add --state to offcputime

man/man8/offcputime.8

@@ -2,7 +2,7 @@
 .SH NAME
 offcputime \- Summarize off-CPU time by kernel stack trace. Uses Linux eBPF/bcc.
 .SH SYNOPSIS
-.B offcputime [\-h] [\-u] [\-p PID] [\-v] [\-f] [duration]
+.B offcputime [\-h] [\-p PID | \-t TID | \-u | \-k] [\-U | \-K] [\-d] [\-f] [\-\-stack\-storage\-size STACK_STORAGE_SIZE] [\-m MIN_BLOCK_TIME] [\-M MAX_BLOCK_TIME] [\-\-state STATE] [duration]
 .SH DESCRIPTION
 This program shows stack traces and task names that were blocked and "off-CPU",
 and the total duration they were not running: their "off-CPU time".
@@ -64,6 +64,16 @@ Output folded format.
 \-\-stack-storage-size STACK_STORAGE_SIZE
 Change the number of unique stack traces that can be stored and displayed.
 .TP
+\-m MIN_BLOCK_TIME
+The minimum time in microseconds over which we store traces (default 1)
+.TP
+\-M MAX_BLOCK_TIME
+The maximum time in microseconds under which we store traces (default U64_MAX)
+.TP
+\-\-state
+Filter on this thread state bitmask (eg, 2 == TASK_UNINTERRUPTIBLE).
+See include/linux/sched.h for states.
+.TP
 duration
 Duration to trace, in seconds.
 .SH EXAMPLES

tools/offcputime.py

@@ -88,11 +88,16 @@ def positive_nonzero_int(val):
  type=positive_nonzero_int,
  help="the amount of time in microseconds under which we " +
  "store traces (default U64_MAX)")
+parser.add_argument("--state", default=999,
+ type=positive_int,
+ help="filter on this thread state bitmask (eg, 2 == TASK_UNINTERRUPTIBLE" +
+ ") see include/linux/sched.h")
 args = parser.parse_args()
 if args.pid and args.tgid:
  parser.error("specify only one of -p and -t")
 folded = args.folded
 duration = int(args.duration)
+debug = 0
 
 # signal handler
 def signal_ignore(signal, frame):
@@ -123,7 +128,7 @@ def signal_ignore(signal, frame):
  u64 ts, *tsp;
 
  // record previous thread sleep time
- if (THREAD_FILTER) {
+ if ((THREAD_FILTER) && (STATE_FILTER)) {
  ts = bpf_ktime_get_ns();
  start.update(&pid, &ts);
  }
@@ -177,7 +182,15 @@ def signal_ignore(signal, frame):
 else:
  thread_context = "all threads"
  thread_filter = '1'
+if args.state == 0:
+ state_filter = 'prev->state == 0'
+elif args.state != 999:
+ # these states are sometimes bitmask checked
+ state_filter = 'prev->state & %d' % args.state
+else:
+ state_filter = '1'
 bpf_text = bpf_text.replace('THREAD_FILTER', thread_filter)
+bpf_text = bpf_text.replace('STATE_FILTER', state_filter)
 
 # set stack storage size
 bpf_text = bpf_text.replace('STACK_STORAGE_SIZE', str(args.stack_storage_size))
@@ -210,6 +223,9 @@ def signal_ignore(signal, frame):
  "doesn't make sense.", file=stderr)
  exit(1)
 
+if (debug):
+ print(bpf_text)
+
 # initialize BPF
 b = BPF(text=bpf_text)
 b.attach_kprobe(event="finish_task_switch", fn_name="oncpu")

tools/offcputime_example.txt

@@ -718,9 +718,10 @@ creating your "off-CPU time flame graphs".
 
 USAGE message:
 
-# ./offcputime -h
+# ./offcputime.py -h
 usage: offcputime.py [-h] [-p PID | -t TID | -u | -k] [-U | -K] [-d] [-f]
  [--stack-storage-size STACK_STORAGE_SIZE]
+ [-m MIN_BLOCK_TIME] [-M MAX_BLOCK_TIME] [--state STATE]
  [duration]
 
 Summarize off-CPU time by stack trace
@@ -747,11 +748,21 @@ optional arguments:
  --stack-storage-size STACK_STORAGE_SIZE
  the number of unique stack traces that can be stored
  and displayed (default 1024)
+ -m MIN_BLOCK_TIME, --min-block-time MIN_BLOCK_TIME
+ the amount of time in microseconds over which we store
+ traces (default 1)
+ -M MAX_BLOCK_TIME, --max-block-time MAX_BLOCK_TIME
+ the amount of time in microseconds under which we
+ store traces (default U64_MAX)
+ --state STATE filter on this thread state bitmask (eg, 2 ==
+ TASK_UNINTERRUPTIBLE) see include/linux/sched.h
 
 examples:
  ./offcputime # trace off-CPU stack time until Ctrl-C
  ./offcputime 5 # trace for 5 seconds only
  ./offcputime -f 5 # 5 seconds, and output in folded format
+ ./offcputime -m 1000 # trace only events that last more than 1000 usec
+ ./offcputime -M 10000 # trace only events that last less than 10000 usec
  ./offcputime -p 185 # only trace threads for PID 185
  ./offcputime -t 188 # only trace thread 188
  ./offcputime -u # only trace user threads (no kernel)