the kernel mode SP of a sleeping tsk. While the fix is trivial, we also need to adjust the ARC kernel stack unwinder to not use KSTK_SP and friends any more. Cc: Reported-and-suggested-by: Alexey Brodkin Signed-off-by: Vineet Gupta --- arch/arc/include/asm/processor.h | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'arch/arc/include/asm') diff --git a/arch/arc/include/asm/processor.h b/arch/arc/include/asm/processor.h index 4e547296831d..88398caa3989 100644 --- a/arch/arc/include/asm/processor.h +++ b/arch/arc/include/asm/processor.h @@ -72,18 +72,19 @@ unsigned long thread_saved_pc(struct task_struct *t); #define release_segments(mm) do { } while (0) #define KSTK_EIP(tsk) (task_pt_regs(tsk)->ret) +#define KSTK_ESP(tsk) (task_pt_regs(tsk)->sp) /* * Where abouts of Task's sp, fp, blink when it was last seen in kernel mode. * Look in process.c for details of kernel stack layout */ -#define KSTK_ESP(tsk) (tsk->thread.ksp) +#define TSK_K_ESP(tsk) (tsk->thread.ksp) -#define KSTK_REG(tsk, off) (*((unsigned int *)(KSTK_ESP(tsk) + \ +#define TSK_K_REG(tsk, off) (*((unsigned int *)(TSK_K_ESP(tsk) + \ sizeof(struct callee_regs) + off))) -#define KSTK_BLINK(tsk) KSTK_REG(tsk, 4) -#define KSTK_FP(tsk) KSTK_REG(tsk, 0) +#define TSK_K_BLINK(tsk) TSK_K_REG(tsk, 4) +#define TSK_K_FP(tsk) TSK_K_REG(tsk, 0) extern void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long usp); -- cgit v1.2.1 From 3240dd57e533da94998029af6e17008a1806c665 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Fri, 27 Feb 2015 10:59:31 +0530 Subject: ARC: Fix thread_saved_pc() The old implementation assumed that SP at the time of __switch_to() is right above pt_regs which is almost certainly not the case as there will be some stack build up between entry into kernel and leading up to __switch_to Signed-off-by: Vineet Gupta --- arch/arc/include/asm/processor.h | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'arch/arc/include/asm') diff --git a/arch/arc/include/asm/processor.h b/arch/arc/include/asm/processor.h index 88398caa3989..52312cb5dbe2 100644 --- a/arch/arc/include/asm/processor.h +++ b/arch/arc/include/asm/processor.h @@ -47,9 +47,6 @@ struct thread_struct { /* Forward declaration, a strange C thing */ struct task_struct; -/* Return saved PC of a blocked thread */ -unsigned long thread_saved_pc(struct task_struct *t); - #define task_pt_regs(p) \ ((struct pt_regs *)(THREAD_SIZE + (void *)task_stack_page(p)) - 1) @@ -86,6 +83,8 @@ unsigned long thread_saved_pc(struct task_struct *t); #define TSK_K_BLINK(tsk) TSK_K_REG(tsk, 4) #define TSK_K_FP(tsk) TSK_K_REG(tsk, 0) +#define thread_saved_pc(tsk) TSK_K_BLINK(tsk) + extern void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long usp); -- cgit v1.2.1