From 41db5d164fe6fcd7e9454af8713e6e3643b3ebfa Mon Sep 17 00:00:00 2001
From: Xuehan Xu <xxhdx1985126@163.com>
Date: Mon, 8 Jun 2020 14:41:54 +0800
Subject: [PATCH] crimson/osd: share map with clients when osdmap epoch doesn't
 match

Signed-off-by: Xuehan Xu <xxhdx1985126@163.com>
---
 src/crimson/osd/osd.cc                        | 45 +++++++++++++++++++
 src/crimson/osd/osd.h                         |  5 +++
 .../osd/osd_operations/client_request.cc      |  5 +++
 3 files changed, 55 insertions(+)

diff --git a/src/crimson/osd/osd.cc b/src/crimson/osd/osd.cc
index 0bf20f0f2b3..62a02c84457 100644
--- a/src/crimson/osd/osd.cc
+++ b/src/crimson/osd/osd.cc
@@ -735,6 +735,25 @@ seastar::future<bufferlist> OSD::load_map_bl(epoch_t e)
   }
 }
 
+seastar::future<std::map<epoch_t, bufferlist>> OSD::load_map_bls(
+  epoch_t first,
+  epoch_t last)
+{
+  return seastar::map_reduce(boost::make_counting_iterator<epoch_t>(first),
+			     boost::make_counting_iterator<epoch_t>(last + 1),
+			     [this](epoch_t e) {
+    return load_map_bl(e).then([e](auto&& bl) {
+	return seastar::make_ready_future<pair<epoch_t, bufferlist>>(
+	    std::make_pair(e, std::move(bl)));
+    });
+  },
+  std::map<epoch_t, bufferlist>{},
+  [](auto&& bls, auto&& epoch_bl) {
+    bls.emplace(std::move(epoch_bl));
+    return std::move(bls);
+  });
+}
+
 seastar::future<std::unique_ptr<OSDMap>> OSD::load_map(epoch_t e)
 {
   auto o = std::make_unique<OSDMap>();
@@ -1023,6 +1042,32 @@ seastar::future<> OSD::handle_osd_op(crimson::net::Connection* conn,
   return seastar::now();
 }
 
+seastar::future<> OSD::send_incremental_map(crimson::net::Connection* conn,
+					    epoch_t first)
+{
+  if (first >= superblock.oldest_map) {
+    return load_map_bls(first, superblock.newest_map)
+    .then([this, conn, first](auto&& bls) {
+      auto m = make_message<MOSDMap>(monc->get_fsid(),
+	  osdmap->get_encoding_features());
+      m->oldest_map = first;
+      m->newest_map = superblock.newest_map;
+      m->maps = std::move(bls);
+      return conn->send(m);
+    });
+  } else {
+    return load_map_bl(osdmap->get_epoch())
+    .then([this, conn, first](auto&& bl) mutable {
+      auto m = make_message<MOSDMap>(monc->get_fsid(),
+	  osdmap->get_encoding_features());
+      m->oldest_map = superblock.oldest_map;
+      m->newest_map = superblock.newest_map;
+      m->maps.emplace(osdmap->get_epoch(), std::move(bl));
+      return conn->send(m);
+    });
+  }
+}
+
 seastar::future<> OSD::handle_rep_op(crimson::net::Connection* conn,
 				     Ref<MOSDRepOp> m)
 {
diff --git a/src/crimson/osd/osd.h b/src/crimson/osd/osd.h
index cb6c0db3b04..18197aa8cd7 100644
--- a/src/crimson/osd/osd.h
+++ b/src/crimson/osd/osd.h
@@ -132,6 +132,9 @@ public:
   void dump_status(Formatter*) const;
 
   void print(std::ostream&) const;
+
+  seastar::future<> send_incremental_map(crimson::net::Connection* conn,
+					 epoch_t first);
 private:
   seastar::future<> start_boot();
   seastar::future<> _preboot(version_t oldest_osdmap, version_t newest_osdmap);
@@ -155,6 +158,8 @@ private:
   cached_map_t get_map() const final;
   seastar::future<std::unique_ptr<OSDMap>> load_map(epoch_t e);
   seastar::future<bufferlist> load_map_bl(epoch_t e);
+  seastar::future<std::map<epoch_t, bufferlist>>
+  load_map_bls(epoch_t first, epoch_t last);
   void store_map_bl(ceph::os::Transaction& t,
                     epoch_t e, bufferlist&& bl);
   seastar::future<> store_maps(ceph::os::Transaction& t,
diff --git a/src/crimson/osd/osd_operations/client_request.cc b/src/crimson/osd/osd_operations/client_request.cc
index 142a2f0af06..0d7123181fb 100644
--- a/src/crimson/osd/osd_operations/client_request.cc
+++ b/src/crimson/osd/osd_operations/client_request.cc
@@ -69,6 +69,11 @@ seastar::future<> ClientRequest::start()
 	return with_blocking_future(osd.wait_for_pg(m->get_spg()));
       }).then([this, opref](Ref<PG> pgref) {
 	PG &pg = *pgref;
+	if (__builtin_expect(m->get_map_epoch()
+			      < pg.get_info().history.same_primary_since,
+			     false)) {
+	  return osd.send_incremental_map(conn.get(), m->get_map_epoch());
+	}
 	return with_blocking_future(
 	  handle.enter(pp(pg).await_map)
 	).then([this, &pg]() mutable {
-- 
2.39.5