SERVER-17817 Make ServiceContext create and manage Client objects.

Also, deduplicate Client::* method implementations, guard the identity of the
current CurOp of a Client with the Client's _mutex instead of the mutex guarding
the list of all clients.

Makes the currentClient object private to client.cpp, and all access to the
thread-bound client is now done with haveClient() and cc() free functions in the
mongo namespace.

Removes the vesitgal Client::shutdown() methods.

2 files changed, 16 insertions, 27 deletions

diff --git a/src/mongo/db/stats/lock_server_status_section.cpp b/src/mongo/db/stats/lock_server_status_section.cpp
index 1e81904b158..7b1350af9c0 100644
--- a/src/mongo/db/stats/lock_server_status_section.cpp
+++ b/src/mongo/db/stats/lock_server_status_section.cpp
@@ -55,35 +55,28 @@ namespace {
             int numWaitingWrite = 0;
 
             // This returns the blocked lock states
-            {
-                boost::lock_guard<boost::mutex> scopedLock(Client::clientsMutex);
-
-                // Count all clients
-                numTotal = Client::clients.size();
+            for (ServiceContext::LockedClientsCursor cursor(txn->getClient()->getServiceContext());
+                 Client* client = cursor.next();) {
 
-                ClientSet::const_iterator it = Client::clients.begin();
-                for (; it != Client::clients.end(); it++) {
-                    Client* client = *it;
-                    invariant(client);
+                invariant(client);
+                ++numTotal;
+                boost::unique_lock<Client> uniqueLock(*client);
 
-                    boost::unique_lock<Client> uniqueLock(*client);
+                const OperationContext* opCtx = client->getOperationContext();
+                if (opCtx == NULL) continue;
 
-                    const OperationContext* opCtx = client->getOperationContext();
-                    if (opCtx == NULL) continue;
+                if (opCtx->lockState()->isWriteLocked()) {
+                    numWriteLocked++;
 
-                    if (opCtx->lockState()->isWriteLocked()) {
-                        numWriteLocked++;
-
-                        if (opCtx->lockState()->getWaitingResource().isValid()) {
-                            numWaitingWrite++;
-                        }
+                    if (opCtx->lockState()->getWaitingResource().isValid()) {
+                        numWaitingWrite++;
                     }
-                    else if (opCtx->lockState()->isReadLocked()) {
-                        numReadLocked++;
+                }
+                else if (opCtx->lockState()->isReadLocked()) {
+                    numReadLocked++;
 
-                        if (opCtx->lockState()->getWaitingResource().isValid()) {
-                            numWaitingRead++;
-                        }
+                    if (opCtx->lockState()->getWaitingResource().isValid()) {
+                        numWaitingRead++;
                     }
                 }
             }
diff --git a/src/mongo/db/stats/snapshots.cpp b/src/mongo/db/stats/snapshots.cpp
index addf361bcb6..2e2d2f9398f 100644
--- a/src/mongo/db/stats/snapshots.cpp
+++ b/src/mongo/db/stats/snapshots.cpp
@@ -109,8 +109,6 @@ namespace mongo {
 
     void SnapshotThread::run() {
         Client::initThread("snapshot");
-        Client& client = cc();
-
         while ( ! inShutdown() ) {
             try {
                 statsSnapshots.takeSnapshot();
@@ -121,8 +119,6 @@ namespace mongo {
 
             sleepsecs(4);
         }
-
-        client.shutdown();
     }
 
     Snapshots statsSnapshots;