From 1419f0021827f374abf449ae68e4fd6fda421cd0 Mon Sep 17 00:00:00 2001
From: Sage Weil <sage@newdream.net>
Date: Tue, 23 Dec 2008 12:29:04 -0800
Subject: [PATCH] os: start_sync osd operation

If a client has a time sensitive operation, it can include a start_sync
in the op vector to start an immediate commit to disk.  It should then
get the ONDISK ack sooner.
---
 src/ebofs/Ebofs.cc      |  5 +++++
 src/include/ceph_fs.h   |  1 +
 src/os/FileStore.cc     | 10 ++++++++++
 src/os/FileStore.h      |  2 ++
 src/os/ObjectStore.h    |  7 +++++++
 src/osd/ReplicatedPG.cc |  3 +++
 6 files changed, 28 insertions(+)

diff --git a/src/ebofs/Ebofs.cc b/src/ebofs/Ebofs.cc
index da753a710a9f8..17d34f34aa2ac 100644
--- a/src/ebofs/Ebofs.cc
+++ b/src/ebofs/Ebofs.cc
@@ -2493,6 +2493,11 @@ unsigned Ebofs::_apply_transaction(Transaction& t)
     int op = t.get_op();
     switch (op) {
  
+    case Transaction::OP_STARTSYNC:
+      dirty = true;
+      commit_cond.Signal();
+      break;
+
     case Transaction::OP_TOUCH:
       {
 	coll_t cid = t.get_cid();
diff --git a/src/include/ceph_fs.h b/src/include/ceph_fs.h
index e2190f6e2a8f2..ed96845754077 100644
--- a/src/include/ceph_fs.h
+++ b/src/include/ceph_fs.h
@@ -1112,6 +1112,7 @@ enum {
 
 	/* fancy write */
 	CEPH_OSD_OP_APPEND     = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_DATA | 6,
+	CEPH_OSD_OP_STARTSYNC  = CEPH_OSD_OP_MODE_WR | CEPH_OSD_OP_TYPE_DATA | 7,
 };
 
 static inline int ceph_osd_op_type_lock(int op)
diff --git a/src/os/FileStore.cc b/src/os/FileStore.cc
index bdc3a850f25b1..c5e46e7100563 100644
--- a/src/os/FileStore.cc
+++ b/src/os/FileStore.cc
@@ -694,6 +694,10 @@ unsigned FileStore::_apply_transaction(Transaction& t)
       _collection_rmattr(t.get_cid(), t.get_attrname());
       break;
 
+    case Transaction::OP_STARTSYNC:
+      _start_sync();
+      break;
+
     default:
       cerr << "bad op " << op << std::endl;
       assert(0);
@@ -1431,6 +1435,12 @@ void FileStore::sync_entry()
   lock.Unlock();
 }
 
+void FileStore::_start_sync()
+{
+  dout(10) << "start_sync" << dendl;
+  sync_cond.Signal();
+}
+
 void FileStore::sync()
 {
   Mutex::Locker l(lock);
diff --git a/src/os/FileStore.h b/src/os/FileStore.h
index 9f6fabc136902..69ede33204bca 100644
--- a/src/os/FileStore.h
+++ b/src/os/FileStore.h
@@ -115,6 +115,8 @@ class FileStore : public JournalingObjectStore {
   int _do_clone_range(int from, int to, __u64 off, __u64 len);
   int _remove(coll_t cid, pobject_t oid);
 
+  void _start_sync();
+
   void sync();
   void sync(Context *onsafe);
 
diff --git a/src/os/ObjectStore.h b/src/os/ObjectStore.h
index 3877d50aec2e2..ac077d449fda3 100644
--- a/src/os/ObjectStore.h
+++ b/src/os/ObjectStore.h
@@ -98,6 +98,9 @@ public:
     static const int OP_COLL_RMATTR =  25;  // cid, attrname
     static const int OP_COLL_SETATTRS = 26;  // cid, attrset
 
+    static const int OP_STARTSYNC =    27;  // start a sync 
+
+
   private:
     /*
     int len;
@@ -158,6 +161,10 @@ public:
       return attrsets[attrsetp++];
     }
 
+    void start_sync() {
+      int op = OP_STARTSYNC;
+      ops.push_back(op);
+    }
     void touch(coll_t cid, pobject_t oid) {
       int op = OP_TOUCH;
       ops.push_back(op);
diff --git a/src/osd/ReplicatedPG.cc b/src/osd/ReplicatedPG.cc
index 46f519f2156dc..dbb4777dc3916 100644
--- a/src/osd/ReplicatedPG.cc
+++ b/src/osd/ReplicatedPG.cc
@@ -1131,6 +1131,9 @@ int ReplicatedPG::prepare_simple_op(ObjectStore::Transaction& t, osd_reqid_t req
     }
     break;
 
+  case CEPH_OSD_OP_STARTSYNC:
+    t.start_sync();
+    break;
 
   default:
     return -EINVAL;
-- 
2.47.3