668 lines
18 KiB
C
668 lines
18 KiB
C
#ifndef _LINUX_KERNEL_TRACE_H
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#define _LINUX_KERNEL_TRACE_H
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#include <linux/fs.h>
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#include <asm/atomic.h>
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#include <linux/sched.h>
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#include <linux/clocksource.h>
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#include <linux/ring_buffer.h>
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#include <linux/mmiotrace.h>
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#include <linux/ftrace.h>
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#include <trace/boot.h>
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enum trace_type {
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__TRACE_FIRST_TYPE = 0,
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TRACE_FN,
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TRACE_CTX,
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TRACE_WAKE,
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TRACE_CONT,
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TRACE_STACK,
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TRACE_PRINT,
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TRACE_SPECIAL,
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TRACE_MMIO_RW,
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TRACE_MMIO_MAP,
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TRACE_BRANCH,
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TRACE_BOOT_CALL,
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TRACE_BOOT_RET,
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TRACE_GRAPH_RET,
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TRACE_GRAPH_ENT,
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TRACE_USER_STACK,
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TRACE_HW_BRANCHES,
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TRACE_POWER,
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__TRACE_LAST_TYPE
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};
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/*
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* The trace entry - the most basic unit of tracing. This is what
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* is printed in the end as a single line in the trace output, such as:
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*
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* bash-15816 [01] 235.197585: idle_cpu <- irq_enter
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*/
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struct trace_entry {
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unsigned char type;
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unsigned char cpu;
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unsigned char flags;
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unsigned char preempt_count;
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int pid;
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int tgid;
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};
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/*
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* Function trace entry - function address and parent function addres:
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*/
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struct ftrace_entry {
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struct trace_entry ent;
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unsigned long ip;
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unsigned long parent_ip;
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};
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/* Function call entry */
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struct ftrace_graph_ent_entry {
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struct trace_entry ent;
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struct ftrace_graph_ent graph_ent;
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};
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/* Function return entry */
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struct ftrace_graph_ret_entry {
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struct trace_entry ent;
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struct ftrace_graph_ret ret;
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};
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extern struct tracer boot_tracer;
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/*
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* Context switch trace entry - which task (and prio) we switched from/to:
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*/
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struct ctx_switch_entry {
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struct trace_entry ent;
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unsigned int prev_pid;
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unsigned char prev_prio;
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unsigned char prev_state;
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unsigned int next_pid;
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unsigned char next_prio;
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unsigned char next_state;
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unsigned int next_cpu;
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};
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/*
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* Special (free-form) trace entry:
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*/
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struct special_entry {
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struct trace_entry ent;
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unsigned long arg1;
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unsigned long arg2;
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unsigned long arg3;
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};
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/*
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* Stack-trace entry:
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*/
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#define FTRACE_STACK_ENTRIES 8
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struct stack_entry {
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struct trace_entry ent;
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unsigned long caller[FTRACE_STACK_ENTRIES];
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};
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struct userstack_entry {
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struct trace_entry ent;
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unsigned long caller[FTRACE_STACK_ENTRIES];
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};
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/*
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* ftrace_printk entry:
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*/
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struct print_entry {
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struct trace_entry ent;
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unsigned long ip;
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int depth;
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char buf[];
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};
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#define TRACE_OLD_SIZE 88
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struct trace_field_cont {
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unsigned char type;
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/* Temporary till we get rid of this completely */
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char buf[TRACE_OLD_SIZE - 1];
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};
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struct trace_mmiotrace_rw {
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struct trace_entry ent;
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struct mmiotrace_rw rw;
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};
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struct trace_mmiotrace_map {
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struct trace_entry ent;
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struct mmiotrace_map map;
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};
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struct trace_boot_call {
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struct trace_entry ent;
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struct boot_trace_call boot_call;
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};
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struct trace_boot_ret {
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struct trace_entry ent;
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struct boot_trace_ret boot_ret;
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};
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#define TRACE_FUNC_SIZE 30
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#define TRACE_FILE_SIZE 20
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struct trace_branch {
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struct trace_entry ent;
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unsigned line;
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char func[TRACE_FUNC_SIZE+1];
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char file[TRACE_FILE_SIZE+1];
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char correct;
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};
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struct hw_branch_entry {
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struct trace_entry ent;
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u64 from;
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u64 to;
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};
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struct trace_power {
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struct trace_entry ent;
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struct power_trace state_data;
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};
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/*
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* trace_flag_type is an enumeration that holds different
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* states when a trace occurs. These are:
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* IRQS_OFF - interrupts were disabled
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* IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
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* NEED_RESCED - reschedule is requested
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* HARDIRQ - inside an interrupt handler
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* SOFTIRQ - inside a softirq handler
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* CONT - multiple entries hold the trace item
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*/
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enum trace_flag_type {
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TRACE_FLAG_IRQS_OFF = 0x01,
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TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
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TRACE_FLAG_NEED_RESCHED = 0x04,
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TRACE_FLAG_HARDIRQ = 0x08,
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TRACE_FLAG_SOFTIRQ = 0x10,
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TRACE_FLAG_CONT = 0x20,
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};
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#define TRACE_BUF_SIZE 1024
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/*
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* The CPU trace array - it consists of thousands of trace entries
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* plus some other descriptor data: (for example which task started
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* the trace, etc.)
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*/
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struct trace_array_cpu {
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atomic_t disabled;
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/* these fields get copied into max-trace: */
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unsigned long trace_idx;
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unsigned long overrun;
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unsigned long saved_latency;
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unsigned long critical_start;
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unsigned long critical_end;
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unsigned long critical_sequence;
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unsigned long nice;
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unsigned long policy;
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unsigned long rt_priority;
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cycle_t preempt_timestamp;
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pid_t pid;
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uid_t uid;
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char comm[TASK_COMM_LEN];
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};
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struct trace_iterator;
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/*
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* The trace array - an array of per-CPU trace arrays. This is the
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* highest level data structure that individual tracers deal with.
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* They have on/off state as well:
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*/
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struct trace_array {
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struct ring_buffer *buffer;
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unsigned long entries;
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int cpu;
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cycle_t time_start;
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struct task_struct *waiter;
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struct trace_array_cpu *data[NR_CPUS];
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};
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#define FTRACE_CMP_TYPE(var, type) \
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__builtin_types_compatible_p(typeof(var), type *)
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#undef IF_ASSIGN
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#define IF_ASSIGN(var, entry, etype, id) \
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if (FTRACE_CMP_TYPE(var, etype)) { \
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var = (typeof(var))(entry); \
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WARN_ON(id && (entry)->type != id); \
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break; \
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}
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/* Will cause compile errors if type is not found. */
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extern void __ftrace_bad_type(void);
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/*
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* The trace_assign_type is a verifier that the entry type is
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* the same as the type being assigned. To add new types simply
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* add a line with the following format:
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*
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* IF_ASSIGN(var, ent, type, id);
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*
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* Where "type" is the trace type that includes the trace_entry
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* as the "ent" item. And "id" is the trace identifier that is
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* used in the trace_type enum.
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*
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* If the type can have more than one id, then use zero.
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*/
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#define trace_assign_type(var, ent) \
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do { \
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IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
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IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
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IF_ASSIGN(var, ent, struct trace_field_cont, TRACE_CONT); \
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IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
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IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
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IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
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IF_ASSIGN(var, ent, struct special_entry, 0); \
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IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
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TRACE_MMIO_RW); \
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IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
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TRACE_MMIO_MAP); \
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IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
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IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
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IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
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IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
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TRACE_GRAPH_ENT); \
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IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
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TRACE_GRAPH_RET); \
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IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
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IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
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__ftrace_bad_type(); \
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} while (0)
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/* Return values for print_line callback */
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enum print_line_t {
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TRACE_TYPE_PARTIAL_LINE = 0, /* Retry after flushing the seq */
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TRACE_TYPE_HANDLED = 1,
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TRACE_TYPE_UNHANDLED = 2 /* Relay to other output functions */
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};
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/*
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* An option specific to a tracer. This is a boolean value.
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* The bit is the bit index that sets its value on the
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* flags value in struct tracer_flags.
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*/
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struct tracer_opt {
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const char *name; /* Will appear on the trace_options file */
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u32 bit; /* Mask assigned in val field in tracer_flags */
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};
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/*
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* The set of specific options for a tracer. Your tracer
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* have to set the initial value of the flags val.
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*/
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struct tracer_flags {
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u32 val;
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struct tracer_opt *opts;
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};
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/* Makes more easy to define a tracer opt */
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#define TRACER_OPT(s, b) .name = #s, .bit = b
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/*
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* A specific tracer, represented by methods that operate on a trace array:
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*/
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struct tracer {
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const char *name;
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/* Your tracer should raise a warning if init fails */
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int (*init)(struct trace_array *tr);
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void (*reset)(struct trace_array *tr);
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void (*start)(struct trace_array *tr);
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void (*stop)(struct trace_array *tr);
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void (*open)(struct trace_iterator *iter);
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void (*pipe_open)(struct trace_iterator *iter);
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void (*close)(struct trace_iterator *iter);
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ssize_t (*read)(struct trace_iterator *iter,
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struct file *filp, char __user *ubuf,
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size_t cnt, loff_t *ppos);
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#ifdef CONFIG_FTRACE_STARTUP_TEST
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int (*selftest)(struct tracer *trace,
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struct trace_array *tr);
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#endif
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void (*print_header)(struct seq_file *m);
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enum print_line_t (*print_line)(struct trace_iterator *iter);
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/* If you handled the flag setting, return 0 */
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int (*set_flag)(u32 old_flags, u32 bit, int set);
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struct tracer *next;
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int print_max;
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struct tracer_flags *flags;
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};
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struct trace_seq {
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unsigned char buffer[PAGE_SIZE];
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unsigned int len;
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unsigned int readpos;
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};
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/*
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* Trace iterator - used by printout routines who present trace
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* results to users and which routines might sleep, etc:
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*/
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struct trace_iterator {
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struct trace_array *tr;
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struct tracer *trace;
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void *private;
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struct ring_buffer_iter *buffer_iter[NR_CPUS];
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/* The below is zeroed out in pipe_read */
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struct trace_seq seq;
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struct trace_entry *ent;
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int cpu;
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u64 ts;
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unsigned long iter_flags;
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loff_t pos;
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long idx;
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cpumask_t started;
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};
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int tracing_is_enabled(void);
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void trace_wake_up(void);
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void tracing_reset(struct trace_array *tr, int cpu);
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void tracing_reset_online_cpus(struct trace_array *tr);
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int tracing_open_generic(struct inode *inode, struct file *filp);
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struct dentry *tracing_init_dentry(void);
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void init_tracer_sysprof_debugfs(struct dentry *d_tracer);
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struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
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struct trace_array_cpu *data);
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void tracing_generic_entry_update(struct trace_entry *entry,
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unsigned long flags,
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int pc);
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void ftrace(struct trace_array *tr,
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struct trace_array_cpu *data,
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unsigned long ip,
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unsigned long parent_ip,
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unsigned long flags, int pc);
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void tracing_sched_switch_trace(struct trace_array *tr,
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struct trace_array_cpu *data,
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struct task_struct *prev,
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struct task_struct *next,
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unsigned long flags, int pc);
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void tracing_record_cmdline(struct task_struct *tsk);
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void tracing_sched_wakeup_trace(struct trace_array *tr,
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struct trace_array_cpu *data,
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struct task_struct *wakee,
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struct task_struct *cur,
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unsigned long flags, int pc);
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void trace_special(struct trace_array *tr,
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struct trace_array_cpu *data,
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unsigned long arg1,
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unsigned long arg2,
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unsigned long arg3, int pc);
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void trace_function(struct trace_array *tr,
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struct trace_array_cpu *data,
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unsigned long ip,
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unsigned long parent_ip,
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unsigned long flags, int pc);
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void trace_graph_return(struct ftrace_graph_ret *trace);
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int trace_graph_entry(struct ftrace_graph_ent *trace);
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void trace_hw_branch(struct trace_array *tr, u64 from, u64 to);
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void tracing_start_cmdline_record(void);
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void tracing_stop_cmdline_record(void);
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void tracing_sched_switch_assign_trace(struct trace_array *tr);
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void tracing_stop_sched_switch_record(void);
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void tracing_start_sched_switch_record(void);
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int register_tracer(struct tracer *type);
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void unregister_tracer(struct tracer *type);
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extern unsigned long nsecs_to_usecs(unsigned long nsecs);
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extern unsigned long tracing_max_latency;
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extern unsigned long tracing_thresh;
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void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
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void update_max_tr_single(struct trace_array *tr,
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struct task_struct *tsk, int cpu);
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extern cycle_t ftrace_now(int cpu);
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#ifdef CONFIG_FUNCTION_TRACER
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void tracing_start_function_trace(void);
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void tracing_stop_function_trace(void);
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#else
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# define tracing_start_function_trace() do { } while (0)
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# define tracing_stop_function_trace() do { } while (0)
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#endif
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#ifdef CONFIG_CONTEXT_SWITCH_TRACER
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typedef void
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(*tracer_switch_func_t)(void *private,
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void *__rq,
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struct task_struct *prev,
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struct task_struct *next);
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struct tracer_switch_ops {
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tracer_switch_func_t func;
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void *private;
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struct tracer_switch_ops *next;
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};
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char *trace_find_cmdline(int pid);
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#endif /* CONFIG_CONTEXT_SWITCH_TRACER */
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#ifdef CONFIG_DYNAMIC_FTRACE
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extern unsigned long ftrace_update_tot_cnt;
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#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
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extern int DYN_FTRACE_TEST_NAME(void);
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#endif
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#ifdef CONFIG_FTRACE_STARTUP_TEST
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extern int trace_selftest_startup_function(struct tracer *trace,
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struct trace_array *tr);
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extern int trace_selftest_startup_irqsoff(struct tracer *trace,
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struct trace_array *tr);
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extern int trace_selftest_startup_preemptoff(struct tracer *trace,
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struct trace_array *tr);
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extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
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struct trace_array *tr);
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extern int trace_selftest_startup_wakeup(struct tracer *trace,
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struct trace_array *tr);
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extern int trace_selftest_startup_nop(struct tracer *trace,
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struct trace_array *tr);
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extern int trace_selftest_startup_sched_switch(struct tracer *trace,
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struct trace_array *tr);
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extern int trace_selftest_startup_sysprof(struct tracer *trace,
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struct trace_array *tr);
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extern int trace_selftest_startup_branch(struct tracer *trace,
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struct trace_array *tr);
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#endif /* CONFIG_FTRACE_STARTUP_TEST */
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extern void *head_page(struct trace_array_cpu *data);
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extern int trace_seq_printf(struct trace_seq *s, const char *fmt, ...);
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extern void trace_seq_print_cont(struct trace_seq *s,
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struct trace_iterator *iter);
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extern int
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seq_print_ip_sym(struct trace_seq *s, unsigned long ip,
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unsigned long sym_flags);
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extern ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
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size_t cnt);
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extern long ns2usecs(cycle_t nsec);
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extern int
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trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args);
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extern unsigned long trace_flags;
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/* Standard output formatting function used for function return traces */
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#ifdef CONFIG_FUNCTION_GRAPH_TRACER
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extern enum print_line_t print_graph_function(struct trace_iterator *iter);
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#ifdef CONFIG_DYNAMIC_FTRACE
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/* TODO: make this variable */
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#define FTRACE_GRAPH_MAX_FUNCS 32
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extern int ftrace_graph_count;
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extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
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static inline int ftrace_graph_addr(unsigned long addr)
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{
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int i;
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if (!ftrace_graph_count || test_tsk_trace_graph(current))
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return 1;
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for (i = 0; i < ftrace_graph_count; i++) {
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if (addr == ftrace_graph_funcs[i])
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return 1;
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}
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return 0;
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}
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#else
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static inline int ftrace_trace_addr(unsigned long addr)
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{
|
|
return 1;
|
|
}
|
|
static inline int ftrace_graph_addr(unsigned long addr)
|
|
{
|
|
return 1;
|
|
}
|
|
#endif /* CONFIG_DYNAMIC_FTRACE */
|
|
|
|
#else /* CONFIG_FUNCTION_GRAPH_TRACER */
|
|
static inline enum print_line_t
|
|
print_graph_function(struct trace_iterator *iter)
|
|
{
|
|
return TRACE_TYPE_UNHANDLED;
|
|
}
|
|
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
|
|
|
|
extern struct pid *ftrace_pid_trace;
|
|
|
|
static inline int ftrace_trace_task(struct task_struct *task)
|
|
{
|
|
if (!ftrace_pid_trace)
|
|
return 1;
|
|
|
|
return test_tsk_trace_trace(task);
|
|
}
|
|
|
|
/*
|
|
* 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_SCHED_TREE = 0x200,
|
|
TRACE_ITER_PRINTK = 0x400,
|
|
TRACE_ITER_PREEMPTONLY = 0x800,
|
|
TRACE_ITER_BRANCH = 0x1000,
|
|
TRACE_ITER_ANNOTATE = 0x2000,
|
|
TRACE_ITER_USERSTACKTRACE = 0x4000,
|
|
TRACE_ITER_SYM_USEROBJ = 0x8000,
|
|
TRACE_ITER_PRINTK_MSGONLY = 0x10000
|
|
};
|
|
|
|
/*
|
|
* 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;
|
|
|
|
/**
|
|
* ftrace_preempt_disable - disable preemption scheduler safe
|
|
*
|
|
* When tracing can happen inside the scheduler, there exists
|
|
* cases that the tracing might happen before the need_resched
|
|
* flag is checked. If this happens and the tracer calls
|
|
* preempt_enable (after a disable), a schedule might take place
|
|
* causing an infinite recursion.
|
|
*
|
|
* To prevent this, we read the need_recshed flag before
|
|
* disabling preemption. When we want to enable preemption we
|
|
* check the flag, if it is set, then we call preempt_enable_no_resched.
|
|
* Otherwise, we call preempt_enable.
|
|
*
|
|
* The rational for doing the above is that if need resched is set
|
|
* and we have yet to reschedule, we are either in an atomic location
|
|
* (where we do not need to check for scheduling) or we are inside
|
|
* the scheduler and do not want to resched.
|
|
*/
|
|
static inline int ftrace_preempt_disable(void)
|
|
{
|
|
int resched;
|
|
|
|
resched = need_resched();
|
|
preempt_disable_notrace();
|
|
|
|
return resched;
|
|
}
|
|
|
|
/**
|
|
* ftrace_preempt_enable - enable preemption scheduler safe
|
|
* @resched: the return value from ftrace_preempt_disable
|
|
*
|
|
* This is a scheduler safe way to enable preemption and not miss
|
|
* any preemption checks. The disabled saved the state of preemption.
|
|
* If resched is set, then we were either inside an atomic or
|
|
* are inside the scheduler (we would have already scheduled
|
|
* otherwise). In this case, we do not want to call normal
|
|
* preempt_enable, but preempt_enable_no_resched instead.
|
|
*/
|
|
static inline void ftrace_preempt_enable(int resched)
|
|
{
|
|
if (resched)
|
|
preempt_enable_no_resched_notrace();
|
|
else
|
|
preempt_enable_notrace();
|
|
}
|
|
|
|
#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 */
|
|
|
|
#endif /* _LINUX_KERNEL_TRACE_H */
|