create qa/workunits/rbd/map-unmap.sh

This adds a bash script that creates an rbd image, then repeatedly
maps and unmaps it for a specified duration (5 minutes by default).

Signed-off-by: Alex Elder <elder@inktank.com>

diff --git a/qa/workunits/rbd/map-unmap.sh b/qa/workunits/rbd/map-unmap.sh
new file mode 100755 (executable)
index 0000000..9ecc226
--- /dev/null
+++ b/qa/workunits/rbd/map-unmap.sh
@@ -0,0 +1,98 @@
+#!/bin/bash -e
+
+RUN_TIME=300           # approximate duration of run (seconds)
+
+[ $# -eq 1 ] && RUN_TIME="$1"
+
+IMAGE_NAME="image-$$"
+IMAGE_SIZE="1024"      # MB
+
+ID_TIMEOUT="10"                # seconds to wait to get rbd id after mapping
+ID_DELAY=".1"          # floating-point seconds to delay before rescan
+
+MAP_DELAY=".25"                # floating-point seconds to delay before unmap
+
+function get_time() {
+       date '+%s'
+}
+
+function times_up() {
+       local end_time="$1"
+
+       test $(get_time) -ge "${end_time}"
+}
+
+function get_id() {
+       [ $# -eq 1 ] || exit 99
+       local image_name="$1"
+       local id=""
+       local end_time=$(expr $(get_time) + ${ID_TIMEOUT})
+
+       cd /sys/bus/rbd/devices
+
+       while [ -z "${id}" ]; do
+               if times_up "${end_time}"; then
+                       break;
+               fi
+               for i in *; do
+                       if [ "$(cat $i/name)" = "${image_name}" ]; then
+                               id=$i
+                               break
+                       fi
+               done
+               sleep "${ID_DELAY}"
+       done
+       echo $id
+       test -n "${id}"         # return code 0 if id was found
+}
+
+function map_unmap() {
+       [ $# -eq 1 ] || exit 99
+       local image_name="$1"
+
+       rbd map "${image_name}"
+       RBD_ID=$(get_id "${image_name}")
+
+       sleep "${MAP_DELAY}"
+
+       rbd unmap "/dev/rbd${RBD_ID}"
+}
+
+function setup() {
+       [ $# -eq 2 ] || exit 99
+       local image_name="$1"
+       local image_size="$2"
+
+       [ -d /sys/bus/rbd ] || sudo modprobe rbd
+
+       # allow ubuntu user to map/unmap rbd devices
+       sudo chown ubuntu /sys/bus/rbd/add
+       sudo chown ubuntu /sys/bus/rbd/remove
+       rbd create "${image_name}" --size="${image_size}"
+}
+
+function cleanup() {
+       # Have to rely on globals for the trap call
+       # rbd unmap "/dev/rbd${RBD_ID}"         || true
+       rbd rm "${IMAGE_NAME}"                  || true
+       sudo chown root /sys/bus/rbd/remove     || true
+       sudo chown root /sys/bus/rbd/add        || true
+}
+trap cleanup EXIT HUP INT
+
+#### Start
+
+setup "${IMAGE_NAME}" "${IMAGE_SIZE}"
+
+COUNT=0
+START_TIME=$(get_time)
+END_TIME=$(expr $(get_time) + ${RUN_TIME})
+while ! times_up "${END_TIME}"; do
+       map_unmap "${IMAGE_NAME}"
+       COUNT=$(expr $COUNT + 1)
+done
+ELAPSED=$(expr "$(get_time)" - "${START_TIME}")
+
+echo "${COUNT} iterations completed in ${ELAPSED} seconds"
+
+exit 0