2 files changed, 36 insertions, 0 deletions
diff --git a/systemtap/ioblock_delay/device.sh b/systemtap/ioblock_delay/device.sh
new file mode 100755
index 0000000..1bb5ba3
--- /dev/null
+++ b/systemtap/ioblock_delay/device.sh
@@ -0,0 +1,5 @@
+#!/bin/sh
+
+test -e "/dev/$1" || { echo "USAGE: $0 <devicename without prefix>"; exit 1; }
+
+stap -c "dd if=\"/dev/$1\" of=/dev/null bs=1M" device.stp "$1"
diff --git a/systemtap/ioblock_delay/device.stp b/systemtap/ioblock_delay/device.stp
new file mode 100755
index 0000000..b9270e5
--- /dev/null
+++ b/systemtap/ioblock_delay/device.stp
@@ -0,0 +1,31 @@
+// size of array equals to max. number of pending requests
+global calls[30000];
+
+probe begin {
+    printf("device,sector,time_ns\n");
+}
+
+probe ioblock.request
+{
+    if (devname == @1) {
+        calls[$bio] = gettimeofday_ns();
+    }
+}
+
+probe ioblock.end
+{
+   if ([$bio] in calls) {
+     time = gettimeofday_ns() - calls[$bio];
+     delete calls[$bio];
+
+     printf("%s,%u,%ld\n",
+            devname, sector, time);
+   }
+}
+
+probe end {
+  foreach ([bio] in calls) {
+    printf("# Lost: %s,%u,%u\n", 
+           __bio_devname(bio), @cast(bio, "bio")->bi_sector, calls[bio]);
+  }
+}