diff options
Diffstat (limited to 'include/linux/trace_events.h')
| -rw-r--r-- | include/linux/trace_events.h | 634 |
1 files changed, 634 insertions, 0 deletions
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h new file mode 100644 index 000000000..0643c083e --- /dev/null +++ b/include/linux/trace_events.h @@ -0,0 +1,634 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _LINUX_TRACE_EVENT_H +#define _LINUX_TRACE_EVENT_H + +#include <linux/ring_buffer.h> +#include <linux/trace_seq.h> +#include <linux/percpu.h> +#include <linux/hardirq.h> +#include <linux/perf_event.h> +#include <linux/tracepoint.h> + +struct trace_array; +struct trace_buffer; +struct tracer; +struct dentry; +struct bpf_prog; + +const char *trace_print_flags_seq(struct trace_seq *p, const char *delim, + unsigned long flags, + const struct trace_print_flags *flag_array); + +const char *trace_print_symbols_seq(struct trace_seq *p, unsigned long val, + const struct trace_print_flags *symbol_array); + +#if BITS_PER_LONG == 32 +const char *trace_print_flags_seq_u64(struct trace_seq *p, const char *delim, + unsigned long long flags, + const struct trace_print_flags_u64 *flag_array); + +const char *trace_print_symbols_seq_u64(struct trace_seq *p, + unsigned long long val, + const struct trace_print_flags_u64 + *symbol_array); +#endif + +const char *trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr, + unsigned int bitmask_size); + +const char *trace_print_hex_seq(struct trace_seq *p, + const unsigned char *buf, int len, + bool concatenate); + +const char *trace_print_array_seq(struct trace_seq *p, + const void *buf, int count, + size_t el_size); + +struct trace_iterator; +struct trace_event; + +int trace_raw_output_prep(struct trace_iterator *iter, + struct trace_event *event); + +/* + * The trace entry - the most basic unit of tracing. This is what + * is printed in the end as a single line in the trace output, such as: + * + * bash-15816 [01] 235.197585: idle_cpu <- irq_enter + */ +struct trace_entry { + unsigned short type; + unsigned char flags; + unsigned char preempt_count; + int pid; +}; + +#define TRACE_EVENT_TYPE_MAX \ + ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1) + +/* + * Trace iterator - used by printout routines who present trace + * results to users and which routines might sleep, etc: + */ +struct trace_iterator { + struct trace_array *tr; + struct tracer *trace; + struct trace_buffer *trace_buffer; + void *private; + int cpu_file; + struct mutex mutex; + struct ring_buffer_iter **buffer_iter; + unsigned long iter_flags; + + /* trace_seq for __print_flags() and __print_symbolic() etc. */ + struct trace_seq tmp_seq; + + cpumask_var_t started; + + /* it's true when current open file is snapshot */ + bool snapshot; + + /* The below is zeroed out in pipe_read */ + struct trace_seq seq; + struct trace_entry *ent; + unsigned long lost_events; + int leftover; + int ent_size; + int cpu; + u64 ts; + + loff_t pos; + long idx; + + /* All new field here will be zeroed out in pipe_read */ +}; + +enum trace_iter_flags { + TRACE_FILE_LAT_FMT = 1, + TRACE_FILE_ANNOTATE = 2, + TRACE_FILE_TIME_IN_NS = 4, +}; + + +typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter, + int flags, struct trace_event *event); + +struct trace_event_functions { + trace_print_func trace; + trace_print_func raw; + trace_print_func hex; + trace_print_func binary; +}; + +struct trace_event { + struct hlist_node node; + struct list_head list; + int type; + struct trace_event_functions *funcs; +}; + +extern int register_trace_event(struct trace_event *event); +extern int unregister_trace_event(struct trace_event *event); + +/* Return values for print_line callback */ +enum print_line_t { + TRACE_TYPE_PARTIAL_LINE = 0, /* Retry after flushing the seq */ + TRACE_TYPE_HANDLED = 1, + TRACE_TYPE_UNHANDLED = 2, /* Relay to other output functions */ + TRACE_TYPE_NO_CONSUME = 3 /* Handled but ask to not consume */ +}; + +enum print_line_t trace_handle_return(struct trace_seq *s); + +void tracing_generic_entry_update(struct trace_entry *entry, + unsigned long flags, + int pc); +struct trace_event_file; + +struct ring_buffer_event * +trace_event_buffer_lock_reserve(struct ring_buffer **current_buffer, + struct trace_event_file *trace_file, + int type, unsigned long len, + unsigned long flags, int pc); + +#define TRACE_RECORD_CMDLINE BIT(0) +#define TRACE_RECORD_TGID BIT(1) + +void tracing_record_taskinfo(struct task_struct *task, int flags); +void tracing_record_taskinfo_sched_switch(struct task_struct *prev, + struct task_struct *next, int flags); + +void tracing_record_cmdline(struct task_struct *task); +void tracing_record_tgid(struct task_struct *task); + +int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...); + +struct event_filter; + +enum trace_reg { + TRACE_REG_REGISTER, + TRACE_REG_UNREGISTER, +#ifdef CONFIG_PERF_EVENTS + TRACE_REG_PERF_REGISTER, + TRACE_REG_PERF_UNREGISTER, + TRACE_REG_PERF_OPEN, + TRACE_REG_PERF_CLOSE, + /* + * These (ADD/DEL) use a 'boolean' return value, where 1 (true) means a + * custom action was taken and the default action is not to be + * performed. + */ + TRACE_REG_PERF_ADD, + TRACE_REG_PERF_DEL, +#endif +}; + +struct trace_event_call; + +struct trace_event_class { + const char *system; + void *probe; +#ifdef CONFIG_PERF_EVENTS + void *perf_probe; +#endif + int (*reg)(struct trace_event_call *event, + enum trace_reg type, void *data); + int (*define_fields)(struct trace_event_call *); + struct list_head *(*get_fields)(struct trace_event_call *); + struct list_head fields; + int (*raw_init)(struct trace_event_call *); +}; + +extern int trace_event_reg(struct trace_event_call *event, + enum trace_reg type, void *data); + +struct trace_event_buffer { + struct ring_buffer *buffer; + struct ring_buffer_event *event; + struct trace_event_file *trace_file; + void *entry; + unsigned long flags; + int pc; +}; + +void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer, + struct trace_event_file *trace_file, + unsigned long len); + +void trace_event_buffer_commit(struct trace_event_buffer *fbuffer); + +enum { + TRACE_EVENT_FL_FILTERED_BIT, + TRACE_EVENT_FL_CAP_ANY_BIT, + TRACE_EVENT_FL_NO_SET_FILTER_BIT, + TRACE_EVENT_FL_IGNORE_ENABLE_BIT, + TRACE_EVENT_FL_TRACEPOINT_BIT, + TRACE_EVENT_FL_KPROBE_BIT, + TRACE_EVENT_FL_UPROBE_BIT, +}; + +/* + * Event flags: + * FILTERED - The event has a filter attached + * CAP_ANY - Any user can enable for perf + * NO_SET_FILTER - Set when filter has error and is to be ignored + * IGNORE_ENABLE - For trace internal events, do not enable with debugfs file + * TRACEPOINT - Event is a tracepoint + * KPROBE - Event is a kprobe + * UPROBE - Event is a uprobe + */ +enum { + TRACE_EVENT_FL_FILTERED = (1 << TRACE_EVENT_FL_FILTERED_BIT), + TRACE_EVENT_FL_CAP_ANY = (1 << TRACE_EVENT_FL_CAP_ANY_BIT), + TRACE_EVENT_FL_NO_SET_FILTER = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT), + TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT), + TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT), + TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT), + TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT), +}; + +#define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE) + +struct trace_event_call { + struct list_head list; + struct trace_event_class *class; + union { + char *name; + /* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */ + struct tracepoint *tp; + }; + struct trace_event event; + char *print_fmt; + struct event_filter *filter; + void *mod; + void *data; + /* + * bit 0: filter_active + * bit 1: allow trace by non root (cap any) + * bit 2: failed to apply filter + * bit 3: trace internal event (do not enable) + * bit 4: Event was enabled by module + * bit 5: use call filter rather than file filter + * bit 6: Event is a tracepoint + */ + int flags; /* static flags of different events */ + +#ifdef CONFIG_PERF_EVENTS + int perf_refcount; + struct hlist_head __percpu *perf_events; + struct bpf_prog_array __rcu *prog_array; + + int (*perf_perm)(struct trace_event_call *, + struct perf_event *); +#endif +}; + +#ifdef CONFIG_PERF_EVENTS +static inline bool bpf_prog_array_valid(struct trace_event_call *call) +{ + /* + * This inline function checks whether call->prog_array + * is valid or not. The function is called in various places, + * outside rcu_read_lock/unlock, as a heuristic to speed up execution. + * + * If this function returns true, and later call->prog_array + * becomes false inside rcu_read_lock/unlock region, + * we bail out then. If this function return false, + * there is a risk that we might miss a few events if the checking + * were delayed until inside rcu_read_lock/unlock region and + * call->prog_array happened to become non-NULL then. + * + * Here, READ_ONCE() is used instead of rcu_access_pointer(). + * rcu_access_pointer() requires the actual definition of + * "struct bpf_prog_array" while READ_ONCE() only needs + * a declaration of the same type. + */ + return !!READ_ONCE(call->prog_array); +} +#endif + +static inline const char * +trace_event_name(struct trace_event_call *call) +{ + if (call->flags & TRACE_EVENT_FL_TRACEPOINT) + return call->tp ? call->tp->name : NULL; + else + return call->name; +} + +struct trace_array; +struct trace_subsystem_dir; + +enum { + EVENT_FILE_FL_ENABLED_BIT, + EVENT_FILE_FL_RECORDED_CMD_BIT, + EVENT_FILE_FL_RECORDED_TGID_BIT, + EVENT_FILE_FL_FILTERED_BIT, + EVENT_FILE_FL_NO_SET_FILTER_BIT, + EVENT_FILE_FL_SOFT_MODE_BIT, + EVENT_FILE_FL_SOFT_DISABLED_BIT, + EVENT_FILE_FL_TRIGGER_MODE_BIT, + EVENT_FILE_FL_TRIGGER_COND_BIT, + EVENT_FILE_FL_PID_FILTER_BIT, + EVENT_FILE_FL_WAS_ENABLED_BIT, +}; + +/* + * Event file flags: + * ENABLED - The event is enabled + * RECORDED_CMD - The comms should be recorded at sched_switch + * RECORDED_TGID - The tgids should be recorded at sched_switch + * FILTERED - The event has a filter attached + * NO_SET_FILTER - Set when filter has error and is to be ignored + * SOFT_MODE - The event is enabled/disabled by SOFT_DISABLED + * SOFT_DISABLED - When set, do not trace the event (even though its + * tracepoint may be enabled) + * TRIGGER_MODE - When set, invoke the triggers associated with the event + * TRIGGER_COND - When set, one or more triggers has an associated filter + * PID_FILTER - When set, the event is filtered based on pid + * WAS_ENABLED - Set when enabled to know to clear trace on module removal + */ +enum { + EVENT_FILE_FL_ENABLED = (1 << EVENT_FILE_FL_ENABLED_BIT), + EVENT_FILE_FL_RECORDED_CMD = (1 << EVENT_FILE_FL_RECORDED_CMD_BIT), + EVENT_FILE_FL_RECORDED_TGID = (1 << EVENT_FILE_FL_RECORDED_TGID_BIT), + EVENT_FILE_FL_FILTERED = (1 << EVENT_FILE_FL_FILTERED_BIT), + EVENT_FILE_FL_NO_SET_FILTER = (1 << EVENT_FILE_FL_NO_SET_FILTER_BIT), + EVENT_FILE_FL_SOFT_MODE = (1 << EVENT_FILE_FL_SOFT_MODE_BIT), + EVENT_FILE_FL_SOFT_DISABLED = (1 << EVENT_FILE_FL_SOFT_DISABLED_BIT), + EVENT_FILE_FL_TRIGGER_MODE = (1 << EVENT_FILE_FL_TRIGGER_MODE_BIT), + EVENT_FILE_FL_TRIGGER_COND = (1 << EVENT_FILE_FL_TRIGGER_COND_BIT), + EVENT_FILE_FL_PID_FILTER = (1 << EVENT_FILE_FL_PID_FILTER_BIT), + EVENT_FILE_FL_WAS_ENABLED = (1 << EVENT_FILE_FL_WAS_ENABLED_BIT), +}; + +struct trace_event_file { + struct list_head list; + struct trace_event_call *event_call; + struct event_filter __rcu *filter; + struct dentry *dir; + struct trace_array *tr; + struct trace_subsystem_dir *system; + struct list_head triggers; + + /* + * 32 bit flags: + * bit 0: enabled + * bit 1: enabled cmd record + * bit 2: enable/disable with the soft disable bit + * bit 3: soft disabled + * bit 4: trigger enabled + * + * Note: The bits must be set atomically to prevent races + * from other writers. Reads of flags do not need to be in + * sync as they occur in critical sections. But the way flags + * is currently used, these changes do not affect the code + * except that when a change is made, it may have a slight + * delay in propagating the changes to other CPUs due to + * caching and such. Which is mostly OK ;-) + */ + unsigned long flags; + atomic_t sm_ref; /* soft-mode reference counter */ + atomic_t tm_ref; /* trigger-mode reference counter */ +}; + +#define __TRACE_EVENT_FLAGS(name, value) \ + static int __init trace_init_flags_##name(void) \ + { \ + event_##name.flags |= value; \ + return 0; \ + } \ + early_initcall(trace_init_flags_##name); + +#define __TRACE_EVENT_PERF_PERM(name, expr...) \ + static int perf_perm_##name(struct trace_event_call *tp_event, \ + struct perf_event *p_event) \ + { \ + return ({ expr; }); \ + } \ + static int __init trace_init_perf_perm_##name(void) \ + { \ + event_##name.perf_perm = &perf_perm_##name; \ + return 0; \ + } \ + early_initcall(trace_init_perf_perm_##name); + +#define PERF_MAX_TRACE_SIZE 2048 + +#define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */ + +enum event_trigger_type { + ETT_NONE = (0), + ETT_TRACE_ONOFF = (1 << 0), + ETT_SNAPSHOT = (1 << 1), + ETT_STACKTRACE = (1 << 2), + ETT_EVENT_ENABLE = (1 << 3), + ETT_EVENT_HIST = (1 << 4), + ETT_HIST_ENABLE = (1 << 5), +}; + +extern int filter_match_preds(struct event_filter *filter, void *rec); + +extern enum event_trigger_type +event_triggers_call(struct trace_event_file *file, void *rec, + struct ring_buffer_event *event); +extern void +event_triggers_post_call(struct trace_event_file *file, + enum event_trigger_type tt); + +bool trace_event_ignore_this_pid(struct trace_event_file *trace_file); + +/** + * trace_trigger_soft_disabled - do triggers and test if soft disabled + * @file: The file pointer of the event to test + * + * If any triggers without filters are attached to this event, they + * will be called here. If the event is soft disabled and has no + * triggers that require testing the fields, it will return true, + * otherwise false. + */ +static inline bool +trace_trigger_soft_disabled(struct trace_event_file *file) +{ + unsigned long eflags = file->flags; + + if (!(eflags & EVENT_FILE_FL_TRIGGER_COND)) { + if (eflags & EVENT_FILE_FL_TRIGGER_MODE) + event_triggers_call(file, NULL, NULL); + if (eflags & EVENT_FILE_FL_SOFT_DISABLED) + return true; + if (eflags & EVENT_FILE_FL_PID_FILTER) + return trace_event_ignore_this_pid(file); + } + return false; +} + +#ifdef CONFIG_BPF_EVENTS +unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx); +int perf_event_attach_bpf_prog(struct perf_event *event, struct bpf_prog *prog); +void perf_event_detach_bpf_prog(struct perf_event *event); +int perf_event_query_prog_array(struct perf_event *event, void __user *info); +int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog); +int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog); +struct bpf_raw_event_map *bpf_find_raw_tracepoint(const char *name); +int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, + u32 *fd_type, const char **buf, + u64 *probe_offset, u64 *probe_addr); +#else +static inline unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx) +{ + return 1; +} + +static inline int +perf_event_attach_bpf_prog(struct perf_event *event, struct bpf_prog *prog) +{ + return -EOPNOTSUPP; +} + +static inline void perf_event_detach_bpf_prog(struct perf_event *event) { } + +static inline int +perf_event_query_prog_array(struct perf_event *event, void __user *info) +{ + return -EOPNOTSUPP; +} +static inline int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *p) +{ + return -EOPNOTSUPP; +} +static inline int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *p) +{ + return -EOPNOTSUPP; +} +static inline struct bpf_raw_event_map *bpf_find_raw_tracepoint(const char *name) +{ + return NULL; +} +static inline int bpf_get_perf_event_info(const struct perf_event *event, + u32 *prog_id, u32 *fd_type, + const char **buf, u64 *probe_offset, + u64 *probe_addr) +{ + return -EOPNOTSUPP; +} +#endif + +enum { + FILTER_OTHER = 0, + FILTER_STATIC_STRING, + FILTER_DYN_STRING, + FILTER_PTR_STRING, + FILTER_TRACE_FN, + FILTER_COMM, + FILTER_CPU, +}; + +extern int trace_event_raw_init(struct trace_event_call *call); +extern int trace_define_field(struct trace_event_call *call, const char *type, + const char *name, int offset, int size, + int is_signed, int filter_type); +extern int trace_add_event_call_nolock(struct trace_event_call *call); +extern int trace_remove_event_call_nolock(struct trace_event_call *call); +extern int trace_add_event_call(struct trace_event_call *call); +extern int trace_remove_event_call(struct trace_event_call *call); +extern int trace_event_get_offsets(struct trace_event_call *call); + +#define is_signed_type(type) (((type)(-1)) < (type)1) + +int trace_set_clr_event(const char *system, const char *event, int set); + +/* + * The double __builtin_constant_p is because gcc will give us an error + * if we try to allocate the static variable to fmt if it is not a + * constant. Even with the outer if statement optimizing out. + */ +#define event_trace_printk(ip, fmt, args...) \ +do { \ + __trace_printk_check_format(fmt, ##args); \ + tracing_record_cmdline(current); \ + if (__builtin_constant_p(fmt)) { \ + static const char *trace_printk_fmt \ + __attribute__((section("__trace_printk_fmt"))) = \ + __builtin_constant_p(fmt) ? fmt : NULL; \ + \ + __trace_bprintk(ip, trace_printk_fmt, ##args); \ + } else \ + __trace_printk(ip, fmt, ##args); \ +} while (0) + +#ifdef CONFIG_PERF_EVENTS +struct perf_event; + +DECLARE_PER_CPU(struct pt_regs, perf_trace_regs); +DECLARE_PER_CPU(int, bpf_kprobe_override); + +extern int perf_trace_init(struct perf_event *event); +extern void perf_trace_destroy(struct perf_event *event); +extern int perf_trace_add(struct perf_event *event, int flags); +extern void perf_trace_del(struct perf_event *event, int flags); +#ifdef CONFIG_KPROBE_EVENTS +extern int perf_kprobe_init(struct perf_event *event, bool is_retprobe); +extern void perf_kprobe_destroy(struct perf_event *event); +extern int bpf_get_kprobe_info(const struct perf_event *event, + u32 *fd_type, const char **symbol, + u64 *probe_offset, u64 *probe_addr, + bool perf_type_tracepoint); +#endif +#ifdef CONFIG_UPROBE_EVENTS +extern int perf_uprobe_init(struct perf_event *event, bool is_retprobe); +extern void perf_uprobe_destroy(struct perf_event *event); +extern int bpf_get_uprobe_info(const struct perf_event *event, + u32 *fd_type, const char **filename, + u64 *probe_offset, bool perf_type_tracepoint); +#endif +extern int ftrace_profile_set_filter(struct perf_event *event, int event_id, + char *filter_str); +extern void ftrace_profile_free_filter(struct perf_event *event); +void perf_trace_buf_update(void *record, u16 type); +void *perf_trace_buf_alloc(int size, struct pt_regs **regs, int *rctxp); + +void bpf_trace_run1(struct bpf_prog *prog, u64 arg1); +void bpf_trace_run2(struct bpf_prog *prog, u64 arg1, u64 arg2); +void bpf_trace_run3(struct bpf_prog *prog, u64 arg1, u64 arg2, + u64 arg3); +void bpf_trace_run4(struct bpf_prog *prog, u64 arg1, u64 arg2, + u64 arg3, u64 arg4); +void bpf_trace_run5(struct bpf_prog *prog, u64 arg1, u64 arg2, + u64 arg3, u64 arg4, u64 arg5); +void bpf_trace_run6(struct bpf_prog *prog, u64 arg1, u64 arg2, + u64 arg3, u64 arg4, u64 arg5, u64 arg6); +void bpf_trace_run7(struct bpf_prog *prog, u64 arg1, u64 arg2, + u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7); +void bpf_trace_run8(struct bpf_prog *prog, u64 arg1, u64 arg2, + u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7, + u64 arg8); +void bpf_trace_run9(struct bpf_prog *prog, u64 arg1, u64 arg2, + u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7, + u64 arg8, u64 arg9); +void bpf_trace_run10(struct bpf_prog *prog, u64 arg1, u64 arg2, + u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7, + u64 arg8, u64 arg9, u64 arg10); +void bpf_trace_run11(struct bpf_prog *prog, u64 arg1, u64 arg2, + u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7, + u64 arg8, u64 arg9, u64 arg10, u64 arg11); +void bpf_trace_run12(struct bpf_prog *prog, u64 arg1, u64 arg2, + u64 arg3, u64 arg4, u64 arg5, u64 arg6, u64 arg7, + u64 arg8, u64 arg9, u64 arg10, u64 arg11, u64 arg12); +void perf_trace_run_bpf_submit(void *raw_data, int size, int rctx, + struct trace_event_call *call, u64 count, + struct pt_regs *regs, struct hlist_head *head, + struct task_struct *task); + +static inline void +perf_trace_buf_submit(void *raw_data, int size, int rctx, u16 type, + u64 count, struct pt_regs *regs, void *head, + struct task_struct *task) +{ + perf_tp_event(type, count, raw_data, size, regs, head, rctx, task); +} + +#endif + +#endif /* _LINUX_TRACE_EVENT_H */ |