offcputime: add the -d option

Closes #559

tools/offcputime.py

@@ -61,6 +61,8 @@ def positive_nonzero_int(val):
  help="show stacks from user space only (no kernel space stacks)")
 stack_group.add_argument("-K", "--kernel-stacks-only", action="store_true",
  help="show stacks from kernel space only (no user space stacks)")
+parser.add_argument("-d", "--delimited", action="store_true",
+ help="insert delimiter between kernel/user stacks")
 parser.add_argument("-f", "--folded", action="store_true",
  help="output folded format")
 parser.add_argument("--stack-storage-size", default=1024,
@@ -170,6 +172,8 @@ def signal_ignore(signal, frame):
 bpf_text = bpf_text.replace('USER_STACK_GET', user_stack_get)
 bpf_text = bpf_text.replace('KERNEL_STACK_GET', kernel_stack_get)
 
+need_delimiter = args.delimited and not (args.kernel_stacks_only or args.user_stacks_only)
+
 # check for an edge case; the code below will handle this case correctly
 # but ultimately nothing will be displayed
 if args.kernel_threads_only and args.user_stacks_only:
@@ -229,12 +233,15 @@ def signal_ignore(signal, frame):
  kernel_stack = list(kernel_stack)
  line = [k.name.decode()] + \
  [b.sym(addr, k.pid) for addr in reversed(user_stack)] + \
+ (need_delimiter and ["-"] or []) + \
  [b.ksym(addr) for addr in reversed(kernel_stack)]
  print("%s %d" % (";".join(line), v.value))
  else:
  # print default multi-line stack output
  for addr in kernel_stack:
  print(" %016x %s" % (addr, b.ksym(addr)))
+ if need_delimiter:
+ print(" --")
  for addr in user_stack:
  print(" %016x %s" % (addr, b.sym(addr, k.pid)))
  print(" %-16s %s (%d)" % ("-", k.name, k.pid))