added spaces and tidyup of biosnoop

tools/biosnoop.py

@@ -13,7 +13,6 @@
 # 16-Sep-2015 Brendan Gregg Created this.
 # 11-Feb-2016 Allan McAleavy updated for BPF_PERF_OUTPUT
 
-
 from __future__ import print_function
 from bcc import BPF
 import ctypes as ct
@@ -40,7 +39,6 @@
  char name[TASK_COMM_LEN];
 };
 
-
 BPF_HASH(start, struct request *);
 BPF_HASH(infobyreq, struct request *, struct val_t);
 BPF_PERF_OUTPUT(events);
@@ -118,7 +116,6 @@
 b.attach_kprobe(event="blk_account_io_completion",
  fn_name="trace_req_completion")
 
-
 TASK_COMM_LEN = 16 # linux/sched.h
 DISK_NAME_LEN = 32 # linux/genhd.h
 
@@ -144,25 +141,34 @@ class Data(ct.Structure):
 # process event
 def print_event(cpu, data, size):
  event = ct.cast(data, ct.POINTER(Data)).contents
+
  val = -1
  global start_ts
  global prev_ts
  global delta
+
  if event.rwflag == 1:
  rwflg = "W"
+
  if event.rwflag == 0:
  rwflg = "R"
+
  if not re.match('\?', event.name):
  val = event.sector
+
  if start_ts == 0:
  prev_ts = start_ts
+
  if start_ts == 1:
  delta = float(delta) + (event.ts - prev_ts)
+
  print("%-14.9f %-14.14s %-6s %-7s %-2s %-9s %-7s %7.2f" % (
  delta / 1000000, event.name, event.pid, event.disk_name, rwflg, val,
  event.len, float(event.delta) / 1000000))
+
  prev_ts = event.ts
  start_ts = 1
+
 b["events"].open_perf_buffer(print_event)
 while 1:
  b.kprobe_poll()