vlib: stack trace and signal handler improvements

 - use libunwrap which seems to be industry standard
 - display traceback on console if running interactive or with syslog
   disabled (color output unless nocolor specified)
 - print hexdump of offending code
 - print library filename for each stack frame

Type: improvement
Change-Id: I61d3056251b87076be0578ccda300aa311c222ef
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 17 insertions, 8 deletions

diff --git a/src/vppinfra/mem_dlmalloc.c b/src/vppinfra/mem_dlmalloc.c
index a188164a7ba..e98687fff2a 100644
--- a/src/vppinfra/mem_dlmalloc.c
+++ b/src/vppinfra/mem_dlmalloc.c
@@ -19,6 +19,7 @@
 #include <vppinfra/lock.h>
 #include <vppinfra/hash.h>
 #include <vppinfra/elf_clib.h>
+#include <vppinfra/stack.h>
 
 typedef struct
 {
@@ -65,15 +66,13 @@ mheap_get_trace_internal (const clib_mem_heap_t *heap, uword offset,
 {
   mheap_trace_main_t *tm = &mheap_trace_main;
   mheap_trace_t *t;
-  uword i, n_callers, trace_index, *p;
-  mheap_trace_t trace;
+  uword i, trace_index, *p;
+  mheap_trace_t trace = {};
+  int index;
 
   if (heap != tm->current_traced_mheap || mheap_trace_thread_disable)
     return;
 
-  /* Spurious Coverity warnings be gone. */
-  clib_memset (&trace, 0, sizeof (trace));
-
   clib_spinlock_lock (&tm->lock);
 
   /* heap could have changed while we were waiting on the lock */
@@ -83,9 +82,19 @@ mheap_get_trace_internal (const clib_mem_heap_t *heap, uword offset,
   /* Turn off tracing for this thread to avoid embarrassment... */
   mheap_trace_thread_disable = 1;
 
-  /* Skip our frame and mspace_get_aligned's frame */
-  n_callers = clib_backtrace (trace.callers, ARRAY_LEN (trace.callers), 2);
-  if (n_callers == 0)
+  index = -2; /* skip first 2 stack frames */
+  foreach_clib_stack_frame (sf)
+    {
+      if (index >= 0)
+	{
+	  if (index == ARRAY_LEN (trace.callers))
+	    break;
+	  trace.callers[index] = sf->ip;
+	}
+      index++;
+    }
+
+  if (index < 1)
     goto out;
 
   if (!tm->trace_by_callers)