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-rw-r--r--kernel/trace/Makefile2
-rw-r--r--kernel/trace/trace.c741
-rw-r--r--kernel/trace/trace.h36
-rw-r--r--kernel/trace/trace_boot.c1
-rw-r--r--kernel/trace/trace_branch.c295
-rw-r--r--kernel/trace/trace_functions_graph.c4
-rw-r--r--kernel/trace/trace_hw_branches.c1
-rw-r--r--kernel/trace/trace_mmiotrace.c4
-rw-r--r--kernel/trace/trace_output.c832
-rw-r--r--kernel/trace/trace_output.h59
-rw-r--r--kernel/trace/trace_power.c1
-rw-r--r--kernel/trace/trace_selftest.c1
-rw-r--r--kernel/trace/trace_stat.c251
13 files changed, 1392 insertions, 836 deletions
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index 513dc86b5df..05c9182061d 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -19,6 +19,8 @@ obj-$(CONFIG_FUNCTION_TRACER) += libftrace.o
obj-$(CONFIG_RING_BUFFER) += ring_buffer.o
obj-$(CONFIG_TRACING) += trace.o
+obj-$(CONFIG_TRACING) += trace_output.o
+obj-$(CONFIG_TRACING) += trace_stat.o
obj-$(CONFIG_CONTEXT_SWITCH_TRACER) += trace_sched_switch.o
obj-$(CONFIG_SYSPROF_TRACER) += trace_sysprof.o
obj-$(CONFIG_FUNCTION_TRACER) += trace_functions.o
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index c580233add9..0418fc338b5 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -37,6 +37,7 @@
#include <linux/irqflags.h>
#include "trace.h"
+#include "trace_output.h"
#define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE)
@@ -329,132 +330,6 @@ __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
tracing_record_cmdline(current);
}
-/**
- * trace_seq_printf - sequence printing of trace information
- * @s: trace sequence descriptor
- * @fmt: printf format string
- *
- * The tracer may use either sequence operations or its own
- * copy to user routines. To simplify formating of a trace
- * trace_seq_printf is used to store strings into a special
- * buffer (@s). Then the output may be either used by
- * the sequencer or pulled into another buffer.
- */
-int
-trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
-{
- int len = (PAGE_SIZE - 1) - s->len;
- va_list ap;
- int ret;
-
- if (!len)
- return 0;
-
- va_start(ap, fmt);
- ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
- va_end(ap);
-
- /* If we can't write it all, don't bother writing anything */
- if (ret >= len)
- return 0;
-
- s->len += ret;
-
- return len;
-}
-
-/**
- * trace_seq_puts - trace sequence printing of simple string
- * @s: trace sequence descriptor
- * @str: simple string to record
- *
- * The tracer may use either the sequence operations or its own
- * copy to user routines. This function records a simple string
- * into a special buffer (@s) for later retrieval by a sequencer
- * or other mechanism.
- */
-static int
-trace_seq_puts(struct trace_seq *s, const char *str)
-{
- int len = strlen(str);
-
- if (len > ((PAGE_SIZE - 1) - s->len))
- return 0;
-
- memcpy(s->buffer + s->len, str, len);
- s->len += len;
-
- return len;
-}
-
-static int
-trace_seq_putc(struct trace_seq *s, unsigned char c)
-{
- if (s->len >= (PAGE_SIZE - 1))
- return 0;
-
- s->buffer[s->len++] = c;
-
- return 1;
-}
-
-static int
-trace_seq_putmem(struct trace_seq *s, void *mem, size_t len)
-{
- if (len > ((PAGE_SIZE - 1) - s->len))
- return 0;
-
- memcpy(s->buffer + s->len, mem, len);
- s->len += len;
-
- return len;
-}
-
-#define MAX_MEMHEX_BYTES 8
-#define HEX_CHARS (MAX_MEMHEX_BYTES*2 + 1)
-
-static int
-trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len)
-{
- unsigned char hex[HEX_CHARS];
- unsigned char *data = mem;
- int i, j;
-
-#ifdef __BIG_ENDIAN
- for (i = 0, j = 0; i < len; i++) {
-#else
- for (i = len-1, j = 0; i >= 0; i--) {
-#endif
- hex[j++] = hex_asc_hi(data[i]);
- hex[j++] = hex_asc_lo(data[i]);
- }
- hex[j++] = ' ';
-
- return trace_seq_putmem(s, hex, j);
-}
-
-static int
-trace_seq_path(struct trace_seq *s, struct path *path)
-{
- unsigned char *p;
-
- if (s->len >= (PAGE_SIZE - 1))
- return 0;
- p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
- if (!IS_ERR(p)) {
- p = mangle_path(s->buffer + s->len, p, "\n");
- if (p) {
- s->len = p - s->buffer;
- return 1;
- }
- } else {
- s->buffer[s->len++] = '?';
- return 1;
- }
-
- return 0;
-}
-
static void
trace_seq_reset(struct trace_seq *s)
{
@@ -1472,154 +1347,6 @@ static void s_stop(struct seq_file *m, void *p)
mutex_unlock(&trace_types_lock);
}
-#ifdef CONFIG_KRETPROBES
-static inline const char *kretprobed(const char *name)
-{
- static const char tramp_name[] = "kretprobe_trampoline";
- int size = sizeof(tramp_name);
-
- if (strncmp(tramp_name, name, size) == 0)
- return "[unknown/kretprobe'd]";
- return name;
-}
-#else
-static inline const char *kretprobed(const char *name)
-{
- return name;
-}
-#endif /* CONFIG_KRETPROBES */
-
-static int
-seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
-{
-#ifdef CONFIG_KALLSYMS
- char str[KSYM_SYMBOL_LEN];
- const char *name;
-
- kallsyms_lookup(address, NULL, NULL, NULL, str);
-
- name = kretprobed(str);
-
- return trace_seq_printf(s, fmt, name);
-#endif
- return 1;
-}
-
-static int
-seq_print_sym_offset(struct trace_seq *s, const char *fmt,
- unsigned long address)
-{
-#ifdef CONFIG_KALLSYMS
- char str[KSYM_SYMBOL_LEN];
- const char *name;
-
- sprint_symbol(str, address);
- name = kretprobed(str);
-
- return trace_seq_printf(s, fmt, name);
-#endif
- return 1;
-}
-
-#ifndef CONFIG_64BIT
-# define IP_FMT "%08lx"
-#else
-# define IP_FMT "%016lx"
-#endif
-
-int
-seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
-{
- int ret;
-
- if (!ip)
- return trace_seq_printf(s, "0");
-
- if (sym_flags & TRACE_ITER_SYM_OFFSET)
- ret = seq_print_sym_offset(s, "%s", ip);
- else
- ret = seq_print_sym_short(s, "%s", ip);
-
- if (!ret)
- return 0;
-
- if (sym_flags & TRACE_ITER_SYM_ADDR)
- ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
- return ret;
-}
-
-static inline int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
- unsigned long ip, unsigned long sym_flags)
-{
- struct file *file = NULL;
- unsigned long vmstart = 0;
- int ret = 1;
-
- if (mm) {
- const struct vm_area_struct *vma;
-
- down_read(&mm->mmap_sem);
- vma = find_vma(mm, ip);
- if (vma) {
- file = vma->vm_file;
- vmstart = vma->vm_start;
- }
- if (file) {
- ret = trace_seq_path(s, &file->f_path);
- if (ret)
- ret = trace_seq_printf(s, "[+0x%lx]", ip - vmstart);
- }
- up_read(&mm->mmap_sem);
- }
- if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
- ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
- return ret;
-}
-
-static int
-seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
- unsigned long sym_flags)
-{
- struct mm_struct *mm = NULL;
- int ret = 1;
- unsigned int i;
-
- if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
- struct task_struct *task;
- /*
- * we do the lookup on the thread group leader,
- * since individual threads might have already quit!
- */
- rcu_read_lock();
- task = find_task_by_vpid(entry->ent.tgid);
- if (task)
- mm = get_task_mm(task);
- rcu_read_unlock();
- }
-
- for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
- unsigned long ip = entry->caller[i];
-
- if (ip == ULONG_MAX || !ret)
- break;
- if (i && ret)
- ret = trace_seq_puts(s, " <- ");
- if (!ip) {
- if (ret)
- ret = trace_seq_puts(s, "??");
- continue;
- }
- if (!ret)
- break;
- if (ret)
- ret = seq_print_user_ip(s, mm, ip, sym_flags);
- }
-
- if (mm)
- mmput(mm);
- return ret;
-}
-
static void print_lat_help_header(struct seq_file *m)
{
seq_puts(m, "# _------=> CPU# \n");
@@ -1755,52 +1482,6 @@ lat_print_timestamp(struct trace_seq *s, u64 abs_usecs,
trace_seq_puts(s, " : ");
}
-static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
-
-static int task_state_char(unsigned long state)
-{
- int bit = state ? __ffs(state) + 1 : 0;
-
- return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
-}
-
-/*
- * The message is supposed to contain an ending newline.
- * If the printing stops prematurely, try to add a newline of our own.
- */
-void trace_seq_print_cont(struct trace_seq *s, struct trace_iterator *iter)
-{
- struct trace_entry *ent;
- struct trace_field_cont *cont;
- bool ok = true;
-
- ent = peek_next_entry(iter, iter->cpu, NULL);
- if (!ent || ent->type != TRACE_CONT) {
- trace_seq_putc(s, '\n');
- return;
- }
-
- do {
- cont = (struct trace_field_cont *)ent;
- if (ok)
- ok = (trace_seq_printf(s, "%s", cont->buf) > 0);
-
- ftrace_disable_cpu();
-
- if (iter->buffer_iter[iter->cpu])
- ring_buffer_read(iter->buffer_iter[iter->cpu], NULL);
- else
- ring_buffer_consume(iter->tr->buffer, iter->cpu, NULL);
-
- ftrace_enable_cpu();
-
- ent = peek_next_entry(iter, iter->cpu, NULL);
- } while (ent && ent->type == TRACE_CONT);
-
- if (!ok)
- trace_seq_putc(s, '\n');
-}
-
static void test_cpu_buff_start(struct trace_iterator *iter)
{
struct trace_seq *s = &iter->seq;
@@ -1824,17 +1505,14 @@ print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu)
struct trace_seq *s = &iter->seq;
unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
struct trace_entry *next_entry;
+ struct trace_event *event;
unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
struct trace_entry *entry = iter->ent;
unsigned long abs_usecs;
unsigned long rel_usecs;
u64 next_ts;
char *comm;
- int S, T;
- int i;
-
- if (entry->type == TRACE_CONT)
- return TRACE_TYPE_HANDLED;
+ int ret;
test_cpu_buff_start(iter);
@@ -1859,96 +1537,16 @@ print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu)
lat_print_generic(s, entry, cpu);
lat_print_timestamp(s, abs_usecs, rel_usecs);
}
- switch (entry->type) {
- case TRACE_FN: {
- struct ftrace_entry *field;
-
- trace_assign_type(field, entry);
-
- seq_print_ip_sym(s, field->ip, sym_flags);
- trace_seq_puts(s, " (");
- seq_print_ip_sym(s, field->parent_ip, sym_flags);
- trace_seq_puts(s, ")\n");
- break;
- }
- case TRACE_CTX:
- case TRACE_WAKE: {
- struct ctx_switch_entry *field;
-
- trace_assign_type(field, entry);
-
- T = task_state_char(field->next_state);
- S = task_state_char(field->prev_state);
- comm = trace_find_cmdline(field->next_pid);
- trace_seq_printf(s, " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
- field->prev_pid,
- field->prev_prio,
- S, entry->type == TRACE_CTX ? "==>" : " +",
- field->next_cpu,
- field->next_pid,
- field->next_prio,
- T, comm);
- break;
- }
- case TRACE_SPECIAL: {
- struct special_entry *field;
-
- trace_assign_type(field, entry);
-
- trace_seq_printf(s, "# %ld %ld %ld\n",
- field->arg1,
- field->arg2,
- field->arg3);
- break;
- }
- case TRACE_STACK: {
- struct stack_entry *field;
-
- trace_assign_type(field, entry);
-
- for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
- if (i)
- trace_seq_puts(s, " <= ");
- seq_print_ip_sym(s, field->caller[i], sym_flags);
- }
- trace_seq_puts(s, "\n");
- break;
- }
- case TRACE_PRINT: {
- struct print_entry *field;
-
- trace_assign_type(field, entry);
- seq_print_ip_sym(s, field->ip, sym_flags);
- trace_seq_printf(s, ": %s", field->buf);
- if (entry->flags & TRACE_FLAG_CONT)
- trace_seq_print_cont(s, iter);
- break;
- }
- case TRACE_BRANCH: {
- struct trace_branch *field;
-
- trace_assign_type(field, entry);
-
- trace_seq_printf(s, "[%s] %s:%s:%d\n",
- field->correct ? " ok " : " MISS ",
- field->func,
- field->file,
- field->line);
- break;
+ event = ftrace_find_event(entry->type);
+ if (event && event->latency_trace) {
+ ret = event->latency_trace(s, entry, sym_flags);
+ if (ret)
+ return ret;
+ return TRACE_TYPE_HANDLED;
}
- case TRACE_USER_STACK: {
- struct userstack_entry *field;
-
- trace_assign_type(field, entry);
- seq_print_userip_objs(field, s, sym_flags);
- trace_seq_putc(s, '\n');
- break;
- }
- default:
- trace_seq_printf(s, "Unknown type %d\n", entry->type);
- }
+ trace_seq_printf(s, "Unknown type %d\n", entry->type);
return TRACE_TYPE_HANDLED;
}
@@ -1957,19 +1555,15 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
struct trace_seq *s = &iter->seq;
unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
struct trace_entry *entry;
+ struct trace_event *event;
unsigned long usec_rem;
unsigned long long t;
unsigned long secs;
char *comm;
int ret;
- int S, T;
- int i;
entry = iter->ent;
- if (entry->type == TRACE_CONT)
- return TRACE_TYPE_HANDLED;
-
test_cpu_buff_start(iter);
comm = trace_find_cmdline(iter->ent->pid);
@@ -1988,129 +1582,17 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
- switch (entry->type) {
- case TRACE_FN: {
- struct ftrace_entry *field;
-
- trace_assign_type(field, entry);
-
- ret = seq_print_ip_sym(s, field->ip, sym_flags);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- if ((sym_flags & TRACE_ITER_PRINT_PARENT) &&
- field->parent_ip) {
- ret = trace_seq_printf(s, " <-");
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- ret = seq_print_ip_sym(s,
- field->parent_ip,
- sym_flags);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- }
- ret = trace_seq_printf(s, "\n");
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- break;
- }
- case TRACE_CTX:
- case TRACE_WAKE: {
- struct ctx_switch_entry *field;
-
- trace_assign_type(field, entry);
-
- T = task_state_char(field->next_state);
- S = task_state_char(field->prev_state);
- ret = trace_seq_printf(s, " %5d:%3d:%c %s [%03d] %5d:%3d:%c\n",
- field->prev_pid,
- field->prev_prio,
- S,
- entry->type == TRACE_CTX ? "==>" : " +",
- field->next_cpu,
- field->next_pid,
- field->next_prio,
- T);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- break;
- }
- case TRACE_SPECIAL: {
- struct special_entry *field;
-
- trace_assign_type(field, entry);
-
- ret = trace_seq_printf(s, "# %ld %ld %ld\n",
- field->arg1,
- field->arg2,
- field->arg3);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- break;
- }
- case TRACE_STACK: {
- struct stack_entry *field;
-
- trace_assign_type(field, entry);
-
- for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
- if (i) {
- ret = trace_seq_puts(s, " <= ");
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- }
- ret = seq_print_ip_sym(s, field->caller[i],
- sym_flags);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- }
- ret = trace_seq_puts(s, "\n");
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- break;
- }
- case TRACE_PRINT: {
- struct print_entry *field;
-
- trace_assign_type(field, entry);
-
- seq_print_ip_sym(s, field->ip, sym_flags);
- trace_seq_printf(s, ": %s", field->buf);
- if (entry->flags & TRACE_FLAG_CONT)
- trace_seq_print_cont(s, iter);
- break;
- }
- case TRACE_GRAPH_RET: {
- return print_graph_function(iter);
- }
- case TRACE_GRAPH_ENT: {
- return print_graph_function(iter);
- }
- case TRACE_BRANCH: {
- struct trace_branch *field;
-
- trace_assign_type(field, entry);
-
- trace_seq_printf(s, "[%s] %s:%s:%d\n",
- field->correct ? " ok " : " MISS ",
- field->func,
- field->file,
- field->line);
- break;
+ event = ftrace_find_event(entry->type);
+ if (event && event->trace) {
+ ret = event->trace(s, entry, sym_flags);
+ if (ret)
+ return ret;
+ return TRACE_TYPE_HANDLED;
}
- case TRACE_USER_STACK: {
- struct userstack_entry *field;
-
- trace_assign_type(field, entry);
+ ret = trace_seq_printf(s, "Unknown type %d\n", entry->type);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
- ret = seq_print_userip_objs(field, s, sym_flags);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- ret = trace_seq_putc(s, '\n');
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- break;
- }
- }
return TRACE_TYPE_HANDLED;
}
@@ -2118,152 +1600,47 @@ static enum print_line_t print_raw_fmt(struct trace_iterator *iter)
{
struct trace_seq *s = &iter->seq;
struct trace_entry *entry;
+ struct trace_event *event;
int ret;
- int S, T;
entry = iter->ent;
- if (entry->type == TRACE_CONT)
- return TRACE_TYPE_HANDLED;
-
ret = trace_seq_printf(s, "%d %d %llu ",
entry->pid, iter->cpu, iter->ts);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
- switch (entry->type) {
- case TRACE_FN: {
- struct ftrace_entry *field;
-
- trace_assign_type(field, entry);
-
- ret = trace_seq_printf(s, "%x %x\n",
- field->ip,
- field->parent_ip);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- break;
- }
- case TRACE_CTX:
- case TRACE_WAKE: {
- struct ctx_switch_entry *field;
-
- trace_assign_type(field, entry);
-
- T = task_state_char(field->next_state);
- S = entry->type == TRACE_WAKE ? '+' :
- task_state_char(field->prev_state);
- ret = trace_seq_printf(s, "%d %d %c %d %d %d %c\n",
- field->prev_pid,
- field->prev_prio,
- S,
- field->next_cpu,
- field->next_pid,
- field->next_prio,
- T);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- break;
- }
- case TRACE_SPECIAL:
- case TRACE_USER_STACK:
- case TRACE_STACK: {
- struct special_entry *field;
-
- trace_assign_type(field, entry);
-
- ret = trace_seq_printf(s, "# %ld %ld %ld\n",
- field->arg1,
- field->arg2,
- field->arg3);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- break;
+ event = ftrace_find_event(entry->type);
+ if (event && event->raw) {
+ ret = event->raw(s, entry, 0);
+ if (ret)
+ return ret;
+ return TRACE_TYPE_HANDLED;
}
- case TRACE_PRINT: {
- struct print_entry *field;
-
- trace_assign_type(field, entry);
+ ret = trace_seq_printf(s, "%d ?\n", entry->type);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
- trace_seq_printf(s, "# %lx %s", field->ip, field->buf);
- if (entry->flags & TRACE_FLAG_CONT)
- trace_seq_print_cont(s, iter);
- break;
- }
- }
return TRACE_TYPE_HANDLED;
}
-#define SEQ_PUT_FIELD_RET(s, x) \
-do { \
- if (!trace_seq_putmem(s, &(x), sizeof(x))) \
- return 0; \
-} while (0)
-
-#define SEQ_PUT_HEX_FIELD_RET(s, x) \
-do { \
- BUILD_BUG_ON(sizeof(x) > MAX_MEMHEX_BYTES); \
- if (!trace_seq_putmem_hex(s, &(x), sizeof(x))) \
- return 0; \
-} while (0)
-
static enum print_line_t print_hex_fmt(struct trace_iterator *iter)
{
struct trace_seq *s = &iter->seq;
unsigned char newline = '\n';
struct trace_entry *entry;
- int S, T;
+ struct trace_event *event;
entry = iter->ent;
- if (entry->type == TRACE_CONT)
- return TRACE_TYPE_HANDLED;
-
SEQ_PUT_HEX_FIELD_RET(s, entry->pid);
SEQ_PUT_HEX_FIELD_RET(s, iter->cpu);
SEQ_PUT_HEX_FIELD_RET(s, iter->ts);
- switch (entry->type) {
- case TRACE_FN: {
- struct ftrace_entry *field;
+ event = ftrace_find_event(entry->type);
+ if (event && event->hex)
+ event->hex(s, entry, 0);
- trace_assign_type(field, entry);
-
- SEQ_PUT_HEX_FIELD_RET(s, field->ip);
- SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
- break;
- }
- case TRACE_CTX:
- case TRACE_WAKE: {
- struct ctx_switch_entry *field;
-
- trace_assign_type(field, entry);
-
- T = task_state_char(field->next_state);
- S = entry->type == TRACE_WAKE ? '+' :
- task_state_char(field->prev_state);
- SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
- SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
- SEQ_PUT_HEX_FIELD_RET(s, S);
- SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
- SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
- SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
- SEQ_PUT_HEX_FIELD_RET(s, T);
- break;
- }
- case TRACE_SPECIAL:
- case TRACE_USER_STACK:
- case TRACE_STACK: {
- struct special_entry *field;
-
- trace_assign_type(field, entry);
-
- SEQ_PUT_HEX_FIELD_RET(s, field->arg1);
- SEQ_PUT_HEX_FIELD_RET(s, field->arg2);
- SEQ_PUT_HEX_FIELD_RET(s, field->arg3);
- break;
- }
- }
SEQ_PUT_FIELD_RET(s, newline);
return TRACE_TYPE_HANDLED;
@@ -2282,9 +1659,6 @@ static enum print_line_t print_printk_msg_only(struct trace_iterator *iter)
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
- if (entry->flags & TRACE_FLAG_CONT)
- trace_seq_print_cont(s, iter);
-
return TRACE_TYPE_HANDLED;
}
@@ -2292,53 +1666,19 @@ static enum print_line_t print_bin_fmt(struct trace_iterator *iter)
{
struct trace_seq *s = &iter->seq;
struct trace_entry *entry;
+ struct trace_event *event;
entry = iter->ent;
- if (entry->type == TRACE_CONT)
- return TRACE_TYPE_HANDLED;
-
SEQ_PUT_FIELD_RET(s, entry->pid);
SEQ_PUT_FIELD_RET(s, entry->cpu);
SEQ_PUT_FIELD_RET(s, iter->ts);
- switch (entry->type) {
- case TRACE_FN: {
- struct ftrace_entry *field;
-
- trace_assign_type(field, entry);
-
- SEQ_PUT_FIELD_RET(s, field->ip);
- SEQ_PUT_FIELD_RET(s, field->parent_ip);
- break;
- }
- case TRACE_CTX: {
- struct ctx_switch_entry *field;
-
- trace_assign_type(field, entry);
-
- SEQ_PUT_FIELD_RET(s, field->prev_pid);
- SEQ_PUT_FIELD_RET(s, field->prev_prio);
- SEQ_PUT_FIELD_RET(s, field->prev_state);
- SEQ_PUT_FIELD_RET(s, field->next_pid);
- SEQ_PUT_FIELD_RET(s, field->next_prio);
- SEQ_PUT_FIELD_RET(s, field->next_state);
- break;
- }
- case TRACE_SPECIAL:
- case TRACE_USER_STACK:
- case TRACE_STACK: {
- struct special_entry *field;
-
- trace_assign_type(field, entry);
+ event = ftrace_find_event(entry->type);
+ if (event && event->binary)
+ event->binary(s, entry, 0);
- SEQ_PUT_FIELD_RET(s, field->arg1);
- SEQ_PUT_FIELD_RET(s, field->arg2);
- SEQ_PUT_FIELD_RET(s, field->arg3);
- break;
- }
- }
- return 1;
+ return TRACE_TYPE_HANDLED;
}
static int trace_empty(struct trace_iterator *iter)
@@ -3013,6 +2353,7 @@ static int tracing_set_tracer(char *buf)
if (ret)
goto out;
}
+ init_tracer_stat(t);
trace_branch_enable(tr);
out:
@@ -3877,7 +3218,7 @@ __init static int tracer_alloc_buffers(void)
#else
current_trace = &nop_trace;
#endif
-
+ init_tracer_stat(current_trace);
/* All seems OK, enable tracing */
tracing_disabled = 0;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 742fe134927..94ed45e93a8 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -17,7 +17,6 @@ enum trace_type {
TRACE_FN,
TRACE_CTX,
TRACE_WAKE,
- TRACE_CONT,
TRACE_STACK,
TRACE_PRINT,
TRACE_SPECIAL,
@@ -34,7 +33,7 @@ enum trace_type {
TRACE_KMEM_FREE,
TRACE_POWER,
- __TRACE_LAST_TYPE
+ __TRACE_LAST_TYPE,
};
/*
@@ -199,7 +198,6 @@ struct kmemtrace_free_entry {
* NEED_RESCED - reschedule is requested
* HARDIRQ - inside an interrupt handler
* SOFTIRQ - inside a softirq handler
- * CONT - multiple entries hold the trace item
*/
enum trace_flag_type {
TRACE_FLAG_IRQS_OFF = 0x01,
@@ -207,7 +205,6 @@ enum trace_flag_type {
TRACE_FLAG_NEED_RESCHED = 0x04,
TRACE_FLAG_HARDIRQ = 0x08,
TRACE_FLAG_SOFTIRQ = 0x10,
- TRACE_FLAG_CONT = 0x20,
};
#define TRACE_BUF_SIZE 1024
@@ -283,7 +280,6 @@ extern void __ftrace_bad_type(void);
do { \
IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
- IF_ASSIGN(var, ent, struct trace_field_cont, TRACE_CONT); \
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); \
@@ -365,6 +361,21 @@ struct tracer {
struct tracer *next;
int print_max;
struct tracer_flags *flags;
+
+ /*
+ * If you change one of the following on tracing runtime, recall
+ * init_tracer_stat()
+ */
+
+ /* Iteration over statistic entries */
+ void *(*stat_start)(void);
+ void *(*stat_next)(void *prev, int idx);
+ /* Compare two entries for sorting (optional) for stats */
+ int (*stat_cmp)(void *p1, void *p2);
+ /* Print a stat entry */
+ int (*stat_show)(struct seq_file *s, void *p);
+ /* Print the headers of your stat entries */
+ int (*stat_headers)(struct seq_file *s);
};
struct trace_seq {
@@ -450,6 +461,8 @@ void tracing_start_sched_switch_record(void);
int register_tracer(struct tracer *type);
void unregister_tracer(struct tracer *type);
+void init_tracer_stat(struct tracer *trace);
+
extern unsigned long nsecs_to_usecs(unsigned long nsecs);
extern unsigned long tracing_max_latency;
@@ -481,10 +494,10 @@ struct tracer_switch_ops {
void *private;
struct tracer_switch_ops *next;
};
-
-char *trace_find_cmdline(int pid);
#endif /* CONFIG_CONTEXT_SWITCH_TRACER */
+extern char *trace_find_cmdline(int pid);
+
#ifdef CONFIG_DYNAMIC_FTRACE
extern unsigned long ftrace_update_tot_cnt;
#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
@@ -513,15 +526,6 @@ extern int trace_selftest_startup_branch(struct tracer *trace,
#endif /* CONFIG_FTRACE_STARTUP_TEST */
extern void *head_page(struct trace_array_cpu *data);
-extern int trace_seq_printf(struct trace_seq *s, const char *fmt, ...);
-extern void trace_seq_print_cont(struct trace_seq *s,
- struct trace_iterator *iter);
-
-extern int
-seq_print_ip_sym(struct trace_seq *s, unsigned long ip,
- unsigned long sym_flags);
-extern ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
- size_t cnt);
extern long ns2usecs(cycle_t nsec);
extern int
trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args);
diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
index 366c8c333e1..0e94b3d091f 100644
--- a/kernel/trace/trace_boot.c
+++ b/kernel/trace/trace_boot.c
@@ -11,6 +11,7 @@
#include <linux/kallsyms.h>
#include "trace.h"
+#include "trace_output.h"
static struct trace_array *boot_trace;
static bool pre_initcalls_finished;
diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c
index 6c00feb3bac..4785a3b9bc4 100644
--- a/kernel/trace/trace_branch.c
+++ b/kernel/trace/trace_branch.c
@@ -14,12 +14,17 @@
#include <linux/hash.h>
#include <linux/fs.h>
#include <asm/local.h>
+
#include "trace.h"
+#include "trace_output.h"
+
+static struct tracer branch_trace;
#ifdef CONFIG_BRANCH_TRACER
static int branch_tracing_enabled __read_mostly;
static DEFINE_MUTEX(branch_tracing_mutex);
+
static struct trace_array *branch_tracer;
static void
@@ -142,22 +147,50 @@ static void branch_trace_reset(struct trace_array *tr)
stop_branch_trace(tr);
}
-struct tracer branch_trace __read_mostly =
+static int
+trace_print_print(struct trace_seq *s, struct trace_entry *entry, int flags)
{
- .name = "branch",
- .init = branch_trace_init,
- .reset = branch_trace_reset,
-#ifdef CONFIG_FTRACE_SELFTEST
- .selftest = trace_selftest_startup_branch,
-#endif
-};
+ struct print_entry *field;
-__init static int init_branch_trace(void)
+ trace_assign_type(field, entry);
+
+ if (seq_print_ip_sym(s, field->ip, flags))
+ goto partial;
+
+ if (trace_seq_printf(s, ": %s", field->buf))
+ goto partial;
+
+ partial:
+ return TRACE_TYPE_PARTIAL_LINE;
+}
+
+static int
+trace_branch_print(struct trace_seq *s, struct trace_entry *entry, int flags)
{
- return register_tracer(&branch_trace);
+ struct trace_branch *field;
+
+ trace_assign_type(field, entry);
+
+ if (trace_seq_printf(s, "[%s] %s:%s:%d\n",
+ field->correct ? " ok " : " MISS ",
+ field->func,
+ field->file,
+ field->line))
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return 0;
}
-device_initcall(init_branch_trace);
+
+static struct trace_event trace_branch_event = {
+ .type = TRACE_BRANCH,
+ .trace = trace_branch_print,
+ .latency_trace = trace_branch_print,
+ .raw = trace_nop_print,
+ .hex = trace_nop_print,
+ .binary = trace_nop_print,
+};
+
#else
static inline
void trace_likely_condition(struct ftrace_branch_data *f, int val, int expect)
@@ -183,66 +216,39 @@ void ftrace_likely_update(struct ftrace_branch_data *f, int val, int expect)
}
EXPORT_SYMBOL(ftrace_likely_update);
-struct ftrace_pointer {
- void *start;
- void *stop;
- int hit;
-};
+extern unsigned long __start_annotated_branch_profile[];
+extern unsigned long __stop_annotated_branch_profile[];
-static void *
-t_next(struct seq_file *m, void *v, loff_t *pos)
+static int annotated_branch_stat_headers(struct seq_file *m)
{
- const struct ftrace_pointer *f = m->private;
- struct ftrace_branch_data *p = v;
-
- (*pos)++;
-
- if (v == (void *)1)
- return f->start;
-
- ++p;
-
- if ((void *)p >= (void *)f->stop)
- return NULL;
-
- return p;
+ seq_printf(m, " correct incorrect %% ");
+ seq_printf(m, " Function "
+ " File Line\n"
+ " ------- --------- - "
+ " -------- "
+ " ---- ----\n");
+ return 0;
}
-static void *t_start(struct seq_file *m, loff_t *pos)
+static inline long get_incorrect_percent(struct ftrace_branch_data *p)
{
- void *t = (void *)1;
- loff_t l = 0;
-
- for (; t && l < *pos; t = t_next(m, t, &l))
- ;
+ long percent;
- return t;
-}
+ if (p->correct) {
+ percent = p->incorrect * 100;
+ percent /= p->correct + p->incorrect;
+ } else
+ percent = p->incorrect ? 100 : -1;
-static void t_stop(struct seq_file *m, void *p)
-{
+ return percent;
}
-static int t_show(struct seq_file *m, void *v)
+static int branch_stat_show(struct seq_file *m, void *v)
{
- const struct ftrace_pointer *fp = m->private;
struct ftrace_branch_data *p = v;
const char *f;
long percent;
- if (v == (void *)1) {
- if (fp->hit)
- seq_printf(m, " miss hit %% ");
- else
- seq_printf(m, " correct incorrect %% ");
- seq_printf(m, " Function "
- " File Line\n"
- " ------- --------- - "
- " -------- "
- " ---- ----\n");
- return 0;
- }
-
/* Only print the file, not the path */
f = p->file + strlen(p->file);
while (f >= p->file && *f != '/')
@@ -252,11 +258,7 @@ static int t_show(struct seq_file *m, void *v)
/*
* The miss is overlayed on correct, and hit on incorrect.
*/
- if (p->correct) {
- percent = p->incorrect * 100;
- percent /= p->correct + p->incorrect;
- } else
- percent = p->incorrect ? 100 : -1;
+ percent = get_incorrect_percent(p);
seq_printf(m, "%8lu %8lu ", p->correct, p->incorrect);
if (percent < 0)
@@ -267,76 +269,143 @@ static int t_show(struct seq_file *m, void *v)
return 0;
}
-static struct seq_operations tracing_likely_seq_ops = {
- .start = t_start,
- .next = t_next,
- .stop = t_stop,
- .show = t_show,
-};
+static void *annotated_branch_stat_start(void)
+{
+ return __start_annotated_branch_profile;
+}
-static int tracing_branch_open(struct inode *inode, struct file *file)
+static void *
+annotated_branch_stat_next(void *v, int idx)
{
- int ret;
+ struct ftrace_branch_data *p = v;
- ret = seq_open(file, &tracing_likely_seq_ops);
- if (!ret) {
- struct seq_file *m = file->private_data;
- m->private = (void *)inode->i_private;
- }
+ ++p;
- return ret;
+ if ((void *)p >= (void *)__stop_annotated_branch_profile)
+ return NULL;
+
+ return p;
}
-static const struct file_operations tracing_branch_fops = {
- .open = tracing_branch_open,
- .read = seq_read,
- .llseek = seq_lseek,
-};
+static int annotated_branch_stat_cmp(void *p1, void *p2)
+{
+ struct ftrace_branch_data *a = p1;
+ struct ftrace_branch_data *b = p2;
+
+ long percent_a, percent_b;
+
+ percent_a = get_incorrect_percent(a);
+ percent_b = get_incorrect_percent(b);
+
+ if (percent_a < percent_b)
+ return -1;
+ if (percent_a > percent_b)
+ return 1;
+ else
+ return 0;
+}
#ifdef CONFIG_PROFILE_ALL_BRANCHES
-extern unsigned long __start_branch_profile[];
-extern unsigned long __stop_branch_profile[];
+enum {
+ TRACE_BRANCH_OPT_ALL = 0x1
+};
-static const struct ftrace_pointer ftrace_branch_pos = {
- .start = __start_branch_profile,
- .stop = __stop_branch_profile,
- .hit = 1,
+static struct tracer_opt branch_opts[] = {
+ { TRACER_OPT(stat_all_branch, TRACE_BRANCH_OPT_ALL) },
+ { }
};
-#endif /* CONFIG_PROFILE_ALL_BRANCHES */
+static struct tracer_flags branch_flags = {
+ .val = 0,
+ .opts = branch_opts
+};
-extern unsigned long __start_annotated_branch_profile[];
-extern unsigned long __stop_annotated_branch_profile[];
+extern unsigned long __start_branch_profile[];
+extern unsigned long __stop_branch_profile[];
-static const struct ftrace_pointer ftrace_annotated_branch_pos = {
- .start = __start_annotated_branch_profile,
- .stop = __stop_annotated_branch_profile,
-};
+static int all_branch_stat_headers(struct seq_file *m)
+{
+ seq_printf(m, " miss hit %% ");
+ seq_printf(m, " Function "
+ " File Line\n"
+ " ------- --------- - "
+ " -------- "
+ " ---- ----\n");
+ return 0;
+}
+
+static void *all_branch_stat_start(void)
+{
+ return __start_branch_profile;
+}
-static __init int ftrace_branch_init(void)
+static void *
+all_branch_stat_next(void *v, int idx)
{
- struct dentry *d_tracer;
- struct dentry *entry;
+ struct ftrace_branch_data *p = v;
- d_tracer = tracing_init_dentry();
+ ++p;
- entry = debugfs_create_file("profile_annotated_branch", 0444, d_tracer,
- (void *)&ftrace_annotated_branch_pos,
- &tracing_branch_fops);
- if (!entry)
- pr_warning("Could not create debugfs "
- "'profile_annotatet_branch' entry\n");
+ if ((void *)p >= (void *)__stop_branch_profile)
+ return NULL;
-#ifdef CONFIG_PROFILE_ALL_BRANCHES
- entry = debugfs_create_file("profile_branch", 0444, d_tracer,
- (void *)&ftrace_branch_pos,
- &tracing_branch_fops);
- if (!entry)
- pr_warning("Could not create debugfs"
- " 'profile_branch' entry\n");
-#endif
+ return p;
+}
+static int branch_set_flag(u32 old_flags, u32 bit, int set)
+{
+ if (bit == TRACE_BRANCH_OPT_ALL) {
+ if (set) {
+ branch_trace.stat_headers = all_branch_stat_headers;
+ branch_trace.stat_start = all_branch_stat_start;
+ branch_trace.stat_next = all_branch_stat_next;
+ branch_trace.stat_cmp = NULL;
+ } else {
+ branch_trace.stat_headers =
+ annotated_branch_stat_headers;
+ branch_trace.stat_start = annotated_branch_stat_start;
+ branch_trace.stat_next = annotated_branch_stat_next;
+ branch_trace.stat_cmp = annotated_branch_stat_cmp;
+ }
+ init_tracer_stat(&branch_trace);
+ }
return 0;
}
-device_initcall(ftrace_branch_init);
+#endif /* CONFIG_PROFILE_ALL_BRANCHES */
+
+static struct tracer branch_trace __read_mostly =
+{
+ .name = "branch",
+#ifdef CONFIG_BRANCH_TRACER
+ .init = branch_trace_init,
+ .reset = branch_trace_reset,
+#ifdef CONFIG_FTRACE_SELFTEST
+ .selftest = trace_selftest_startup_branch,
+#endif /* CONFIG_FTRACE_SELFTEST */
+#endif /* CONFIG_BRANCH_TRACER */
+ .stat_start = annotated_branch_stat_start,
+ .stat_next = annotated_branch_stat_next,
+ .stat_show = branch_stat_show,
+ .stat_headers = annotated_branch_stat_headers,
+ .stat_cmp = annotated_branch_stat_cmp,
+#ifdef CONFIG_PROFILE_ALL_BRANCHES
+ .flags = &branch_flags,
+ .set_flag = branch_set_flag,
+#endif
+};
+
+__init static int init_branch_trace(void)
+{
+#ifdef CONFIG_BRANCH_TRACER
+ int ret;
+ ret = register_ftrace_event(&trace_branch_event);
+ if (!ret) {
+ printk(KERN_WARNING "Warning: could not register branch events\n");
+ return 1;
+ }
+#endif
+
+ return register_tracer(&branch_trace);
+}
+device_initcall(init_branch_trace);
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 8516e4f09e1..3c545984816 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -12,6 +12,7 @@
#include <linux/fs.h>
#include "trace.h"
+#include "trace_output.h"
#define TRACE_GRAPH_INDENT 2
@@ -589,9 +590,6 @@ print_graph_comment(struct print_entry *trace, struct trace_seq *s,
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
- if (ent->flags & TRACE_FLAG_CONT)
- trace_seq_print_cont(s, iter);
-
/* Strip ending newline */
if (s->buffer[s->len - 1] == '\n') {
s->buffer[s->len - 1] = '\0';
diff --git a/kernel/trace/trace_hw_branches.c b/kernel/trace/trace_hw_branches.c
index 649df22d435..df21c1e72b9 100644
--- a/kernel/trace/trace_hw_branches.c
+++ b/kernel/trace/trace_hw_branches.c
@@ -14,6 +14,7 @@
#include <asm/ds.h>
#include "trace.h"
+#include "trace_output.h"
#define SIZEOF_BTS (1 << 13)
diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c
index fffcb069f1d..fcec59ff235 100644
--- a/kernel/trace/trace_mmiotrace.c
+++ b/kernel/trace/trace_mmiotrace.c
@@ -11,6 +11,7 @@
#include <linux/pci.h>
#include "trace.h"
+#include "trace_output.h"
struct header_iter {
struct pci_dev *dev;
@@ -262,9 +263,6 @@ static enum print_line_t mmio_print_mark(struct trace_iterator *iter)
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
- if (entry->flags & TRACE_FLAG_CONT)
- trace_seq_print_cont(s, iter);
-
return TRACE_TYPE_HANDLED;
}
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
new file mode 100644
index 00000000000..df0c25cbed3
--- /dev/null
+++ b/kernel/trace/trace_output.c
@@ -0,0 +1,832 @@
+/*
+ * trace_output.c
+ *
+ * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/ftrace.h>
+
+#include "trace_output.h"
+
+/* must be a power of 2 */
+#define EVENT_HASHSIZE 128
+
+static DEFINE_MUTEX(trace_event_mutex);
+static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
+
+static int next_event_type = __TRACE_LAST_TYPE + 1;
+
+/**
+ * trace_seq_printf - sequence printing of trace information
+ * @s: trace sequence descriptor
+ * @fmt: printf format string
+ *
+ * The tracer may use either sequence operations or its own
+ * copy to user routines. To simplify formating of a trace
+ * trace_seq_printf is used to store strings into a special
+ * buffer (@s). Then the output may be either used by
+ * the sequencer or pulled into another buffer.
+ */
+int
+trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
+{
+ int len = (PAGE_SIZE - 1) - s->len;
+ va_list ap;
+ int ret;
+
+ if (!len)
+ return 0;
+
+ va_start(ap, fmt);
+ ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
+ va_end(ap);
+
+ /* If we can't write it all, don't bother writing anything */
+ if (ret >= len)
+ return 0;
+
+ s->len += ret;
+
+ return len;
+}
+
+/**
+ * trace_seq_puts - trace sequence printing of simple string
+ * @s: trace sequence descriptor
+ * @str: simple string to record
+ *
+ * The tracer may use either the sequence operations or its own
+ * copy to user routines. This function records a simple string
+ * into a special buffer (@s) for later retrieval by a sequencer
+ * or other mechanism.
+ */
+int trace_seq_puts(struct trace_seq *s, const char *str)
+{
+ int len = strlen(str);
+
+ if (len > ((PAGE_SIZE - 1) - s->len))
+ return 0;
+
+ memcpy(s->buffer + s->len, str, len);
+ s->len += len;
+
+ return len;
+}
+
+int trace_seq_putc(struct trace_seq *s, unsigned char c)
+{
+ if (s->len >= (PAGE_SIZE - 1))
+ return 0;
+
+ s->buffer[s->len++] = c;
+
+ return 1;
+}
+
+int trace_seq_putmem(struct trace_seq *s, void *mem, size_t len)
+{
+ if (len > ((PAGE_SIZE - 1) - s->len))
+ return 0;
+
+ memcpy(s->buffer + s->len, mem, len);
+ s->len += len;
+
+ return len;
+}
+
+int trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len)
+{
+ unsigned char hex[HEX_CHARS];
+ unsigned char *data = mem;
+ int i, j;
+
+#ifdef __BIG_ENDIAN
+ for (i = 0, j = 0; i < len; i++) {
+#else
+ for (i = len-1, j = 0; i >= 0; i--) {
+#endif
+ hex[j++] = hex_asc_hi(data[i]);
+ hex[j++] = hex_asc_lo(data[i]);
+ }
+ hex[j++] = ' ';
+
+ return trace_seq_putmem(s, hex, j);
+}
+
+int trace_seq_path(struct trace_seq *s, struct path *path)
+{
+ unsigned char *p;
+
+ if (s->len >= (PAGE_SIZE - 1))
+ return 0;
+ p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
+ if (!IS_ERR(p)) {
+ p = mangle_path(s->buffer + s->len, p, "\n");
+ if (p) {
+ s->len = p - s->buffer;
+ return 1;
+ }
+ } else {
+ s->buffer[s->len++] = '?';
+ return 1;
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_KRETPROBES
+static inline const char *kretprobed(const char *name)
+{
+ static const char tramp_name[] = "kretprobe_trampoline";
+ int size = sizeof(tramp_name);
+
+ if (strncmp(tramp_name, name, size) == 0)
+ return "[unknown/kretprobe'd]";
+ return name;
+}
+#else
+static inline const char *kretprobed(const char *name)
+{
+ return name;
+}
+#endif /* CONFIG_KRETPROBES */
+
+static int
+seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
+{
+#ifdef CONFIG_KALLSYMS
+ char str[KSYM_SYMBOL_LEN];
+ const char *name;
+
+ kallsyms_lookup(address, NULL, NULL, NULL, str);
+
+ name = kretprobed(str);
+
+ return trace_seq_printf(s, fmt, name);
+#endif
+ return 1;
+}
+
+static int
+seq_print_sym_offset(struct trace_seq *s, const char *fmt,
+ unsigned long address)
+{
+#ifdef CONFIG_KALLSYMS
+ char str[KSYM_SYMBOL_LEN];
+ const char *name;
+
+ sprint_symbol(str, address);
+ name = kretprobed(str);
+
+ return trace_seq_printf(s, fmt, name);
+#endif
+ return 1;
+}
+
+#ifndef CONFIG_64BIT
+# define IP_FMT "%08lx"
+#else
+# define IP_FMT "%016lx"
+#endif
+
+int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
+ unsigned long ip, unsigned long sym_flags)
+{
+ struct file *file = NULL;
+ unsigned long vmstart = 0;
+ int ret = 1;
+
+ if (mm) {
+ const struct vm_area_struct *vma;
+
+ down_read(&mm->mmap_sem);
+ vma = find_vma(mm, ip);
+ if (vma) {
+ file = vma->vm_file;
+ vmstart = vma->vm_start;
+ }
+ if (file) {
+ ret = trace_seq_path(s, &file->f_path);
+ if (ret)
+ ret = trace_seq_printf(s, "[+0x%lx]",
+ ip - vmstart);
+ }
+ up_read(&mm->mmap_sem);
+ }
+ if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
+ ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
+ return ret;
+}
+
+int
+seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
+ unsigned long sym_flags)
+{
+ struct mm_struct *mm = NULL;
+ int ret = 1;
+ unsigned int i;
+
+ if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
+ struct task_struct *task;
+ /*
+ * we do the lookup on the thread group leader,
+ * since individual threads might have already quit!
+ */
+ rcu_read_lock();
+ task = find_task_by_vpid(entry->ent.tgid);
+ if (task)
+ mm = get_task_mm(task);
+ rcu_read_unlock();
+ }
+
+ for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
+ unsigned long ip = entry->caller[i];
+
+ if (ip == ULONG_MAX || !ret)
+ break;
+ if (i && ret)
+ ret = trace_seq_puts(s, " <- ");
+ if (!ip) {
+ if (ret)
+ ret = trace_seq_puts(s, "??");
+ continue;
+ }
+ if (!ret)
+ break;
+ if (ret)
+ ret = seq_print_user_ip(s, mm, ip, sym_flags);
+ }
+
+ if (mm)
+ mmput(mm);
+ return ret;
+}
+
+int
+seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
+{
+ int ret;
+
+ if (!ip)
+ return trace_seq_printf(s, "0");
+
+ if (sym_flags & TRACE_ITER_SYM_OFFSET)
+ ret = seq_print_sym_offset(s, "%s", ip);
+ else
+ ret = seq_print_sym_short(s, "%s", ip);
+
+ if (!ret)
+ return 0;
+
+ if (sym_flags & TRACE_ITER_SYM_ADDR)
+ ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
+ return ret;
+}
+
+static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
+
+static int task_state_char(unsigned long state)
+{
+ int bit = state ? __ffs(state) + 1 : 0;
+
+ return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
+}
+
+/**
+ * ftrace_find_event - find a registered event
+ * @type: the type of event to look for
+ *
+ * Returns an event of type @type otherwise NULL
+ */
+struct trace_event *ftrace_find_event(int type)
+{
+ struct trace_event *event;
+ struct hlist_node *n;
+ unsigned key;
+
+ key = type & (EVENT_HASHSIZE - 1);
+
+ hlist_for_each_entry_rcu(event, n, &event_hash[key], node) {
+ if (event->type == type)
+ return event;
+ }
+
+ return NULL;
+}
+
+/**
+ * register_ftrace_event - register output for an event type
+ * @event: the event type to register
+ *
+ * Event types are stored in a hash and this hash is used to
+ * find a way to print an event. If the @event->type is set
+ * then it will use that type, otherwise it will assign a
+ * type to use.
+ *
+ * If you assign your own type, please make sure it is added
+ * to the trace_type enum in trace.h, to avoid collisions
+ * with the dynamic types.
+ *
+ * Returns the event type number or zero on error.
+ */
+int register_ftrace_event(struct trace_event *event)
+{
+ unsigned key;
+ int ret = 0;
+
+ mutex_lock(&trace_event_mutex);
+
+ if (!event->type)
+ event->type = next_event_type++;
+ else if (event->type > __TRACE_LAST_TYPE) {
+ printk(KERN_WARNING "Need to add type to trace.h\n");
+ WARN_ON(1);
+ }
+
+ if (ftrace_find_event(event->type))
+ goto out;
+
+ key = event->type & (EVENT_HASHSIZE - 1);
+
+ hlist_add_head_rcu(&event->node, &event_hash[key]);
+
+ ret = event->type;
+ out:
+ mutex_unlock(&trace_event_mutex);
+
+ return ret;
+}
+
+/**
+ * unregister_ftrace_event - remove a no longer used event
+ * @event: the event to remove
+ */
+int unregister_ftrace_event(struct trace_event *event)
+{
+ mutex_lock(&trace_event_mutex);
+ hlist_del(&event->node);
+ mutex_unlock(&trace_event_mutex);
+
+ return 0;
+}
+
+/*
+ * Standard events
+ */
+
+int
+trace_nop_print(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ return 0;
+}
+
+/* TRACE_FN */
+static int
+trace_fn_latency(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct ftrace_entry *field;
+
+ trace_assign_type(field, entry);
+
+ if (!seq_print_ip_sym(s, field->ip, flags))
+ goto partial;
+ if (!trace_seq_puts(s, " ("))
+ goto partial;
+ if (!seq_print_ip_sym(s, field->parent_ip, flags))
+ goto partial;
+ if (!trace_seq_puts(s, ")\n"))
+ goto partial;
+
+ return 0;
+
+ partial:
+ return TRACE_TYPE_PARTIAL_LINE;
+}
+
+static int
+trace_fn_trace(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct ftrace_entry *field;
+
+ trace_assign_type(field, entry);
+
+ if (!seq_print_ip_sym(s, field->ip, flags))
+ goto partial;
+
+ if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
+ if (!trace_seq_printf(s, " <-"))
+ goto partial;
+ if (!seq_print_ip_sym(s,
+ field->parent_ip,
+ flags))
+ goto partial;
+ }
+ if (!trace_seq_printf(s, "\n"))
+ goto partial;
+
+ return 0;
+
+ partial:
+ return TRACE_TYPE_PARTIAL_LINE;
+}
+
+static int
+trace_fn_raw(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct ftrace_entry *field;
+
+ trace_assign_type(field, entry);
+
+ if (trace_seq_printf(s, "%x %x\n",
+ field->ip,
+ field->parent_ip))
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return 0;
+}
+
+static int
+trace_fn_hex(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct ftrace_entry *field;
+
+ trace_assign_type(field, entry);
+
+ SEQ_PUT_HEX_FIELD_RET(s, field->ip);
+ SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
+
+ return 0;
+}
+
+static int
+trace_fn_bin(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct ftrace_entry *field;
+
+ trace_assign_type(field, entry);
+
+ SEQ_PUT_FIELD_RET(s, field->ip);
+ SEQ_PUT_FIELD_RET(s, field->parent_ip);
+
+ return 0;
+}
+
+static struct trace_event trace_fn_event = {
+ .type = TRACE_FN,
+ .trace = trace_fn_trace,
+ .latency_trace = trace_fn_latency,
+ .raw = trace_fn_raw,
+ .hex = trace_fn_hex,
+ .binary = trace_fn_bin,
+};
+
+/* TRACE_CTX an TRACE_WAKE */
+static int
+trace_ctxwake_print(struct trace_seq *s, struct trace_entry *entry, int flags,
+ char *delim)
+{
+ struct ctx_switch_entry *field;
+ char *comm;
+ int S, T;
+
+ trace_assign_type(field, entry);
+
+ T = task_state_char(field->next_state);
+ S = task_state_char(field->prev_state);
+ comm = trace_find_cmdline(field->next_pid);
+ if (trace_seq_printf(s, " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
+ field->prev_pid,
+ field->prev_prio,
+ S, delim,
+ field->next_cpu,
+ field->next_pid,
+ field->next_prio,
+ T, comm))
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return 0;
+}
+
+static int
+trace_ctx_print(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ return trace_ctxwake_print(s, entry, flags, "==>");
+}
+
+static int
+trace_wake_print(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ return trace_ctxwake_print(s, entry, flags, " +");
+}
+
+static int
+trace_ctxwake_raw(struct trace_seq *s, struct trace_entry *entry, int flags,
+ char S)
+{
+ struct ctx_switch_entry *field;
+ int T;
+
+ trace_assign_type(field, entry);
+
+ if (!S)
+ task_state_char(field->prev_state);
+ T = task_state_char(field->next_state);
+ if (trace_seq_printf(s, "%d %d %c %d %d %d %c\n",
+ field->prev_pid,
+ field->prev_prio,
+ S,
+ field->next_cpu,
+ field->next_pid,
+ field->next_prio,
+ T))
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return 0;
+}
+
+static int
+trace_ctx_raw(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ return trace_ctxwake_raw(s, entry, flags, 0);
+}
+
+static int
+trace_wake_raw(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ return trace_ctxwake_raw(s, entry, flags, '+');
+}
+
+
+static int
+trace_ctxwake_hex(struct trace_seq *s, struct trace_entry *entry, int flags,
+ char S)
+{
+ struct ctx_switch_entry *field;
+ int T;
+
+ trace_assign_type(field, entry);
+
+ if (!S)
+ task_state_char(field->prev_state);
+ T = task_state_char(field->next_state);
+
+ SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
+ SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
+ SEQ_PUT_HEX_FIELD_RET(s, S);
+ SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
+ SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
+ SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
+ SEQ_PUT_HEX_FIELD_RET(s, T);
+
+ return 0;
+}
+
+static int
+trace_ctx_hex(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ return trace_ctxwake_hex(s, entry, flags, 0);
+}
+
+static int
+trace_wake_hex(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ return trace_ctxwake_hex(s, entry, flags, '+');
+}
+
+static int
+trace_ctxwake_bin(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct ctx_switch_entry *field;
+
+ trace_assign_type(field, entry);
+
+ SEQ_PUT_FIELD_RET(s, field->prev_pid);
+ SEQ_PUT_FIELD_RET(s, field->prev_prio);
+ SEQ_PUT_FIELD_RET(s, field->prev_state);
+ SEQ_PUT_FIELD_RET(s, field->next_pid);
+ SEQ_PUT_FIELD_RET(s, field->next_prio);
+ SEQ_PUT_FIELD_RET(s, field->next_state);
+
+ return 0;
+}
+
+static struct trace_event trace_ctx_event = {
+ .type = TRACE_CTX,
+ .trace = trace_ctx_print,
+ .latency_trace = trace_ctx_print,
+ .raw = trace_ctx_raw,
+ .hex = trace_ctx_hex,
+ .binary = trace_ctxwake_bin,
+};
+
+static struct trace_event trace_wake_event = {
+ .type = TRACE_WAKE,
+ .trace = trace_wake_print,
+ .latency_trace = trace_wake_print,
+ .raw = trace_wake_raw,
+ .hex = trace_wake_hex,
+ .binary = trace_ctxwake_bin,
+};
+
+/* TRACE_SPECIAL */
+static int
+trace_special_print(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct special_entry *field;
+
+ trace_assign_type(field, entry);
+
+ if (trace_seq_printf(s, "# %ld %ld %ld\n",
+ field->arg1,
+ field->arg2,
+ field->arg3))
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return 0;
+}
+
+static int
+trace_special_hex(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct special_entry *field;
+
+ trace_assign_type(field, entry);
+
+ SEQ_PUT_HEX_FIELD_RET(s, field->arg1);
+ SEQ_PUT_HEX_FIELD_RET(s, field->arg2);
+ SEQ_PUT_HEX_FIELD_RET(s, field->arg3);
+
+ return 0;
+}
+
+static int
+trace_special_bin(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct special_entry *field;
+
+ trace_assign_type(field, entry);
+
+ SEQ_PUT_FIELD_RET(s, field->arg1);
+ SEQ_PUT_FIELD_RET(s, field->arg2);
+ SEQ_PUT_FIELD_RET(s, field->arg3);
+
+ return 0;
+}
+
+static struct trace_event trace_special_event = {
+ .type = TRACE_SPECIAL,
+ .trace = trace_special_print,
+ .latency_trace = trace_special_print,
+ .raw = trace_special_print,
+ .hex = trace_special_hex,
+ .binary = trace_special_bin,
+};
+
+/* TRACE_STACK */
+
+static int
+trace_stack_print(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct stack_entry *field;
+ int i;
+
+ trace_assign_type(field, entry);
+
+ for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
+ if (i) {
+ if (trace_seq_puts(s, " <= "))
+ goto partial;
+
+ if (seq_print_ip_sym(s, field->caller[i], flags))
+ goto partial;
+ }
+ if (trace_seq_puts(s, "\n"))
+ goto partial;
+ }
+
+ return 0;
+
+ partial:
+ return TRACE_TYPE_PARTIAL_LINE;
+}
+
+static struct trace_event trace_stack_event = {
+ .type = TRACE_STACK,
+ .trace = trace_stack_print,
+ .latency_trace = trace_stack_print,
+ .raw = trace_special_print,
+ .hex = trace_special_hex,
+ .binary = trace_special_bin,
+};
+
+/* TRACE_USER_STACK */
+static int
+trace_user_stack_print(struct trace_seq *s, struct trace_entry *entry,
+ int flags)
+{
+ struct userstack_entry *field;
+
+ trace_assign_type(field, entry);
+
+ if (seq_print_userip_objs(field, s, flags))
+ goto partial;
+
+ if (trace_seq_putc(s, '\n'))
+ goto partial;
+
+ return 0;
+
+ partial:
+ return TRACE_TYPE_PARTIAL_LINE;
+}
+
+static struct trace_event trace_user_stack_event = {
+ .type = TRACE_USER_STACK,
+ .trace = trace_user_stack_print,
+ .latency_trace = trace_user_stack_print,
+ .raw = trace_special_print,
+ .hex = trace_special_hex,
+ .binary = trace_special_bin,
+};
+
+/* TRACE_PRINT */
+static int
+trace_print_print(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct print_entry *field;
+
+ trace_assign_type(field, entry);
+
+ if (seq_print_ip_sym(s, field->ip, flags))
+ goto partial;
+
+ if (trace_seq_printf(s, ": %s", field->buf))
+ goto partial;
+
+ return 0;
+
+ partial:
+ return TRACE_TYPE_PARTIAL_LINE;
+}
+
+static int
+trace_print_raw(struct trace_seq *s, struct trace_entry *entry, int flags)
+{
+ struct print_entry *field;
+
+ trace_assign_type(field, entry);
+
+ if (seq_print_ip_sym(s, field->ip, flags))
+ goto partial;
+
+ if (trace_seq_printf(s, "# %lx %s", field->ip, field->buf))
+ goto partial;
+
+ return 0;
+
+ partial:
+ return TRACE_TYPE_PARTIAL_LINE;
+}
+
+static struct trace_event trace_print_event = {
+ .type = TRACE_PRINT,
+ .trace = trace_print_print,
+ .latency_trace = trace_print_print,
+ .raw = trace_print_raw,
+ .hex = trace_nop_print,
+ .binary = trace_nop_print,
+};
+
+static struct trace_event *events[] __initdata = {
+ &trace_fn_event,
+ &trace_ctx_event,
+ &trace_wake_event,
+ &trace_special_event,
+ &trace_stack_event,
+ &trace_user_stack_event,
+ &trace_print_event,
+ NULL
+};
+
+__init static int init_events(void)
+{
+ struct trace_event *event;
+ int i, ret;
+
+ for (i = 0; events[i]; i++) {
+ event = events[i];
+
+ ret = register_ftrace_event(event);
+ if (!ret) {
+ printk(KERN_WARNING "event %d failed to register\n",
+ event->type);
+ WARN_ON_ONCE(1);
+ }
+ }
+
+ return 0;
+}
+device_initcall(init_events);
diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h
new file mode 100644
index 00000000000..ecab4ea4a4f
--- /dev/null
+++ b/kernel/trace/trace_output.h
@@ -0,0 +1,59 @@
+#ifndef __TRACE_EVENTS_H
+#define __TRACE_EVENTS_H
+
+#include "trace.h"
+
+typedef int (*trace_print_func)(struct trace_seq *s, struct trace_entry *entry,
+ int flags);
+
+struct trace_event {
+ struct hlist_node node;
+ int type;
+ trace_print_func trace;
+ trace_print_func latency_trace;
+ trace_print_func raw;
+ trace_print_func hex;
+ trace_print_func binary;
+};
+
+extern int trace_seq_printf(struct trace_seq *s, const char *fmt, ...);
+extern int
+seq_print_ip_sym(struct trace_seq *s, unsigned long ip,
+ unsigned long sym_flags);
+extern ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf,
+ size_t cnt);
+int trace_seq_puts(struct trace_seq *s, const char *str);
+int trace_seq_putc(struct trace_seq *s, unsigned char c);
+int trace_seq_putmem(struct trace_seq *s, void *mem, size_t len);
+int trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len);
+int trace_seq_path(struct trace_seq *s, struct path *path);
+int seq_print_userip_objs(const struct userstack_entry *entry,
+ struct trace_seq *s, unsigned long sym_flags);
+int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
+ unsigned long ip, unsigned long sym_flags);
+
+struct trace_event *ftrace_find_event(int type);
+int register_ftrace_event(struct trace_event *event);
+int unregister_ftrace_event(struct trace_event *event);
+
+int
+trace_nop_print(struct trace_seq *s, struct trace_entry *entry, int flags);
+
+#define MAX_MEMHEX_BYTES 8
+#define HEX_CHARS (MAX_MEMHEX_BYTES*2 + 1)
+
+#define SEQ_PUT_FIELD_RET(s, x) \
+do { \
+ if (!trace_seq_putmem(s, &(x), sizeof(x))) \
+ return 0; \
+} while (0)
+
+#define SEQ_PUT_HEX_FIELD_RET(s, x) \
+do { \
+ BUILD_BUG_ON(sizeof(x) > MAX_MEMHEX_BYTES); \
+ if (!trace_seq_putmem_hex(s, &(x), sizeof(x))) \
+ return 0; \
+} while (0)
+
+#endif
+
diff --git a/kernel/trace/trace_power.c b/kernel/trace/trace_power.c
index 7bda248daf5..faa6ab7a1f5 100644
--- a/kernel/trace/trace_power.c
+++ b/kernel/trace/trace_power.c
@@ -16,6 +16,7 @@
#include <linux/module.h>
#include "trace.h"
+#include "trace_output.h"
static struct trace_array *power_trace;
static int __read_mostly trace_power_enabled;
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 88c8eb70f54..5013812578b 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -9,7 +9,6 @@ static inline int trace_valid_entry(struct trace_entry *entry)
case TRACE_FN:
case TRACE_CTX:
case TRACE_WAKE:
- case TRACE_CONT:
case TRACE_STACK:
case TRACE_PRINT:
case TRACE_SPECIAL:
diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c
new file mode 100644
index 00000000000..6f194a33a64
--- /dev/null
+++ b/kernel/trace/trace_stat.c
@@ -0,0 +1,251 @@
+/*
+ * Infrastructure for statistic tracing (histogram output).
+ *
+ * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com>
+ *
+ * Based on the code from trace_branch.c which is
+ * Copyright (C) 2008 Steven Rostedt <srostedt@redhat.com>
+ *
+ */
+
+
+#include <linux/list.h>
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
+#include "trace.h"
+
+
+/* List of stat entries from a tracer */
+struct trace_stat_list {
+ struct list_head list;
+ void *stat;
+};
+
+static struct trace_stat_list stat_list;
+
+/*
+ * This is a copy of the current tracer to avoid racy
+ * and dangerous output while the current tracer is
+ * switched.
+ */
+static struct tracer current_tracer;
+
+/*
+ * Protect both the current tracer and the global
+ * stat list.
+ */
+static DEFINE_MUTEX(stat_list_mutex);
+
+
+static void reset_stat_list(void)
+{
+ struct trace_stat_list *node;
+ struct list_head *next;
+
+ if (list_empty(&stat_list.list))
+ return;
+
+ node = list_entry(stat_list.list.next, struct trace_stat_list, list);
+ next = node->list.next;
+
+ while (&node->list != next) {
+ kfree(node);
+ node = list_entry(next, struct trace_stat_list, list);
+ }
+ kfree(node);
+
+ INIT_LIST_HEAD(&stat_list.list);
+}
+
+void init_tracer_stat(struct tracer *trace)
+{
+ mutex_lock(&stat_list_mutex);
+ current_tracer = *trace;
+ mutex_unlock(&stat_list_mutex);
+}
+
+/*
+ * For tracers that don't provide a stat_cmp callback.
+ * This one will force an immediate insertion on tail of
+ * the list.
+ */
+static int dummy_cmp(void *p1, void *p2)
+{
+ return 1;
+}
+
+/*
+ * Initialize the stat list at each trace_stat file opening.
+ * All of these copies and sorting are required on all opening
+ * since the stats could have changed between two file sessions.
+ */
+static int stat_seq_init(void)
+{
+ struct trace_stat_list *iter_entry, *new_entry;
+ void *prev_stat;
+ int ret = 0;
+ int i;
+
+ mutex_lock(&stat_list_mutex);
+ reset_stat_list();
+
+ if (!current_tracer.stat_start || !current_tracer.stat_next ||
+ !current_tracer.stat_show)
+ goto exit;
+
+ if (!current_tracer.stat_cmp)
+ current_tracer.stat_cmp = dummy_cmp;
+
+ /*
+ * The first entry. Actually this is the second, but the first
+ * one (the stat_list head) is pointless.
+ */
+ new_entry = kmalloc(sizeof(struct trace_stat_list), GFP_KERNEL);
+ if (!new_entry) {
+ ret = -ENOMEM;
+ goto exit;
+ }
+
+ INIT_LIST_HEAD(&new_entry->list);
+ list_add(&new_entry->list, &stat_list.list);
+ new_entry->stat = current_tracer.stat_start();
+
+ prev_stat = new_entry->stat;
+
+ /*
+ * Iterate over the tracer stat entries and store them in a sorted
+ * list.
+ */
+ for (i = 1; ; i++) {
+ new_entry = kmalloc(sizeof(struct trace_stat_list), GFP_KERNEL);
+ if (!new_entry) {
+ ret = -ENOMEM;
+ goto exit_free_list;
+ }
+
+ INIT_LIST_HEAD(&new_entry->list);
+ new_entry->stat = current_tracer.stat_next(prev_stat, i);
+
+ /* End of insertion */
+ if (!new_entry->stat)
+ break;
+
+ list_for_each_entry(iter_entry, &stat_list.list, list) {
+ /* Insertion with a descendent sorting */
+ if (current_tracer.stat_cmp(new_entry->stat,
+ iter_entry->stat) > 0) {
+
+ list_add_tail(&new_entry->list,
+ &iter_entry->list);
+ break;
+
+ /* The current smaller value */
+ } else if (list_is_last(&iter_entry->list,
+ &stat_list.list)) {
+ list_add(&new_entry->list, &iter_entry->list);
+ break;
+ }
+ }
+
+ prev_stat = new_entry->stat;
+ }
+exit:
+ mutex_unlock(&stat_list_mutex);
+ return ret;
+
+exit_free_list:
+ reset_stat_list();
+ mutex_unlock(&stat_list_mutex);
+ return ret;
+}
+
+
+static void *stat_seq_start(struct seq_file *s, loff_t *pos)
+{
+ struct trace_stat_list *l = (struct trace_stat_list *)s->private;
+
+ /* Prevent from tracer switch or stat_list modification */
+ mutex_lock(&stat_list_mutex);
+
+ /* If we are in the beginning of the file, print the headers */
+ if (!*pos && current_tracer.stat_headers)
+ current_tracer.stat_headers(s);
+
+ return seq_list_start(&l->list, *pos);
+}
+
+static void *stat_seq_next(struct seq_file *s, void *p, loff_t *pos)
+{
+ struct trace_stat_list *l = (struct trace_stat_list *)s->private;
+
+ return seq_list_next(p, &l->list, pos);
+}
+
+static void stat_seq_stop(struct seq_file *m, void *p)
+{
+ mutex_unlock(&stat_list_mutex);
+}
+
+static int stat_seq_show(struct seq_file *s, void *v)
+{
+ struct trace_stat_list *l = list_entry(v, struct trace_stat_list, list);
+ return current_tracer.stat_show(s, l->stat);
+}
+
+static const struct seq_operations trace_stat_seq_ops = {
+ .start = stat_seq_start,
+ .next = stat_seq_next,
+ .stop = stat_seq_stop,
+ .show = stat_seq_show
+};
+
+static int tracing_stat_open(struct inode *inode, struct file *file)
+{
+ int ret;
+
+ ret = seq_open(file, &trace_stat_seq_ops);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+ m->private = &stat_list;
+ ret = stat_seq_init();
+ }
+
+ return ret;
+}
+
+
+/*
+ * Avoid consuming memory with our now useless list.
+ */
+static int tracing_stat_release(struct inode *i, struct file *f)
+{
+ mutex_lock(&stat_list_mutex);
+ reset_stat_list();
+ mutex_unlock(&stat_list_mutex);
+ return 0;
+}
+
+static const struct file_operations tracing_stat_fops = {
+ .open = tracing_stat_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = tracing_stat_release
+};
+
+static int __init tracing_stat_init(void)
+{
+ struct dentry *d_tracing;
+ struct dentry *entry;
+
+ INIT_LIST_HEAD(&stat_list.list);
+ d_tracing = tracing_init_dentry();
+
+ entry = debugfs_create_file("trace_stat", 0444, d_tracing,
+ NULL,
+ &tracing_stat_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs "
+ "'trace_stat' entry\n");
+ return 0;
+}
+fs_initcall(tracing_stat_init);