diff options
Diffstat (limited to 'include/linux/ftrace.h')
| -rw-r--r-- | include/linux/ftrace.h | 905 |
1 files changed, 905 insertions, 0 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h new file mode 100644 index 000000000..1da602982 --- /dev/null +++ b/include/linux/ftrace.h @@ -0,0 +1,905 @@ +/* + * 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 <linux/trace_clock.h> +#include <linux/kallsyms.h> +#include <linux/linkage.h> +#include <linux/bitops.h> +#include <linux/ptrace.h> +#include <linux/ktime.h> +#include <linux/sched.h> +#include <linux/types.h> +#include <linux/init.h> +#include <linux/fs.h> + +#include <asm/ftrace.h> + +/* + * 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 !ARCH_SUPPORTS_FTRACE_OPS +# define FTRACE_FORCE_LIST_FUNC 1 +#else +# define FTRACE_FORCE_LIST_FUNC 0 +#endif + +/* Main tracing buffer and events set up */ +#ifdef CONFIG_TRACING +void trace_init(void); +#else +static inline void trace_init(void) { } +#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, struct pt_regs *regs); + +ftrace_func_t ftrace_ops_get_func(struct ftrace_ops *ops); + +/* + * FTRACE_OPS_FL_* bits denote the state of ftrace_ops struct and are + * set in the flags member. + * CONTROL, SAVE_REGS, SAVE_REGS_IF_SUPPORTED, RECURSION_SAFE, STUB and + * IPMODIFY are a kind of attribute flags which can be set only before + * registering the ftrace_ops, and can not be modified while registered. + * Changing those attribute flags after regsitering ftrace_ops will + * cause unexpected results. + * + * ENABLED - set/unset when ftrace_ops is registered/unregistered + * 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 + * SAVE_REGS - The ftrace_ops wants regs saved at each function called + * and passed to the callback. If this flag is set, but the + * architecture does not support passing regs + * (CONFIG_DYNAMIC_FTRACE_WITH_REGS is not defined), then the + * ftrace_ops will fail to register, unless the next flag + * is set. + * SAVE_REGS_IF_SUPPORTED - This is the same as SAVE_REGS, but if the + * handler can handle an arch that does not save regs + * (the handler tests if regs == NULL), then it can set + * this flag instead. It will not fail registering the ftrace_ops + * but, the regs field will be NULL if the arch does not support + * passing regs to the handler. + * Note, if this flag is set, the SAVE_REGS flag will automatically + * get set upon registering the ftrace_ops, if the arch supports it. + * RECURSION_SAFE - The ftrace_ops can set this to tell the ftrace infrastructure + * that the call back has its own recursion protection. If it does + * not set this, then the ftrace infrastructure will add recursion + * protection for the caller. + * STUB - The ftrace_ops is just a place holder. + * INITIALIZED - The ftrace_ops has already been initialized (first use time + * register_ftrace_function() is called, it will initialized the ops) + * DELETED - The ops are being deleted, do not let them be registered again. + * ADDING - The ops is in the process of being added. + * REMOVING - The ops is in the process of being removed. + * MODIFYING - The ops is in the process of changing its filter functions. + * ALLOC_TRAMP - A dynamic trampoline was allocated by the core code. + * The arch specific code sets this flag when it allocated a + * trampoline. This lets the arch know that it can update the + * trampoline in case the callback function changes. + * The ftrace_ops trampoline can be set by the ftrace users, and + * in such cases the arch must not modify it. Only the arch ftrace + * core code should set this flag. + * IPMODIFY - The ops can modify the IP register. This can only be set with + * SAVE_REGS. If another ops with this flag set is already registered + * for any of the functions that this ops will be registered for, then + * this ops will fail to register or set_filter_ip. + */ +enum { + FTRACE_OPS_FL_ENABLED = 1 << 0, + FTRACE_OPS_FL_DYNAMIC = 1 << 1, + FTRACE_OPS_FL_CONTROL = 1 << 2, + FTRACE_OPS_FL_SAVE_REGS = 1 << 3, + FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED = 1 << 4, + FTRACE_OPS_FL_RECURSION_SAFE = 1 << 5, + FTRACE_OPS_FL_STUB = 1 << 6, + FTRACE_OPS_FL_INITIALIZED = 1 << 7, + FTRACE_OPS_FL_DELETED = 1 << 8, + FTRACE_OPS_FL_ADDING = 1 << 9, + FTRACE_OPS_FL_REMOVING = 1 << 10, + FTRACE_OPS_FL_MODIFYING = 1 << 11, + FTRACE_OPS_FL_ALLOC_TRAMP = 1 << 12, + FTRACE_OPS_FL_IPMODIFY = 1 << 13, +}; + +#ifdef CONFIG_DYNAMIC_FTRACE +/* The hash used to know what functions callbacks trace */ +struct ftrace_ops_hash { + struct ftrace_hash *notrace_hash; + struct ftrace_hash *filter_hash; + struct mutex regex_lock; +}; +#endif + +/* + * Note, ftrace_ops can be referenced outside of RCU protection. + * (Although, for perf, the control ops prevent that). If ftrace_ops is + * allocated and not part of kernel core data, the unregistering of it will + * perform a scheduling on all CPUs to make sure that there are no more users. + * Depending on the load of the system that may take a bit of time. + * + * Any private data added must also take care not to be freed and if private + * data is added to a ftrace_ops that is in core code, the user of the + * ftrace_ops must perform a schedule_on_each_cpu() before freeing it. + */ +struct ftrace_ops { + ftrace_func_t func; + struct ftrace_ops *next; + unsigned long flags; + void *private; + int __percpu *disabled; +#ifdef CONFIG_DYNAMIC_FTRACE + int nr_trampolines; + struct ftrace_ops_hash local_hash; + struct ftrace_ops_hash *func_hash; + struct ftrace_ops_hash old_hash; + unsigned long trampoline; + unsigned long trampoline_size; +#endif +}; + +/* + * 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; + +/* + * 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, struct pt_regs *regs); + +#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 int ftrace_nr_registered_ops(void) +{ + return 0; +} +static inline void clear_ftrace_function(void) { } +static inline void ftrace_kill(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); + +struct dyn_ftrace; + +void ftrace_bug(int err, struct dyn_ftrace *rec); + +struct seq_file; + +struct ftrace_probe_ops { + void (*func)(unsigned long ip, + unsigned long parent_ip, + void **data); + int (*init)(struct ftrace_probe_ops *ops, + unsigned long ip, void **data); + void (*free)(struct ftrace_probe_ops *ops, + unsigned long ip, 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(const void *start, const void *end); + +extern int ftrace_nr_registered_ops(void); + +bool is_ftrace_trampoline(unsigned long addr); + +/* + * The dyn_ftrace record's flags field is split into two parts. + * the first part which is '0-FTRACE_REF_MAX' is a counter of + * the number of callbacks that have registered the function that + * the dyn_ftrace descriptor represents. + * + * The second part is a mask: + * ENABLED - the function is being traced + * REGS - the record wants the function to save regs + * REGS_EN - the function is set up to save regs. + * IPMODIFY - the record allows for the IP address to be changed. + * + * When a new ftrace_ops is registered and wants a function to save + * pt_regs, the rec->flag REGS is set. When the function has been + * set up to save regs, the REG_EN flag is set. Once a function + * starts saving regs it will do so until all ftrace_ops are removed + * from tracing that function. + */ +enum { + FTRACE_FL_ENABLED = (1UL << 31), + FTRACE_FL_REGS = (1UL << 30), + FTRACE_FL_REGS_EN = (1UL << 29), + FTRACE_FL_TRAMP = (1UL << 28), + FTRACE_FL_TRAMP_EN = (1UL << 27), + FTRACE_FL_IPMODIFY = (1UL << 26), +}; + +#define FTRACE_REF_MAX_SHIFT 26 +#define FTRACE_FL_BITS 6 +#define FTRACE_FL_MASKED_BITS ((1UL << FTRACE_FL_BITS) - 1) +#define FTRACE_FL_MASK (FTRACE_FL_MASKED_BITS << FTRACE_REF_MAX_SHIFT) +#define FTRACE_REF_MAX ((1UL << FTRACE_REF_MAX_SHIFT) - 1) + +#define ftrace_rec_count(rec) ((rec)->flags & ~FTRACE_FL_MASK) + +struct dyn_ftrace { + unsigned long ip; /* address of mcount call-site */ + unsigned long flags; + struct dyn_arch_ftrace arch; +}; + +int ftrace_force_update(void); +int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip, + int remove, int reset); +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), +}; + +/* + * The FTRACE_UPDATE_* enum is used to pass information back + * from the ftrace_update_record() and ftrace_test_record() + * functions. These are called by the code update routines + * to find out what is to be done for a given function. + * + * IGNORE - The function is already what we want it to be + * MAKE_CALL - Start tracing the function + * MODIFY_CALL - Stop saving regs for the function + * MAKE_NOP - Stop tracing the function + */ +enum { + FTRACE_UPDATE_IGNORE, + FTRACE_UPDATE_MAKE_CALL, + FTRACE_UPDATE_MODIFY_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); +unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec); +unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec); + +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); +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); +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_regs_caller(void); +extern void ftrace_call(void); +extern void ftrace_regs_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 + +#ifndef FTRACE_GRAPH_ADDR +#define FTRACE_GRAPH_ADDR ((unsigned long)ftrace_graph_caller) +#endif + +#ifndef FTRACE_REGS_ADDR +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS +# define FTRACE_REGS_ADDR ((unsigned long)ftrace_regs_caller) +#else +# define FTRACE_REGS_ADDR FTRACE_ADDR +#endif +#endif + +/* + * If an arch would like functions that are only traced + * by the function graph tracer to jump directly to its own + * trampoline, then they can define FTRACE_GRAPH_TRAMP_ADDR + * to be that address to jump to. + */ +#ifndef FTRACE_GRAPH_TRAMP_ADDR +#define FTRACE_GRAPH_TRAMP_ADDR ((unsigned long) 0) +#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); + +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS +/** + * ftrace_modify_call - convert from one addr to another (no nop) + * @rec: the mcount call site record + * @old_addr: the address expected to be currently called to + * @addr: the address to change to + * + * 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 @old_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_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, + unsigned long addr); +#else +/* Should never be called */ +static inline int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr, + unsigned long addr) +{ + return -EINVAL; +} +#endif + +/* 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_module_init(struct module *mod); + +extern void ftrace_disable_daemon(void); +extern void ftrace_enable_daemon(void); +#else /* CONFIG_DYNAMIC_FTRACE */ +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 void ftrace_module_init(struct module *mod) {} +static inline __init int register_ftrace_command(struct ftrace_func_command *cmd) +{ + return -EINVAL; +} +static inline __init int unregister_ftrace_command(char *cmd_name) +{ + return -EINVAL; +} +static inline int ftrace_text_reserved(const void *start, const void *end) +{ + return 0; +} +static inline unsigned long ftrace_location(unsigned long ip) +{ + 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_ip(ops, ip, remove, reset) ({ -ENODEV; }) +#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 int +ftrace_regex_release(struct inode *inode, struct file *file) { return -ENODEV; } + +static inline bool is_ftrace_trampoline(unsigned long addr) +{ + return false; +} +#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 +} + +/* All archs should have this, but we define it for consistency */ +#ifndef ftrace_return_address0 +# define ftrace_return_address0 __builtin_return_address(0) +#endif + +/* Archs may use other ways for ADDR1 and beyond */ +#ifndef ftrace_return_address +# ifdef CONFIG_FRAME_POINTER +# define ftrace_return_address(n) __builtin_return_address(n) +# else +# define ftrace_return_address(n) 0UL +# endif +#endif + +#define CALLER_ADDR0 ((unsigned long)ftrace_return_address0) +#define CALLER_ADDR1 ((unsigned long)ftrace_return_address(1)) +#define CALLER_ADDR2 ((unsigned long)ftrace_return_address(2)) +#define CALLER_ADDR3 ((unsigned long)ftrace_return_address(3)) +#define CALLER_ADDR4 ((unsigned long)ftrace_return_address(4)) +#define CALLER_ADDR5 ((unsigned long)ftrace_return_address(5)) +#define CALLER_ADDR6 ((unsigned long)ftrace_return_address(6)) + +#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_NOTRACE_DEPTH 65536 +#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 bool ftrace_graph_is_dead(void); +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; +extern int tracepoint_printk; + +extern void disable_trace_on_warning(void); +extern int __disable_trace_on_warning; + +#ifdef CONFIG_PREEMPT +#define INIT_TRACE_RECURSION .trace_recursion = 0, +#endif + +#else /* CONFIG_TRACING */ +static inline void disable_trace_on_warning(void) { } +#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 */ |