swh:1:snp:c3bf2749e3476071fa748f67b0ffa2fdc5fe49d9
Tip revision: e21a712a9685488f5ce80495b37b9fdbe96c230d authored by Linus Torvalds on 05 August 2019, 01:40:12 UTC
Linux 5.3-rc3
Linux 5.3-rc3
Tip revision: e21a712
trace_events.h
/* 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 short type,
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;
}
static inline struct list_head *
trace_get_fields(struct trace_event_call *event_call)
{
if (!event_call->class->get_fields)
return &event_call->class->fields;
return event_call->class->get_fields(event_call);
}
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_get_raw_tracepoint(const char *name);
void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp);
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_get_raw_tracepoint(const char *name)
{
return NULL;
}
static inline void bpf_put_raw_tracepoint(struct bpf_raw_event_map *btp)
{
}
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(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,
unsigned long ref_ctr_offset, 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 */