From 4a4794364eb05f7f6cb4600af986951353d034f4 Mon Sep 17 00:00:00 2001
From: Lai Siyao <lai.siyao@whamcloud.com>
Date: Tue, 22 Sep 2020 19:05:51 +0800
Subject: [PATCH] LU-13983 llite: rmdir releases inode on client

Same as file unlink, rmdir should release inode on client, to achieve
this, ll_rmdir() update inode i_nlink after rmdir, then the last
iput() will release the inode.

Signed-off-by: Lai Siyao <lai.siyao@whamcloud.com>
Change-Id: I9181151de1830b48986afec30c83120e9f112a85
Reviewed-on: https://review.whamcloud.com/40011
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Yingjin Qian <qian@ddn.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
---
 lustre/llite/namei.c   | 20 ++++++++++++++++----
 lustre/tests/sanity.sh | 32 ++++++++++++++++++++++++++++++--
 2 files changed, 46 insertions(+), 6 deletions(-)

diff --git a/lustre/llite/namei.c b/lustre/llite/namei.c
index b84dfd7..4d0babd 100644
--- a/lustre/llite/namei.c
+++ b/lustre/llite/namei.c
@@ -1692,13 +1692,25 @@ static int ll_rmdir(struct inode *dir, struct dentry *dchild)
 	op_data->op_fid2 = op_data->op_fid3;
 	rc = md_unlink(ll_i2sbi(dir)->ll_md_exp, op_data, &request);
 	ll_finish_md_op_data(op_data);
-	if (!rc)
-		ll_update_times(request, dir);
+	if (!rc) {
+		struct mdt_body *body;
 
-	ptlrpc_req_finished(request);
-	if (!rc)
+		ll_update_times(request, dir);
 		ll_stats_ops_tally(ll_i2sbi(dir), LPROC_LL_RMDIR,
 				   ktime_us_delta(ktime_get(), kstart));
+
+		/*
+		 * The server puts attributes in on the last unlink, use them
+		 * to update the link count so the inode can be freed
+		 * immediately.
+		 */
+		body = req_capsule_server_get(&request->rq_pill, &RMF_MDT_BODY);
+		if (body->mbo_valid & OBD_MD_FLNLINK)
+			set_nlink(dchild->d_inode, body->mbo_nlink);
+	}
+
+	ptlrpc_req_finished(request);
+
 	RETURN(rc);
 }
 
diff --git a/lustre/tests/sanity.sh b/lustre/tests/sanity.sh
index a6d2294..4117554 100755
--- a/lustre/tests/sanity.sh
+++ b/lustre/tests/sanity.sh
@@ -8642,7 +8642,7 @@ num_objects() {
 		awk '/lustre_inode_cache/ { print $2; exit }' /proc/slabinfo
 }
 
-test_76() { # Now for b=20433, added originally in b=1443
+test_76a() { # Now for b=20433, added originally in b=1443
 	[ $PARALLEL == "yes" ] && skip "skip parallel run"
 
 	cancel_lru_locks osc
@@ -8677,8 +8677,36 @@ test_76() { # Now for b=20433, added originally in b=1443
 		fi
 	done
 }
-run_test 76 "confirm clients recycle inodes properly ===="
+run_test 76a "confirm clients recycle inodes properly ===="
 
+test_76b() {
+	[ $PARALLEL == "yes" ] && skip "skip parallel run"
+	[ $CLIENT_VERSION -ge $(version_code 2.13.55) ] || skip "not supported"
+
+	local count=512
+	local before=$(num_objects)
+
+	for i in $(seq $count); do
+		mkdir $DIR/$tdir
+		rmdir $DIR/$tdir
+	done
+
+	local after=$(num_objects)
+	local wait=0
+
+	while (( after > before )); do
+		sleep 1
+		after=$(num_objects)
+		wait=$((wait + 1))
+		(( wait % 5 == 0 )) && echo "wait $wait seconds objects: $after"
+		if (( wait > 60 )); then
+			error "inode slab grew from $before to $after"
+		fi
+	done
+
+	echo "slab objects before: $before, after: $after"
+}
+run_test 76b "confirm clients recycle directory inodes properly ===="
 
 export ORIG_CSUM=""
 set_checksums()
-- 
1.8.3.1