cluster/afr: Delegate metadata heal with pending xattrs to SHD

Problem:
When metadata-self-heal is triggered on the mount, it blocks
lookup until metadata-self-heal completes. But that can lead
to hangs when lot of clients are accessing a directory which
needs metadata heal and all of them trigger heals waiting
for other clients to complete heal.

Fix:
Only when the heal is needed but the pending xattrs are not set,
trigger metadata heal that could block lookup. This is the only
case where different clients may give different metadata to the
clients without heals, which should be avoided.

Updates bz#1625588
Change-Id: I6089e9fda0770a83fb287941b229c882711f4e66
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>

5 files changed, 72 insertions, 51 deletions

diff --git a/tests/basic/afr/client-side-heal.t b/tests/basic/afr/client-side-heal.t
index eba7dc2b3c4..1e9336184b5 100755
--- a/tests/basic/afr/client-side-heal.t
+++ b/tests/basic/afr/client-side-heal.t
@@ -17,6 +17,7 @@ TEST $GFS --volfile-id=$V0 --volfile-server=$H0 $M0;
 echo "some data" > $M0/datafile
 EXPECT 0 echo $?
 TEST touch $M0/mdatafile
+TEST touch $M0/mdatafile-backend-direct-modify
 TEST mkdir $M0/dir
 
 #Kill a brick and perform I/O to have pending heals.
@@ -29,6 +30,7 @@ EXPECT 0 echo $?
 
 #pending metadata heal
 TEST chmod +x $M0/mdatafile
+TEST chmod +x $B0/${V0}0/mdatafile-backend-direct-modify
 
 #pending entry heal. Also causes pending metadata/data heals on file{1..5}
 TEST touch $M0/dir/file{1..5}
@@ -40,9 +42,12 @@ TEST $CLI volume start $V0 force
 EXPECT_WITHIN $PROCESS_UP_TIMEOUT "1" afr_child_up_status $V0 0
 
 #Medatada heal via explicit lookup must not happen
-TEST ls $M0/mdatafile
+TEST getfattr -d -m. -e hex $M0/mdatafile
+TEST ls $M0/mdatafile-backend-direct-modify
 
-#Inode refresh must not trigger data and entry heals.
+TEST [[ "$(stat -c %A $B0/${V0}0/mdatafile-backend-direct-modify)" != "$(stat -c %A $B0/${V0}1/mdatafile-backend-direct-modify)" ]]
+
+#Inode refresh must not trigger data metadata and entry heals.
 #To trigger inode refresh for sure, the volume is unmounted and mounted each time.
 #Check that data heal does not happen.
 EXPECT_WITHIN $UMOUNT_TIMEOUT "Y" force_umount $M0
@@ -52,7 +57,6 @@ TEST cat $M0/datafile
 EXPECT_WITHIN $UMOUNT_TIMEOUT "Y" force_umount $M0
 TEST $GFS --volfile-id=$V0 --volfile-server=$H0 $M0;
 TEST ls $M0/dir
-
 #No heal must have happened
 EXPECT 8 get_pending_heal_count $V0
 
@@ -61,21 +65,25 @@ TEST $CLI volume set $V0 cluster.data-self-heal on
 TEST $CLI volume set $V0 cluster.metadata-self-heal on
 TEST $CLI volume set $V0 cluster.entry-self-heal on
 
-#Metadata heal is triggered by lookup without need for inode refresh.
-TEST ls $M0/mdatafile
-EXPECT 7 get_pending_heal_count $V0
-
-#Inode refresh must trigger data and entry heals.
+#Inode refresh must trigger data metadata and entry heals.
 #To trigger inode refresh for sure, the volume is unmounted and mounted each time.
 EXPECT_WITHIN $UMOUNT_TIMEOUT "Y" force_umount $M0
 TEST $GFS --volfile-id=$V0 --volfile-server=$H0 $M0;
+TEST ls $M0/mdatafile-backend-direct-modify
+
+TEST [[ "$(stat -c %A $B0/${V0}0/mdatafile-backend-direct-modify)" == "$(stat -c %A $B0/${V0}1/mdatafile-backend-direct-modify)" ]]
+
+
+TEST getfattr -d -m. -e hex $M0/mdatafile
+EXPECT_WITHIN $HEAL_TIMEOUT 7 get_pending_heal_count $V0
+
 TEST cat $M0/datafile
 EXPECT_WITHIN $HEAL_TIMEOUT 6 get_pending_heal_count $V0
 
 EXPECT_WITHIN $UMOUNT_TIMEOUT "Y" force_umount $M0
 TEST $GFS --volfile-id=$V0 --volfile-server=$H0 $M0;
 TEST ls $M0/dir
-EXPECT 5 get_pending_heal_count $V0
+EXPECT_WITHIN $HEAL_TIMEOUT 5 get_pending_heal_count $V0
 
 TEST cat  $M0/dir/file1
 TEST cat  $M0/dir/file2
@@ -83,5 +91,5 @@ TEST cat  $M0/dir/file3
 TEST cat  $M0/dir/file4
 TEST cat  $M0/dir/file5
 
-EXPECT 0 get_pending_heal_count $V0
+EXPECT_WITHIN $HEAL_TIMEOUT 0 get_pending_heal_count $V0
 cleanup;
diff --git a/tests/bugs/glusterfs/bug-906646.t b/tests/bugs/glusterfs/bug-906646.t
index 45c85d9f67c..37b8fe5c8eb 100644
--- a/tests/bugs/glusterfs/bug-906646.t
+++ b/tests/bugs/glusterfs/bug-906646.t
@@ -13,7 +13,6 @@ TEST pidof glusterd
 TEST $CLI volume create $V0 replica $REPLICA $H0:$B0/${V0}-00 $H0:$B0/${V0}-01 $H0:$B0/${V0}-10 $H0:$B0/${V0}-11
 TEST $CLI volume start $V0
 
-TEST $CLI volume set $V0 cluster.self-heal-daemon off
 TEST $CLI volume set $V0 cluster.background-self-heal-count 0
 
 ## Mount FUSE with caching disabled
@@ -82,10 +81,15 @@ EXPECT 1 xattr_query_check ${backend_paths_array[1]} "trusted.name"
 # restart the brick process
 TEST $CLI volume start $V0 force
 
-EXPECT_WITHIN $CHILD_UP_TIMEOUT "1" afr_child_up_status $V0 `expr $brick_id - 1`
+EXPECT_WITHIN $PROCESS_UP_TIMEOUT "Y" glustershd_up_status
+EXPECT_WITHIN $CHILD_UP_TIMEOUT "1" afr_child_up_status_in_shd $V0 0
+EXPECT_WITHIN $CHILD_UP_TIMEOUT "1" afr_child_up_status_in_shd $V0 1
+EXPECT_WITHIN $CHILD_UP_TIMEOUT "1" afr_child_up_status_in_shd $V0 2
+EXPECT_WITHIN $CHILD_UP_TIMEOUT "1" afr_child_up_status_in_shd $V0 3
 
-cat $pth >/dev/null
+TEST $CLI volume heal $V0
 
+EXPECT_WITHIN $HEAL_TIMEOUT "0" get_pending_heal_count $V0
 # check backends - xattr should not be present anywhere
 EXPECT 1 xattr_query_check ${backend_paths_array[0]} "trusted.name"
 EXPECT 1 xattr_query_check ${backend_paths_array[1]} "trusted.name"
diff --git a/xlators/cluster/afr/src/afr-common.c b/xlators/cluster/afr/src/afr-common.c
index f17ae09cccd..aa054541755 100644
--- a/xlators/cluster/afr/src/afr-common.c
+++ b/xlators/cluster/afr/src/afr-common.c
@@ -2575,6 +2575,42 @@ out:
         return 0;
 }
 
+gf_boolean_t
+afr_is_pending_set (xlator_t *this, dict_t *xdata, int type)
+{
+        int idx = -1;
+        afr_private_t *priv = NULL;
+        void *pending_raw = NULL;
+        int *pending_int = NULL;
+        int i = 0;
+
+        priv = this->private;
+        idx = afr_index_for_transaction_type (type);
+
+        if (dict_get_ptr (xdata, AFR_DIRTY, &pending_raw) == 0) {
+                if (pending_raw) {
+                        pending_int = pending_raw;
+
+                        if (ntoh32 (pending_int[idx]))
+                                return _gf_true;
+                }
+        }
+
+        for (i = 0; i < priv->child_count; i++) {
+                if (dict_get_ptr (xdata, priv->pending_key[i],
+                                  &pending_raw))
+                        continue;
+                if (!pending_raw)
+                        continue;
+                pending_int = pending_raw;
+
+                if (ntoh32 (pending_int[idx]))
+                        return _gf_true;
+        }
+
+        return _gf_false;
+}
+
 static gf_boolean_t
 afr_can_start_metadata_self_heal(call_frame_t *frame, xlator_t *this)
 {
@@ -2601,6 +2637,14 @@ afr_can_start_metadata_self_heal(call_frame_t *frame, xlator_t *this)
                         continue;
                 }
 
+                if (afr_is_pending_set (this, replies[i].xdata,
+                                        AFR_METADATA_TRANSACTION)) {
+                        /* Let shd do the heal so that lookup is not blocked
+                         * on getting metadata lock/doing the heal */
+                        start = _gf_false;
+                        break;
+                }
+
                 if (gf_uuid_compare (stbuf.ia_gfid, replies[i].poststat.ia_gfid)) {
                         start = _gf_false;
                         break;
diff --git a/xlators/cluster/afr/src/afr-self-heal-common.c b/xlators/cluster/afr/src/afr-self-heal-common.c
index c2d5058081c..a84386d0afb 100644
--- a/xlators/cluster/afr/src/afr-self-heal-common.c
+++ b/xlators/cluster/afr/src/afr-self-heal-common.c
@@ -2176,44 +2176,6 @@ afr_selfheal_unentrylk (call_frame_t *frame, xlator_t *this, inode_t *inode,
 	return 0;
 }
 
-
-gf_boolean_t
-afr_is_pending_set (xlator_t *this, dict_t *xdata, int type)
-{
-	int idx = -1;
-	afr_private_t *priv = NULL;
-	void *pending_raw = NULL;
-	int *pending_int = NULL;
-	int i = 0;
-
-	priv = this->private;
-	idx = afr_index_for_transaction_type (type);
-
-	if (dict_get_ptr (xdata, AFR_DIRTY, &pending_raw) == 0) {
-		if (pending_raw) {
-			pending_int = pending_raw;
-
-			if (ntoh32 (pending_int[idx]))
-				return _gf_true;
-		}
-	}
-
-	for (i = 0; i < priv->child_count; i++) {
-		if (dict_get_ptr (xdata, priv->pending_key[i],
-				  &pending_raw))
-			continue;
-		if (!pending_raw)
-			continue;
-		pending_int = pending_raw;
-
-		if (ntoh32 (pending_int[idx]))
-			return _gf_true;
-	}
-
-	return _gf_false;
-}
-
-
 gf_boolean_t
 afr_is_data_set (xlator_t *this, dict_t *xdata)
 {
diff --git a/xlators/cluster/afr/src/afr.h b/xlators/cluster/afr/src/afr.h
index 36333a3cfaa..8d11f2bb644 100644
--- a/xlators/cluster/afr/src/afr.h
+++ b/xlators/cluster/afr/src/afr.h
@@ -1287,4 +1287,7 @@ afr_write_subvol_reset (call_frame_t *frame, xlator_t *this);
 
 int
 afr_set_inode_local (xlator_t *this, afr_local_t *local, inode_t *inode);
+
+gf_boolean_t
+afr_is_pending_set (xlator_t *this, dict_t *xdata, int type);
 #endif /* __AFR_H__ */