linux/kernel/trace/trace.h
Tom Zanussi 067fe038e7 tracing: Add variable reference handling to hist triggers
Add the necessary infrastructure to allow the variables defined on one
event to be referenced in another.  This allows variables set by a
previous event to be referenced and used in expressions combining the
variable values saved by that previous event and the event fields of
the current event.  For example, here's how a latency can be
calculated and saved into yet another variable named 'wakeup_lat':

    # echo 'hist:keys=pid,prio:ts0=common_timestamp ...
    # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp-$ts0 ...

In the first event, the event's timetamp is saved into the variable
ts0.  In the next line, ts0 is subtracted from the second event's
timestamp to produce the latency.

Further users of variable references will be described in subsequent
patches, such as for instance how the 'wakeup_lat' variable above can
be displayed in a latency histogram.

Link: http://lkml.kernel.org/r/b1d3e6975374e34d501ff417c20189c3f9b2c7b8.1516069914.git.tom.zanussi@linux.intel.com

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-03-10 16:05:58 -05:00

1827 lines
57 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_KERNEL_TRACE_H
#define _LINUX_KERNEL_TRACE_H
#include <linux/fs.h>
#include <linux/atomic.h>
#include <linux/sched.h>
#include <linux/clocksource.h>
#include <linux/ring_buffer.h>
#include <linux/mmiotrace.h>
#include <linux/tracepoint.h>
#include <linux/ftrace.h>
#include <linux/hw_breakpoint.h>
#include <linux/trace_seq.h>
#include <linux/trace_events.h>
#include <linux/compiler.h>
#include <linux/trace_seq.h>
#include <linux/glob.h>
#ifdef CONFIG_FTRACE_SYSCALLS
#include <asm/unistd.h> /* For NR_SYSCALLS */
#include <asm/syscall.h> /* some archs define it here */
#endif
enum trace_type {
__TRACE_FIRST_TYPE = 0,
TRACE_FN,
TRACE_CTX,
TRACE_WAKE,
TRACE_STACK,
TRACE_PRINT,
TRACE_BPRINT,
TRACE_MMIO_RW,
TRACE_MMIO_MAP,
TRACE_BRANCH,
TRACE_GRAPH_RET,
TRACE_GRAPH_ENT,
TRACE_USER_STACK,
TRACE_BLK,
TRACE_BPUTS,
TRACE_HWLAT,
TRACE_RAW_DATA,
__TRACE_LAST_TYPE,
};
#undef __field
#define __field(type, item) type item;
#undef __field_struct
#define __field_struct(type, item) __field(type, item)
#undef __field_desc
#define __field_desc(type, container, item)
#undef __array
#define __array(type, item, size) type item[size];
#undef __array_desc
#define __array_desc(type, container, item, size)
#undef __dynamic_array
#define __dynamic_array(type, item) type item[];
#undef F_STRUCT
#define F_STRUCT(args...) args
#undef FTRACE_ENTRY
#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \
struct struct_name { \
struct trace_entry ent; \
tstruct \
}
#undef FTRACE_ENTRY_DUP
#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter)
#undef FTRACE_ENTRY_REG
#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \
filter, regfn) \
FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
filter)
#undef FTRACE_ENTRY_PACKED
#define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print, \
filter) \
FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
filter) __packed
#include "trace_entries.h"
/*
* syscalls are special, and need special handling, this is why
* they are not included in trace_entries.h
*/
struct syscall_trace_enter {
struct trace_entry ent;
int nr;
unsigned long args[];
};
struct syscall_trace_exit {
struct trace_entry ent;
int nr;
long ret;
};
struct kprobe_trace_entry_head {
struct trace_entry ent;
unsigned long ip;
};
struct kretprobe_trace_entry_head {
struct trace_entry ent;
unsigned long func;
unsigned long ret_ip;
};
/*
* trace_flag_type is an enumeration that holds different
* states when a trace occurs. These are:
* IRQS_OFF - interrupts were disabled
* IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
* NEED_RESCHED - reschedule is requested
* HARDIRQ - inside an interrupt handler
* SOFTIRQ - inside a softirq handler
*/
enum trace_flag_type {
TRACE_FLAG_IRQS_OFF = 0x01,
TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
TRACE_FLAG_NEED_RESCHED = 0x04,
TRACE_FLAG_HARDIRQ = 0x08,
TRACE_FLAG_SOFTIRQ = 0x10,
TRACE_FLAG_PREEMPT_RESCHED = 0x20,
TRACE_FLAG_NMI = 0x40,
};
#define TRACE_BUF_SIZE 1024
struct trace_array;
/*
* The CPU trace array - it consists of thousands of trace entries
* plus some other descriptor data: (for example which task started
* the trace, etc.)
*/
struct trace_array_cpu {
atomic_t disabled;
void *buffer_page; /* ring buffer spare */
unsigned long entries;
unsigned long saved_latency;
unsigned long critical_start;
unsigned long critical_end;
unsigned long critical_sequence;
unsigned long nice;
unsigned long policy;
unsigned long rt_priority;
unsigned long skipped_entries;
u64 preempt_timestamp;
pid_t pid;
kuid_t uid;
char comm[TASK_COMM_LEN];
bool ignore_pid;
#ifdef CONFIG_FUNCTION_TRACER
bool ftrace_ignore_pid;
#endif
};
struct tracer;
struct trace_option_dentry;
struct trace_buffer {
struct trace_array *tr;
struct ring_buffer *buffer;
struct trace_array_cpu __percpu *data;
u64 time_start;
int cpu;
};
#define TRACE_FLAGS_MAX_SIZE 32
struct trace_options {
struct tracer *tracer;
struct trace_option_dentry *topts;
};
struct trace_pid_list {
int pid_max;
unsigned long *pids;
};
/*
* The trace array - an array of per-CPU trace arrays. This is the
* highest level data structure that individual tracers deal with.
* They have on/off state as well:
*/
struct trace_array {
struct list_head list;
char *name;
struct trace_buffer trace_buffer;
#ifdef CONFIG_TRACER_MAX_TRACE
/*
* The max_buffer is used to snapshot the trace when a maximum
* latency is reached, or when the user initiates a snapshot.
* Some tracers will use this to store a maximum trace while
* it continues examining live traces.
*
* The buffers for the max_buffer are set up the same as the trace_buffer
* When a snapshot is taken, the buffer of the max_buffer is swapped
* with the buffer of the trace_buffer and the buffers are reset for
* the trace_buffer so the tracing can continue.
*/
struct trace_buffer max_buffer;
bool allocated_snapshot;
#endif
#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
unsigned long max_latency;
#endif
struct trace_pid_list __rcu *filtered_pids;
/*
* max_lock is used to protect the swapping of buffers
* when taking a max snapshot. The buffers themselves are
* protected by per_cpu spinlocks. But the action of the swap
* needs its own lock.
*
* This is defined as a arch_spinlock_t in order to help
* with performance when lockdep debugging is enabled.
*
* It is also used in other places outside the update_max_tr
* so it needs to be defined outside of the
* CONFIG_TRACER_MAX_TRACE.
*/
arch_spinlock_t max_lock;
int buffer_disabled;
#ifdef CONFIG_FTRACE_SYSCALLS
int sys_refcount_enter;
int sys_refcount_exit;
struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
#endif
int stop_count;
int clock_id;
int nr_topts;
bool clear_trace;
struct tracer *current_trace;
unsigned int trace_flags;
unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE];
unsigned int flags;
raw_spinlock_t start_lock;
struct dentry *dir;
struct dentry *options;
struct dentry *percpu_dir;
struct dentry *event_dir;
struct trace_options *topts;
struct list_head systems;
struct list_head events;
cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
int ref;
#ifdef CONFIG_FUNCTION_TRACER
struct ftrace_ops *ops;
struct trace_pid_list __rcu *function_pids;
#ifdef CONFIG_DYNAMIC_FTRACE
/* All of these are protected by the ftrace_lock */
struct list_head func_probes;
struct list_head mod_trace;
struct list_head mod_notrace;
#endif
/* function tracing enabled */
int function_enabled;
#endif
int time_stamp_abs_ref;
struct list_head hist_vars;
};
enum {
TRACE_ARRAY_FL_GLOBAL = (1 << 0)
};
extern struct list_head ftrace_trace_arrays;
extern struct mutex trace_types_lock;
extern int trace_array_get(struct trace_array *tr);
extern void trace_array_put(struct trace_array *tr);
extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs);
extern bool trace_clock_in_ns(struct trace_array *tr);
/*
* The global tracer (top) should be the first trace array added,
* but we check the flag anyway.
*/
static inline struct trace_array *top_trace_array(void)
{
struct trace_array *tr;
if (list_empty(&ftrace_trace_arrays))
return NULL;
tr = list_entry(ftrace_trace_arrays.prev,
typeof(*tr), list);
WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
return tr;
}
#define FTRACE_CMP_TYPE(var, type) \
__builtin_types_compatible_p(typeof(var), type *)
#undef IF_ASSIGN
#define IF_ASSIGN(var, entry, etype, id) \
if (FTRACE_CMP_TYPE(var, etype)) { \
var = (typeof(var))(entry); \
WARN_ON(id && (entry)->type != id); \
break; \
}
/* Will cause compile errors if type is not found. */
extern void __ftrace_bad_type(void);
/*
* The trace_assign_type is a verifier that the entry type is
* the same as the type being assigned. To add new types simply
* add a line with the following format:
*
* IF_ASSIGN(var, ent, type, id);
*
* Where "type" is the trace type that includes the trace_entry
* as the "ent" item. And "id" is the trace identifier that is
* used in the trace_type enum.
*
* If the type can have more than one id, then use zero.
*/
#define trace_assign_type(var, ent) \
do { \
IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS); \
IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT); \
IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
TRACE_MMIO_RW); \
IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
TRACE_MMIO_MAP); \
IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
TRACE_GRAPH_ENT); \
IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
TRACE_GRAPH_RET); \
__ftrace_bad_type(); \
} while (0)
/*
* An option specific to a tracer. This is a boolean value.
* The bit is the bit index that sets its value on the
* flags value in struct tracer_flags.
*/
struct tracer_opt {
const char *name; /* Will appear on the trace_options file */
u32 bit; /* Mask assigned in val field in tracer_flags */
};
/*
* The set of specific options for a tracer. Your tracer
* have to set the initial value of the flags val.
*/
struct tracer_flags {
u32 val;
struct tracer_opt *opts;
struct tracer *trace;
};
/* Makes more easy to define a tracer opt */
#define TRACER_OPT(s, b) .name = #s, .bit = b
struct trace_option_dentry {
struct tracer_opt *opt;
struct tracer_flags *flags;
struct trace_array *tr;
struct dentry *entry;
};
/**
* struct tracer - a specific tracer and its callbacks to interact with tracefs
* @name: the name chosen to select it on the available_tracers file
* @init: called when one switches to this tracer (echo name > current_tracer)
* @reset: called when one switches to another tracer
* @start: called when tracing is unpaused (echo 1 > tracing_on)
* @stop: called when tracing is paused (echo 0 > tracing_on)
* @update_thresh: called when tracing_thresh is updated
* @open: called when the trace file is opened
* @pipe_open: called when the trace_pipe file is opened
* @close: called when the trace file is released
* @pipe_close: called when the trace_pipe file is released
* @read: override the default read callback on trace_pipe
* @splice_read: override the default splice_read callback on trace_pipe
* @selftest: selftest to run on boot (see trace_selftest.c)
* @print_headers: override the first lines that describe your columns
* @print_line: callback that prints a trace
* @set_flag: signals one of your private flags changed (trace_options file)
* @flags: your private flags
*/
struct tracer {
const char *name;
int (*init)(struct trace_array *tr);
void (*reset)(struct trace_array *tr);
void (*start)(struct trace_array *tr);
void (*stop)(struct trace_array *tr);
int (*update_thresh)(struct trace_array *tr);
void (*open)(struct trace_iterator *iter);
void (*pipe_open)(struct trace_iterator *iter);
void (*close)(struct trace_iterator *iter);
void (*pipe_close)(struct trace_iterator *iter);
ssize_t (*read)(struct trace_iterator *iter,
struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos);
ssize_t (*splice_read)(struct trace_iterator *iter,
struct file *filp,
loff_t *ppos,
struct pipe_inode_info *pipe,
size_t len,
unsigned int flags);
#ifdef CONFIG_FTRACE_STARTUP_TEST
int (*selftest)(struct tracer *trace,
struct trace_array *tr);
#endif
void (*print_header)(struct seq_file *m);
enum print_line_t (*print_line)(struct trace_iterator *iter);
/* If you handled the flag setting, return 0 */
int (*set_flag)(struct trace_array *tr,
u32 old_flags, u32 bit, int set);
/* Return 0 if OK with change, else return non-zero */
int (*flag_changed)(struct trace_array *tr,
u32 mask, int set);
struct tracer *next;
struct tracer_flags *flags;
int enabled;
int ref;
bool print_max;
bool allow_instances;
#ifdef CONFIG_TRACER_MAX_TRACE
bool use_max_tr;
#endif
/* True if tracer cannot be enabled in kernel param */
bool noboot;
};
/* Only current can touch trace_recursion */
/*
* For function tracing recursion:
* The order of these bits are important.
*
* When function tracing occurs, the following steps are made:
* If arch does not support a ftrace feature:
* call internal function (uses INTERNAL bits) which calls...
* If callback is registered to the "global" list, the list
* function is called and recursion checks the GLOBAL bits.
* then this function calls...
* The function callback, which can use the FTRACE bits to
* check for recursion.
*
* Now if the arch does not suppport a feature, and it calls
* the global list function which calls the ftrace callback
* all three of these steps will do a recursion protection.
* There's no reason to do one if the previous caller already
* did. The recursion that we are protecting against will
* go through the same steps again.
*
* To prevent the multiple recursion checks, if a recursion
* bit is set that is higher than the MAX bit of the current
* check, then we know that the check was made by the previous
* caller, and we can skip the current check.
*/
enum {
TRACE_BUFFER_BIT,
TRACE_BUFFER_NMI_BIT,
TRACE_BUFFER_IRQ_BIT,
TRACE_BUFFER_SIRQ_BIT,
/* Start of function recursion bits */
TRACE_FTRACE_BIT,
TRACE_FTRACE_NMI_BIT,
TRACE_FTRACE_IRQ_BIT,
TRACE_FTRACE_SIRQ_BIT,
/* INTERNAL_BITs must be greater than FTRACE_BITs */
TRACE_INTERNAL_BIT,
TRACE_INTERNAL_NMI_BIT,
TRACE_INTERNAL_IRQ_BIT,
TRACE_INTERNAL_SIRQ_BIT,
TRACE_BRANCH_BIT,
/*
* Abuse of the trace_recursion.
* As we need a way to maintain state if we are tracing the function
* graph in irq because we want to trace a particular function that
* was called in irq context but we have irq tracing off. Since this
* can only be modified by current, we can reuse trace_recursion.
*/
TRACE_IRQ_BIT,
};
#define trace_recursion_set(bit) do { (current)->trace_recursion |= (1<<(bit)); } while (0)
#define trace_recursion_clear(bit) do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
#define trace_recursion_test(bit) ((current)->trace_recursion & (1<<(bit)))
#define TRACE_CONTEXT_BITS 4
#define TRACE_FTRACE_START TRACE_FTRACE_BIT
#define TRACE_FTRACE_MAX ((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)
#define TRACE_LIST_START TRACE_INTERNAL_BIT
#define TRACE_LIST_MAX ((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
#define TRACE_CONTEXT_MASK TRACE_LIST_MAX
static __always_inline int trace_get_context_bit(void)
{
int bit;
if (in_interrupt()) {
if (in_nmi())
bit = 0;
else if (in_irq())
bit = 1;
else
bit = 2;
} else
bit = 3;
return bit;
}
static __always_inline int trace_test_and_set_recursion(int start, int max)
{
unsigned int val = current->trace_recursion;
int bit;
/* A previous recursion check was made */
if ((val & TRACE_CONTEXT_MASK) > max)
return 0;
bit = trace_get_context_bit() + start;
if (unlikely(val & (1 << bit)))
return -1;
val |= 1 << bit;
current->trace_recursion = val;
barrier();
return bit;
}
static __always_inline void trace_clear_recursion(int bit)
{
unsigned int val = current->trace_recursion;
if (!bit)
return;
bit = 1 << bit;
val &= ~bit;
barrier();
current->trace_recursion = val;
}
static inline struct ring_buffer_iter *
trace_buffer_iter(struct trace_iterator *iter, int cpu)
{
if (iter->buffer_iter && iter->buffer_iter[cpu])
return iter->buffer_iter[cpu];
return NULL;
}
int tracer_init(struct tracer *t, struct trace_array *tr);
int tracing_is_enabled(void);
void tracing_reset(struct trace_buffer *buf, int cpu);
void tracing_reset_online_cpus(struct trace_buffer *buf);
void tracing_reset_current(int cpu);
void tracing_reset_all_online_cpus(void);
int tracing_open_generic(struct inode *inode, struct file *filp);
bool tracing_is_disabled(void);
int tracer_tracing_is_on(struct trace_array *tr);
void tracer_tracing_on(struct trace_array *tr);
void tracer_tracing_off(struct trace_array *tr);
struct dentry *trace_create_file(const char *name,
umode_t mode,
struct dentry *parent,
void *data,
const struct file_operations *fops);
struct dentry *tracing_init_dentry(void);
struct ring_buffer_event;
struct ring_buffer_event *
trace_buffer_lock_reserve(struct ring_buffer *buffer,
int type,
unsigned long len,
unsigned long flags,
int pc);
struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
struct trace_array_cpu *data);
struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
int *ent_cpu, u64 *ent_ts);
void trace_buffer_unlock_commit_nostack(struct ring_buffer *buffer,
struct ring_buffer_event *event);
int trace_empty(struct trace_iterator *iter);
void *trace_find_next_entry_inc(struct trace_iterator *iter);
void trace_init_global_iter(struct trace_iterator *iter);
void tracing_iter_reset(struct trace_iterator *iter, int cpu);
void trace_function(struct trace_array *tr,
unsigned long ip,
unsigned long parent_ip,
unsigned long flags, int pc);
void trace_graph_function(struct trace_array *tr,
unsigned long ip,
unsigned long parent_ip,
unsigned long flags, int pc);
void trace_latency_header(struct seq_file *m);
void trace_default_header(struct seq_file *m);
void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
int trace_empty(struct trace_iterator *iter);
void trace_graph_return(struct ftrace_graph_ret *trace);
int trace_graph_entry(struct ftrace_graph_ent *trace);
void set_graph_array(struct trace_array *tr);
void tracing_start_cmdline_record(void);
void tracing_stop_cmdline_record(void);
void tracing_start_tgid_record(void);
void tracing_stop_tgid_record(void);
int register_tracer(struct tracer *type);
int is_tracing_stopped(void);
loff_t tracing_lseek(struct file *file, loff_t offset, int whence);
extern cpumask_var_t __read_mostly tracing_buffer_mask;
#define for_each_tracing_cpu(cpu) \
for_each_cpu(cpu, tracing_buffer_mask)
extern unsigned long nsecs_to_usecs(unsigned long nsecs);
extern unsigned long tracing_thresh;
/* PID filtering */
extern int pid_max;
bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
pid_t search_pid);
bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,
struct task_struct *task);
void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
struct task_struct *self,
struct task_struct *task);
void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
int trace_pid_show(struct seq_file *m, void *v);
void trace_free_pid_list(struct trace_pid_list *pid_list);
int trace_pid_write(struct trace_pid_list *filtered_pids,
struct trace_pid_list **new_pid_list,
const char __user *ubuf, size_t cnt);
#ifdef CONFIG_TRACER_MAX_TRACE
void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
void update_max_tr_single(struct trace_array *tr,
struct task_struct *tsk, int cpu);
#endif /* CONFIG_TRACER_MAX_TRACE */
#ifdef CONFIG_STACKTRACE
void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
int pc);
void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
int pc);
#else
static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
unsigned long flags, int pc)
{
}
static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
int skip, int pc)
{
}
#endif /* CONFIG_STACKTRACE */
extern u64 ftrace_now(int cpu);
extern void trace_find_cmdline(int pid, char comm[]);
extern int trace_find_tgid(int pid);
extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
#ifdef CONFIG_DYNAMIC_FTRACE
extern unsigned long ftrace_update_tot_cnt;
void ftrace_init_trace_array(struct trace_array *tr);
#else
static inline void ftrace_init_trace_array(struct trace_array *tr) { }
#endif
#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
extern int DYN_FTRACE_TEST_NAME(void);
#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
extern int DYN_FTRACE_TEST_NAME2(void);
extern bool ring_buffer_expanded;
extern bool tracing_selftest_disabled;
#ifdef CONFIG_FTRACE_STARTUP_TEST
extern int trace_selftest_startup_function(struct tracer *trace,
struct trace_array *tr);
extern int trace_selftest_startup_function_graph(struct tracer *trace,
struct trace_array *tr);
extern int trace_selftest_startup_irqsoff(struct tracer *trace,
struct trace_array *tr);
extern int trace_selftest_startup_preemptoff(struct tracer *trace,
struct trace_array *tr);
extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
struct trace_array *tr);
extern int trace_selftest_startup_wakeup(struct tracer *trace,
struct trace_array *tr);
extern int trace_selftest_startup_nop(struct tracer *trace,
struct trace_array *tr);
extern int trace_selftest_startup_branch(struct tracer *trace,
struct trace_array *tr);
/*
* Tracer data references selftest functions that only occur
* on boot up. These can be __init functions. Thus, when selftests
* are enabled, then the tracers need to reference __init functions.
*/
#define __tracer_data __refdata
#else
/* Tracers are seldom changed. Optimize when selftests are disabled. */
#define __tracer_data __read_mostly
#endif /* CONFIG_FTRACE_STARTUP_TEST */
extern void *head_page(struct trace_array_cpu *data);
extern unsigned long long ns2usecs(u64 nsec);
extern int
trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
extern int
trace_vprintk(unsigned long ip, const char *fmt, va_list args);
extern int
trace_array_vprintk(struct trace_array *tr,
unsigned long ip, const char *fmt, va_list args);
int trace_array_printk(struct trace_array *tr,
unsigned long ip, const char *fmt, ...);
int trace_array_printk_buf(struct ring_buffer *buffer,
unsigned long ip, const char *fmt, ...);
void trace_printk_seq(struct trace_seq *s);
enum print_line_t print_trace_line(struct trace_iterator *iter);
extern char trace_find_mark(unsigned long long duration);
struct ftrace_hash;
struct ftrace_mod_load {
struct list_head list;
char *func;
char *module;
int enable;
};
enum {
FTRACE_HASH_FL_MOD = (1 << 0),
};
struct ftrace_hash {
unsigned long size_bits;
struct hlist_head *buckets;
unsigned long count;
unsigned long flags;
struct rcu_head rcu;
};
struct ftrace_func_entry *
ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);
static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
{
return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));
}
/* Standard output formatting function used for function return traces */
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
/* Flag options */
#define TRACE_GRAPH_PRINT_OVERRUN 0x1
#define TRACE_GRAPH_PRINT_CPU 0x2
#define TRACE_GRAPH_PRINT_OVERHEAD 0x4
#define TRACE_GRAPH_PRINT_PROC 0x8
#define TRACE_GRAPH_PRINT_DURATION 0x10
#define TRACE_GRAPH_PRINT_ABS_TIME 0x20
#define TRACE_GRAPH_PRINT_IRQS 0x40
#define TRACE_GRAPH_PRINT_TAIL 0x80
#define TRACE_GRAPH_SLEEP_TIME 0x100
#define TRACE_GRAPH_GRAPH_TIME 0x200
#define TRACE_GRAPH_PRINT_FILL_SHIFT 28
#define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
extern void ftrace_graph_sleep_time_control(bool enable);
extern void ftrace_graph_graph_time_control(bool enable);
extern enum print_line_t
print_graph_function_flags(struct trace_iterator *iter, u32 flags);
extern void print_graph_headers_flags(struct seq_file *s, u32 flags);
extern void
trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
extern void graph_trace_open(struct trace_iterator *iter);
extern void graph_trace_close(struct trace_iterator *iter);
extern int __trace_graph_entry(struct trace_array *tr,
struct ftrace_graph_ent *trace,
unsigned long flags, int pc);
extern void __trace_graph_return(struct trace_array *tr,
struct ftrace_graph_ret *trace,
unsigned long flags, int pc);
#ifdef CONFIG_DYNAMIC_FTRACE
extern struct ftrace_hash *ftrace_graph_hash;
extern struct ftrace_hash *ftrace_graph_notrace_hash;
static inline int ftrace_graph_addr(unsigned long addr)
{
int ret = 0;
preempt_disable_notrace();
if (ftrace_hash_empty(ftrace_graph_hash)) {
ret = 1;
goto out;
}
if (ftrace_lookup_ip(ftrace_graph_hash, addr)) {
/*
* If no irqs are to be traced, but a set_graph_function
* is set, and called by an interrupt handler, we still
* want to trace it.
*/
if (in_irq())
trace_recursion_set(TRACE_IRQ_BIT);
else
trace_recursion_clear(TRACE_IRQ_BIT);
ret = 1;
}
out:
preempt_enable_notrace();
return ret;
}
static inline int ftrace_graph_notrace_addr(unsigned long addr)
{
int ret = 0;
preempt_disable_notrace();
if (ftrace_lookup_ip(ftrace_graph_notrace_hash, addr))
ret = 1;
preempt_enable_notrace();
return ret;
}
#else
static inline int ftrace_graph_addr(unsigned long addr)
{
return 1;
}
static inline int ftrace_graph_notrace_addr(unsigned long addr)
{
return 0;
}
#endif /* CONFIG_DYNAMIC_FTRACE */
extern unsigned int fgraph_max_depth;
static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
{
/* trace it when it is-nested-in or is a function enabled. */
return !(trace->depth || ftrace_graph_addr(trace->func)) ||
(trace->depth < 0) ||
(fgraph_max_depth && trace->depth >= fgraph_max_depth);
}
#else /* CONFIG_FUNCTION_GRAPH_TRACER */
static inline enum print_line_t
print_graph_function_flags(struct trace_iterator *iter, u32 flags)
{
return TRACE_TYPE_UNHANDLED;
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
extern struct list_head ftrace_pids;
#ifdef CONFIG_FUNCTION_TRACER
struct ftrace_func_command {
struct list_head list;
char *name;
int (*func)(struct trace_array *tr,
struct ftrace_hash *hash,
char *func, char *cmd,
char *params, int enable);
};
extern bool ftrace_filter_param __initdata;
static inline int ftrace_trace_task(struct trace_array *tr)
{
return !this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid);
}
extern int ftrace_is_dead(void);
int ftrace_create_function_files(struct trace_array *tr,
struct dentry *parent);
void ftrace_destroy_function_files(struct trace_array *tr);
void ftrace_init_global_array_ops(struct trace_array *tr);
void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
void ftrace_reset_array_ops(struct trace_array *tr);
int using_ftrace_ops_list_func(void);
void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
void ftrace_init_tracefs_toplevel(struct trace_array *tr,
struct dentry *d_tracer);
void ftrace_clear_pids(struct trace_array *tr);
int init_function_trace(void);
void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
#else
static inline int ftrace_trace_task(struct trace_array *tr)
{
return 1;
}
static inline int ftrace_is_dead(void) { return 0; }
static inline int
ftrace_create_function_files(struct trace_array *tr,
struct dentry *parent)
{
return 0;
}
static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
static inline __init void
ftrace_init_global_array_ops(struct trace_array *tr) { }
static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
static inline void ftrace_clear_pids(struct trace_array *tr) { }
static inline int init_function_trace(void) { return 0; }
static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
/* ftace_func_t type is not defined, use macro instead of static inline */
#define ftrace_init_array_ops(tr, func) do { } while (0)
#endif /* CONFIG_FUNCTION_TRACER */
#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
struct ftrace_probe_ops {
void (*func)(unsigned long ip,
unsigned long parent_ip,
struct trace_array *tr,
struct ftrace_probe_ops *ops,
void *data);
int (*init)(struct ftrace_probe_ops *ops,
struct trace_array *tr,
unsigned long ip, void *init_data,
void **data);
void (*free)(struct ftrace_probe_ops *ops,
struct trace_array *tr,
unsigned long ip, void *data);
int (*print)(struct seq_file *m,
unsigned long ip,
struct ftrace_probe_ops *ops,
void *data);
};
struct ftrace_func_mapper;
typedef int (*ftrace_mapper_func)(void *data);
struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
unsigned long ip);
int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
unsigned long ip, void *data);
void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
unsigned long ip);
void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
ftrace_mapper_func free_func);
extern int
register_ftrace_function_probe(char *glob, struct trace_array *tr,
struct ftrace_probe_ops *ops, void *data);
extern int
unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
struct ftrace_probe_ops *ops);
extern void clear_ftrace_function_probes(struct trace_array *tr);
int register_ftrace_command(struct ftrace_func_command *cmd);
int unregister_ftrace_command(struct ftrace_func_command *cmd);
void ftrace_create_filter_files(struct ftrace_ops *ops,
struct dentry *parent);
void ftrace_destroy_filter_files(struct ftrace_ops *ops);
#else
struct ftrace_func_command;
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 void clear_ftrace_function_probes(struct trace_array *tr)
{
}
/*
* The ops parameter passed in is usually undefined.
* This must be a macro.
*/
#define ftrace_create_filter_files(ops, parent) do { } while (0)
#define ftrace_destroy_filter_files(ops) do { } while (0)
#endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */
bool ftrace_event_is_function(struct trace_event_call *call);
/*
* struct trace_parser - servers for reading the user input separated by spaces
* @cont: set if the input is not complete - no final space char was found
* @buffer: holds the parsed user input
* @idx: user input length
* @size: buffer size
*/
struct trace_parser {
bool cont;
char *buffer;
unsigned idx;
unsigned size;
};
static inline bool trace_parser_loaded(struct trace_parser *parser)
{
return (parser->idx != 0);
}
static inline bool trace_parser_cont(struct trace_parser *parser)
{
return parser->cont;
}
static inline void trace_parser_clear(struct trace_parser *parser)
{
parser->cont = false;
parser->idx = 0;
}
extern int trace_parser_get_init(struct trace_parser *parser, int size);
extern void trace_parser_put(struct trace_parser *parser);
extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
size_t cnt, loff_t *ppos);
/*
* Only create function graph options if function graph is configured.
*/
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
# define FGRAPH_FLAGS \
C(DISPLAY_GRAPH, "display-graph"),
#else
# define FGRAPH_FLAGS
#endif
#ifdef CONFIG_BRANCH_TRACER
# define BRANCH_FLAGS \
C(BRANCH, "branch"),
#else
# define BRANCH_FLAGS
#endif
#ifdef CONFIG_FUNCTION_TRACER
# define FUNCTION_FLAGS \
C(FUNCTION, "function-trace"), \
C(FUNC_FORK, "function-fork"),
# define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
#else
# define FUNCTION_FLAGS
# define FUNCTION_DEFAULT_FLAGS 0UL
# define TRACE_ITER_FUNC_FORK 0UL
#endif
#ifdef CONFIG_STACKTRACE
# define STACK_FLAGS \
C(STACKTRACE, "stacktrace"),
#else
# define STACK_FLAGS
#endif
/*
* trace_iterator_flags is an enumeration that defines bit
* positions into trace_flags that controls the output.
*
* NOTE: These bits must match the trace_options array in
* trace.c (this macro guarantees it).
*/
#define TRACE_FLAGS \
C(PRINT_PARENT, "print-parent"), \
C(SYM_OFFSET, "sym-offset"), \
C(SYM_ADDR, "sym-addr"), \
C(VERBOSE, "verbose"), \
C(RAW, "raw"), \
C(HEX, "hex"), \
C(BIN, "bin"), \
C(BLOCK, "block"), \
C(PRINTK, "trace_printk"), \
C(ANNOTATE, "annotate"), \
C(USERSTACKTRACE, "userstacktrace"), \
C(SYM_USEROBJ, "sym-userobj"), \
C(PRINTK_MSGONLY, "printk-msg-only"), \
C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \
C(LATENCY_FMT, "latency-format"), \
C(RECORD_CMD, "record-cmd"), \
C(RECORD_TGID, "record-tgid"), \
C(OVERWRITE, "overwrite"), \
C(STOP_ON_FREE, "disable_on_free"), \
C(IRQ_INFO, "irq-info"), \
C(MARKERS, "markers"), \
C(EVENT_FORK, "event-fork"), \
FUNCTION_FLAGS \
FGRAPH_FLAGS \
STACK_FLAGS \
BRANCH_FLAGS
/*
* By defining C, we can make TRACE_FLAGS a list of bit names
* that will define the bits for the flag masks.
*/
#undef C
#define C(a, b) TRACE_ITER_##a##_BIT
enum trace_iterator_bits {
TRACE_FLAGS
/* Make sure we don't go more than we have bits for */
TRACE_ITER_LAST_BIT
};
/*
* By redefining C, we can make TRACE_FLAGS a list of masks that
* use the bits as defined above.
*/
#undef C
#define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
enum trace_iterator_flags { TRACE_FLAGS };
/*
* TRACE_ITER_SYM_MASK masks the options in trace_flags that
* control the output of kernel symbols.
*/
#define TRACE_ITER_SYM_MASK \
(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)
extern struct tracer nop_trace;
#ifdef CONFIG_BRANCH_TRACER
extern int enable_branch_tracing(struct trace_array *tr);
extern void disable_branch_tracing(void);
static inline int trace_branch_enable(struct trace_array *tr)
{
if (tr->trace_flags & TRACE_ITER_BRANCH)
return enable_branch_tracing(tr);
return 0;
}
static inline void trace_branch_disable(void)
{
/* due to races, always disable */
disable_branch_tracing();
}
#else
static inline int trace_branch_enable(struct trace_array *tr)
{
return 0;
}
static inline void trace_branch_disable(void)
{
}
#endif /* CONFIG_BRANCH_TRACER */
/* set ring buffers to default size if not already done so */
int tracing_update_buffers(void);
struct ftrace_event_field {
struct list_head link;
const char *name;
const char *type;
int filter_type;
int offset;
int size;
int is_signed;
};
struct event_filter {
int n_preds; /* Number assigned */
int a_preds; /* allocated */
struct filter_pred __rcu *preds;
struct filter_pred __rcu *root;
char *filter_string;
};
struct event_subsystem {
struct list_head list;
const char *name;
struct event_filter *filter;
int ref_count;
};
struct trace_subsystem_dir {
struct list_head list;
struct event_subsystem *subsystem;
struct trace_array *tr;
struct dentry *entry;
int ref_count;
int nr_events;
};
extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
struct ring_buffer *buffer,
struct ring_buffer_event *event);
void trace_buffer_unlock_commit_regs(struct trace_array *tr,
struct ring_buffer *buffer,
struct ring_buffer_event *event,
unsigned long flags, int pc,
struct pt_regs *regs);
static inline void trace_buffer_unlock_commit(struct trace_array *tr,
struct ring_buffer *buffer,
struct ring_buffer_event *event,
unsigned long flags, int pc)
{
trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
}
DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
DECLARE_PER_CPU(int, trace_buffered_event_cnt);
void trace_buffered_event_disable(void);
void trace_buffered_event_enable(void);
static inline void
__trace_event_discard_commit(struct ring_buffer *buffer,
struct ring_buffer_event *event)
{
if (this_cpu_read(trace_buffered_event) == event) {
/* Simply release the temp buffer */
this_cpu_dec(trace_buffered_event_cnt);
return;
}
ring_buffer_discard_commit(buffer, event);
}
/*
* Helper function for event_trigger_unlock_commit{_regs}().
* If there are event triggers attached to this event that requires
* filtering against its fields, then they wil be called as the
* entry already holds the field information of the current event.
*
* It also checks if the event should be discarded or not.
* It is to be discarded if the event is soft disabled and the
* event was only recorded to process triggers, or if the event
* filter is active and this event did not match the filters.
*
* Returns true if the event is discarded, false otherwise.
*/
static inline bool
__event_trigger_test_discard(struct trace_event_file *file,
struct ring_buffer *buffer,
struct ring_buffer_event *event,
void *entry,
enum event_trigger_type *tt)
{
unsigned long eflags = file->flags;
if (eflags & EVENT_FILE_FL_TRIGGER_COND)
*tt = event_triggers_call(file, entry, event);
if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
(unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
!filter_match_preds(file->filter, entry))) {
__trace_event_discard_commit(buffer, event);
return true;
}
return false;
}
/**
* event_trigger_unlock_commit - handle triggers and finish event commit
* @file: The file pointer assoctiated to the event
* @buffer: The ring buffer that the event is being written to
* @event: The event meta data in the ring buffer
* @entry: The event itself
* @irq_flags: The state of the interrupts at the start of the event
* @pc: The state of the preempt count at the start of the event.
*
* This is a helper function to handle triggers that require data
* from the event itself. It also tests the event against filters and
* if the event is soft disabled and should be discarded.
*/
static inline void
event_trigger_unlock_commit(struct trace_event_file *file,
struct ring_buffer *buffer,
struct ring_buffer_event *event,
void *entry, unsigned long irq_flags, int pc)
{
enum event_trigger_type tt = ETT_NONE;
if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);
if (tt)
event_triggers_post_call(file, tt, entry, event);
}
/**
* event_trigger_unlock_commit_regs - handle triggers and finish event commit
* @file: The file pointer assoctiated to the event
* @buffer: The ring buffer that the event is being written to
* @event: The event meta data in the ring buffer
* @entry: The event itself
* @irq_flags: The state of the interrupts at the start of the event
* @pc: The state of the preempt count at the start of the event.
*
* This is a helper function to handle triggers that require data
* from the event itself. It also tests the event against filters and
* if the event is soft disabled and should be discarded.
*
* Same as event_trigger_unlock_commit() but calls
* trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
*/
static inline void
event_trigger_unlock_commit_regs(struct trace_event_file *file,
struct ring_buffer *buffer,
struct ring_buffer_event *event,
void *entry, unsigned long irq_flags, int pc,
struct pt_regs *regs)
{
enum event_trigger_type tt = ETT_NONE;
if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
trace_buffer_unlock_commit_regs(file->tr, buffer, event,
irq_flags, pc, regs);
if (tt)
event_triggers_post_call(file, tt, entry, event);
}
#define FILTER_PRED_INVALID ((unsigned short)-1)
#define FILTER_PRED_IS_RIGHT (1 << 15)
#define FILTER_PRED_FOLD (1 << 15)
/*
* The max preds is the size of unsigned short with
* two flags at the MSBs. One bit is used for both the IS_RIGHT
* and FOLD flags. The other is reserved.
*
* 2^14 preds is way more than enough.
*/
#define MAX_FILTER_PRED 16384
struct filter_pred;
struct regex;
typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
typedef int (*regex_match_func)(char *str, struct regex *r, int len);
enum regex_type {
MATCH_FULL = 0,
MATCH_FRONT_ONLY,
MATCH_MIDDLE_ONLY,
MATCH_END_ONLY,
MATCH_GLOB,
};
struct regex {
char pattern[MAX_FILTER_STR_VAL];
int len;
int field_len;
regex_match_func match;
};
struct filter_pred {
filter_pred_fn_t fn;
u64 val;
struct regex regex;
unsigned short *ops;
struct ftrace_event_field *field;
int offset;
int not;
int op;
unsigned short index;
unsigned short parent;
unsigned short left;
unsigned short right;
};
static inline bool is_string_field(struct ftrace_event_field *field)
{
return field->filter_type == FILTER_DYN_STRING ||
field->filter_type == FILTER_STATIC_STRING ||
field->filter_type == FILTER_PTR_STRING ||
field->filter_type == FILTER_COMM;
}
static inline bool is_function_field(struct ftrace_event_field *field)
{
return field->filter_type == FILTER_TRACE_FN;
}
extern enum regex_type
filter_parse_regex(char *buff, int len, char **search, int *not);
extern void print_event_filter(struct trace_event_file *file,
struct trace_seq *s);
extern int apply_event_filter(struct trace_event_file *file,
char *filter_string);
extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
char *filter_string);
extern void print_subsystem_event_filter(struct event_subsystem *system,
struct trace_seq *s);
extern int filter_assign_type(const char *type);
extern int create_event_filter(struct trace_event_call *call,
char *filter_str, bool set_str,
struct event_filter **filterp);
extern void free_event_filter(struct event_filter *filter);
struct ftrace_event_field *
trace_find_event_field(struct trace_event_call *call, char *name);
extern void trace_event_enable_cmd_record(bool enable);
extern void trace_event_enable_tgid_record(bool enable);
extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
extern int event_trace_del_tracer(struct trace_array *tr);
extern struct trace_event_file *find_event_file(struct trace_array *tr,
const char *system,
const char *event);
static inline void *event_file_data(struct file *filp)
{
return READ_ONCE(file_inode(filp)->i_private);
}
extern struct mutex event_mutex;
extern struct list_head ftrace_events;
extern const struct file_operations event_trigger_fops;
extern const struct file_operations event_hist_fops;
#ifdef CONFIG_HIST_TRIGGERS
extern int register_trigger_hist_cmd(void);
extern int register_trigger_hist_enable_disable_cmds(void);
#else
static inline int register_trigger_hist_cmd(void) { return 0; }
static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
#endif
extern int register_trigger_cmds(void);
extern void clear_event_triggers(struct trace_array *tr);
struct event_trigger_data {
unsigned long count;
int ref;
struct event_trigger_ops *ops;
struct event_command *cmd_ops;
struct event_filter __rcu *filter;
char *filter_str;
void *private_data;
bool paused;
bool paused_tmp;
struct list_head list;
char *name;
struct list_head named_list;
struct event_trigger_data *named_data;
};
/* Avoid typos */
#define ENABLE_EVENT_STR "enable_event"
#define DISABLE_EVENT_STR "disable_event"
#define ENABLE_HIST_STR "enable_hist"
#define DISABLE_HIST_STR "disable_hist"
struct enable_trigger_data {
struct trace_event_file *file;
bool enable;
bool hist;
};
extern int event_enable_trigger_print(struct seq_file *m,
struct event_trigger_ops *ops,
struct event_trigger_data *data);
extern void event_enable_trigger_free(struct event_trigger_ops *ops,
struct event_trigger_data *data);
extern int event_enable_trigger_func(struct event_command *cmd_ops,
struct trace_event_file *file,
char *glob, char *cmd, char *param);
extern int event_enable_register_trigger(char *glob,
struct event_trigger_ops *ops,
struct event_trigger_data *data,
struct trace_event_file *file);
extern void event_enable_unregister_trigger(char *glob,
struct event_trigger_ops *ops,
struct event_trigger_data *test,
struct trace_event_file *file);
extern void trigger_data_free(struct event_trigger_data *data);
extern int event_trigger_init(struct event_trigger_ops *ops,
struct event_trigger_data *data);
extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
int trigger_enable);
extern void update_cond_flag(struct trace_event_file *file);
extern void unregister_trigger(char *glob, struct event_trigger_ops *ops,
struct event_trigger_data *test,
struct trace_event_file *file);
extern int set_trigger_filter(char *filter_str,
struct event_trigger_data *trigger_data,
struct trace_event_file *file);
extern struct event_trigger_data *find_named_trigger(const char *name);
extern bool is_named_trigger(struct event_trigger_data *test);
extern int save_named_trigger(const char *name,
struct event_trigger_data *data);
extern void del_named_trigger(struct event_trigger_data *data);
extern void pause_named_trigger(struct event_trigger_data *data);
extern void unpause_named_trigger(struct event_trigger_data *data);
extern void set_named_trigger_data(struct event_trigger_data *data,
struct event_trigger_data *named_data);
extern struct event_trigger_data *
get_named_trigger_data(struct event_trigger_data *data);
extern int register_event_command(struct event_command *cmd);
extern int unregister_event_command(struct event_command *cmd);
extern int register_trigger_hist_enable_disable_cmds(void);
/**
* struct event_trigger_ops - callbacks for trace event triggers
*
* The methods in this structure provide per-event trigger hooks for
* various trigger operations.
*
* All the methods below, except for @init() and @free(), must be
* implemented.
*
* @func: The trigger 'probe' function called when the triggering
* event occurs. The data passed into this callback is the data
* that was supplied to the event_command @reg() function that
* registered the trigger (see struct event_command) along with
* the trace record, rec.
*
* @init: An optional initialization function called for the trigger
* when the trigger is registered (via the event_command reg()
* function). This can be used to perform per-trigger
* initialization such as incrementing a per-trigger reference
* count, for instance. This is usually implemented by the
* generic utility function @event_trigger_init() (see
* trace_event_triggers.c).
*
* @free: An optional de-initialization function called for the
* trigger when the trigger is unregistered (via the
* event_command @reg() function). This can be used to perform
* per-trigger de-initialization such as decrementing a
* per-trigger reference count and freeing corresponding trigger
* data, for instance. This is usually implemented by the
* generic utility function @event_trigger_free() (see
* trace_event_triggers.c).
*
* @print: The callback function invoked to have the trigger print
* itself. This is usually implemented by a wrapper function
* that calls the generic utility function @event_trigger_print()
* (see trace_event_triggers.c).
*/
struct event_trigger_ops {
void (*func)(struct event_trigger_data *data,
void *rec,
struct ring_buffer_event *rbe);
int (*init)(struct event_trigger_ops *ops,
struct event_trigger_data *data);
void (*free)(struct event_trigger_ops *ops,
struct event_trigger_data *data);
int (*print)(struct seq_file *m,
struct event_trigger_ops *ops,
struct event_trigger_data *data);
};
/**
* struct event_command - callbacks and data members for event commands
*
* Event commands are invoked by users by writing the command name
* into the 'trigger' file associated with a trace event. The
* parameters associated with a specific invocation of an event
* command are used to create an event trigger instance, which is
* added to the list of trigger instances associated with that trace
* event. When the event is hit, the set of triggers associated with
* that event is invoked.
*
* The data members in this structure provide per-event command data
* for various event commands.
*
* All the data members below, except for @post_trigger, must be set
* for each event command.
*
* @name: The unique name that identifies the event command. This is
* the name used when setting triggers via trigger files.
*
* @trigger_type: A unique id that identifies the event command
* 'type'. This value has two purposes, the first to ensure that
* only one trigger of the same type can be set at a given time
* for a particular event e.g. it doesn't make sense to have both
* a traceon and traceoff trigger attached to a single event at
* the same time, so traceon and traceoff have the same type
* though they have different names. The @trigger_type value is
* also used as a bit value for deferring the actual trigger
* action until after the current event is finished. Some
* commands need to do this if they themselves log to the trace
* buffer (see the @post_trigger() member below). @trigger_type
* values are defined by adding new values to the trigger_type
* enum in include/linux/trace_events.h.
*
* @flags: See the enum event_command_flags below.
*
* All the methods below, except for @set_filter() and @unreg_all(),
* must be implemented.
*
* @func: The callback function responsible for parsing and
* registering the trigger written to the 'trigger' file by the
* user. It allocates the trigger instance and registers it with
* the appropriate trace event. It makes use of the other
* event_command callback functions to orchestrate this, and is
* usually implemented by the generic utility function
* @event_trigger_callback() (see trace_event_triggers.c).
*
* @reg: Adds the trigger to the list of triggers associated with the
* event, and enables the event trigger itself, after
* initializing it (via the event_trigger_ops @init() function).
* This is also where commands can use the @trigger_type value to
* make the decision as to whether or not multiple instances of
* the trigger should be allowed. This is usually implemented by
* the generic utility function @register_trigger() (see
* trace_event_triggers.c).
*
* @unreg: Removes the trigger from the list of triggers associated
* with the event, and disables the event trigger itself, after
* initializing it (via the event_trigger_ops @free() function).
* This is usually implemented by the generic utility function
* @unregister_trigger() (see trace_event_triggers.c).
*
* @unreg_all: An optional function called to remove all the triggers
* from the list of triggers associated with the event. Called
* when a trigger file is opened in truncate mode.
*
* @set_filter: An optional function called to parse and set a filter
* for the trigger. If no @set_filter() method is set for the
* event command, filters set by the user for the command will be
* ignored. This is usually implemented by the generic utility
* function @set_trigger_filter() (see trace_event_triggers.c).
*
* @get_trigger_ops: The callback function invoked to retrieve the
* event_trigger_ops implementation associated with the command.
*/
struct event_command {
struct list_head list;
char *name;
enum event_trigger_type trigger_type;
int flags;
int (*func)(struct event_command *cmd_ops,
struct trace_event_file *file,
char *glob, char *cmd, char *params);
int (*reg)(char *glob,
struct event_trigger_ops *ops,
struct event_trigger_data *data,
struct trace_event_file *file);
void (*unreg)(char *glob,
struct event_trigger_ops *ops,
struct event_trigger_data *data,
struct trace_event_file *file);
void (*unreg_all)(struct trace_event_file *file);
int (*set_filter)(char *filter_str,
struct event_trigger_data *data,
struct trace_event_file *file);
struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
};
/**
* enum event_command_flags - flags for struct event_command
*
* @POST_TRIGGER: A flag that says whether or not this command needs
* to have its action delayed until after the current event has
* been closed. Some triggers need to avoid being invoked while
* an event is currently in the process of being logged, since
* the trigger may itself log data into the trace buffer. Thus
* we make sure the current event is committed before invoking
* those triggers. To do that, the trigger invocation is split
* in two - the first part checks the filter using the current
* trace record; if a command has the @post_trigger flag set, it
* sets a bit for itself in the return value, otherwise it
* directly invokes the trigger. Once all commands have been
* either invoked or set their return flag, the current record is
* either committed or discarded. At that point, if any commands
* have deferred their triggers, those commands are finally
* invoked following the close of the current event. In other
* words, if the event_trigger_ops @func() probe implementation
* itself logs to the trace buffer, this flag should be set,
* otherwise it can be left unspecified.
*
* @NEEDS_REC: A flag that says whether or not this command needs
* access to the trace record in order to perform its function,
* regardless of whether or not it has a filter associated with
* it (filters make a trigger require access to the trace record
* but are not always present).
*/
enum event_command_flags {
EVENT_CMD_FL_POST_TRIGGER = 1,
EVENT_CMD_FL_NEEDS_REC = 2,
};
static inline bool event_command_post_trigger(struct event_command *cmd_ops)
{
return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
}
static inline bool event_command_needs_rec(struct event_command *cmd_ops)
{
return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
}
extern int trace_event_enable_disable(struct trace_event_file *file,
int enable, int soft_disable);
extern int tracing_alloc_snapshot(void);
extern const char *__start___trace_bprintk_fmt[];
extern const char *__stop___trace_bprintk_fmt[];
extern const char *__start___tracepoint_str[];
extern const char *__stop___tracepoint_str[];
void trace_printk_control(bool enabled);
void trace_printk_init_buffers(void);
void trace_printk_start_comm(void);
int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
#define MAX_EVENT_NAME_LEN 64
extern int trace_run_command(const char *buf, int (*createfn)(int, char**));
extern ssize_t trace_parse_run_command(struct file *file,
const char __user *buffer, size_t count, loff_t *ppos,
int (*createfn)(int, char**));
/*
* Normal trace_printk() and friends allocates special buffers
* to do the manipulation, as well as saves the print formats
* into sections to display. But the trace infrastructure wants
* to use these without the added overhead at the price of being
* a bit slower (used mainly for warnings, where we don't care
* about performance). The internal_trace_puts() is for such
* a purpose.
*/
#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))
#undef FTRACE_ENTRY
#define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter) \
extern struct trace_event_call \
__aligned(4) event_##call;
#undef FTRACE_ENTRY_DUP
#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter) \
FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
filter)
#undef FTRACE_ENTRY_PACKED
#define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print, filter) \
FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
filter)
#include "trace_entries.h"
#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
int perf_ftrace_event_register(struct trace_event_call *call,
enum trace_reg type, void *data);
#else
#define perf_ftrace_event_register NULL
#endif
#ifdef CONFIG_FTRACE_SYSCALLS
void init_ftrace_syscalls(void);
const char *get_syscall_name(int syscall);
#else
static inline void init_ftrace_syscalls(void) { }
static inline const char *get_syscall_name(int syscall)
{
return NULL;
}
#endif
#ifdef CONFIG_EVENT_TRACING
void trace_event_init(void);
void trace_event_eval_update(struct trace_eval_map **map, int len);
#else
static inline void __init trace_event_init(void) { }
static inline void trace_event_eval_update(struct trace_eval_map **map, int len) { }
#endif
extern struct trace_iterator *tracepoint_print_iter;
#endif /* _LINUX_KERNEL_TRACE_H */