b3806b4316
This patch creates a file called trace_pipe in the tracing debug directory. This file is a consumer of the trace buffers. This means that reads of this file consumes the entries from the trace buffers so that they will not be read a second time, as contrast to the static buffers latency_trace and trace. Reading from the trace_pipe will remove the entries from trace and latency_trace too. The advantage that trace_pipe has is that it can record live traces. It will block when there is nothing in the buffer, and read the entries as they are entered. An EOF happens when tracing is disabled (tracing_enabled = 0). Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
238 lines
6.1 KiB
C
238 lines
6.1 KiB
C
#ifndef _LINUX_KERNEL_TRACE_H
|
|
#define _LINUX_KERNEL_TRACE_H
|
|
|
|
#include <linux/fs.h>
|
|
#include <asm/atomic.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/clocksource.h>
|
|
|
|
/*
|
|
* Function trace entry - function address and parent function addres:
|
|
*/
|
|
struct ftrace_entry {
|
|
unsigned long ip;
|
|
unsigned long parent_ip;
|
|
};
|
|
|
|
/*
|
|
* Context switch trace entry - which task (and prio) we switched from/to:
|
|
*/
|
|
struct ctx_switch_entry {
|
|
unsigned int prev_pid;
|
|
unsigned char prev_prio;
|
|
unsigned char prev_state;
|
|
unsigned int next_pid;
|
|
unsigned char next_prio;
|
|
};
|
|
|
|
/*
|
|
* The trace entry - the most basic unit of tracing. This is what
|
|
* is printed in the end as a single line in the trace output, such as:
|
|
*
|
|
* bash-15816 [01] 235.197585: idle_cpu <- irq_enter
|
|
*/
|
|
struct trace_entry {
|
|
char type;
|
|
char cpu;
|
|
char flags;
|
|
char preempt_count;
|
|
int pid;
|
|
cycle_t t;
|
|
unsigned long idx;
|
|
union {
|
|
struct ftrace_entry fn;
|
|
struct ctx_switch_entry ctx;
|
|
};
|
|
};
|
|
|
|
#define TRACE_ENTRY_SIZE sizeof(struct trace_entry)
|
|
|
|
/*
|
|
* 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 {
|
|
struct list_head trace_pages;
|
|
atomic_t disabled;
|
|
spinlock_t lock;
|
|
cycle_t time_offset;
|
|
|
|
/* these fields get copied into max-trace: */
|
|
unsigned trace_head_idx;
|
|
unsigned trace_tail_idx;
|
|
void *trace_head; /* producer */
|
|
void *trace_tail; /* consumer */
|
|
unsigned long trace_idx;
|
|
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;
|
|
cycle_t preempt_timestamp;
|
|
pid_t pid;
|
|
uid_t uid;
|
|
char comm[TASK_COMM_LEN];
|
|
};
|
|
|
|
struct trace_iterator;
|
|
|
|
/*
|
|
* 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 {
|
|
unsigned long entries;
|
|
long ctrl;
|
|
int cpu;
|
|
cycle_t time_start;
|
|
struct task_struct *waiter;
|
|
struct trace_array_cpu *data[NR_CPUS];
|
|
};
|
|
|
|
/*
|
|
* A specific tracer, represented by methods that operate on a trace array:
|
|
*/
|
|
struct tracer {
|
|
const char *name;
|
|
void (*init)(struct trace_array *tr);
|
|
void (*reset)(struct trace_array *tr);
|
|
void (*open)(struct trace_iterator *iter);
|
|
void (*close)(struct trace_iterator *iter);
|
|
void (*start)(struct trace_iterator *iter);
|
|
void (*stop)(struct trace_iterator *iter);
|
|
void (*ctrl_update)(struct trace_array *tr);
|
|
#ifdef CONFIG_FTRACE_STARTUP_TEST
|
|
int (*selftest)(struct tracer *trace,
|
|
struct trace_array *tr);
|
|
#endif
|
|
struct tracer *next;
|
|
int print_max;
|
|
};
|
|
|
|
struct trace_seq {
|
|
unsigned char buffer[PAGE_SIZE];
|
|
unsigned int len;
|
|
};
|
|
|
|
/*
|
|
* Trace iterator - used by printout routines who present trace
|
|
* results to users and which routines might sleep, etc:
|
|
*/
|
|
struct trace_iterator {
|
|
struct trace_seq seq;
|
|
struct trace_array *tr;
|
|
struct tracer *trace;
|
|
|
|
struct trace_entry *ent;
|
|
int cpu;
|
|
|
|
struct trace_entry *prev_ent;
|
|
int prev_cpu;
|
|
|
|
unsigned long iter_flags;
|
|
loff_t pos;
|
|
unsigned long next_idx[NR_CPUS];
|
|
struct list_head *next_page[NR_CPUS];
|
|
unsigned next_page_idx[NR_CPUS];
|
|
long idx;
|
|
};
|
|
|
|
void notrace tracing_reset(struct trace_array_cpu *data);
|
|
int tracing_open_generic(struct inode *inode, struct file *filp);
|
|
struct dentry *tracing_init_dentry(void);
|
|
void ftrace(struct trace_array *tr,
|
|
struct trace_array_cpu *data,
|
|
unsigned long ip,
|
|
unsigned long parent_ip,
|
|
unsigned long flags);
|
|
void tracing_sched_switch_trace(struct trace_array *tr,
|
|
struct trace_array_cpu *data,
|
|
struct task_struct *prev,
|
|
struct task_struct *next,
|
|
unsigned long flags);
|
|
void tracing_record_cmdline(struct task_struct *tsk);
|
|
|
|
void tracing_start_function_trace(void);
|
|
void tracing_stop_function_trace(void);
|
|
int register_tracer(struct tracer *type);
|
|
void unregister_tracer(struct tracer *type);
|
|
|
|
extern unsigned long nsecs_to_usecs(unsigned long nsecs);
|
|
|
|
extern unsigned long tracing_max_latency;
|
|
extern unsigned long tracing_thresh;
|
|
|
|
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);
|
|
|
|
static inline notrace cycle_t now(int cpu)
|
|
{
|
|
return cpu_clock(cpu);
|
|
}
|
|
|
|
#ifdef CONFIG_SCHED_TRACER
|
|
extern void notrace
|
|
wakeup_sched_switch(struct task_struct *prev, struct task_struct *next);
|
|
#else
|
|
static inline void
|
|
wakeup_sched_switch(struct task_struct *prev, struct task_struct *next)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_CONTEXT_SWITCH_TRACER
|
|
typedef void
|
|
(*tracer_switch_func_t)(void *private,
|
|
struct task_struct *prev,
|
|
struct task_struct *next);
|
|
|
|
struct tracer_switch_ops {
|
|
tracer_switch_func_t func;
|
|
void *private;
|
|
struct tracer_switch_ops *next;
|
|
};
|
|
|
|
extern int register_tracer_switch(struct tracer_switch_ops *ops);
|
|
extern int unregister_tracer_switch(struct tracer_switch_ops *ops);
|
|
|
|
#endif /* CONFIG_CONTEXT_SWITCH_TRACER */
|
|
|
|
#ifdef CONFIG_DYNAMIC_FTRACE
|
|
extern unsigned long ftrace_update_tot_cnt;
|
|
#endif
|
|
|
|
#ifdef CONFIG_FTRACE_STARTUP_TEST
|
|
#ifdef CONFIG_FTRACE
|
|
extern int trace_selftest_startup_function(struct tracer *trace,
|
|
struct trace_array *tr);
|
|
#endif
|
|
#ifdef CONFIG_IRQSOFF_TRACER
|
|
extern int trace_selftest_startup_irqsoff(struct tracer *trace,
|
|
struct trace_array *tr);
|
|
#endif
|
|
#ifdef CONFIG_PREEMPT_TRACER
|
|
extern int trace_selftest_startup_preemptoff(struct tracer *trace,
|
|
struct trace_array *tr);
|
|
#endif
|
|
#if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER)
|
|
extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
|
|
struct trace_array *tr);
|
|
#endif
|
|
#ifdef CONFIG_SCHED_TRACER
|
|
extern int trace_selftest_startup_wakeup(struct tracer *trace,
|
|
struct trace_array *tr);
|
|
#endif
|
|
#ifdef CONFIG_CONTEXT_SWITCH_TRACER
|
|
extern int trace_selftest_startup_sched_switch(struct tracer *trace,
|
|
struct trace_array *tr);
|
|
#endif
|
|
#endif /* CONFIG_FTRACE_STARTUP_TEST */
|
|
|
|
extern void *head_page(struct trace_array_cpu *data);
|
|
|
|
#endif /* _LINUX_KERNEL_TRACE_H */
|