diff options
Diffstat (limited to 'arch/openrisc/kernel/stacktrace.c')
-rw-r--r-- | arch/openrisc/kernel/stacktrace.c | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/arch/openrisc/kernel/stacktrace.c b/arch/openrisc/kernel/stacktrace.c new file mode 100644 index 0000000000..54d38809e2 --- /dev/null +++ b/arch/openrisc/kernel/stacktrace.c @@ -0,0 +1,100 @@ +/* + * Stack trace utility for OpenRISC + * + * Copyright (C) 2017 Stafford Horne <shorne@gmail.com> + * + * This file is licensed under the terms of the GNU General Public License + * version 2. This program is licensed "as is" without any warranty of any + * kind, whether express or implied. + * + * Losely based on work from sh and powerpc. + */ + +#include <linux/export.h> +#include <linux/sched.h> +#include <linux/sched/debug.h> +#include <linux/sched/task_stack.h> +#include <linux/stacktrace.h> + +#include <asm/processor.h> +#include <asm/unwinder.h> + +/* + * Save stack-backtrace addresses into a stack_trace buffer. + */ +static void +save_stack_address(void *data, unsigned long addr, int reliable) +{ + struct stack_trace *trace = data; + + if (!reliable) + return; + + if (trace->skip > 0) { + trace->skip--; + return; + } + + if (trace->nr_entries < trace->max_entries) + trace->entries[trace->nr_entries++] = addr; +} + +void save_stack_trace(struct stack_trace *trace) +{ + unwind_stack(trace, (unsigned long *) &trace, save_stack_address); +} +EXPORT_SYMBOL_GPL(save_stack_trace); + +static void +save_stack_address_nosched(void *data, unsigned long addr, int reliable) +{ + struct stack_trace *trace = (struct stack_trace *)data; + + if (!reliable) + return; + + if (in_sched_functions(addr)) + return; + + if (trace->skip > 0) { + trace->skip--; + return; + } + + if (trace->nr_entries < trace->max_entries) + trace->entries[trace->nr_entries++] = addr; +} + +void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) +{ + unsigned long *sp = NULL; + + if (!try_get_task_stack(tsk)) + return; + + if (tsk == current) + sp = (unsigned long *) &sp; + else { + unsigned long ksp; + + /* Locate stack from kernel context */ + ksp = task_thread_info(tsk)->ksp; + ksp += STACK_FRAME_OVERHEAD; /* redzone */ + ksp += sizeof(struct pt_regs); + + sp = (unsigned long *) ksp; + } + + unwind_stack(trace, sp, save_stack_address_nosched); + + put_task_stack(tsk); +} +EXPORT_SYMBOL_GPL(save_stack_trace_tsk); + +void +save_stack_trace_regs(struct pt_regs *regs, struct stack_trace *trace) +{ + unwind_stack(trace, (unsigned long *) regs->sp, + save_stack_address_nosched); +} +EXPORT_SYMBOL_GPL(save_stack_trace_regs); |