Add conditions in the I/O scheduler

Due to the way /etc/udev/rules.d/60-io-scheduler.rules is
written, it doesn't check if the I/O scheduler is already
set correctly or not, before resetting it. Thus, a condition
was added to each "action", in such a way that only the
correct "action" is executed.

Using gparted/sgdisk in sysinv causes disks to be "reprobed"
by the kernel every minute, so the disk I/O scheduler is reset
multiple times. This can be seen by running the command below:

sysadmin@controller-0:~$ ( while true; do sched="$(cat /sys/block
/sda/queue/scheduler)"; if test "${sched}" != "${last_sched}";
then echo "$(date -Is): change: ${sched}"; last_sched="${sched}";
fi; done )

Test Plan:
PASS: It was checked disk I/O scheduler (sys/block/sda/queue
/scheduler) is not resetting every minute, multiple times on
AIO-SX fresh install.

Closes-Bug: 1996822

Signed-off-by: Erickson Silva de Oliveira <Erickson.SilvadeOliveira@windriver.com>
Change-Id: Ic4a9b963d00393b591fd23f2c1224ad6b8740e5e

io-scheduler/source-debian/60-io-scheduler.rules

@@ -70,20 +70,61 @@ IMPORT{file}="/etc/platform/platform.conf"
 # - Virtual guest: Use mq-deadline. With a host bus adapter (HBA) driver that
 #   is multi-queue capable, use none.
 
-ACTION=="add|change", SUBSYSTEM=="block", KERNEL=="sd[a-z]", \
-    ATTR{queue/scheduler}="mq-deadline", \
-    ATTR{queue/iosched/front_merges}="0", \
-    ATTR{queue/iosched/read_expire}="150", \
-    ATTR{queue/iosched/write_expire}="1500"
+ACTION!="add|change", GOTO="iosched_end"
+SUBSYSTEM!="block", GOTO="iosched_end"
+KERNEL!="sd[a-z]", GOTO="iosched_end"
 
+PROGRAM="/usr/local/bin/is-rootdisk-device.sh %E{DEVNAME}", RESULT=="?*", ENV{rootdisk}="1"
 
-ACTION=="add|change", ENV{nodetype}=="controller", SUBSYSTEM=="block", KERNEL=="sd[a-z]", \
-    PROGRAM="/usr/local/bin/is-rootdisk-device.sh %E{DEVNAME}", RESULT=="?*", \
-    ATTR{queue/scheduler}="bfq", \
-    ATTR{queue/iosched/strict_guarantees}="1"
+# === === === ===
+# Check the I/O scheduler settings are correct.
+# === === === ===
+
+ATTRS{raid_level}=="*RAID*", \
+    ATTR{queue/scheduler}=="*\[none\]*", \
+    GOTO="iosched_end"
+
+ATTRS{label}=="*RAID*", \
+    ATTR{queue/scheduler}=="*\[none\]*", \
+    GOTO="iosched_end"
+
+ENV{nodetype}=="controller", \
+    ENV{rootdisk}=="1", \
+    ATTR{queue/scheduler}=="*\[bfq\]*", \
+    ATTR{queue/iosched/strict_guarantees}=="1", \
+    GOTO="iosched_end"
+
+ATTR{queue/scheduler}=="*\[mq-deadline\]*", \
+    ATTR{queue/iosched/front_merges}=="0", \
+    ATTR{queue/iosched/read_expire}=="150", \
+    ATTR{queue/iosched/write_expire}=="1500", \
+    GOTO="iosched_end"
+
+# === === === ===
+# I/O scheduler settings are not as expected, need to be defined.
+# === === === ===
 
 # Set none io scheduler for variants of HW-RAID.
 # HP ProLiant DL360p Gen8; HP ProLiant DL380p Gen8
-ACTION=="add|change", SUBSYSTEM=="block", KERNEL=="sd[a-z]", ATTRS{raid_level}=="*RAID*", ATTR{queue/scheduler}="none"
+ATTRS{raid_level}=="*RAID*", \
+    ATTR{queue/scheduler}="none", \
+    GOTO="iosched_end"
+
 # Dell Inc. PowerEdge R720
-ACTION=="add|change", SUBSYSTEM=="block", KERNEL=="sd[a-z]", ATTRS{label}=="*RAID*", ATTR{queue/scheduler}="none"
+ATTRS{label}=="*RAID*", \
+    ATTR{queue/scheduler}="none", \
+    GOTO="iosched_end"
+
+ENV{nodetype}=="controller", \
+    ENV{rootdisk}=="1", \
+    ATTR{queue/scheduler}="bfq", \
+    ATTR{queue/iosched/strict_guarantees}="1", \
+    GOTO="iosched_end"
+
+ATTR{queue/scheduler}="mq-deadline", \
+    ATTR{queue/iosched/front_merges}="0", \
+    ATTR{queue/iosched/read_expire}="150", \
+    ATTR{queue/iosched/write_expire}="1500", \
+    GOTO="iosched_end"
+
+LABEL="iosched_end"