*  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,
        TRACE_FLAG_NEED_RESCHED         = 0x02,
        TRACE_FLAG_HARDIRQ              = 0x04,
        TRACE_FLAG_SOFTIRQ              = 0x08,
+       TRACE_FLAG_CONT                 = 0x10,
 };
 
 /*
        TRACE_FILE_LAT_FMT      = 1,
 };
 
+/* Return the current entry.  */
 static struct trace_entry *
 trace_entry_idx(struct trace_array *tr, struct trace_array_cpu *data,
                struct trace_iterator *iter, int cpu)
        return &array[iter->next_page_idx[cpu]];
 }
 
+/* Increment the index counter of an iterator by one */
+static void trace_iterator_increment(struct trace_iterator *iter, int cpu)
+{
+       iter->idx++;
+       iter->next_idx[cpu]++;
+       iter->next_page_idx[cpu]++;
+
+       if (iter->next_page_idx[cpu] >= ENTRIES_PER_PAGE) {
+               struct trace_array_cpu *data = iter->tr->data[cpu];
+
+               iter->next_page_idx[cpu] = 0;
+               iter->next_page[cpu] =
+                       trace_next_list(data, iter->next_page[cpu]);
+       }
+}
+
 static struct trace_entry *
-find_next_entry(struct trace_iterator *iter, int *ent_cpu)
+trace_entry_next(struct trace_array *tr, struct trace_array_cpu *data,
+                struct trace_iterator *iter, int cpu)
+{
+       struct list_head *next_page;
+       struct trace_entry *ent;
+       int idx, next_idx, next_page_idx;
+
+       ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu);
+
+       if (likely(!ent || ent->type != TRACE_CONT))
+               return ent;
+
+       /* save the iterator details */
+       idx             = iter->idx;
+       next_idx        = iter->next_idx[cpu];
+       next_page_idx   = iter->next_page_idx[cpu];
+       next_page       = iter->next_page[cpu];
+
+       /* find a real entry */
+       do {
+               trace_iterator_increment(iter, cpu);
+               ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu);
+       } while (ent && ent->type != TRACE_CONT);
+
+       /* reset the iterator */
+       iter->idx                       = idx;
+       iter->next_idx[cpu]             = next_idx;
+       iter->next_page_idx[cpu]        = next_page_idx;
+       iter->next_page[cpu]            = next_page;
+
+       return ent;
+}
+
+static struct trace_entry *
+__find_next_entry(struct trace_iterator *iter, int *ent_cpu, int inc)
 {
        struct trace_array *tr = iter->tr;
        struct trace_entry *ent, *next = NULL;
        for_each_tracing_cpu(cpu) {
                if (!head_page(tr->data[cpu]))
                        continue;
+
                ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu);
+
+               if (ent && ent->type == TRACE_CONT) {
+                       struct trace_array_cpu *data = tr->data[cpu];
+
+                       if (!inc)
+                               ent = trace_entry_next(tr, data, iter, cpu);
+                       else {
+                               while (ent && ent->type == TRACE_CONT) {
+                                       trace_iterator_increment(iter, cpu);
+                                       ent = trace_entry_idx(tr, tr->data[cpu],
+                                                             iter, cpu);
+                               }
+                       }
+               }
+
                /*
                 * Pick the entry with the smallest timestamp:
                 */
        return next;
 }
 
-static void trace_iterator_increment(struct trace_iterator *iter)
+/* Find the next real entry, without updating the iterator itself */
+static struct trace_entry *
+find_next_entry(struct trace_iterator *iter, int *ent_cpu)
 {
-       iter->idx++;
-       iter->next_idx[iter->cpu]++;
-       iter->next_page_idx[iter->cpu]++;
+       return __find_next_entry(iter, ent_cpu, 0);
+}
+
+/* Find the next real entry, and increment the iterator to the next entry */
+static void *find_next_entry_inc(struct trace_iterator *iter)
+{
+       struct trace_entry *next;
+       int next_cpu = -1;
 
-       if (iter->next_page_idx[iter->cpu] >= ENTRIES_PER_PAGE) {
-               struct trace_array_cpu *data = iter->tr->data[iter->cpu];
+       next = __find_next_entry(iter, &next_cpu, 1);
 
-               iter->next_page_idx[iter->cpu] = 0;
-               iter->next_page[iter->cpu] =
-                       trace_next_list(data, iter->next_page[iter->cpu]);
-       }
+       iter->prev_ent = iter->ent;
+       iter->prev_cpu = iter->cpu;
+
+       iter->ent = next;
+       iter->cpu = next_cpu;
+
+       if (next)
+               trace_iterator_increment(iter, iter->cpu);
+
+       return next ? iter : NULL;
 }
 
 static void trace_consume(struct trace_iterator *iter)
 {
        struct trace_array_cpu *data = iter->tr->data[iter->cpu];
+       struct trace_entry *ent;
 
+ again:
        data->trace_tail_idx++;
        if (data->trace_tail_idx >= ENTRIES_PER_PAGE) {
                data->trace_tail = trace_next_page(data, data->trace_tail);
        if (data->trace_head == data->trace_tail &&
            data->trace_head_idx == data->trace_tail_idx)
                data->trace_idx = 0;
-}
-
-static void *find_next_entry_inc(struct trace_iterator *iter)
-{
-       struct trace_entry *next;
-       int next_cpu = -1;
-
-       next = find_next_entry(iter, &next_cpu);
-
-       iter->prev_ent = iter->ent;
-       iter->prev_cpu = iter->cpu;
-
-       iter->ent = next;
-       iter->cpu = next_cpu;
-
-       if (next)
-               trace_iterator_increment(iter);
 
-       return next ? iter : NULL;
+       ent = trace_entry_idx(iter->tr, iter->tr->data[iter->cpu],
+                             iter, iter->cpu);
+       if (ent && ent->type == TRACE_CONT)
+               goto again;
 }
 
 static void *s_next(struct seq_file *m, void *v, loff_t *pos)
 
 static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
 
+static void
+trace_seq_print_cont(struct trace_seq *s, struct trace_iterator *iter)
+{
+       struct trace_array *tr = iter->tr;
+       struct trace_array_cpu *data = tr->data[iter->cpu];
+       struct trace_entry *ent;
+
+       ent = trace_entry_idx(tr, data, iter, iter->cpu);
+       if (!ent || ent->type != TRACE_CONT) {
+               trace_seq_putc(s, '\n');
+               return;
+       }
+
+       do {
+               trace_seq_printf(s, "%s", ent->cont.buf);
+               trace_iterator_increment(iter, iter->cpu);
+               ent = trace_entry_idx(tr, data, iter, iter->cpu);
+       } while (ent && ent->type == TRACE_CONT);
+}
+
 static int
 print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu)
 {
 
        if (!next_entry)
                next_entry = entry;
+
+       if (entry->type == TRACE_CONT)
+               return 1;
+
        rel_usecs = ns2usecs(next_entry->field.t - entry->field.t);
        abs_usecs = ns2usecs(entry->field.t - iter->tr->time_start);
 
                }
                trace_seq_puts(s, "\n");
                break;
+       case TRACE_PRINT:
+               seq_print_ip_sym(s, field->print.ip, sym_flags);
+               trace_seq_printf(s, ": %s", field->print.buf);
+               if (field->flags && TRACE_FLAG_CONT)
+                       trace_seq_print_cont(s, iter);
+               break;
        default:
                trace_seq_printf(s, "Unknown type %d\n", entry->type);
        }
        int i;
 
        entry = iter->ent;
+
+       if (entry->type == TRACE_CONT)
+               return 1;
+
        field = &entry->field;
 
        comm = trace_find_cmdline(iter->ent->field.pid);
                if (!ret)
                        return 0;
                break;
+       case TRACE_PRINT:
+               seq_print_ip_sym(s, field->print.ip, sym_flags);
+               trace_seq_printf(s, ": %s", field->print.buf);
+               if (field->flags && TRACE_FLAG_CONT)
+                       trace_seq_print_cont(s, iter);
+               break;
        }
        return 1;
 }
        int S, T;
 
        entry = iter->ent;
+
+       if (entry->type == TRACE_CONT)
+               return 1;
+
        field = &entry->field;
 
        ret = trace_seq_printf(s, "%d %d %llu ",
                if (!ret)
                        return 0;
                break;
+       case TRACE_PRINT:
+               trace_seq_printf(s, "# %lx %s",
+                                field->print.ip, field->print.buf);
+               if (field->flags && TRACE_FLAG_CONT)
+                       trace_seq_print_cont(s, iter);
+               break;
        }
        return 1;
 }
        int S, T;
 
        entry = iter->ent;
+
+       if (entry->type == TRACE_CONT)
+               return 1;
+
        field = &entry->field;
 
        SEQ_PUT_HEX_FIELD_RET(s, field->pid);
        struct trace_field *field;
 
        entry = iter->ent;
+
+       if (entry->type == TRACE_CONT)
+               return 1;
+
        field = &entry->field;
 
        SEQ_PUT_FIELD_RET(s, field->pid);
 #endif
 }
 
+#define TRACE_BUF_SIZE 1024
+#define TRACE_PRINT_BUF_SIZE \
+       (sizeof(struct trace_field) - offsetof(struct trace_field, print.buf))
+#define TRACE_CONT_BUF_SIZE sizeof(struct trace_field)
+
+/**
+ * ftrace_printk - printf formatting in the ftrace buffer
+ * @fmt - the printf format for printing.
+ *
+ * Note: __ftrace_printk is an internal function for ftrace_printk and
+ *       the @ip is passed in via the ftrace_printk macro.
+ *
+ * This function allows a kernel developer to debug fast path sections
+ * that printk is not appropriate for. By scattering in various
+ * printk like tracing in the code, a developer can quickly see
+ * where problems are occurring.
+ *
+ * This is intended as a debugging tool for the developer only.
+ * Please reframe from leaving ftrace_printks scattered around in
+ * your code.
+ */
+int __ftrace_printk(unsigned long ip, const char *fmt, ...)
+{
+       struct trace_array *tr = &global_trace;
+       static DEFINE_SPINLOCK(trace_buf_lock);
+       static char trace_buf[TRACE_BUF_SIZE];
+       struct trace_array_cpu *data;
+       struct trace_entry *entry;
+       unsigned long flags;
+       long disabled;
+       va_list ap;
+       int cpu, len = 0, write, written = 0;
+
+       if (likely(!ftrace_function_enabled))
+               return 0;
+
+       local_irq_save(flags);
+       cpu = raw_smp_processor_id();
+       data = tr->data[cpu];
+       disabled = atomic_inc_return(&data->disabled);
+
+       if (unlikely(disabled != 1 || !ftrace_function_enabled))
+               goto out;
+
+       spin_lock(&trace_buf_lock);
+       va_start(ap, fmt);
+       len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, ap);
+       va_end(ap);
+
+       len = min(len, TRACE_BUF_SIZE-1);
+       trace_buf[len] = 0;
+
+       __raw_spin_lock(&data->lock);
+       entry                           = tracing_get_trace_entry(tr, data);
+       tracing_generic_entry_update(entry, flags);
+       entry->type                     = TRACE_PRINT;
+       entry->field.print.ip           = ip;
+
+       write = min(len, (int)(TRACE_PRINT_BUF_SIZE-1));
+
+       memcpy(&entry->field.print.buf, trace_buf, write);
+       entry->field.print.buf[write] = 0;
+       written = write;
+
+       if (written != len)
+               entry->field.flags |= TRACE_FLAG_CONT;
+
+       while (written != len) {
+               entry = tracing_get_trace_entry(tr, data);
+
+               entry->type = TRACE_CONT;
+               write = min(len - written, (int)(TRACE_CONT_BUF_SIZE-1));
+               memcpy(&entry->cont.buf, trace_buf+written, write);
+               entry->cont.buf[write] = 0;
+               written += write;
+       }
+       __raw_spin_unlock(&data->lock);
+
+       spin_unlock(&trace_buf_lock);
+
+ out:
+       atomic_dec(&data->disabled);
+       local_irq_restore(flags);
+
+       return len;
+}
+EXPORT_SYMBOL_GPL(__ftrace_printk);
+
 static int trace_alloc_page(void)
 {
        struct trace_array_cpu *data;