From d5ca7e9d1e75418290d439d9801e6bc15e2d917a Mon Sep 17 00:00:00 2001
From: Sage Weil <sage@redhat.com>
Date: Thu, 16 Jul 2015 13:14:45 -0400
Subject: [PATCH] osd/osd_types: add last_backfill_bitwise flag to pg_info_t

We need to know what sort order last_backfill is based on.

Signed-off-by: Sage Weil <sage@redhat.com>
---
 src/osd/osd_types.cc | 27 ++++++++++++++++++++++-----
 src/osd/osd_types.h  | 10 +++++++---
 2 files changed, 29 insertions(+), 8 deletions(-)

diff --git a/src/osd/osd_types.cc b/src/osd/osd_types.cc
index df9f5974e7770..f557d3498973a 100644
--- a/src/osd/osd_types.cc
+++ b/src/osd/osd_types.cc
@@ -2374,12 +2374,16 @@ void pg_history_t::generate_test_instances(list<pg_history_t*>& o)
 
 void pg_info_t::encode(bufferlist &bl) const
 {
-  ENCODE_START(30, 26, bl);
+  ENCODE_START(31, 26, bl);
   ::encode(pgid.pgid, bl);
   ::encode(last_update, bl);
   ::encode(last_complete, bl);
   ::encode(log_tail, bl);
-  ::encode(last_backfill, bl);
+  if (last_backfill_bitwise && last_backfill != last_backfill.get_max()) {
+    ::encode(hobject_t(), bl);
+  } else {
+    ::encode(last_backfill, bl);
+  }
   ::encode(stats, bl);
   history.encode(bl);
   ::encode(purged_snaps, bl);
@@ -2387,12 +2391,14 @@ void pg_info_t::encode(bufferlist &bl) const
   ::encode(last_user_version, bl);
   ::encode(hit_set, bl);
   ::encode(pgid.shard, bl);
+  ::encode(last_backfill, bl);
+  ::encode(last_backfill_bitwise, bl);
   ENCODE_FINISH(bl);
 }
 
 void pg_info_t::decode(bufferlist::iterator &bl)
 {
-  DECODE_START_LEGACY_COMPAT_LEN(29, 26, 26, bl);
+  DECODE_START_LEGACY_COMPAT_LEN(31, 26, 26, bl);
   if (struct_v < 23) {
     old_pg_t opgid;
     ::decode(opgid, bl);
@@ -2407,8 +2413,10 @@ void pg_info_t::decode(bufferlist::iterator &bl)
     bool log_backlog;
     ::decode(log_backlog, bl);
   }
-  if (struct_v >= 24)
-    ::decode(last_backfill, bl);
+  hobject_t old_last_backfill;
+  if (struct_v >= 24) {
+    ::decode(old_last_backfill, bl);
+  }
   ::decode(stats, bl);
   history.decode(bl);
   if (struct_v >= 22)
@@ -2432,6 +2440,13 @@ void pg_info_t::decode(bufferlist::iterator &bl)
     ::decode(pgid.shard, bl);
   else
     pgid.shard = shard_id_t::NO_SHARD;
+  if (struct_v >= 31) {
+    ::decode(last_backfill, bl);
+    ::decode(last_backfill_bitwise, bl);
+  } else {
+    last_backfill = old_last_backfill;
+    last_backfill_bitwise = false;
+  }
   DECODE_FINISH(bl);
 }
 
@@ -2445,6 +2460,7 @@ void pg_info_t::dump(Formatter *f) const
   f->dump_stream("log_tail") << log_tail;
   f->dump_int("last_user_version", last_user_version);
   f->dump_stream("last_backfill") << last_backfill;
+  f->dump_int("last_backfill_bitwise", (int)last_backfill_bitwise);
   f->dump_stream("purged_snaps") << purged_snaps;
   f->open_object_section("history");
   history.dump(f);
@@ -2476,6 +2492,7 @@ void pg_info_t::generate_test_instances(list<pg_info_t*>& o)
   o.back()->last_user_version = 2;
   o.back()->log_tail = eversion_t(7, 8);
   o.back()->last_backfill = hobject_t(object_t("objname"), "key", 123, 456, -1, "");
+  o.back()->last_backfill_bitwise = true;
   {
     list<pg_stat_t*> s;
     pg_stat_t::generate_test_instances(s);
diff --git a/src/osd/osd_types.h b/src/osd/osd_types.h
index 4d4579a4dd39b..737817319362f 100644
--- a/src/osd/osd_types.h
+++ b/src/osd/osd_types.h
@@ -1835,6 +1835,7 @@ struct pg_info_t {
   eversion_t log_tail;     // oldest log entry.
 
   hobject_t last_backfill;   // objects >= this and < last_complete may be missing
+  bool last_backfill_bitwise;  ///< true if last_backfill reflects a bitwise (vs nibblewise) sort
 
   interval_set<snapid_t> purged_snaps;
 
@@ -1845,12 +1846,14 @@ struct pg_info_t {
 
   pg_info_t()
     : last_epoch_started(0), last_user_version(0),
-      last_backfill(hobject_t::get_max())
+      last_backfill(hobject_t::get_max()),
+      last_backfill_bitwise(false)
   { }
   pg_info_t(spg_t p)
     : pgid(p),
       last_epoch_started(0), last_user_version(0),
-      last_backfill(hobject_t::get_max())
+      last_backfill(hobject_t::get_max()),
+      last_backfill_bitwise(false)
   { }
   
   bool is_empty() const { return last_update.version == 0; }
@@ -1884,7 +1887,8 @@ inline ostream& operator<<(ostream& out, const pg_info_t& pgi)
     out << " (" << pgi.log_tail << "," << pgi.last_update << "]";
   }
   if (pgi.is_incomplete())
-    out << " lb " << pgi.last_backfill;
+    out << " lb " << pgi.last_backfill
+	<< (pgi.last_backfill_bitwise ? " (bitwise)" : " (NIBBLEWISE)");
   //out << " c " << pgi.epoch_created;
   out << " local-les=" << pgi.last_epoch_started;
   out << " n=" << pgi.stats.stats.sum.num_objects;
-- 
2.39.5