Implement master client for reading training tasks

CMakeLists.txt

@@ -126,6 +126,7 @@ endif(WITH_GPU)
 
 add_subdirectory(proto)
 add_subdirectory(paddle)
+add_subdirectory(go/master/c)
 add_subdirectory(python)
 add_subdirectory(go/pserver/cclient)
 

go/cmake/golang.cmake

@@ -26,27 +26,23 @@ function(GO_LIBRARY NAME BUILD_TYPE)
 
   # automatically get all dependencies specified in the source code
   # for given target.
-  add_custom_target(goGet env GOPATH=${GOPATH} ${CMAKE_Go_COMPILER} get -d ${rel}/...)
+  add_custom_target(${NAME}_goGet env GOPATH=${GOPATH} ${CMAKE_Go_COMPILER} get -d ${rel}/...)
 
   # make a symlink that references Paddle inside $GOPATH, so go get
   # will use the local changes in Paddle rather than checkout Paddle
   # in github.
-  add_custom_target(copyPaddle
+  add_custom_target(${NAME}_copyPaddle
     COMMAND rm -rf ${PADDLE_IN_GOPATH}/Paddle
     COMMAND ln -sf ${PADDLE_DIR} ${PADDLE_IN_GOPATH}/Paddle)
-  add_dependencies(goGet copyPaddle)
+  add_dependencies(${NAME}_goGet ${NAME}_copyPaddle)
 
   add_custom_command(OUTPUT ${OUTPUT_DIR}/.timestamp
     COMMAND env GOPATH=${GOPATH} ${CMAKE_Go_COMPILER} build ${BUILD_MODE}
-     -gcflags=-shared -asmflags=-shared -installsuffix=_shared -a
      -o "${CMAKE_CURRENT_BINARY_DIR}/${LIB_NAME}"
     ${CMAKE_GO_FLAGS} ${GO_SOURCE}
     WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR})
 
   add_custom_target(${NAME} ALL DEPENDS ${OUTPUT_DIR}/.timestamp ${ARGN})
-  add_dependencies(${NAME} goGet)
+  add_dependencies(${NAME} ${NAME}_goGet)
 
-  if(NOT BUILD_TYPE STREQUAL "STATIC")
-    install(PROGRAMS ${CMAKE_CURRENT_BINARY_DIR}/${LIB_NAME} DESTINATION bin)
-  endif()
 endfunction(GO_LIBRARY)

go/connection/conn.go

@@ -2,9 +2,10 @@ package connection
 
 import (
 	"errors"
-	"log"
 	"net/rpc"
 	"sync"
+
+	log "github.com/sirupsen/logrus"
 )
 
 // TODO(helin): add TCP re-connect logic
@@ -65,7 +66,7 @@ func (c *Conn) Connect(addr string) error {
 	} else {
 		err := client.Close()
 		if err != nil {
-			log.Println(err)
+			log.Errorln(err)
 		}
 
 		return errors.New("client already set from a concurrent goroutine")

go/master/c/CMakeLists.txt

@@ -0,0 +1,21 @@
+cmake_minimum_required(VERSION 3.0)
+
+get_filename_component(PARENT_DIR ${CMAKE_CURRENT_SOURCE_DIR} DIRECTORY)
+get_filename_component(PARENT_DIR ${PARENT_DIR} DIRECTORY)
+set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${PARENT_DIR}/cmake")
+
+project(cxx_go C Go)
+
+include(golang)
+include(flags)
+
+set(MASTER_LIB_NAME "paddle_master")
+go_library(${MASTER_LIB_NAME} SHARED)
+
+if(PROJ_ROOT)
+  add_custom_command(OUTPUT ${PROJ_ROOT}/python/paddle/v2/master/lib${MASTER_LIB_NAME}.so
+    COMMAND rm ${CMAKE_CURRENT_BINARY_DIR}/lib${MASTER_LIB_NAME}.h
+    COMMAND cp ${CMAKE_CURRENT_BINARY_DIR}/lib${MASTER_LIB_NAME}.so ${PROJ_ROOT}/python/paddle/v2/master/
+    DEPENDS ${MASTER_LIB_NAME})
+  add_custom_target(paddle_master_shared ALL DEPENDS ${PROJ_ROOT}/python/paddle/v2/master/lib${MASTER_LIB_NAME}.so)
+endif(PROJ_ROOT)

go/master/c/client.go

@@ -0,0 +1,110 @@
+package main
+
+/*
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+#define PADDLE_MASTER_OK    0
+#define PADDLE_MASTER_ERROR -1
+
+typedef int paddle_master_client;
+*/
+import "C"
+
+import (
+	"sync"
+	"unsafe"
+
+	"github.com/PaddlePaddle/Paddle/go/master"
+	log "github.com/sirupsen/logrus"
+)
+
+var nullPtr = unsafe.Pointer(uintptr(0))
+var mu sync.Mutex
+var handleMap = make(map[C.paddle_master_client]*master.Client)
+var curHandle C.paddle_master_client
+
+func add(c *master.Client) C.paddle_master_client {
+	mu.Lock()
+	defer mu.Unlock()
+	client := curHandle
+	curHandle++
+	handleMap[client] = c
+	return client
+}
+
+func get(client C.paddle_master_client) *master.Client {
+	mu.Lock()
+	defer mu.Unlock()
+	return handleMap[client]
+}
+
+func remove(client C.paddle_master_client) *master.Client {
+	mu.Lock()
+	defer mu.Unlock()
+	h := handleMap[client]
+	delete(handleMap, client)
+	return h
+}
+
+type addresser string
+
+func (a addresser) Address() string {
+	return string(a)
+}
+
+//export paddle_new_master_client
+func paddle_new_master_client(addr *C.char, bufSize int) C.paddle_master_client {
+	a := C.GoString(addr)
+	c := master.NewClient(addresser(a), bufSize)
+	return add(c)
+}
+
+//export paddle_release_master_client
+func paddle_release_master_client(client C.paddle_master_client) {
+	remove(client)
+}
+
+//export paddle_set_dataset
+func paddle_set_dataset(client C.paddle_master_client, path **C.char, size C.int) C.int {
+	c := get(client)
+	var paths []string
+	for i := 0; i < int(size); i++ {
+		ptr := (**C.char)(unsafe.Pointer(uintptr(unsafe.Pointer(path)) + uintptr(i)*unsafe.Sizeof(*path)))
+		str := C.GoString(*ptr)
+		paths = append(paths, str)
+	}
+	err := c.SetDataset(paths)
+	if err != nil {
+		log.Errorln(err)
+		return C.PADDLE_MASTER_ERROR
+	}
+
+	return C.PADDLE_MASTER_OK
+}
+
+//export paddle_next_record
+func paddle_next_record(client C.paddle_master_client, record **C.uchar) C.int {
+	c := get(client)
+	r := c.NextRecord()
+	if len(r) == 0 {
+		*record = (*C.uchar)(nullPtr)
+		return 0
+	}
+
+	size := C.size_t(len(r))
+	*record = (*C.uchar)(C.malloc(size))
+	C.memcpy(unsafe.Pointer(*record), unsafe.Pointer(&r[0]), size)
+	return C.int(size)
+}
+
+//export mem_free
+func mem_free(p unsafe.Pointer) {
+	// "free" may be a better name for this function, but doing so
+	// will cause calling any function of this library from Python
+	// ctypes hanging.
+	C.free(p)
+}
+
+func main() {}

go/master/client.go

@@ -1,10 +1,12 @@
 package master
 
 import (
-	"log"
+	"os"
 	"time"
 
 	"github.com/PaddlePaddle/Paddle/go/connection"
+	"github.com/PaddlePaddle/recordio"
+	log "github.com/sirupsen/logrus"
 )
 
 // Addresser provide the address of the master server.
@@ -15,16 +17,61 @@ type Addresser interface {
 // Client is the client of the master server.
 type Client struct {
 	conn *connection.Conn
+	ch   chan []byte
 }
 
 // NewClient creates a new Client.
-func NewClient(addr Addresser) *Client {
+//
+// bufSize is the record buffer size. NextRecord will read from this
+// buffer.
+func NewClient(addr Addresser, bufSize int) *Client {
 	c := &Client{}
 	c.conn = connection.New()
+	c.ch = make(chan []byte, bufSize)
 	go c.monitorMaster(addr)
+	go c.getRecords()
 	return c
 }
 
+func (c *Client) getRecords() {
+	for {
+		t, err := c.getTask()
+		if err != nil {
+			// TODO(helin): wait before move on with next
+			// getTask call.
+			log.Errorln(err)
+			continue
+		}
+
+		for _, chunk := range t.Chunks {
+			f, err := os.Open(chunk.Path)
+			if err != nil {
+				log.Errorln(err)
+				continue
+			}
+
+			s := recordio.NewRangeScanner(f, &chunk.Index, -1, -1)
+			for s.Scan() {
+				c.ch <- s.Record()
+			}
+
+			if s.Err() != nil {
+				log.Errorln(err, chunk.Path)
+			}
+
+			err = f.Close()
+			if err != nil {
+				log.Errorln(err)
+			}
+		}
+
+		// We treat a task as finished whenever the last data
+		// instance of the task is read. This is not exactly
+		// correct, but a reasonable approximation.
+		c.taskFinished(t.ID)
+	}
+}
+
 func (c *Client) monitorMaster(addr Addresser) {
 	lastMaster := ""
 	monitor := func() {
@@ -35,12 +82,12 @@ func (c *Client) monitorMaster(addr Addresser) {
 			if curMaster == "" {
 				err := c.conn.Close()
 				if err != nil {
-					log.Println(err)
+					log.Errorln(err)
 				}
 			} else {
 				err := c.conn.Connect(curMaster)
 				if err != nil {
-					log.Println(err)
+					log.Errorln(err)
 
 					// connect to addr failed, set
 					// to last known addr in order
@@ -69,14 +116,22 @@ func (c *Client) SetDataset(globPaths []string) error {
 	return c.conn.Call("Service.SetDataset", globPaths, nil)
 }
 
-// GetTask gets a new task from the master server.
-func (c *Client) GetTask() (Task, error) {
+// getTask gets a new task from the master server.
+func (c *Client) getTask() (Task, error) {
 	var t Task
 	err := c.conn.Call("Service.GetTask", 0, &t)
 	return t, err
 }
 
 // TaskFinished tells the master server a task is finished.
-func (c *Client) TaskFinished(taskID int) error {
+func (c *Client) taskFinished(taskID int) error {
 	return c.conn.Call("Service.TaskFinished", taskID, nil)
 }
+
+// NextRecord returns next record in the dataset.
+//
+// NextRecord will block until the next record is available. It is
+// thread-safe.
+func (c *Client) NextRecord() []byte {
+	return <-c.ch
+}