tools/biolatency: Handle signals from user

tools/biolatency.py

@@ -15,6 +15,7 @@
 from bcc import BPF
 from time import sleep, strftime
 import argparse
+import signal
 
 # arguments
 examples = """examples:
@@ -193,15 +194,7 @@ def flags_print(flags):
         desc = "NoWait-" + desc
     return desc
 
-# output
-exiting = 0 if args.interval else 1
-dist = b.get_table("dist")
-while (1):
-    try:
-        sleep(int(args.interval))
-    except KeyboardInterrupt:
-        exiting = 1
-
+def print_hist():
     print()
     if args.timestamp:
         print("%-8s\n" % strftime("%H:%M:%S"), end="")
@@ -212,6 +205,28 @@ def flags_print(flags):
         dist.print_log2_hist(label, "disk")
     dist.clear()
 
+def exit_handler():
+    print_hist()
+    exit()
+
+def signal_handler(sig, frame):
+    exit_handler()
+
+signal.signal(signal.SIGTERM, signal_handler)
+signal.signal(signal.SIGINT, signal_handler)
+signal.signal(signal.SIGQUIT, signal_handler)
+
+exiting = 0 if args.interval else 1
+dist = b.get_table("dist")
+
+while (1):
+    try:
+        sleep(int(args.interval))
+    except KeyboardInterrupt:
+        exiting = 1
+
+    print_hist()
+
     countdown -= 1
     if exiting or countdown == 0:
-        exit()
+        exit_handler()