From: Josh Durgin <josh.durgin@inktank.com>
Date: Sun, 12 May 2013 21:45:36 +0000 (-0700)
Subject: librados: add per-ObjectOperation flags for balanced and localized reads
X-Git-Tag: v0.63~38^2~2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=4ddaea70b2d10d4544bd05a59400b2c2fc275179;p=ceph.git

librados: add per-ObjectOperation flags for balanced and localized reads

These need to apply to the entire ObjectOperation, not just a subop,
so use a new enum and a new aio_operate() call that takes them.

Signed-off-by: Josh Durgin <josh.durgin@inktank.com>
---

diff --git a/src/include/rados/librados.hpp b/src/include/rados/librados.hpp
index 0f09f3f13933..af14a183b493 100644
--- a/src/include/rados/librados.hpp
+++ b/src/include/rados/librados.hpp
@@ -105,11 +105,28 @@ namespace librados
     PoolAsyncCompletionImpl *pc;
   };
 
+  /**
+   * These are per-op flags which may be different among
+   * ops added to an ObjectOperation.
+   */
   enum ObjectOperationFlags {
     OP_EXCL =   1,
     OP_FAILOK = 2,
   };
 
+  /**
+   * These flags apply to the ObjectOperation as a whole.
+   *
+   * BALANCE_READS and LOCALIZE_READS should only be used
+   * when reading from data you're certain won't change,
+   * like a snapshot, or where eventual consistency is ok.
+   */
+  enum ObjectOperationGlobalFlags {
+    OPERATION_NOFLAG         = 0,
+    OPERATION_BALANCE_READS  = 1,
+    OPERATION_LOCALIZE_READS = 2,
+  };
+
   /*
    * ObjectOperation : compound object operation
    * Batch multiple object operations into a single request, to be applied
@@ -586,7 +603,10 @@ namespace librados
     int aio_operate(const std::string& oid, AioCompletion *c,
 		    ObjectWriteOperation *op, snap_t seq,
 		    std::vector<snap_t>& snaps);
-    int aio_operate(const std::string& oid, AioCompletion *c, ObjectReadOperation *op,
+    int aio_operate(const std::string& oid, AioCompletion *c,
+		    ObjectReadOperation *op, bufferlist *pbl);
+    int aio_operate(const std::string& oid, AioCompletion *c,
+		    ObjectReadOperation *op, snap_t snapid, int flags,
 		    bufferlist *pbl);
 
     // watch/notify
diff --git a/src/librados/IoCtxImpl.cc b/src/librados/IoCtxImpl.cc
index d64eeea2dca8..abeda88d018e 100644
--- a/src/librados/IoCtxImpl.cc
+++ b/src/librados/IoCtxImpl.cc
@@ -695,7 +695,9 @@ int librados::IoCtxImpl::operate_read(const object_t& oid,
 
 int librados::IoCtxImpl::aio_operate_read(const object_t &oid,
 					  ::ObjectOperation *o,
-					  AioCompletionImpl *c, bufferlist *pbl)
+					  AioCompletionImpl *c,
+					  int flags,
+					  bufferlist *pbl)
 {
   Context *onack = new C_aio_Ack(c);
 
@@ -705,7 +707,7 @@ int librados::IoCtxImpl::aio_operate_read(const object_t &oid,
 
   Mutex::Locker l(*lock);
   objecter->read(oid, oloc,
-		 *o, snap_seq, pbl, 0,
+		 *o, snap_seq, pbl, flags,
 		 onack, &c->objver);
   return 0;
 }
diff --git a/src/librados/IoCtxImpl.h b/src/librados/IoCtxImpl.h
index 538c2f1d357a..7e589a82f505 100644
--- a/src/librados/IoCtxImpl.h
+++ b/src/librados/IoCtxImpl.h
@@ -140,7 +140,8 @@ struct librados::IoCtxImpl {
   int operate_read(const object_t& oid, ::ObjectOperation *o, bufferlist *pbl);
   int aio_operate(const object_t& oid, ::ObjectOperation *o,
 		  AioCompletionImpl *c, const SnapContext& snap_context);
-  int aio_operate_read(const object_t& oid, ::ObjectOperation *o, AioCompletionImpl *c, bufferlist *pbl);
+  int aio_operate_read(const object_t& oid, ::ObjectOperation *o,
+		       AioCompletionImpl *c, int flags, bufferlist *pbl);
 
   struct C_aio_Ack : public Context {
     librados::AioCompletionImpl *c;
diff --git a/src/librados/librados.cc b/src/librados/librados.cc
index 3700a4d1be0e..5e8b38f0b001 100644
--- a/src/librados/librados.cc
+++ b/src/librados/librados.cc
@@ -891,10 +891,28 @@ int librados::IoCtx::aio_operate(const std::string& oid, AioCompletion *c,
 				  snapc);
 }
 
-int librados::IoCtx::aio_operate(const std::string& oid, AioCompletion *c, librados::ObjectReadOperation *o, bufferlist *pbl)
+int librados::IoCtx::aio_operate(const std::string& oid, AioCompletion *c,
+				 librados::ObjectReadOperation *o,
+				 bufferlist *pbl)
+{
+  object_t obj(oid);
+  return io_ctx_impl->aio_operate_read(obj, (::ObjectOperation*)o->impl, c->pc,
+				       0, pbl);
+}
+
+int librados::IoCtx::aio_operate(const std::string& oid, AioCompletion *c,
+				 librados::ObjectReadOperation *o, 
+				 snap_t snapid, int flags, bufferlist *pbl)
 {
   object_t obj(oid);
-  return io_ctx_impl->aio_operate_read(obj, (::ObjectOperation*)o->impl, c->pc, pbl);
+  int op_flags = 0;
+  if (flags & OPERATION_BALANCE_READS)
+    op_flags |= CEPH_OSD_FLAG_BALANCE_READS;
+  if (flags & OPERATION_LOCALIZE_READS)
+    op_flags |= CEPH_OSD_FLAG_LOCALIZE_READS;
+
+  return io_ctx_impl->aio_operate_read(obj, (::ObjectOperation*)o->impl, c->pc,
+				       op_flags, pbl);
 }
 
 void librados::IoCtx::snap_set_read(snap_t seq)