afr/split-brain: fix client side split-brain resolution when quorum is enabled

Problem:
If we set favourite child policy, then automatic split-brain resolution
should work in all cases. This was failing when quorum count was set to
a non-zero value. The initial lookup before the read txn was failing
with ENOTCONN. Since we don't have a readable subvol, we were failing it.
We were only looking to the split brain resolution choice set through the
cli command.

Fix:
We will now consider the favourite child policy if split-brain choice
has not been set via cli command.

Change-Id: Id2016c3a90d0763ac6f1a0131571053f595576f0
Fixes: #1404
Signed-off-by: Mohammed Rafi KC <rafi.kavungal@iternity.com>

1 files changed, 124 insertions, 0 deletions

diff --git a/tests/basic/afr/split-brain-favorite-child-policy-client-side-healing.t b/tests/basic/afr/split-brain-favorite-child-policy-client-side-healing.t
new file mode 100644
index 00000000000..7c249c4bcbd
--- /dev/null
+++ b/tests/basic/afr/split-brain-favorite-child-policy-client-side-healing.t
@@ -0,0 +1,124 @@
+#!/bin/bash
+
+#Test the client side split-brain resolution
+. $(dirname $0)/../../include.rc
+. $(dirname $0)/../../volume.rc
+
+cleanup;
+
+GET_MDATA_PATH=$(dirname $0)/../../utils
+build_tester $GET_MDATA_PATH/get-mdata-xattr.c
+
+TEST glusterd
+TEST pidof glusterd
+
+count_files () {
+         ls $1 | wc -l
+}
+
+#Create replica 2 volume
+TEST $CLI volume create $V0 replica 2 $H0:$B0/${V0}{0,1}
+TEST $CLI volume set $V0 performance.write-behind off
+TEST $CLI volume heal $V0 disable
+TEST $CLI volume set $V0 cluster.quorum-type fixed
+TEST $CLI volume set $V0 cluster.quorum-count 1
+TEST $CLI volume set $V0 cluster.metadata-self-heal on
+TEST $CLI volume set $V0 cluster.data-self-heal on
+TEST $CLI volume set $V0 cluster.entry-self-heal on
+
+TEST $CLI volume start $V0
+TEST $GFS --volfile-id=/$V0 --volfile-server=$H0 $M0
+EXPECT_WITHIN $CHILD_UP_TIMEOUT "1" afr_child_up_status $V0 0
+EXPECT_WITHIN $CHILD_UP_TIMEOUT "1" afr_child_up_status $V0 1
+
+TEST mkdir $M0/data
+TEST touch $M0/data/file
+
+
+############ Client side healing using favorite-child-policy = mtime #################
+TEST kill_brick $V0 $H0 $B0/${V0}0
+TEST dd if=/dev/urandom of=$M0/data/file bs=1024 count=1024
+TEST $CLI volume start $V0 force
+EXPECT_WITHIN $PROCESS_UP_TIMEOUT "1" brick_up_status $V0 $H0 $B0/${V0}0
+EXPECT_WITHIN $PROCESS_UP_TIMEOUT "1" afr_child_up_status $V0 0
+TEST kill_brick $V0 $H0 $B0/${V0}1
+TEST dd if=/dev/urandom of=$M0/data/file bs=1024 count=1024
+
+TEST $CLI volume start $V0 force
+EXPECT_WITHIN $PROCESS_UP_TIMEOUT "1" brick_up_status $V0 $H0 $B0/${V0}1
+EXPECT_WITHIN $PROCESS_UP_TIMEOUT "1" afr_child_up_status $V0 1
+
+mtime1=$(get_mtime $B0/${V0}0/data/file)
+mtime2=$(get_mtime $B0/${V0}1/data/file)
+if (( $(echo "$mtime1 > $mtime2" | bc -l) )); then
+        LATEST_MTIME_MD5=$(md5sum $B0/${V0}0/data/file | cut -d\  -f1)
+else
+        LATEST_MTIME_MD5=$(md5sum $B0/${V0}1/data/file | cut -d\  -f1)
+fi
+
+#file will be in split-brain
+cat $M0/data/file > /dev/null
+EXPECT "1" echo $?
+
+TEST $CLI volume set $V0 cluster.favorite-child-policy mtime
+TEST $CLI volume start $V0 force
+
+EXPECT_WITHIN $HEAL_TIMEOUT "^2$" afr_get_split_brain_count $V0
+cat $M0/data/file > /dev/null
+EXPECT "0" echo $?
+M0_MD5=$(md5sum $M0/data/file | cut -d\  -f1)
+EXPECT_WITHIN $HEAL_TIMEOUT "^0$" afr_get_split_brain_count $V0
+TEST [ "$LATEST_MTIME_MD5" == "$M0_MD5" ]
+
+EXPECT_WITHIN $HEAL_TIMEOUT "^0$" get_pending_heal_count $V0
+
+B0_MD5=$(md5sum $B0/${V0}0/data/file | cut -d\  -f1)
+B1_MD5=$(md5sum $B0/${V0}1/data/file | cut -d\  -f1)
+TEST [ "$LATEST_MTIME_MD5" == "$B0_MD5" ]
+TEST [ "$LATEST_MTIME_MD5" == "$B1_MD5" ]
+
+############ Client side directory conservative merge #################
+TEST $CLI volume reset $V0 cluster.favorite-child-policy
+TEST kill_brick $V0 $H0 $B0/${V0}0
+TEST touch $M0/data/test
+files=$(count_files $M0/data)
+EXPECT "2" echo $files
+TEST $CLI volume start $V0 force
+EXPECT_WITHIN $PROCESS_UP_TIMEOUT "1" brick_up_status $V0 $H0 $B0/${V0}0
+EXPECT_WITHIN $PROCESS_UP_TIMEOUT "1" afr_child_up_status $V0 0
+TEST kill_brick $V0 $H0 $B0/${V0}1
+TEST touch $M0/data/test1
+files=$(count_files $M0/data)
+EXPECT "2" echo $files
+
+TEST $CLI volume start $V0 force
+EXPECT_WITHIN $PROCESS_UP_TIMEOUT "1" brick_up_status $V0 $H0 $B0/${V0}1
+EXPECT_WITHIN $PROCESS_UP_TIMEOUT "1" afr_child_up_status $V0 1
+
+#data dir will be in entry split-brain
+ls $M0/data > /dev/null
+EXPECT "2" echo $?
+
+TEST $CLI volume set $V0 cluster.favorite-child-policy mtime
+
+EXPECT_WITHIN $HEAL_TIMEOUT "^2$" afr_get_split_brain_count $V0
+
+
+ls $M0/data > /dev/null
+EXPECT "0" echo $?
+
+EXPECT_WITHIN $HEAL_TIMEOUT "^0$" afr_get_split_brain_count $V0
+#Entry Split-brain is gone, but data self-heal is pending on the files
+EXPECT_WITHIN $HEAL_TIMEOUT "^2$" get_pending_heal_count $V0
+
+cat $M0/data/test > /dev/null
+cat $M0/data/test1 > /dev/null
+
+EXPECT_WITHIN $HEAL_TIMEOUT "^0$" get_pending_heal_count $V0
+files=$(count_files $M0/data)
+EXPECT "3" echo $files
+
+TEST force_umount $M0
+TEST rm $GET_MDATA_PATH/get-mdata-xattr
+
+cleanup