linux/kernel/trace/trace.h
Steven Rostedt (Red Hat) 50512ab576 tracing: Convert tracer->enabled to counter
As tracers will soon be used by instances, the tracer enabled field
needs to be converted to a counter instead of a boolean.
This counter is protected by the trace_types_lock mutex.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-02-20 12:13:17 -05:00

1269 lines
38 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/ftrace_event.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 TP_ARGS
#define TP_ARGS(args...) args
#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)
#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,
};
#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];
};
struct tracer;
struct trace_buffer {
struct trace_array *tr;
struct ring_buffer *buffer;
struct trace_array_cpu __percpu *data;
cycle_t time_start;
int cpu;
};
/*
* 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
int buffer_disabled;
#ifdef CONFIG_FTRACE_SYSCALLS
int sys_refcount_enter;
int sys_refcount_exit;
struct ftrace_event_file __rcu *enter_syscall_files[NR_syscalls];
struct ftrace_event_file __rcu *exit_syscall_files[NR_syscalls];
#endif
int stop_count;
int clock_id;
struct tracer *current_trace;
unsigned int flags;
raw_spinlock_t start_lock;
struct dentry *dir;
struct dentry *options;
struct dentry *percpu_dir;
struct dentry *event_dir;
struct list_head systems;
struct list_head events;
cpumask_var_t tracing_cpumask; /* only trace on set CPUs */
int ref;
};
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;
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;
};
/* Makes more easy to define a tracer opt */
#define TRACER_OPT(s, b) .name = #s, .bit = b
/**
* struct tracer - a specific tracer and its callbacks to interact with debugfs
* @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_enabled)
* @stop: called when tracing is paused (echo 0 > tracing_enabled)
* @open: called when the trace file is opened
* @pipe_open: called when the trace_pipe file is opened
* @wait_pipe: override how the user waits for traces on trace_pipe
* @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);
void (*open)(struct trace_iterator *iter);
void (*pipe_open)(struct trace_iterator *iter);
void (*wait_pipe)(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;
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,
/* GLOBAL_BITs must be greater than FTRACE_BITs */
TRACE_GLOBAL_BIT,
TRACE_GLOBAL_NMI_BIT,
TRACE_GLOBAL_IRQ_BIT,
TRACE_GLOBAL_SIRQ_BIT,
/* INTERNAL_BITs must be greater than GLOBAL_BITs */
TRACE_INTERNAL_BIT,
TRACE_INTERNAL_NMI_BIT,
TRACE_INTERNAL_IRQ_BIT,
TRACE_INTERNAL_SIRQ_BIT,
TRACE_CONTROL_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_GLOBAL_START TRACE_GLOBAL_BIT
#define TRACE_GLOBAL_MAX ((1 << (TRACE_GLOBAL_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_tr(struct trace_array *tr);
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 poll_wait_pipe(struct trace_iterator *iter);
void tracing_sched_switch_trace(struct trace_array *tr,
struct task_struct *prev,
struct task_struct *next,
unsigned long flags, int pc);
void tracing_sched_wakeup_trace(struct trace_array *tr,
struct task_struct *wakee,
struct task_struct *cur,
unsigned long flags, int pc);
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_sched_switch_assign_trace(struct trace_array *tr);
void tracing_stop_sched_switch_record(void);
void tracing_start_sched_switch_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;
#ifdef CONFIG_TRACER_MAX_TRACE
extern unsigned long tracing_max_latency;
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_stack(struct ring_buffer *buffer, unsigned long flags,
int skip, int pc);
void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags,
int skip, int pc, struct pt_regs *regs);
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_stack(struct ring_buffer *buffer,
unsigned long flags, int skip, int pc)
{
}
static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer,
unsigned long flags, int skip,
int pc, struct pt_regs *regs)
{
}
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[]);
#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;
DECLARE_PER_CPU(int, ftrace_cpu_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 unsigned long trace_flags;
/* 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_FILL_SHIFT 28
#define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
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 enum print_line_t
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 task_struct *task)
{
if (list_empty(&ftrace_pids))
return 1;
return test_tsk_trace_trace(task);
}
extern int ftrace_is_dead(void);
#else
static inline int ftrace_trace_task(struct task_struct *task)
{
return 1;
}
static inline int ftrace_is_dead(void) { return 0; }
#endif
int ftrace_event_is_function(struct ftrace_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);
/*
* 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.
*/
enum trace_iterator_flags {
TRACE_ITER_PRINT_PARENT = 0x01,
TRACE_ITER_SYM_OFFSET = 0x02,
TRACE_ITER_SYM_ADDR = 0x04,
TRACE_ITER_VERBOSE = 0x08,
TRACE_ITER_RAW = 0x10,
TRACE_ITER_HEX = 0x20,
TRACE_ITER_BIN = 0x40,
TRACE_ITER_BLOCK = 0x80,
TRACE_ITER_STACKTRACE = 0x100,
TRACE_ITER_PRINTK = 0x200,
TRACE_ITER_PREEMPTONLY = 0x400,
TRACE_ITER_BRANCH = 0x800,
TRACE_ITER_ANNOTATE = 0x1000,
TRACE_ITER_USERSTACKTRACE = 0x2000,
TRACE_ITER_SYM_USEROBJ = 0x4000,
TRACE_ITER_PRINTK_MSGONLY = 0x8000,
TRACE_ITER_CONTEXT_INFO = 0x10000, /* Print pid/cpu/time */
TRACE_ITER_LATENCY_FMT = 0x20000,
TRACE_ITER_SLEEP_TIME = 0x40000,
TRACE_ITER_GRAPH_TIME = 0x80000,
TRACE_ITER_RECORD_CMD = 0x100000,
TRACE_ITER_OVERWRITE = 0x200000,
TRACE_ITER_STOP_ON_FREE = 0x400000,
TRACE_ITER_IRQ_INFO = 0x800000,
TRACE_ITER_MARKERS = 0x1000000,
TRACE_ITER_FUNCTION = 0x2000000,
};
/*
* 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 (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 ftrace_subsystem_dir {
struct list_head list;
struct event_subsystem *subsystem;
struct trace_array *tr;
struct dentry *entry;
int ref_count;
int nr_events;
};
#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;
};
extern enum regex_type
filter_parse_regex(char *buff, int len, char **search, int *not);
extern void print_event_filter(struct ftrace_event_file *file,
struct trace_seq *s);
extern int apply_event_filter(struct ftrace_event_file *file,
char *filter_string);
extern int apply_subsystem_event_filter(struct ftrace_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 ftrace_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 ftrace_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 ftrace_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 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;
struct list_head list;
};
/**
* 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).
*
* @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);
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/ftrace_event.h.
*
* @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.
*
* All the methods below, except for @set_filter(), 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).
*
* @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;
bool post_trigger;
int (*func)(struct event_command *cmd_ops,
struct ftrace_event_file *file,
char *glob, char *cmd, char *params);
int (*reg)(char *glob,
struct event_trigger_ops *ops,
struct event_trigger_data *data,
struct ftrace_event_file *file);
void (*unreg)(char *glob,
struct event_trigger_ops *ops,
struct event_trigger_data *data,
struct ftrace_event_file *file);
int (*set_filter)(char *filter_str,
struct event_trigger_data *data,
struct ftrace_event_file *file);
struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
};
extern int trace_event_enable_disable(struct ftrace_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_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 ftrace_event_call \
__attribute__((__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)
#include "trace_entries.h"
#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
int perf_ftrace_event_register(struct ftrace_event_call *call,
enum trace_reg type, void *data);
#else
#define perf_ftrace_event_register NULL
#endif
#endif /* _LINUX_KERNEL_TRACE_H */