diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-09 14:38:16 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-09 14:38:16 -0700 |
commit | c61c48dfe00907007df3b87e4ed271a5c143bdda (patch) | |
tree | 6d26bd3a8b4aa3cf35cad35fa27d1e0afe715db3 /arch/xtensa/kernel/stacktrace.c | |
parent | e30f4192456971623b40c97a027346b69457ef69 (diff) | |
parent | b341d84c8ac5ecbf7aa0b3ccd0745d87e881953c (diff) |
Merge tag 'xtensa-next-20130508' of git://github.com/czankel/xtensa-linux
Pull xtensa updates from Chris Zankel:
"Support for the latest MMU architecture that allows for a larger
accessible memory region, and various bug-fixes"
* tag 'xtensa-next-20130508' of git://github.com/czankel/xtensa-linux:
xtensa: Switch to asm-generic/linkage.h
xtensa: fix redboot load address
xtensa: ISS: fix timer_lock usage in rs_open
xtensa: disable IRQs while IRQ handler is running
xtensa: enable lockdep support
xtensa: fix arch_irqs_disabled_flags implementation
xtensa: add irq flags trace support
xtensa: provide custom CALLER_ADDR* implementations
xtensa: add stacktrace support
xtensa: clean up stpill_registers
xtensa: don't use a7 in simcalls
xtensa: don't attempt to use unconfigured timers
xtensa: provide default platform_pcibios_init implementation
xtensa: remove KCORE_ELF again
xtensa: document MMUv3 setup sequence
xtensa: add MMU v3 support
xtensa: fix ibreakenable register update
xtensa: fix oprofile building as module
Diffstat (limited to 'arch/xtensa/kernel/stacktrace.c')
-rw-r--r-- | arch/xtensa/kernel/stacktrace.c | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/arch/xtensa/kernel/stacktrace.c b/arch/xtensa/kernel/stacktrace.c new file mode 100644 index 000000000000..7d2c317bd98b --- /dev/null +++ b/arch/xtensa/kernel/stacktrace.c @@ -0,0 +1,120 @@ +/* + * arch/xtensa/kernel/stacktrace.c + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2001 - 2013 Tensilica Inc. + */ +#include <linux/export.h> +#include <linux/sched.h> +#include <linux/stacktrace.h> + +#include <asm/stacktrace.h> +#include <asm/traps.h> + +void walk_stackframe(unsigned long *sp, + int (*fn)(struct stackframe *frame, void *data), + void *data) +{ + unsigned long a0, a1; + unsigned long sp_end; + + a1 = (unsigned long)sp; + sp_end = ALIGN(a1, THREAD_SIZE); + + spill_registers(); + + while (a1 < sp_end) { + struct stackframe frame; + + sp = (unsigned long *)a1; + + a0 = *(sp - 4); + a1 = *(sp - 3); + + if (a1 <= (unsigned long)sp) + break; + + frame.pc = MAKE_PC_FROM_RA(a0, a1); + frame.sp = a1; + + if (fn(&frame, data)) + return; + } +} + +#ifdef CONFIG_STACKTRACE + +struct stack_trace_data { + struct stack_trace *trace; + unsigned skip; +}; + +static int stack_trace_cb(struct stackframe *frame, void *data) +{ + struct stack_trace_data *trace_data = data; + struct stack_trace *trace = trace_data->trace; + + if (trace_data->skip) { + --trace_data->skip; + return 0; + } + if (!kernel_text_address(frame->pc)) + return 0; + + trace->entries[trace->nr_entries++] = frame->pc; + return trace->nr_entries >= trace->max_entries; +} + +void save_stack_trace_tsk(struct task_struct *task, struct stack_trace *trace) +{ + struct stack_trace_data trace_data = { + .trace = trace, + .skip = trace->skip, + }; + walk_stackframe(stack_pointer(task), stack_trace_cb, &trace_data); +} +EXPORT_SYMBOL_GPL(save_stack_trace_tsk); + +void save_stack_trace(struct stack_trace *trace) +{ + save_stack_trace_tsk(current, trace); +} +EXPORT_SYMBOL_GPL(save_stack_trace); + +#endif + +#ifdef CONFIG_FRAME_POINTER + +struct return_addr_data { + unsigned long addr; + unsigned skip; +}; + +static int return_address_cb(struct stackframe *frame, void *data) +{ + struct return_addr_data *r = data; + + if (r->skip) { + --r->skip; + return 0; + } + if (!kernel_text_address(frame->pc)) + return 0; + r->addr = frame->pc; + return 1; +} + +unsigned long return_address(unsigned level) +{ + struct return_addr_data r = { + .skip = level + 1, + }; + walk_stackframe(stack_pointer(NULL), return_address_cb, &r); + return r.addr; +} +EXPORT_SYMBOL(return_address); + +#endif |