#ifndef _LINUX_FTRACE_H #define _LINUX_FTRACE_H #include #include #include #include #include #include #ifdef CONFIG_FUNCTION_TRACER extern int ftrace_enabled; extern int ftrace_enable_sysctl(struct ctl_table *table, int write, struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos); typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip); struct ftrace_ops { ftrace_func_t func; struct ftrace_ops *next; }; extern int function_trace_stop; /** * ftrace_stop - stop function tracer. * * A quick way to stop the function tracer. Note this an on off switch, * it is not something that is recursive like preempt_disable. * This does not disable the calling of mcount, it only stops the * calling of functions from mcount. */ static inline void ftrace_stop(void) { function_trace_stop = 1; } /** * ftrace_start - start the function tracer. * * This function is the inverse of ftrace_stop. This does not enable * the function tracing if the function tracer is disabled. This only * sets the function tracer flag to continue calling the functions * from mcount. */ static inline void ftrace_start(void) { function_trace_stop = 0; } /* * The ftrace_ops must be a static and should also * be read_mostly. These functions do modify read_mostly variables * so use them sparely. Never free an ftrace_op or modify the * next pointer after it has been registered. Even after unregistering * it, the next pointer may still be used internally. */ int register_ftrace_function(struct ftrace_ops *ops); int unregister_ftrace_function(struct ftrace_ops *ops); void clear_ftrace_function(void); extern void ftrace_stub(unsigned long a0, unsigned long a1); #else /* !CONFIG_FUNCTION_TRACER */ # define register_ftrace_function(ops) do { } while (0) # define unregister_ftrace_function(ops) do { } while (0) # define clear_ftrace_function(ops) do { } while (0) static inline void ftrace_kill(void) { } static inline void ftrace_stop(void) { } static inline void ftrace_start(void) { } #endif /* CONFIG_FUNCTION_TRACER */ #ifdef CONFIG_DYNAMIC_FTRACE enum { FTRACE_FL_FREE = (1 << 0), FTRACE_FL_FAILED = (1 << 1), FTRACE_FL_FILTER = (1 << 2), FTRACE_FL_ENABLED = (1 << 3), FTRACE_FL_NOTRACE = (1 << 4), FTRACE_FL_CONVERTED = (1 << 5), FTRACE_FL_FROZEN = (1 << 6), }; struct dyn_ftrace { struct list_head list; unsigned long ip; /* address of mcount call-site */ unsigned long flags; }; int ftrace_force_update(void); void ftrace_set_filter(unsigned char *buf, int len, int reset); /* defined in arch */ extern int ftrace_ip_converted(unsigned long ip); extern unsigned char *ftrace_nop_replace(void); extern unsigned char *ftrace_call_replace(unsigned long ip, unsigned long addr); extern int ftrace_dyn_arch_init(void *data); extern int ftrace_update_ftrace_func(ftrace_func_t func); extern void ftrace_caller(void); extern void ftrace_call(void); extern void mcount_call(void); /* May be defined in arch */ extern int ftrace_arch_read_dyn_info(char *buf, int size); /** * ftrace_modify_code - modify code segment * @ip: the address of the code segment * @old_code: the contents of what is expected to be there * @new_code: the code to patch in * * This is a very sensitive operation and great care needs * to be taken by the arch. The operation should carefully * read the location, check to see if what is read is indeed * what we expect it to be, and then on success of the compare, * it should write to the location. * * Return must be: * 0 on success * -EFAULT on error reading the location * -EINVAL on a failed compare of the contents * -EPERM on error writing to the location * Any other value will be considered a failure. */ extern int ftrace_modify_code(unsigned long ip, unsigned char *old_code, unsigned char *new_code); extern int skip_trace(unsigned long ip); extern void ftrace_release(void *start, unsigned long size); extern void ftrace_disable_daemon(void); extern void ftrace_enable_daemon(void); #else # define skip_trace(ip) ({ 0; }) # define ftrace_force_update() ({ 0; }) # define ftrace_set_filter(buf, len, reset) do { } while (0) # define ftrace_disable_daemon() do { } while (0) # define ftrace_enable_daemon() do { } while (0) static inline void ftrace_release(void *start, unsigned long size) { } #endif /* CONFIG_DYNAMIC_FTRACE */ /* totally disable ftrace - can not re-enable after this */ void ftrace_kill(void); static inline void tracer_disable(void) { #ifdef CONFIG_FUNCTION_TRACER ftrace_enabled = 0; #endif } /* * Ftrace disable/restore without lock. Some synchronization mechanism * must be used to prevent ftrace_enabled to be changed between * disable/restore. */ static inline int __ftrace_enabled_save(void) { #ifdef CONFIG_FUNCTION_TRACER int saved_ftrace_enabled = ftrace_enabled; ftrace_enabled = 0; return saved_ftrace_enabled; #else return 0; #endif } static inline void __ftrace_enabled_restore(int enabled) { #ifdef CONFIG_FUNCTION_TRACER ftrace_enabled = enabled; #endif } #ifdef CONFIG_FRAME_POINTER /* TODO: need to fix this for ARM */ # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0)) # define CALLER_ADDR1 ((unsigned long)__builtin_return_address(1)) # define CALLER_ADDR2 ((unsigned long)__builtin_return_address(2)) # define CALLER_ADDR3 ((unsigned long)__builtin_return_address(3)) # define CALLER_ADDR4 ((unsigned long)__builtin_return_address(4)) # define CALLER_ADDR5 ((unsigned long)__builtin_return_address(5)) # define CALLER_ADDR6 ((unsigned long)__builtin_return_address(6)) #else # define CALLER_ADDR0 ((unsigned long)__builtin_return_address(0)) # define CALLER_ADDR1 0UL # define CALLER_ADDR2 0UL # define CALLER_ADDR3 0UL # define CALLER_ADDR4 0UL # define CALLER_ADDR5 0UL # define CALLER_ADDR6 0UL #endif #ifdef CONFIG_IRQSOFF_TRACER extern void time_hardirqs_on(unsigned long a0, unsigned long a1); extern void time_hardirqs_off(unsigned long a0, unsigned long a1); #else # define time_hardirqs_on(a0, a1) do { } while (0) # define time_hardirqs_off(a0, a1) do { } while (0) #endif #ifdef CONFIG_PREEMPT_TRACER extern void trace_preempt_on(unsigned long a0, unsigned long a1); extern void trace_preempt_off(unsigned long a0, unsigned long a1); #else # define trace_preempt_on(a0, a1) do { } while (0) # define trace_preempt_off(a0, a1) do { } while (0) #endif #ifdef CONFIG_TRACING extern int ftrace_dump_on_oops; extern void tracing_start(void); extern void tracing_stop(void); extern void ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3); /** * ftrace_printk - printf formatting in the ftrace buffer * @fmt: the printf format for printing * * Note: __ftrace_printk is an internal function for ftrace_printk and * the @ip is passed in via the ftrace_printk macro. * * This function allows a kernel developer to debug fast path sections * that printk is not appropriate for. By scattering in various * printk like tracing in the code, a developer can quickly see * where problems are occurring. * * This is intended as a debugging tool for the developer only. * Please refrain from leaving ftrace_printks scattered around in * your code. */ # define ftrace_printk(fmt...) __ftrace_printk(_THIS_IP_, fmt) extern int __ftrace_printk(unsigned long ip, const char *fmt, ...) __attribute__ ((format (printf, 2, 3))); extern void ftrace_dump(void); #else static inline void ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { } static inline int ftrace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 0))); static inline void tracing_start(void) { } static inline void tracing_stop(void) { } static inline int ftrace_printk(const char *fmt, ...) { return 0; } static inline void ftrace_dump(void) { } #endif #ifdef CONFIG_FTRACE_MCOUNT_RECORD extern void ftrace_init(void); extern void ftrace_init_module(unsigned long *start, unsigned long *end); #else static inline void ftrace_init(void) { } static inline void ftrace_init_module(unsigned long *start, unsigned long *end) { } #endif /* * Structure that defines a return function trace. */ struct ftrace_retfunc { unsigned long ret; /* Return address */ unsigned long func; /* Current function */ unsigned long long calltime; unsigned long long rettime; }; #ifdef CONFIG_FUNCTION_RET_TRACER /* Type of a callback handler of tracing return function */ typedef void (*trace_function_return_t)(struct ftrace_retfunc *); extern void register_ftrace_return(trace_function_return_t func); /* The current handler in use */ extern trace_function_return_t ftrace_function_return; extern void unregister_ftrace_return(void); #endif #endif /* _LINUX_FTRACE_H */