objecter: waive OSDMAP_FULL check for MDS

The MDS expects to be able to perform writes to OSDs even
if the full ratio has been reached, in order to journal
file deletions to free space.

Fixes: #7780
Signed-off-by: John Spray <john.spray@inktank.com>

diff --git a/src/osdc/Objecter.cc b/src/osdc/Objecter.cc
index a2954662605cfb5a0f2b723d4aae3c0ae3ee09c5..08d16e1406456ddeb7d2e4bd6cea4a6d7e7aeb9c 100644 (file)
--- a/src/osdc/Objecter.cc
+++ b/src/osdc/Objecter.cc
@@ -567,7 +567,7 @@ void Objecter::handle_osd_map(MOSDMap *m)
   }
 
   bool was_pauserd = osdmap->test_flag(CEPH_OSDMAP_PAUSERD);
-  bool was_full = osdmap->test_flag(CEPH_OSDMAP_FULL);
+  bool was_full = osdmap_full_flag();
   bool was_pausewr = osdmap->test_flag(CEPH_OSDMAP_PAUSEWR) || was_full;
 
   list<LingerOp*> need_resend_linger;
@@ -618,7 +618,7 @@ void Objecter::handle_osd_map(MOSDMap *m)
        }
        logger->set(l_osdc_map_epoch, osdmap->get_epoch());
 
-       was_full = was_full || osdmap->test_flag(CEPH_OSDMAP_FULL);
+       was_full = was_full || osdmap_full_flag();
        scan_requests(skipped_map, was_full, need_resend, need_resend_linger,
                      need_resend_command);
 
@@ -655,7 +655,7 @@ void Objecter::handle_osd_map(MOSDMap *m)
   }
 
   bool pauserd = osdmap->test_flag(CEPH_OSDMAP_PAUSERD);
-  bool pausewr = osdmap->test_flag(CEPH_OSDMAP_PAUSEWR) || osdmap->test_flag(CEPH_OSDMAP_FULL);
+  bool pausewr = osdmap->test_flag(CEPH_OSDMAP_PAUSEWR) || osdmap_full_flag();
 
   // was/is paused?
   if (was_pauserd || was_pausewr || pauserd || pausewr)
@@ -1021,7 +1021,7 @@ void Objecter::_get_latest_version(epoch_t oldest, epoch_t newest, Context *fin)
 void Objecter::maybe_request_map()
 {
   int flag = 0;
-  if (osdmap->test_flag(CEPH_OSDMAP_FULL)) {
+  if (osdmap_full_flag()) {
     ldout(cct, 10) << "maybe_request_map subscribing (continuous) to next osd map (FULL flag is set)" << dendl;
   } else {
     ldout(cct, 10) << "maybe_request_map subscribing (onetime) to next osd map" << dendl;
@@ -1328,8 +1328,7 @@ tid_t Objecter::_op_submit(Op *op)
     ldout(cct, 10) << " paused read " << op << " tid " << last_tid << dendl;
     op->paused = true;
     maybe_request_map();
-  } else if ((op->flags & CEPH_OSD_FLAG_WRITE) &&
-            osdmap->test_flag(CEPH_OSDMAP_FULL)) {
+  } else if ((op->flags & CEPH_OSD_FLAG_WRITE) && osdmap_full_flag()) {
     ldout(cct, 0) << " FULL, paused modify " << op << " tid " << last_tid << dendl;
     op->paused = true;
     maybe_request_map();
@@ -1395,12 +1394,24 @@ bool Objecter::is_pg_changed(
 bool Objecter::op_should_be_paused(Op *op)
 {
   bool pauserd = osdmap->test_flag(CEPH_OSDMAP_PAUSERD);
-  bool pausewr = osdmap->test_flag(CEPH_OSDMAP_PAUSEWR) || osdmap->test_flag(CEPH_OSDMAP_FULL);
+  bool pausewr = osdmap->test_flag(CEPH_OSDMAP_PAUSEWR) || osdmap_full_flag();
 
   return (op->flags & CEPH_OSD_FLAG_READ && pauserd) ||
          (op->flags & CEPH_OSD_FLAG_WRITE && pausewr);
 }
 
+
+/**
+ * Wrapper around osdmap->test_flag for special handling of the FULL flag.
+ */
+bool Objecter::osdmap_full_flag() const
+{
+  // Ignore the FULL flag if we are working on behalf of an MDS, in order to permit
+  // MDS journal writes for file deletions.
+  return osdmap->test_flag(CEPH_OSDMAP_FULL) && (messenger->get_myname().type() != entity_name_t::TYPE_MDS);
+}
+
+
 int64_t Objecter::get_object_hash_position(int64_t pool, const string& key,
                                           const string& ns)
 {

diff --git a/src/osdc/Objecter.h b/src/osdc/Objecter.h
index 2311f55ce3676f82313811d04f54239ada4e88f5..df5b5d77e03a3f03baa7f2d1fd807208f6c2efa7 100644 (file)
--- a/src/osdc/Objecter.h
+++ b/src/osdc/Objecter.h
@@ -1463,6 +1463,7 @@ public:
     RECALC_OP_TARGET_OSD_DNE,
     RECALC_OP_TARGET_OSD_DOWN,
   };
+  bool osdmap_full_flag() const;
   bool op_should_be_paused(Op *op);
   int recalc_op_target(Op *op);
   bool recalc_linger_op_target(LingerOp *op);