/* * Ftrace header. For implementation details beyond the random comments * scattered below, see: Documentation/trace/ftrace-design.txt */ #ifndef _LINUX_FTRACE_H #define _LINUX_FTRACE_H #include #include #include #include #include #include #include #include #include #include /* * If the arch supports passing the variable contents of * function_trace_op as the third parameter back from the * mcount call, then the arch should define this as 1. */ #ifndef ARCH_SUPPORTS_FTRACE_OPS #define ARCH_SUPPORTS_FTRACE_OPS 0 #endif /* * If the arch's mcount caller does not support all of ftrace's * features, then it must call an indirect function that * does. Or at least does enough to prevent any unwelcomed side effects. */ #if !defined(CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST) || \ !ARCH_SUPPORTS_FTRACE_OPS # define FTRACE_FORCE_LIST_FUNC 1 #else # define FTRACE_FORCE_LIST_FUNC 0 #endif struct module; struct ftrace_hash; #ifdef CONFIG_FUNCTION_TRACER extern int ftrace_enabled; extern int ftrace_enable_sysctl(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos); struct ftrace_ops; typedef void (*ftrace_func_t)(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op); /* * FTRACE_OPS_FL_* bits denote the state of ftrace_ops struct and are * set in the flags member. * * ENABLED - set/unset when ftrace_ops is registered/unregistered * GLOBAL - set manualy by ftrace_ops user to denote the ftrace_ops * is part of the global tracers sharing the same filter * via set_ftrace_* debugfs files. * DYNAMIC - set when ftrace_ops is registered to denote dynamically * allocated ftrace_ops which need special care * CONTROL - set manualy by ftrace_ops user to denote the ftrace_ops * could be controled by following calls: * ftrace_function_local_enable * ftrace_function_local_disable */ enum { FTRACE_OPS_FL_ENABLED = 1 << 0, FTRACE_OPS_FL_GLOBAL = 1 << 1, FTRACE_OPS_FL_DYNAMIC = 1 << 2, FTRACE_OPS_FL_CONTROL = 1 << 3, }; struct ftrace_ops { ftrace_func_t func; struct ftrace_ops *next; unsigned long flags; int __percpu *disabled; #ifdef CONFIG_DYNAMIC_FTRACE struct ftrace_hash *notrace_hash; struct ftrace_hash *filter_hash; #endif }; extern int function_trace_stop; /* * Type of the current tracing. */ enum ftrace_tracing_type_t { FTRACE_TYPE_ENTER = 0, /* Hook the call of the function */ FTRACE_TYPE_RETURN, /* Hook the return of the function */ }; /* Current tracing type, default is FTRACE_TYPE_ENTER */ extern enum ftrace_tracing_type_t ftrace_tracing_type; /** * 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); /** * ftrace_function_local_enable - enable controlled ftrace_ops on current cpu * * This function enables tracing on current cpu by decreasing * the per cpu control variable. * It must be called with preemption disabled and only on ftrace_ops * registered with FTRACE_OPS_FL_CONTROL. If called without preemption * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled. */ static inline void ftrace_function_local_enable(struct ftrace_ops *ops) { if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL))) return; (*this_cpu_ptr(ops->disabled))--; } /** * ftrace_function_local_disable - enable controlled ftrace_ops on current cpu * * This function enables tracing on current cpu by decreasing * the per cpu control variable. * It must be called with preemption disabled and only on ftrace_ops * registered with FTRACE_OPS_FL_CONTROL. If called without preemption * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled. */ static inline void ftrace_function_local_disable(struct ftrace_ops *ops) { if (WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL))) return; (*this_cpu_ptr(ops->disabled))++; } /** * ftrace_function_local_disabled - returns ftrace_ops disabled value * on current cpu * * This function returns value of ftrace_ops::disabled on current cpu. * It must be called with preemption disabled and only on ftrace_ops * registered with FTRACE_OPS_FL_CONTROL. If called without preemption * disabled, this_cpu_ptr will complain when CONFIG_DEBUG_PREEMPT is enabled. */ static inline int ftrace_function_local_disabled(struct ftrace_ops *ops) { WARN_ON_ONCE(!(ops->flags & FTRACE_OPS_FL_CONTROL)); return *this_cpu_ptr(ops->disabled); } extern void ftrace_stub(unsigned long a0, unsigned long a1, struct ftrace_ops *op); #else /* !CONFIG_FUNCTION_TRACER */ /* * (un)register_ftrace_function must be a macro since the ops parameter * must not be evaluated. */ #define register_ftrace_function(ops) ({ 0; }) #define unregister_ftrace_function(ops) ({ 0; }) static inline void clear_ftrace_function(void) { } static inline void ftrace_kill(void) { } static inline void ftrace_stop(void) { } static inline void ftrace_start(void) { } #endif /* CONFIG_FUNCTION_TRACER */ #ifdef CONFIG_STACK_TRACER extern int stack_tracer_enabled; int stack_trace_sysctl(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos); #endif struct ftrace_func_command { struct list_head list; char *name; int (*func)(struct ftrace_hash *hash, char *func, char *cmd, char *params, int enable); }; #ifdef CONFIG_DYNAMIC_FTRACE int ftrace_arch_code_modify_prepare(void); int ftrace_arch_code_modify_post_process(void); void ftrace_bug(int err, unsigned long ip); struct seq_file; struct ftrace_probe_ops { void (*func)(unsigned long ip, unsigned long parent_ip, void **data); int (*callback)(unsigned long ip, void **data); void (*free)(void **data); int (*print)(struct seq_file *m, unsigned long ip, struct ftrace_probe_ops *ops, void *data); }; extern int register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, void *data); extern void unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, void *data); extern void unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops); extern void unregister_ftrace_function_probe_all(char *glob); extern int ftrace_text_reserved(void *start, void *end); enum { FTRACE_FL_ENABLED = (1 << 30), }; #define FTRACE_FL_MASK (0x3UL << 30) #define FTRACE_REF_MAX ((1 << 30) - 1) struct dyn_ftrace { union { unsigned long ip; /* address of mcount call-site */ struct dyn_ftrace *freelist; }; unsigned long flags; struct dyn_arch_ftrace arch; }; int ftrace_force_update(void); int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf, int len, int reset); int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf, int len, int reset); void ftrace_set_global_filter(unsigned char *buf, int len, int reset); void ftrace_set_global_notrace(unsigned char *buf, int len, int reset); void ftrace_free_filter(struct ftrace_ops *ops); int register_ftrace_command(struct ftrace_func_command *cmd); int unregister_ftrace_command(struct ftrace_func_command *cmd); enum { FTRACE_UPDATE_CALLS = (1 << 0), FTRACE_DISABLE_CALLS = (1 << 1), FTRACE_UPDATE_TRACE_FUNC = (1 << 2), FTRACE_START_FUNC_RET = (1 << 3), FTRACE_STOP_FUNC_RET = (1 << 4), }; enum { FTRACE_UPDATE_IGNORE, FTRACE_UPDATE_MAKE_CALL, FTRACE_UPDATE_MAKE_NOP, }; enum { FTRACE_ITER_FILTER = (1 << 0), FTRACE_ITER_NOTRACE = (1 << 1), FTRACE_ITER_PRINTALL = (1 << 2), FTRACE_ITER_DO_HASH = (1 << 3), FTRACE_ITER_HASH = (1 << 4), FTRACE_ITER_ENABLED = (1 << 5), }; void arch_ftrace_update_code(int command); struct ftrace_rec_iter; struct ftrace_rec_iter *ftrace_rec_iter_start(void); struct ftrace_rec_iter *ftrace_rec_iter_next(struct ftrace_rec_iter *iter); struct dyn_ftrace *ftrace_rec_iter_record(struct ftrace_rec_iter *iter); #define for_ftrace_rec_iter(iter) \ for (iter = ftrace_rec_iter_start(); \ iter; \ iter = ftrace_rec_iter_next(iter)) int ftrace_update_record(struct dyn_ftrace *rec, int enable); int ftrace_test_record(struct dyn_ftrace *rec, int enable); void ftrace_run_stop_machine(int command); unsigned long ftrace_location(unsigned long ip); extern ftrace_func_t ftrace_trace_function; int ftrace_regex_open(struct ftrace_ops *ops, int flag, struct inode *inode, struct file *file); ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos); ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos); loff_t ftrace_regex_lseek(struct file *file, loff_t offset, int origin); int ftrace_regex_release(struct inode *inode, struct file *file); void __init ftrace_set_early_filter(struct ftrace_ops *ops, char *buf, int enable); /* defined in arch */ extern int ftrace_ip_converted(unsigned long ip); extern int ftrace_dyn_arch_init(void *data); extern void ftrace_replace_code(int enable); 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); void ftrace_modify_all_code(int command); #ifndef FTRACE_ADDR #define FTRACE_ADDR ((unsigned long)ftrace_caller) #endif #ifdef CONFIG_FUNCTION_GRAPH_TRACER extern void ftrace_graph_caller(void); extern int ftrace_enable_ftrace_graph_caller(void); extern int ftrace_disable_ftrace_graph_caller(void); #else static inline int ftrace_enable_ftrace_graph_caller(void) { return 0; } static inline int ftrace_disable_ftrace_graph_caller(void) { return 0; } #endif /** * ftrace_make_nop - convert code into nop * @mod: module structure if called by module load initialization * @rec: the mcount call site record * @addr: the address that the call site should be calling * * 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. * * The code segment at @rec->ip should be a caller to @addr * * 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_make_nop(struct module *mod, struct dyn_ftrace *rec, unsigned long addr); /** * ftrace_make_call - convert a nop call site into a call to addr * @rec: the mcount call site record * @addr: the address that the call site should call * * 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. * * The code segment at @rec->ip should be a nop * * 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_make_call(struct dyn_ftrace *rec, unsigned long addr); /* May be defined in arch */ extern int ftrace_arch_read_dyn_info(char *buf, int size); extern int skip_trace(unsigned long ip); extern void ftrace_disable_daemon(void); extern void ftrace_enable_daemon(void); #else static inline int skip_trace(unsigned long ip) { return 0; } static inline int ftrace_force_update(void) { return 0; } static inline void ftrace_disable_daemon(void) { } static inline void ftrace_enable_daemon(void) { } static inline void ftrace_release_mod(struct module *mod) {} static inline int register_ftrace_command(struct ftrace_func_command *cmd) { return -EINVAL; } static inline int unregister_ftrace_command(char *cmd_name) { return -EINVAL; } static inline int ftrace_text_reserved(void *start, void *end) { return 0; } /* * Again users of functions that have ftrace_ops may not * have them defined when ftrace is not enabled, but these * functions may still be called. Use a macro instead of inline. */ #define ftrace_regex_open(ops, flag, inod, file) ({ -ENODEV; }) #define ftrace_set_early_filter(ops, buf, enable) do { } while (0) #define ftrace_set_filter(ops, buf, len, reset) ({ -ENODEV; }) #define ftrace_set_notrace(ops, buf, len, reset) ({ -ENODEV; }) #define ftrace_free_filter(ops) do { } while (0) static inline ssize_t ftrace_filter_write(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos) { return -ENODEV; } static inline ssize_t ftrace_notrace_write(struct file *file, const char __user *ubuf, size_t cnt, loff_t *ppos) { return -ENODEV; } static inline loff_t ftrace_regex_lseek(struct file *file, loff_t offset, int origin) { return -ENODEV; } static inline int ftrace_regex_release(struct inode *inode, struct file *file) { return -ENODEV; } #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 } #ifndef HAVE_ARCH_CALLER_ADDR # ifdef CONFIG_FRAME_POINTER # 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 #endif /* ifndef HAVE_ARCH_CALLER_ADDR */ #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 static inline void time_hardirqs_on(unsigned long a0, unsigned long a1) { } static inline void time_hardirqs_off(unsigned long a0, unsigned long a1) { } #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 /* * Use defines instead of static inlines because some arches will make code out * of the CALLER_ADDR, when we really want these to be a real nop. */ # define trace_preempt_on(a0, a1) do { } while (0) # define trace_preempt_off(a0, a1) do { } while (0) #endif #ifdef CONFIG_FTRACE_MCOUNT_RECORD extern void ftrace_init(void); #else static inline void ftrace_init(void) { } #endif /* * Structure that defines an entry function trace. */ struct ftrace_graph_ent { unsigned long func; /* Current function */ int depth; }; /* * Structure that defines a return function trace. */ struct ftrace_graph_ret { unsigned long func; /* Current function */ unsigned long long calltime; unsigned long long rettime; /* Number of functions that overran the depth limit for current task */ unsigned long overrun; int depth; }; /* Type of the callback handlers for tracing function graph*/ typedef void (*trace_func_graph_ret_t)(struct ftrace_graph_ret *); /* return */ typedef int (*trace_func_graph_ent_t)(struct ftrace_graph_ent *); /* entry */ #ifdef CONFIG_FUNCTION_GRAPH_TRACER /* for init task */ #define INIT_FTRACE_GRAPH .ret_stack = NULL, /* * Stack of return addresses for functions * of a thread. * Used in struct thread_info */ struct ftrace_ret_stack { unsigned long ret; unsigned long func; unsigned long long calltime; unsigned long long subtime; unsigned long fp; }; /* * Primary handler of a function return. * It relays on ftrace_return_to_handler. * Defined in entry_32/64.S */ extern void return_to_handler(void); extern int ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth, unsigned long frame_pointer); /* * Sometimes we don't want to trace a function with the function * graph tracer but we want them to keep traced by the usual function * tracer if the function graph tracer is not configured. */ #define __notrace_funcgraph notrace /* * We want to which function is an entrypoint of a hardirq. * That will help us to put a signal on output. */ #define __irq_entry __attribute__((__section__(".irqentry.text"))) /* Limits of hardirq entrypoints */ extern char __irqentry_text_start[]; extern char __irqentry_text_end[]; #define FTRACE_RETFUNC_DEPTH 50 #define FTRACE_RETSTACK_ALLOC_SIZE 32 extern int register_ftrace_graph(trace_func_graph_ret_t retfunc, trace_func_graph_ent_t entryfunc); extern void ftrace_graph_stop(void); /* The current handlers in use */ extern trace_func_graph_ret_t ftrace_graph_return; extern trace_func_graph_ent_t ftrace_graph_entry; extern void unregister_ftrace_graph(void); extern void ftrace_graph_init_task(struct task_struct *t); extern void ftrace_graph_exit_task(struct task_struct *t); extern void ftrace_graph_init_idle_task(struct task_struct *t, int cpu); static inline int task_curr_ret_stack(struct task_struct *t) { return t->curr_ret_stack; } static inline void pause_graph_tracing(void) { atomic_inc(¤t->tracing_graph_pause); } static inline void unpause_graph_tracing(void) { atomic_dec(¤t->tracing_graph_pause); } #else /* !CONFIG_FUNCTION_GRAPH_TRACER */ #define __notrace_funcgraph #define __irq_entry #define INIT_FTRACE_GRAPH static inline void ftrace_graph_init_task(struct task_struct *t) { } static inline void ftrace_graph_exit_task(struct task_struct *t) { } static inline void ftrace_graph_init_idle_task(struct task_struct *t, int cpu) { } static inline int register_ftrace_graph(trace_func_graph_ret_t retfunc, trace_func_graph_ent_t entryfunc) { return -1; } static inline void unregister_ftrace_graph(void) { } static inline int task_curr_ret_stack(struct task_struct *tsk) { return -1; } static inline void pause_graph_tracing(void) { } static inline void unpause_graph_tracing(void) { } #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ #ifdef CONFIG_TRACING /* flags for current->trace */ enum { TSK_TRACE_FL_TRACE_BIT = 0, TSK_TRACE_FL_GRAPH_BIT = 1, }; enum { TSK_TRACE_FL_TRACE = 1 << TSK_TRACE_FL_TRACE_BIT, TSK_TRACE_FL_GRAPH = 1 << TSK_TRACE_FL_GRAPH_BIT, }; static inline void set_tsk_trace_trace(struct task_struct *tsk) { set_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace); } static inline void clear_tsk_trace_trace(struct task_struct *tsk) { clear_bit(TSK_TRACE_FL_TRACE_BIT, &tsk->trace); } static inline int test_tsk_trace_trace(struct task_struct *tsk) { return tsk->trace & TSK_TRACE_FL_TRACE; } static inline void set_tsk_trace_graph(struct task_struct *tsk) { set_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace); } static inline void clear_tsk_trace_graph(struct task_struct *tsk) { clear_bit(TSK_TRACE_FL_GRAPH_BIT, &tsk->trace); } static inline int test_tsk_trace_graph(struct task_struct *tsk) { return tsk->trace & TSK_TRACE_FL_GRAPH; } enum ftrace_dump_mode; extern enum ftrace_dump_mode ftrace_dump_on_oops; #ifdef CONFIG_PREEMPT #define INIT_TRACE_RECURSION .trace_recursion = 0, #endif #endif /* CONFIG_TRACING */ #ifndef INIT_TRACE_RECURSION #define INIT_TRACE_RECURSION #endif #ifdef CONFIG_FTRACE_SYSCALLS unsigned long arch_syscall_addr(int nr); #endif /* CONFIG_FTRACE_SYSCALLS */ #endif /* _LINUX_FTRACE_H */