mmiotrace: handle TRACE_PRINT entries

Also make trace_seq_print_cont() non-static, and add a newline if the
seq buffer can't hold all data.

Signed-off-by: Pekka Paalanen <pq@iki.fi>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 11 insertions, 20 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 406de9cf2820..7e7154f77009 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -200,23 +200,6 @@ unsigned long nsecs_to_usecs(unsigned long nsecs)
 }
 
 /*
- * trace_flag_type is an enumeration that holds different
- * states when a trace occurs. These are:
- *  IRQS_OFF    - interrupts were disabled
- *  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_ITER_SYM_MASK masks the options in trace_flags that
  * control the output of kernel symbols.
  */
@@ -1517,12 +1500,16 @@ lat_print_timestamp(struct trace_seq *s, unsigned long long abs_usecs,
 
 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)
+/*
+ * 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_array *tr = iter->tr;
         struct trace_array_cpu *data = tr->data[iter->cpu];
         struct trace_entry *ent;
+        bool ok = true;
 
         ent = trace_entry_idx(tr, data, iter, iter->cpu);
         if (!ent || ent->type != TRACE_CONT) {
@@ -1531,10 +1518,14 @@ trace_seq_print_cont(struct trace_seq *s, struct trace_iterator *iter)
         }
 
         do {
-                trace_seq_printf(s, "%s", ent->cont.buf);
+                if (ok)
+                        ok = (trace_seq_printf(s, "%s", ent->cont.buf) > 0);
                 __trace_iterator_increment(iter, iter->cpu);
                 ent = trace_entry_idx(tr, data, iter, iter->cpu);
         } while (ent && ent->type == TRACE_CONT);
+
+        if (!ok)
+                trace_seq_putc(s, '\n');
 }
 
 static int