From: Samuel Just <sjust@redhat.com>
Date: Thu, 19 May 2016 23:00:35 +0000 (-0700)
Subject: PG: update PGPool to detect map gaps and reset cached_removed_snaps
X-Git-Tag: v10.2.3~138^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=b7f0e73223687035e470fcd7ffc7b851c04aba00;p=ceph.git

PG: update PGPool to detect map gaps and reset cached_removed_snaps

Fixes: http://tracker.ceph.com/issues/15943
Signed-off-by: Samuel Just <sjust@redhat.com>
(cherry picked from commit 5798fb3bf6d726d14a9c5cb99dc5902eba5b878a)
---

diff --git a/src/osd/OSD.cc b/src/osd/OSD.cc
index 6d01fe8d6773..23d167591e8b 100644
--- a/src/osd/OSD.cc
+++ b/src/osd/OSD.cc
@@ -2885,14 +2885,8 @@ PGPool OSD::_get_pool(int id, OSDMapRef createmap)
     assert(0);
   }
 
-  PGPool p = PGPool(id, createmap->get_pool_name(id),
-		    createmap->get_pg_pool(id)->auid);
+  PGPool p = PGPool(createmap, id);
 
-  const pg_pool_t *pi = createmap->get_pg_pool(id);
-  p.info = *pi;
-  p.snapc = pi->get_snap_context();
-
-  pi->build_removed_snaps(p.cached_removed_snaps);
   dout(10) << "_get_pool " << p.id << dendl;
   return p;
 }
diff --git a/src/osd/PG.cc b/src/osd/PG.cc
index e7e644298bd3..37737172a4cb 100644
--- a/src/osd/PG.cc
+++ b/src/osd/PG.cc
@@ -157,7 +157,10 @@ void PGPool::update(OSDMapRef map)
   info = *pi;
   auid = pi->auid;
   name = map->get_pool_name(id);
-  if (pi->get_snap_epoch() == map->get_epoch()) {
+  bool updated = false;
+  if ((map->get_epoch() == cached_epoch + 1) &&
+      (pi->get_snap_epoch() == map->get_epoch())) {
+    updated = true;
     pi->build_removed_snaps(newly_removed_snaps);
     interval_set<snapid_t> intersection;
     intersection.intersection_of(newly_removed_snaps, cached_removed_snaps);
@@ -175,14 +178,14 @@ void PGPool::update(OSDMapRef map)
   } else {
     newly_removed_snaps.clear();
   }
+  cached_epoch = map->get_epoch();
   lgeneric_subdout(g_ceph_context, osd, 20)
     << "PGPool::update cached_removed_snaps "
     << cached_removed_snaps
     << " newly_removed_snaps "
     << newly_removed_snaps
     << " snapc " << snapc
-    << (pi->get_snap_epoch() == map->get_epoch() ?
-	" (updated)":" (no change)")
+    << (updated ? " (updated)":" (no change)")
     << dendl;
 }
 
diff --git a/src/osd/PG.h b/src/osd/PG.h
index 50a8d72f06fa..925e8bd87c9c 100644
--- a/src/osd/PG.h
+++ b/src/osd/PG.h
@@ -165,6 +165,7 @@ struct PGRecoveryStats {
 };
 
 struct PGPool {
+  epoch_t cached_epoch;
   int64_t id;
   string name;
   uint64_t auid;
@@ -175,8 +176,17 @@ struct PGPool {
   interval_set<snapid_t> cached_removed_snaps;      // current removed_snaps set
   interval_set<snapid_t> newly_removed_snaps;  // newly removed in the last epoch
 
-  PGPool(int64_t i, const string& _name, uint64_t au)
-    : id(i), name(_name), auid(au) { }
+  PGPool(OSDMapRef map, int64_t i)
+    : cached_epoch(map->get_epoch()),
+      id(i),
+      name(map->get_pool_name(id)),
+      auid(map->get_pg_pool(id)->auid) {
+    const pg_pool_t *pi = map->get_pg_pool(id);
+    assert(pi);
+    info = *pi;
+    snapc = pi->get_snap_context();
+    pi->build_removed_snaps(cached_removed_snaps);
+  }
 
   void update(OSDMapRef map);
 };