/* must be a power of 2 */
#define EVENT_HASHSIZE 128
-static DEFINE_MUTEX(trace_event_mutex);
+DECLARE_RWSEM(trace_event_mutex);
+
+DEFINE_PER_CPU(struct trace_seq, ftrace_event_seq);
+EXPORT_PER_CPU_SYMBOL(ftrace_event_seq);
+
static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
static int next_event_type = __TRACE_LAST_TYPE + 1;
+int trace_print_seq(struct seq_file *m, struct trace_seq *s)
+{
+ int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
+ int ret;
+
+ ret = seq_write(m, s->buffer, len);
+
+ /*
+ * Only reset this buffer if we successfully wrote to the
+ * seq_file buffer.
+ */
+ if (!ret)
+ trace_seq_init(s);
+
+ return ret;
+}
+
enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
{
struct trace_seq *s = &iter->seq;
* @s: trace sequence descriptor
* @fmt: printf format string
*
+ * It returns 0 if the trace oversizes the buffer's free
+ * space, 1 otherwise.
+ *
* 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
va_list ap;
int ret;
- if (!len)
+ if (s->full || !len)
return 0;
va_start(ap, fmt);
va_end(ap);
/* If we can't write it all, don't bother writing anything */
- if (ret >= len)
+ if (ret >= len) {
+ s->full = 1;
return 0;
+ }
+
+ s->len += ret;
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(trace_seq_printf);
+
+/**
+ * trace_seq_vprintf - 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_vprintf(struct trace_seq *s, const char *fmt, va_list args)
+{
+ int len = (PAGE_SIZE - 1) - s->len;
+ int ret;
+
+ if (s->full || !len)
+ return 0;
+
+ ret = vsnprintf(s->buffer + s->len, len, fmt, args);
+
+ /* If we can't write it all, don't bother writing anything */
+ if (ret >= len) {
+ s->full = 1;
+ return 0;
+ }
s->len += ret;
return len;
}
+EXPORT_SYMBOL_GPL(trace_seq_vprintf);
int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
{
int len = (PAGE_SIZE - 1) - s->len;
int ret;
- if (!len)
+ if (s->full || !len)
return 0;
ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
/* If we can't write it all, don't bother writing anything */
- if (ret >= len)
+ if (ret >= len) {
+ s->full = 1;
return 0;
+ }
s->len += ret;
{
int len = strlen(str);
- if (len > ((PAGE_SIZE - 1) - s->len))
+ if (s->full)
return 0;
+ if (len > ((PAGE_SIZE - 1) - s->len)) {
+ s->full = 1;
+ return 0;
+ }
+
memcpy(s->buffer + s->len, str, len);
s->len += len;
int trace_seq_putc(struct trace_seq *s, unsigned char c)
{
- if (s->len >= (PAGE_SIZE - 1))
+ if (s->full)
+ return 0;
+
+ if (s->len >= (PAGE_SIZE - 1)) {
+ s->full = 1;
return 0;
+ }
s->buffer[s->len++] = c;
return 1;
}
-int trace_seq_putmem(struct trace_seq *s, void *mem, size_t len)
+int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
{
- if (len > ((PAGE_SIZE - 1) - s->len))
+ if (s->full)
return 0;
+ if (len > ((PAGE_SIZE - 1) - s->len)) {
+ s->full = 1;
+ 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)
+int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
{
unsigned char hex[HEX_CHARS];
- unsigned char *data = mem;
+ const unsigned char *data = mem;
int i, j;
+ if (s->full)
+ return 0;
+
#ifdef __BIG_ENDIAN
for (i = 0, j = 0; i < len; i++) {
#else
return trace_seq_putmem(s, hex, j);
}
+void *trace_seq_reserve(struct trace_seq *s, size_t len)
+{
+ void *ret;
+
+ if (s->full)
+ return 0;
+
+ if (len > ((PAGE_SIZE - 1) - s->len)) {
+ s->full = 1;
+ return NULL;
+ }
+
+ ret = s->buffer + s->len;
+ s->len += len;
+
+ return ret;
+}
+
int trace_seq_path(struct trace_seq *s, struct path *path)
{
unsigned char *p;
- if (s->len >= (PAGE_SIZE - 1))
+ if (s->full)
+ return 0;
+
+ if (s->len >= (PAGE_SIZE - 1)) {
+ s->full = 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");
return 1;
}
+ s->full = 1;
return 0;
}
+const char *
+ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
+ unsigned long flags,
+ const struct trace_print_flags *flag_array)
+{
+ unsigned long mask;
+ const char *str;
+ const char *ret = p->buffer + p->len;
+ int i;
+
+ for (i = 0; flag_array[i].name && flags; i++) {
+
+ mask = flag_array[i].mask;
+ if ((flags & mask) != mask)
+ continue;
+
+ str = flag_array[i].name;
+ flags &= ~mask;
+ if (p->len && delim)
+ trace_seq_puts(p, delim);
+ trace_seq_puts(p, str);
+ }
+
+ /* check for left over flags */
+ if (flags) {
+ if (p->len && delim)
+ trace_seq_puts(p, delim);
+ trace_seq_printf(p, "0x%lx", flags);
+ }
+
+ trace_seq_putc(p, 0);
+
+ return ret;
+}
+EXPORT_SYMBOL(ftrace_print_flags_seq);
+
+const char *
+ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
+ const struct trace_print_flags *symbol_array)
+{
+ int i;
+ const char *ret = p->buffer + p->len;
+
+ for (i = 0; symbol_array[i].name; i++) {
+
+ if (val != symbol_array[i].mask)
+ continue;
+
+ trace_seq_puts(p, symbol_array[i].name);
+ break;
+ }
+
+ if (!p->len)
+ trace_seq_printf(p, "0x%lx", val);
+
+ trace_seq_putc(p, 0);
+
+ return ret;
+}
+EXPORT_SYMBOL(ftrace_print_symbols_seq);
+
#ifdef CONFIG_KRETPROBES
static inline const char *kretprobed(const char *name)
{
unsigned long vmstart = 0;
int ret = 1;
+ if (s->full)
+ return 0;
+
if (mm) {
const struct vm_area_struct *vma;
* since individual threads might have already quit!
*/
rcu_read_lock();
- task = find_task_by_vpid(entry->ent.tgid);
+ task = find_task_by_vpid(entry->tgid);
if (task)
mm = get_task_mm(task);
rcu_read_unlock();
if (ip == ULONG_MAX || !ret)
break;
- if (i && ret)
- ret = trace_seq_puts(s, " <- ");
+ if (ret)
+ ret = trace_seq_puts(s, " => ");
if (!ip) {
if (ret)
ret = trace_seq_puts(s, "??");
+ if (ret)
+ ret = trace_seq_puts(s, "\n");
continue;
}
if (!ret)
break;
if (ret)
ret = seq_print_user_ip(s, mm, ip, sym_flags);
+ ret = trace_seq_puts(s, "\n");
}
if (mm)
return ret;
}
-static int
-lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
+/**
+ * trace_print_lat_fmt - print the irq, preempt and lockdep fields
+ * @s: trace seq struct to write to
+ * @entry: The trace entry field from the ring buffer
+ *
+ * Prints the generic fields of irqs off, in hard or softirq, preempt
+ * count and lock depth.
+ */
+int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
{
int hardirq, softirq;
- char comm[TASK_COMM_LEN];
+ int ret;
- trace_find_cmdline(entry->pid, comm);
hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
- if (!trace_seq_printf(s, "%8.8s-%-5d %3d%c%c%c",
- comm, entry->pid, cpu,
+ if (!trace_seq_printf(s, "%c%c%c",
(entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ?
'X' : '.',
return 0;
if (entry->preempt_count)
- return trace_seq_printf(s, "%x", entry->preempt_count);
- return trace_seq_puts(s, ".");
+ ret = trace_seq_printf(s, "%x", entry->preempt_count);
+ else
+ ret = trace_seq_putc(s, '.');
+
+ if (!ret)
+ return 0;
+
+ if (entry->lock_depth < 0)
+ return trace_seq_putc(s, '.');
+
+ return trace_seq_printf(s, "%d", entry->lock_depth);
+}
+
+static int
+lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
+{
+ char comm[TASK_COMM_LEN];
+
+ trace_find_cmdline(entry->pid, comm);
+
+ if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
+ comm, entry->pid, cpu))
+ return 0;
+
+ return trace_print_lat_fmt(s, entry);
}
static unsigned long preempt_mark_thresh = 100;
trace_find_cmdline(entry->pid, comm);
- ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08lx]"
+ ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]"
" %ld.%03ldms (+%ld.%03ldms): ", comm,
entry->pid, iter->cpu, entry->flags,
entry->preempt_count, iter->idx,
* @type: the type of event to look for
*
* Returns an event of type @type otherwise NULL
+ * Called with trace_event_read_lock() held.
*/
struct trace_event *ftrace_find_event(int type)
{
key = type & (EVENT_HASHSIZE - 1);
- hlist_for_each_entry_rcu(event, n, &event_hash[key], node) {
+ hlist_for_each_entry(event, n, &event_hash[key], node) {
if (event->type == type)
return event;
}
return NULL;
}
+static LIST_HEAD(ftrace_event_list);
+
+static int trace_search_list(struct list_head **list)
+{
+ struct trace_event *e;
+ int last = __TRACE_LAST_TYPE;
+
+ if (list_empty(&ftrace_event_list)) {
+ *list = &ftrace_event_list;
+ return last + 1;
+ }
+
+ /*
+ * We used up all possible max events,
+ * lets see if somebody freed one.
+ */
+ list_for_each_entry(e, &ftrace_event_list, list) {
+ if (e->type != last + 1)
+ break;
+ last++;
+ }
+
+ /* Did we used up all 65 thousand events??? */
+ if ((last + 1) > FTRACE_MAX_EVENT)
+ return 0;
+
+ *list = &e->list;
+ return last + 1;
+}
+
+void trace_event_read_lock(void)
+{
+ down_read(&trace_event_mutex);
+}
+
+void trace_event_read_unlock(void)
+{
+ up_read(&trace_event_mutex);
+}
+
/**
* register_ftrace_event - register output for an event type
* @event: the event type to register
unsigned key;
int ret = 0;
- mutex_lock(&trace_event_mutex);
+ down_write(&trace_event_mutex);
+
+ if (WARN_ON(!event))
+ goto out;
+
+ INIT_LIST_HEAD(&event->list);
+
+ if (!event->type) {
+ struct list_head *list = NULL;
+
+ if (next_event_type > FTRACE_MAX_EVENT) {
+
+ event->type = trace_search_list(&list);
+ if (!event->type)
+ goto out;
+
+ } else {
+
+ event->type = next_event_type++;
+ list = &ftrace_event_list;
+ }
+
+ if (WARN_ON(ftrace_find_event(event->type)))
+ goto out;
+
+ list_add_tail(&event->list, list);
- if (!event->type)
- event->type = next_event_type++;
- else if (event->type > __TRACE_LAST_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;
+ } else {
+ /* Is this event already used */
+ if (ftrace_find_event(event->type))
+ goto out;
+ }
if (event->trace == NULL)
event->trace = trace_nop_print;
key = event->type & (EVENT_HASHSIZE - 1);
- hlist_add_head_rcu(&event->node, &event_hash[key]);
+ hlist_add_head(&event->node, &event_hash[key]);
ret = event->type;
out:
- mutex_unlock(&trace_event_mutex);
+ up_write(&trace_event_mutex);
return ret;
}
+EXPORT_SYMBOL_GPL(register_ftrace_event);
+
+/*
+ * Used by module code with the trace_event_mutex held for write.
+ */
+int __unregister_ftrace_event(struct trace_event *event)
+{
+ hlist_del(&event->node);
+ list_del(&event->list);
+ return 0;
+}
/**
* unregister_ftrace_event - remove a no longer used event
*/
int unregister_ftrace_event(struct trace_event *event)
{
- mutex_lock(&trace_event_mutex);
- hlist_del(&event->node);
- mutex_unlock(&trace_event_mutex);
+ down_write(&trace_event_mutex);
+ __unregister_ftrace_event(event);
+ up_write(&trace_event_mutex);
return 0;
}
+EXPORT_SYMBOL_GPL(unregister_ftrace_event);
/*
* Standard events
trace_assign_type(field, iter->ent);
if (!S)
- task_state_char(field->prev_state);
+ S = task_state_char(field->prev_state);
T = task_state_char(field->next_state);
if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
field->prev_pid,
trace_assign_type(field, iter->ent);
if (!S)
- task_state_char(field->prev_state);
+ S = task_state_char(field->prev_state);
T = task_state_char(field->next_state);
SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
trace_assign_type(field, iter->ent);
+ if (!trace_seq_puts(s, "<stack trace>\n"))
+ goto partial;
for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
- if (i) {
- if (!trace_seq_puts(s, " <= "))
- goto partial;
+ if (!field->caller[i] || (field->caller[i] == ULONG_MAX))
+ break;
+ if (!trace_seq_puts(s, " => "))
+ goto partial;
- if (!seq_print_ip_sym(s, field->caller[i], flags))
- goto partial;
- }
+ if (!seq_print_ip_sym(s, field->caller[i], flags))
+ goto partial;
if (!trace_seq_puts(s, "\n"))
goto partial;
}
trace_assign_type(field, iter->ent);
- if (!seq_print_userip_objs(field, s, flags))
+ if (!trace_seq_puts(s, "<user stack trace>\n"))
goto partial;
- if (!trace_seq_putc(s, '\n'))
+ if (!seq_print_userip_objs(field, s, flags))
goto partial;
return TRACE_TYPE_HANDLED;