alistair23-linux/include/linux/stacktrace.h
Mark Brown 264c03a245 stacktrace: Remove reliable argument from arch_stack_walk() callback
Currently the callback passed to arch_stack_walk() has an argument called
reliable passed to it to indicate if the stack entry is reliable, a comment
says that this is used by some printk() consumers. However in the current
kernel none of the arch_stack_walk() implementations ever set this flag to
true and the only callback implementation we have is in the generic
stacktrace code which ignores the flag. It therefore appears that this
flag is redundant so we can simplify and clarify things by removing it.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lore.kernel.org/r/20200914153409.25097-2-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-18 14:24:16 +01:00

91 lines
3.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_STACKTRACE_H
#define __LINUX_STACKTRACE_H
#include <linux/types.h>
#include <asm/errno.h>
struct task_struct;
struct pt_regs;
#ifdef CONFIG_STACKTRACE
void stack_trace_print(const unsigned long *trace, unsigned int nr_entries,
int spaces);
int stack_trace_snprint(char *buf, size_t size, const unsigned long *entries,
unsigned int nr_entries, int spaces);
unsigned int stack_trace_save(unsigned long *store, unsigned int size,
unsigned int skipnr);
unsigned int stack_trace_save_tsk(struct task_struct *task,
unsigned long *store, unsigned int size,
unsigned int skipnr);
unsigned int stack_trace_save_regs(struct pt_regs *regs, unsigned long *store,
unsigned int size, unsigned int skipnr);
unsigned int stack_trace_save_user(unsigned long *store, unsigned int size);
/* Internal interfaces. Do not use in generic code */
#ifdef CONFIG_ARCH_STACKWALK
/**
* stack_trace_consume_fn - Callback for arch_stack_walk()
* @cookie: Caller supplied pointer handed back by arch_stack_walk()
* @addr: The stack entry address to consume
*
* Return: True, if the entry was consumed or skipped
* False, if there is no space left to store
*/
typedef bool (*stack_trace_consume_fn)(void *cookie, unsigned long addr);
/**
* arch_stack_walk - Architecture specific function to walk the stack
* @consume_entry: Callback which is invoked by the architecture code for
* each entry.
* @cookie: Caller supplied pointer which is handed back to
* @consume_entry
* @task: Pointer to a task struct, can be NULL
* @regs: Pointer to registers, can be NULL
*
* ============ ======= ============================================
* task regs
* ============ ======= ============================================
* task NULL Stack trace from task (can be current)
* current regs Stack trace starting on regs->stackpointer
* ============ ======= ============================================
*/
void arch_stack_walk(stack_trace_consume_fn consume_entry, void *cookie,
struct task_struct *task, struct pt_regs *regs);
int arch_stack_walk_reliable(stack_trace_consume_fn consume_entry, void *cookie,
struct task_struct *task);
void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie,
const struct pt_regs *regs);
#else /* CONFIG_ARCH_STACKWALK */
struct stack_trace {
unsigned int nr_entries, max_entries;
unsigned long *entries;
unsigned int skip; /* input argument: How many entries to skip */
};
extern void save_stack_trace(struct stack_trace *trace);
extern void save_stack_trace_regs(struct pt_regs *regs,
struct stack_trace *trace);
extern void save_stack_trace_tsk(struct task_struct *tsk,
struct stack_trace *trace);
extern int save_stack_trace_tsk_reliable(struct task_struct *tsk,
struct stack_trace *trace);
extern void save_stack_trace_user(struct stack_trace *trace);
#endif /* !CONFIG_ARCH_STACKWALK */
#endif /* CONFIG_STACKTRACE */
#if defined(CONFIG_STACKTRACE) && defined(CONFIG_HAVE_RELIABLE_STACKTRACE)
int stack_trace_save_tsk_reliable(struct task_struct *tsk, unsigned long *store,
unsigned int size);
#else
static inline int stack_trace_save_tsk_reliable(struct task_struct *tsk,
unsigned long *store,
unsigned int size)
{
return -ENOSYS;
}
#endif
#endif /* __LINUX_STACKTRACE_H */