osd: pick_read_snap v1

diff --git a/src/include/types.h b/src/include/types.h
index 6864e022b89e54e4d8b362d9bb37496f6a91c624..fa61afb53da5d15418dab00cc8a1dcf040827957 100644 (file)
--- a/src/include/types.h
+++ b/src/include/types.h
@@ -321,7 +321,17 @@ struct SnapContext {
     snaps.clear();
   }
   bool empty() { return seq == 0; }
+
+  void encode(bufferlist& bl) const {
+    ::encode(seq, bl);
+    ::encode(snaps, bl);
+  }
+  void decode(bufferlist::iterator& bl) {
+    ::decode(seq, bl);
+    ::decode(snaps, bl);
+  }
 };
+WRITE_CLASS_ENCODER(SnapContext)
 
 inline ostream& operator<<(ostream& out, const SnapContext& snapc) {
   return out << snapc.seq << "=" << snapc.snaps;

diff --git a/src/osd/PG.cc b/src/osd/PG.cc
index d04343fcfdc2bcd7dc0a95240ac0f681961c7baa..36dec0be3935587e748fd9ee639f6604e4be9627 100644 (file)
--- a/src/osd/PG.cc
+++ b/src/osd/PG.cc
@@ -1360,97 +1360,3 @@ bool PG::block_if_wrlocked(MOSDOp* op)
 
 
 
-
-// =======================
-// revisions
-
-
-/*
-int OSD::list_missing_revs(object_t oid, set<object_t>& revs, PG *pg)
-{
-  int c = 0;
-  oid.rev = 0;
-  
-  map<object_t,eversion_t>::iterator p = pg->missing.missing.lower_bound(oid);
-  if (p == pg->missing.missing.end()) 
-    return 0;  // clearly not
-
-  while (p->first.ino == oid.ino &&
-        p->first.bno == oid.bno) {
-    revs.insert(p->first);
-    c++;
-  }
-  return c;
-}*/
-
-/*
-bool PG::pick_missing_object_rev(object_t& oid)
-{
-  map<object_t,eversion_t>::iterator p = missing.missing.upper_bound(oid);
-  if (p == missing.missing.end()) 
-    return false;  // clearly no candidate
-
-  if (p->first.ino == oid.ino && p->first.bno == oid.bno) {
-    oid = p->first;  // yes!  it's an upper bound revision for me.
-    return true;
-  }
-  return false;
-}
-
-*/
-
-
-bool PG::pick_object_rev(pobject_t& poid, vector<snapid_t> &snapvec)
-{
-  pobject_t t = poid;
-  vector<snapid_t> csnap(1);
-  int r;
-
-  dout(10) << "pick_object_rev " << poid << " snapvec " << snapvec << dendl;
-  snapid_t want = poid.oid.snap;
-
-  for (int i=-1; i<(int)snapvec.size(); i++) {
-    snapid_t last;
-    if (i < 0)
-      last = t.oid.snap = CEPH_NOSNAP;
-    else
-      last = t.oid.snap = snapvec[i];
-    if (last < want) {
-      dout(20) << "pick_object_rev  stopping at clone " << t << ": last " << last << " < want " << want << dendl;
-      return false;
-    }
-    
-    if (last == CEPH_NOSNAP) {
-      csnap.resize(1);
-      csnap[0] = NOSNAP;
-    } else {
-      r = osd->store->getattr(info.pgid, t, "snaps", &csnap[0], 0);
-      if (r == -ENOENT) {
-       dout(20) << "pick_object_rev  " << t << " dne" << dendl;
-       continue;
-      }
-
-      csnap.resize(r / sizeof(csnap[0]));
-      int r2 = osd->store->getattr(info.pgid, t, "snaps", &csnap[0], r);
-      assert(r == r2);
-    }
-
-    snapid_t first = csnap[csnap.size()-1];
-    dout(20) << "pick_object_rev ? " << t << " [" << first << "," << last << "] csnap " << csnap << dendl;
-    assert(csnap[0] == last);
-
-    if (first <= want) {
-      dout(20) << "pick_object_rev  " << t << " first " << first << " <= " << poid.oid.snap << " -- HIT" << dendl;
-      poid = t;
-      return true;
-    }
-
-    dout(20) << "pick_object_rev  skipping clone " << t << ": first " << first << " > want " << want << dendl;
-    while (i+1 < (int)snapvec.size() &&
-          snapvec[i+1] > first) {
-      i++;
-      dout(20) << "pick_object_rev    and snap " << snapvec[i] << dendl;
-    }
-  }
-  return false;
-}

diff --git a/src/osd/PG.h b/src/osd/PG.h
index 3190aab1a13021c37831969b0f529c285be6bd1e..ebe4446ab991d6179554e31b0efc4fc57865bddc 100644 (file)
--- a/src/osd/PG.h
+++ b/src/osd/PG.h
@@ -685,9 +685,6 @@ public:
   }
 
 
-  bool pick_object_rev(pobject_t& oid, vector<snapid_t> &spanvec);
-
-
 
   // abstract bits
   virtual bool preprocess_op(MOSDOp *op, utime_t now) { return false; } 

diff --git a/src/osd/ReplicatedPG.cc b/src/osd/ReplicatedPG.cc
index 0e6bd839b4a514ff6e69eb57b8d49cecad8cd2b9..13c5c7ffd47d870cfc299aa09e6d2781675bf1fb 100644 (file)
--- a/src/osd/ReplicatedPG.cc
+++ b/src/osd/ReplicatedPG.cc
@@ -448,6 +448,83 @@ void ReplicatedPG::do_sub_op_reply(MOSDSubOpReply *r)
 // ========================================================================
 // READS
 
+
+/*
+ * return false if object doesn't (logically) exist
+ */
+bool ReplicatedPG::pick_read_snap(pobject_t& poid)
+{
+  pobject_t head = poid;
+  head.oid.snap = CEPH_NOSNAP;
+
+  bufferptr bp;
+  int r = osd->store->getattr(info.pgid, head, "snapc", bp);
+  if (r < 0)
+    return false;  // if head doesn't exist, no snapped version will either.
+  bufferlist bl;
+  bl.push_back(bp);
+  bufferlist::iterator p = bl.begin();
+  SnapContext snapc;
+  ::decode(snapc, p);
+
+  dout(10) << "pick_read_snap " << poid << " snapc " << snapc << dendl;
+  snapid_t want = poid.oid.snap;
+  vector<snapid_t> csnap;
+  pobject_t t = poid;
+
+  for (int i=-1; i<(int)snapc.snaps.size(); i++) {
+    snapid_t last;
+    if (i < 0)
+      last = t.oid.snap = CEPH_NOSNAP;
+    else
+      last = t.oid.snap = snapc.snaps[i];
+    if (last < want) {
+      dout(20) << "pick_read_snap  stopping (DNE) at clone " << t
+              << ": last " << last << " < want " << want << dendl;
+      return false;
+    }
+    
+    if (last == CEPH_NOSNAP) {
+      csnap.resize(1);
+      csnap[0] = CEPH_NOSNAP;
+    } else {
+      bufferptr bp;
+      r = osd->store->getattr(info.pgid, t, "snaps", bp);
+      if (r < 0) {
+       dout(20) << "pick_read_snap  " << t << " dne" << dendl;
+       continue;
+      }
+      bufferlist bl;
+      bl.push_back(bp);
+      bufferlist::iterator p = bl.begin();
+      ::decode(csnap, p);
+      dout(20) << "pick_read_snap  " << t << " snaps " << csnap << dendl;
+    }
+    
+    snapid_t first = csnap[csnap.size()-1];
+    dout(20) << "pick_read_snap ? " << t << " [" << first << "," << last
+            << "] csnap " << csnap << dendl;
+    assert(csnap[0] == last);
+
+    if (first <= want) {
+      dout(20) << "pick_read_snap  " << t << " first " << first << " <= " << poid.oid.snap
+              << " -- HIT" << dendl;
+      poid = t;
+      return true;
+    }
+
+    dout(20) << "pick_read_snap  skipping clone " << t
+            << ": first " << first << " > want " << want << dendl;
+    while (i+1 < (int)snapc.snaps.size() &&
+          snapc.snaps[i+1] > first) {
+      i++;
+      dout(20) << "pick_read_snap    and snap " << snapc.snaps[i] << dendl;
+    }
+  }
+  return false;
+}
+
+
 void ReplicatedPG::op_read(MOSDOp *op)
 {
   object_t oid = op->get_oid();
@@ -510,7 +587,7 @@ void ReplicatedPG::op_read(MOSDOp *op)
   long r = 0;
 
   // do it.
-  if (poid.oid.snap && !pick_object_rev(poid, op->get_snaps())) {
+  if (poid.oid.snap && !pick_read_snap(poid)) {
     // we have no revision for this request.
     r = -EEXIST;
     goto done;

diff --git a/src/osd/ReplicatedPG.h b/src/osd/ReplicatedPG.h
index 8a093609c5e486ae58ee281c7883fc5f8532098a..9b2a7f426a02ed773dc7abd833d1f0021165537c 100644 (file)
--- a/src/osd/ReplicatedPG.h
+++ b/src/osd/ReplicatedPG.h
@@ -120,7 +120,7 @@ protected:
   bool do_recovery();
   void do_peer_recovery();
 
-
+  bool pick_read_snap(pobject_t& poid);
   void op_read(MOSDOp *op);
   void op_modify(MOSDOp *op);