From: Sage Weil <sage@newdream.net>
Date: Mon, 25 Apr 2011 18:44:14 +0000 (-0700)
Subject: mds: only move the journaler expire_pos forward
X-Git-Tag: v0.27.1~9
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=e8847b2cddbadf4f31972b490d80944dcb9f992d;p=ceph.git

mds: only move the journaler expire_pos forward

We were seeing weird trim errors because expire_pos was getting moved
backwards after a standby-replay -> replay transition.  Make sure the two
places that update the expire_pos only move it forward--never backward.

Fixes: #1023
Signed-off-by: Sage Weil <sage@newdream.net>
---

diff --git a/src/mds/MDLog.cc b/src/mds/MDLog.cc
index b5e27b876a64..09cfdce7eb42 100644
--- a/src/mds/MDLog.cc
+++ b/src/mds/MDLog.cc
@@ -394,7 +394,9 @@ void MDLog::_expired(LogSegment *ls)
       expired_segments.erase(ls);
       num_events -= ls->num_events;
       
-      journaler->set_expire_pos(ls->offset);  // this was the oldest segment, adjust expire pos
+      // this was the oldest segment, adjust expire pos
+      if (journaler->get_expire_pos() < ls->offset)
+	journaler->set_expire_pos(ls->offset);
       
       logger->set(l_mdl_expos, ls->offset);
       logger->inc(l_mdl_segtrm);
diff --git a/src/mds/journal.cc b/src/mds/journal.cc
index 814fd8d2cad4..09dac9fd8fac 100644
--- a/src/mds/journal.cc
+++ b/src/mds/journal.cc
@@ -1050,6 +1050,7 @@ void ESubtreeMap::replay(MDS *mds)
 {
   if (expire_pos && expire_pos > mds->mdlog->journaler->get_expire_pos())
     mds->mdlog->journaler->set_expire_pos(expire_pos);
+
   // suck up the subtree map?
   if (mds->mdcache->is_subtrees()) {
     dout(10) << "ESubtreeMap.replay -- ignoring, already have import map" << dendl;