ceph: queue cap release in __ceph_remove_cap()

call __queue_cap_release() in __ceph_remove_cap(), this avoids
acquiring s_cap_lock twice.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Reviewed-by: Sage Weil <sage@inktank.com>

3 files changed, 14 insertions, 21 deletions

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 13976c33332e..d2d6e40e7345 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -897,7 +897,7 @@ static int __ceph_is_any_caps(struct ceph_inode_info *ci)
  * caller should hold i_ceph_lock.
  * caller will not hold session s_mutex if called from destroy_inode.
  */
-void __ceph_remove_cap(struct ceph_cap *cap)
+void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release)
 {
         struct ceph_mds_session *session = cap->session;
         struct ceph_inode_info *ci = cap->ci;
@@ -909,6 +909,10 @@ void __ceph_remove_cap(struct ceph_cap *cap)
 
         /* remove from session list */
         spin_lock(&session->s_cap_lock);
+        if (queue_release)
+                __queue_cap_release(session, ci->i_vino.ino, cap->cap_id,
+                                    cap->mseq, cap->issue_seq);
+
         if (session->s_cap_iterator == cap) {
                 /* not yet, we are iterating over this very cap */
                 dout("__ceph_remove_cap  delaying %p removal from session %p\n",
@@ -1023,7 +1027,6 @@ void __queue_cap_release(struct ceph_mds_session *session,
         struct ceph_mds_cap_release *head;
         struct ceph_mds_cap_item *item;
 
-        spin_lock(&session->s_cap_lock);
         BUG_ON(!session->s_num_cap_releases);
         msg = list_first_entry(&session->s_cap_releases,
                                struct ceph_msg, list_head);
@@ -1052,7 +1055,6 @@ void __queue_cap_release(struct ceph_mds_session *session,
                      (int)CEPH_CAPS_PER_RELEASE,
                      (int)msg->front.iov_len);
         }
-        spin_unlock(&session->s_cap_lock);
 }
 
 /*
@@ -1067,12 +1069,8 @@ void ceph_queue_caps_release(struct inode *inode)
         p = rb_first(&ci->i_caps);
         while (p) {
                 struct ceph_cap *cap = rb_entry(p, struct ceph_cap, ci_node);
-                struct ceph_mds_session *session = cap->session;
-
-                __queue_cap_release(session, ceph_ino(inode), cap->cap_id,
-                                    cap->mseq, cap->issue_seq);
                 p = rb_next(p);
-                __ceph_remove_cap(cap);
+                __ceph_remove_cap(cap, true);
         }
 }
 
@@ -2791,7 +2789,7 @@ static void handle_cap_export(struct inode *inode, struct ceph_mds_caps *ex,
                         }
                         spin_unlock(&mdsc->cap_dirty_lock);
                 }
-                __ceph_remove_cap(cap);
+                __ceph_remove_cap(cap, false);
         }
         /* else, we already released it */
 
@@ -2931,9 +2929,12 @@ void ceph_handle_caps(struct ceph_mds_session *session,
         if (!inode) {
                 dout(" i don't have ino %llx\n", vino.ino);
 
-                if (op == CEPH_CAP_OP_IMPORT)
+                if (op == CEPH_CAP_OP_IMPORT) {
+                        spin_lock(&session->s_cap_lock);
                         __queue_cap_release(session, vino.ino, cap_id,
                                             mseq, seq);
+                        spin_unlock(&session->s_cap_lock);
+                }
                 goto flush_cap_releases;
         }
 
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index f51ab2627b41..8f8f5c043c37 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -986,7 +986,7 @@ static int remove_session_caps_cb(struct inode *inode, struct ceph_cap *cap,
         dout("removing cap %p, ci is %p, inode is %p\n",
              cap, ci, &ci->vfs_inode);
         spin_lock(&ci->i_ceph_lock);
-        __ceph_remove_cap(cap);
+        __ceph_remove_cap(cap, false);
         if (!__ceph_is_any_real_caps(ci)) {
                 struct ceph_mds_client *mdsc =
                         ceph_sb_to_client(inode->i_sb)->mdsc;
@@ -1231,9 +1231,7 @@ static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg)
         session->s_trim_caps--;
         if (oissued) {
                 /* we aren't the only cap.. just remove us */
-                __queue_cap_release(session, ceph_ino(inode), cap->cap_id,
-                                    cap->mseq, cap->issue_seq);
-                __ceph_remove_cap(cap);
+                __ceph_remove_cap(cap, true);
         } else {
                 /* try to drop referring dentries */
                 spin_unlock(&ci->i_ceph_lock);
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 6014b0a3c405..ef4ac38bb614 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -741,13 +741,7 @@ extern int ceph_add_cap(struct inode *inode,
                         int fmode, unsigned issued, unsigned wanted,
                         unsigned cap, unsigned seq, u64 realmino, int flags,
                         struct ceph_cap_reservation *caps_reservation);
-extern void __ceph_remove_cap(struct ceph_cap *cap);
-static inline void ceph_remove_cap(struct ceph_cap *cap)
-{
-        spin_lock(&cap->ci->i_ceph_lock);
-        __ceph_remove_cap(cap);
-        spin_unlock(&cap->ci->i_ceph_lock);
-}
+extern void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release);
 extern void ceph_put_cap(struct ceph_mds_client *mdsc,
                          struct ceph_cap *cap);