linux/kernel/trace/trace.h
Namhyung Kim a4a551b8f1 ftrace: Reduce size of function graph entries
Currently ftrace_graph_ent{,_entry} and ftrace_graph_ret{,_entry} struct
can have padding bytes at the end due to alignment in 64-bit data type.
As these data are recorded so frequently, those paddings waste
non-negligible space.  As the ring buffer maintains alignment properly
for each architecture, just to remove the extra padding using 'packed'
attribute.

  ftrace_graph_ent_entry:  24 -> 20
  ftrace_graph_ret_entry:  48 -> 44

Also I moved the 'overrun' field in struct ftrace_graph_ret to minimize
the padding in the middle.

Tested on x86_64 only.

Link: http://lkml.kernel.org/r/1467197808-13578-1-git-send-email-namhyung@kernel.org

Cc: Ingo Molnar <mingo@kernel.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2016-07-05 17:28:30 -04:00

1670 lines
52 KiB
C

#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>
#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_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;
cycle_t 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;
cycle_t 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;
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;
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;
/* function tracing enabled */
int function_enabled;
#endif
};
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);
/*
* 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 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
};
/* 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);
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 __buffer_unlock_commit(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);
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 cycle_t ftrace_now(int cpu);
extern void trace_find_cmdline(int pid, char comm[]);
extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
#ifdef CONFIG_DYNAMIC_FTRACE
extern unsigned long ftrace_update_tot_cnt;
#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_sched_switch(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(cycle_t 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);
/* 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
/* TODO: make this variable */
#define FTRACE_GRAPH_MAX_FUNCS 32
extern int ftrace_graph_count;
extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
extern int ftrace_graph_notrace_count;
extern unsigned long ftrace_graph_notrace_funcs[FTRACE_GRAPH_MAX_FUNCS];
static inline int ftrace_graph_addr(unsigned long addr)
{
int i;
if (!ftrace_graph_count)
return 1;
for (i = 0; i < ftrace_graph_count; i++) {
if (addr == ftrace_graph_funcs[i]) {
/*
* 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);
return 1;
}
}
return 0;
}
static inline int ftrace_graph_notrace_addr(unsigned long addr)
{
int i;
if (!ftrace_graph_notrace_count)
return 0;
for (i = 0; i < ftrace_graph_notrace_count; i++) {
if (addr == ftrace_graph_notrace_funcs[i])
return 1;
}
return 0;
}
#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 */
#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
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);
#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) { }
/* 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)
void ftrace_create_filter_files(struct ftrace_ops *ops,
struct dentry *parent);
void ftrace_destroy_filter_files(struct ftrace_ops *ops);
#else
/*
* 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"),
# define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION
#else
# define FUNCTION_FLAGS
# define FUNCTION_DEFAULT_FLAGS 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(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 *preds;
struct filter_pred *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);
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_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);
}
#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,
};
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;
}
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 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 ACCESS_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 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);
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);
/*
* 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_enum_update(struct trace_enum_map **map, int len);
#else
static inline void __init trace_event_init(void) { }
static inline void trace_event_enum_update(struct trace_enum_map **map, int len) { }
#endif
extern struct trace_iterator *tracepoint_print_iter;
#endif /* _LINUX_KERNEL_TRACE_H */