[GFS2] Remove remote lock dropping code

There are several reasons why this is undesirable:

 1. It never happens during normal operation anyway
 2. If it does happen it causes performance to be very, very poor
 3. It isn't likely to solve the original problem (memory shortage
    on remote DLM node) it was supposed to solve
 4. It uses a bunch of arbitrary constants which are unlikely to be
    correct for any particular situation and for which the tuning seems
    to be a black art.
 5. In an N node cluster, only 1/N of the dropped locked will actually
    contribute to solving the problem on average.

So all in all we are better off without it. This also makes merging
the lock_dlm module into GFS2 a bit easier.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

1 files changed, 3 insertions, 9 deletions

diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index be7ed503f012..8d5450f3c3ef 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -1316,11 +1316,6 @@ void gfs2_glock_cb(void *cb_data, unsigned int type, void *data)
                         wake_up_process(sdp->sd_recoverd_process);
                 return;
 
-        case LM_CB_DROPLOCKS:
-                gfs2_gl_hash_clear(sdp, NO_WAIT);
-                gfs2_quota_scan(sdp);
-                return;
-
         default:
                 gfs2_assert_warn(sdp, 0);
                 return;
@@ -1508,11 +1503,10 @@ static void clear_glock(struct gfs2_glock *gl)
  * @sdp: the filesystem
  * @wait: wait until it's all gone
  *
- * Called when unmounting the filesystem, or when inter-node lock manager
- * requests DROPLOCKS because it is running out of capacity.
+ * Called when unmounting the filesystem.
  */
 
-void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait)
+void gfs2_gl_hash_clear(struct gfs2_sbd *sdp)
 {
         unsigned long t;
         unsigned int x;
@@ -1527,7 +1521,7 @@ void gfs2_gl_hash_clear(struct gfs2_sbd *sdp, int wait)
                                 cont = 1;
                 }
 
-                if (!wait || !cont)
+                if (!cont)
                         break;
 
                 if (time_after_eq(jiffies,