diff options
| -rw-r--r-- | include/linux/ftrace.h | 18 | ||||
| -rw-r--r-- | kernel/trace/trace_stack.c | 42 |
2 files changed, 17 insertions, 43 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 730876187344..20899919ead8 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -241,21 +241,11 @@ static inline void ftrace_free_mem(struct module *mod, void *start, void *end) { #ifdef CONFIG_STACK_TRACER -#define STACK_TRACE_ENTRIES 500 - -struct stack_trace; - -extern unsigned stack_trace_index[]; -extern struct stack_trace stack_trace_max; -extern unsigned long stack_trace_max_size; -extern arch_spinlock_t stack_trace_max_lock; - extern int stack_tracer_enabled; -void stack_trace_print(void); -int -stack_trace_sysctl(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, - loff_t *ppos); + +int stack_trace_sysctl(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, + loff_t *ppos); /* DO NOT MODIFY THIS VARIABLE DIRECTLY! */ DECLARE_PER_CPU(int, disable_stack_tracer); diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index c6e54ff25cae..4efda5f75a0f 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -18,30 +18,26 @@ #include "trace.h" -static unsigned long stack_dump_trace[STACK_TRACE_ENTRIES + 1]; -unsigned stack_trace_index[STACK_TRACE_ENTRIES]; +#define STACK_TRACE_ENTRIES 500 + +static unsigned long stack_dump_trace[STACK_TRACE_ENTRIES]; +static unsigned stack_trace_index[STACK_TRACE_ENTRIES]; -/* - * Reserve one entry for the passed in ip. This will allow - * us to remove most or all of the stack size overhead - * added by the stack tracer itself. - */ struct stack_trace stack_trace_max = { - .max_entries = STACK_TRACE_ENTRIES - 1, + .max_entries = STACK_TRACE_ENTRIES, .entries = &stack_dump_trace[0], }; -unsigned long stack_trace_max_size; -arch_spinlock_t stack_trace_max_lock = +static unsigned long stack_trace_max_size; +static arch_spinlock_t stack_trace_max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; DEFINE_PER_CPU(int, disable_stack_tracer); static DEFINE_MUTEX(stack_sysctl_mutex); int stack_tracer_enabled; -static int last_stack_tracer_enabled; -void stack_trace_print(void) +static void print_max_stack(void) { long i; int size; @@ -61,16 +57,7 @@ void stack_trace_print(void) } } -/* - * When arch-specific code overrides this function, the following - * data should be filled up, assuming stack_trace_max_lock is held to - * prevent concurrent updates. - * stack_trace_index[] - * stack_trace_max - * stack_trace_max_size - */ -void __weak -check_stack(unsigned long ip, unsigned long *stack) +static void check_stack(unsigned long ip, unsigned long *stack) { unsigned long this_size, flags; unsigned long *p, *top, *start; static int tracer_frame; @@ -179,7 +166,7 @@ check_stack(unsigned long ip, unsigned long *stack) stack_trace_max.nr_entries = x; if (task_stack_end_corrupted(current)) { - stack_trace_print(); + print_max_stack(); BUG(); } @@ -412,23 +399,21 @@ stack_trace_sysctl(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { + int was_enabled; int ret; mutex_lock(&stack_sysctl_mutex); + was_enabled = !!stack_tracer_enabled; ret = proc_dointvec(table, write, buffer, lenp, ppos); - if (ret || !write || - (last_stack_tracer_enabled == !!stack_tracer_enabled)) + if (ret || !write || (was_enabled == !!stack_tracer_enabled)) goto out; - last_stack_tracer_enabled = !!stack_tracer_enabled; - if (stack_tracer_enabled) register_ftrace_function(&trace_ops); else unregister_ftrace_function(&trace_ops); - out: mutex_unlock(&stack_sysctl_mutex); return ret; @@ -444,7 +429,6 @@ static __init int enable_stacktrace(char *str) strncpy(stack_trace_filter_buf, str + len, COMMAND_LINE_SIZE); stack_tracer_enabled = 1; - last_stack_tracer_enabled = 1; return 1; } __setup("stacktrace", enable_stacktrace); |