From: Xiubo Li <xiubli@redhat.com>
Date: Wed, 27 May 2020 09:09:27 -0400
Subject: ceph: skip checking caps when session reconnecting and releasing reqs
Git-commit: e64f44a884657358812e6c057957be546db03cbe
Patch-mainline: v5.8-rc1
References: bsc#1172990

It make no sense to check the caps when reconnecting to mds. And
for the async dirop caps, they will be put by its _cb() function,
so when releasing the requests, it will make no sense too.

URL: https://tracker.ceph.com/issues/45635
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Luis Henriques <lhenriques@suse.com>
---
 fs/ceph/caps.c       | 15 +++++++++++++--
 fs/ceph/mds_client.c | 16 ++++++++++++++--
 fs/ceph/mds_client.h |  1 +
 fs/ceph/super.h      |  2 ++
 4 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 41eb999dadf0..972c13aa4225 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -3016,7 +3016,8 @@ static int ceph_try_drop_cap_snap(struct ceph_inode_info *ci,
  * If we are releasing a WR cap (from a sync write), finalize any affected
  * cap_snap, and wake up any waiters.
  */
-void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
+static void __ceph_put_cap_refs(struct ceph_inode_info *ci, int had,
+				bool skip_checking_caps)
 {
 	struct inode *inode = &ci->vfs_inode;
 	int last = 0, put = 0, flushsnaps = 0, wake = 0;
@@ -3072,7 +3073,7 @@ void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
 	dout("put_cap_refs %p had %s%s%s\n", inode, ceph_cap_string(had),
 	     last ? " last" : "", put ? " put" : "");
 
-	if (last)
+	if (last && !skip_checking_caps)
 		ceph_check_caps(ci, 0, NULL);
 	else if (flushsnaps)
 		ceph_flush_snaps(ci, NULL);
@@ -3082,6 +3083,16 @@ void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
 		iput(inode);
 }
 
+void ceph_put_cap_refs(struct ceph_inode_info *ci, int had)
+{
+	__ceph_put_cap_refs(ci, had, false);
+}
+
+void ceph_put_cap_refs_no_check_caps(struct ceph_inode_info *ci, int had)
+{
+	__ceph_put_cap_refs(ci, had, true);
+}
+
 /*
  * Release @nr WRBUFFER refs on dirty pages for the given @snapc snap
  * context.  Adjust per-snap dirty page accounting as appropriate.
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 0e0ab01694dc..a50497142e59 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -804,7 +804,7 @@ void ceph_mdsc_release_request(struct kref *kref)
 	struct ceph_mds_request *req = container_of(kref,
 						    struct ceph_mds_request,
 						    r_kref);
-	ceph_mdsc_release_dir_caps(req);
+	ceph_mdsc_release_dir_caps_no_check(req);
 	destroy_reply_info(&req->r_reply_info);
 	if (req->r_request)
 		ceph_msg_put(req->r_request);
@@ -3402,6 +3402,18 @@ void ceph_mdsc_release_dir_caps(struct ceph_mds_request *req)
 	}
 }
 
+void ceph_mdsc_release_dir_caps_no_check(struct ceph_mds_request *req)
+{
+	int dcaps;
+
+	dcaps = xchg(&req->r_dir_caps, 0);
+	if (dcaps) {
+		dout("releasing r_dir_caps=%s\n", ceph_cap_string(dcaps));
+		ceph_put_cap_refs_no_check_caps(ceph_inode(req->r_parent),
+						dcaps);
+	}
+}
+
 /*
  * called under session->mutex.
  */
@@ -3434,7 +3446,7 @@ static void replay_unsafe_requests(struct ceph_mds_client *mdsc,
 		if (req->r_session->s_mds != session->s_mds)
 			continue;
 
-		ceph_mdsc_release_dir_caps(req);
+		ceph_mdsc_release_dir_caps_no_check(req);
 
 		__send_request(mdsc, session, req, true);
 	}
diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
index 43111e408fa2..5e0c4073a6be 100644
--- a/fs/ceph/mds_client.h
+++ b/fs/ceph/mds_client.h
@@ -507,6 +507,7 @@ extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
 				struct inode *dir,
 				struct ceph_mds_request *req);
 extern void ceph_mdsc_release_dir_caps(struct ceph_mds_request *req);
+extern void ceph_mdsc_release_dir_caps_no_check(struct ceph_mds_request *req);
 static inline void ceph_mdsc_get_request(struct ceph_mds_request *req)
 {
 	kref_get(&req->r_kref);
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 226f19c9042f..5a6cdd39bc10 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -1095,6 +1095,8 @@ extern void ceph_take_cap_refs(struct ceph_inode_info *ci, int caps,
 				bool snap_rwsem_locked);
 extern void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps);
 extern void ceph_put_cap_refs(struct ceph_inode_info *ci, int had);
+extern void ceph_put_cap_refs_no_check_caps(struct ceph_inode_info *ci,
+					    int had);
 extern void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
 				       struct ceph_snap_context *snapc);
 extern void ceph_flush_snaps(struct ceph_inode_info *ci,