From f39d0a1d0db5e7ae8f74b51e6fc80c25916cf6e5 Mon Sep 17 00:00:00 2001
From: Kefu Chai <kchai@redhat.com>
Date: Wed, 26 Aug 2020 21:46:06 +0800
Subject: [PATCH] crimson/osd: extract load_obc_for_recovery() out

extract ReplicatedRecoveryBackend::load_obc_for_recovery()
from ReplicatedRecoveryBackend::recover_object() for better readability

Signed-off-by: Kefu Chai <kchai@redhat.com>
---
 .../osd/replicated_recovery_backend.cc        | 84 ++++++++++---------
 src/crimson/osd/replicated_recovery_backend.h |  6 ++
 2 files changed, 50 insertions(+), 40 deletions(-)

diff --git a/src/crimson/osd/replicated_recovery_backend.cc b/src/crimson/osd/replicated_recovery_backend.cc
index a308bed8548f9..6013564b60380 100644
--- a/src/crimson/osd/replicated_recovery_backend.cc
+++ b/src/crimson/osd/replicated_recovery_backend.cc
@@ -26,46 +26,10 @@ seastar::future<> ReplicatedRecoveryBackend::recover_object(
   auto& recovery_waiter = recovering[soid];
   return seastar::do_with(std::map<pg_shard_t, PushOp>(), get_shards_to_push(soid),
     [this, soid, need](auto& pops, auto& shards) {
-    return maybe_pull_missing_obj(soid, need).then(
-      [this, &pops, &shards, soid, need, &recovery_waiter](bool pulled) mutable {
-      return [this, &recovery_waiter, soid, pulled] {
-	if (!recovery_waiter.obc) {
-	  return pg.get_or_load_head_obc(soid).safe_then(
-	    [&recovery_waiter, pulled](auto p) {
-	    auto& [obc, existed] = p;
-	    logger().debug("recover_object: loaded obc: {}", obc->obs.oi.soid);
-	    recovery_waiter.obc = obc;
-	    if (!existed) {
-	      // obc is loaded with excl lock
-	      recovery_waiter.obc->put_lock_type(RWState::RWEXCL);
-	    }
-	    bool got = recovery_waiter.obc->get_recovery_read().get0();
-	    ceph_assert_always(pulled ? got : 1);
-	    if (!got) {
-	      return recovery_waiter.obc->get_recovery_read(true)
-	      .then([](bool) { return seastar::now(); });
-	    }
-	    return seastar::make_ready_future<>();
-	  }, crimson::osd::PG::load_obc_ertr::all_same_way(
-	      [this, &recovery_waiter, soid](const std::error_code& e) {
-	      auto [obc, existed] =
-		  shard_services.obc_registry.get_cached_obc(soid);
-	      logger().debug("recover_object: load failure of obc: {}",
-		  obc->obs.oi.soid);
-	      recovery_waiter.obc = obc;
-	      // obc is loaded with excl lock
-	      recovery_waiter.obc->put_lock_type(RWState::RWEXCL);
-	      ceph_assert_always(recovery_waiter.obc->get_recovery_read().get0());
-	      return seastar::make_ready_future<>();
-	    })
-	  );
-	} else {
-	  logger().debug("recover_object: already has obc!");
-	}
-	return seastar::now();
-      }().then([this, soid, need, &pops, &shards] {
-	return prep_push(soid, need, &pops, shards);
-      });
+    return maybe_pull_missing_obj(soid, need).then([this, soid](bool pulled) {
+      return load_obc_for_recovery(soid, pulled);
+    }).then([this, soid, need, &pops, &shards] {
+      return prep_push(soid, need, &pops, shards);
     }).handle_exception([this, soid](auto e) {
       auto& recovery_waiter = recovering[soid];
       if (recovery_waiter.obc)
@@ -147,6 +111,46 @@ ReplicatedRecoveryBackend::maybe_pull_missing_obj(
   });
 }
 
+seastar::future<> ReplicatedRecoveryBackend::load_obc_for_recovery(
+  const hobject_t& soid,
+  bool pulled)
+{
+  auto& recovery_waiter = recovering[soid];
+  if (recovery_waiter.obc) {
+    return seastar::now();
+  }
+  return pg.get_or_load_head_obc(soid).safe_then(
+    [&recovery_waiter, pulled](auto p) {
+    auto& [obc, existed] = p;
+    logger().debug("load_obc_for_recovery: loaded obc: {}", obc->obs.oi.soid);
+    recovery_waiter.obc = obc;
+    if (!existed) {
+      // obc is loaded with excl lock
+      recovery_waiter.obc->put_lock_type(RWState::RWEXCL);
+    }
+    bool got = recovery_waiter.obc->get_recovery_read().get0();
+    ceph_assert_always(pulled ? got : 1);
+    if (got) {
+      return seastar::make_ready_future<>();
+    }
+    return recovery_waiter.obc->get_recovery_read(true).then([](bool) {
+      return seastar::now();
+    });
+  }, crimson::osd::PG::load_obc_ertr::all_same_way(
+      [this, &recovery_waiter, soid](const std::error_code& e) {
+      auto [obc, existed] =
+	  shard_services.obc_registry.get_cached_obc(soid);
+      logger().debug("load_obc_for_recovery: load failure of obc: {}",
+	  obc->obs.oi.soid);
+      recovery_waiter.obc = obc;
+      // obc is loaded with excl lock
+      recovery_waiter.obc->put_lock_type(RWState::RWEXCL);
+      ceph_assert_always(recovery_waiter.obc->get_recovery_read().get0());
+      return seastar::make_ready_future<>();
+    })
+  );
+}
+
 seastar::future<> ReplicatedRecoveryBackend::push_delete(
   const hobject_t& soid,
   eversion_t need)
diff --git a/src/crimson/osd/replicated_recovery_backend.h b/src/crimson/osd/replicated_recovery_backend.h
index 667cd9876321e..a224cb6da3e3b 100644
--- a/src/crimson/osd/replicated_recovery_backend.h
+++ b/src/crimson/osd/replicated_recovery_backend.h
@@ -115,6 +115,12 @@ private:
   seastar::future<bool> maybe_pull_missing_obj(
     const hobject_t& soid,
     eversion_t need);
+
+  /// load object context for recovery if it is not ready yet
+  seastar::future<> load_obc_for_recovery(
+    const hobject_t& soid,
+    bool pulled);
+
   /// read the remaining extents of object to be recovered and fill push_op
   /// with them
   ///
-- 
2.39.5