CCS+C6678LE开发记录11:多核协作(IPC)入门

为更好地发挥C6678的多核性能，需要用到多核协作。幸运的是，我们可以使用官方提供的IPC模块。

IPC=Inter-Processor Communication, 核间通信，粗略来说就是多核之间进行信息、数据交换。

作为入门篇，本文不打算深入讨论IPC，仅仅列出自带的两个简单示例：Notify和MessageQ.

“通知”(Notify)模型

“消息队列”(MessageQ)模型

以下介绍Notify示例的创建过程以及测试结果。

首先新建一个项目，取名demo_ipcNotify,项目类型从模板中选择

选择"IPC and I/O Examples"分支下的“C6678 Examples”

然后【Next】，在XDCtools version选择3.23.4.60（不带"core"后缀的那一个）

创建并编译链接无错误之后执行Debug

建议勾选下方的"Create a debug group for selected cores"

如果没有选，可以在稍后执行如下操作

分组的好处是，当有多个核心加载时，不必一一启动，只需要在组别上点击启动（分组下所有核心全部启动）

这样做虽然不是必要的，但建议这样做。

如果勾选了分组，将会是如下这个样子，测试的时候只需在"Group 1"上点击一次【Step On(继续将执行)】

以下是测试示例的输出(中间有部分省略)

[C66xx_6] main: MultiProc id = 6main: MultiProc name = CORE6[C66xx_7] main: MultiProc id = 7main: MultiProc name = CORE7[C66xx_0] main: MultiProc id = 0[C66xx_1] main: MultiProc id = 1[C66xx_2] main: MultiProc id = 2[C66xx_3] main: MultiProc id = 3[C66xx_4] main: MultiProc id = 4[C66xx_5] main: MultiProc id = 5[C66xx_0] main: MultiProc name = CORE0[C66xx_1] main: MultiProc name = CORE1[C66xx_2] main: MultiProc name = CORE2[C66xx_3] main: MultiProc name = CORE3[C66xx_4] main: MultiProc name = CORE4[C66xx_5] main: MultiProc name = CORE5[C66xx_0] tsk1_func: Sent request #0 to CORE1[C66xx_1] tsk1_func: Received request #1 from CORE0tsk1_func: Sent request #1 to CORE2[C66xx_2] tsk1_func: Received request #1 from CORE1tsk1_func: Sent request #1 to CORE3[C66xx_3] tsk1_func: Received request #1 from CORE2tsk1_func: Sent request #1 to CORE4///省略///[C66xx_3] tsk1_func: Received request #10 from CORE2tsk1_func: Sent request #10 to CORE4Test completed[C66xx_4] tsk1_func: Received request #10 from CORE3tsk1_func: Sent request #10 to CORE5Test completed[C66xx_5] tsk1_func: Received request #10 from CORE4tsk1_func: Sent request #10 to CORE6Test completed[C66xx_6] tsk1_func: Received request #10 from CORE5tsk1_func: Sent request #10 to CORE7Test completed[C66xx_7] tsk1_func: Received request #10 from CORE6tsk1_func: Sent request #10 to CORE0Test completed[C66xx_0] tsk1_func: Received request #10 from CORE7Test completed

类似的可以新建一个MessageQ示例项目

后续步骤同上，测试的输出如下(中间有部分省略)

[C66xx_1] Start the main loop[C66xx_5] Start the main loop[C66xx_7] Start the main loop[C66xx_6] Start the main loop[C66xx_0] Start the main loop[C66xx_2] Start the main loop[C66xx_3] Start the main loop[C66xx_4] Start the main loop[C66xx_0] Sending a message #1 to CORE1[C66xx_1] Sending a message #1 to CORE2[C66xx_2] Sending a message #1 to CORE3[C66xx_3] Sending a message #1 to CORE4[C66xx_4] Sending a message #1 to CORE5[C66xx_5] Sending a message #1 to CORE6[C66xx_6] Sending a message #1 to CORE7[C66xx_7] Sending a message #1 to CORE0///省略///[C66xx_5] Sending a message #9 to CORE6[C66xx_6] Sending a message #9 to CORE7[C66xx_7] Sending a message #9 to CORE0[C66xx_0] Sending a message #10 to CORE1[C66xx_1] Sending a message #10 to CORE2The test is complete[C66xx_2] Sending a message #10 to CORE3The test is complete[C66xx_3] Sending a message #10 to CORE4The test is complete[C66xx_4] Sending a message #10 to CORE5The test is complete[C66xx_5] Sending a message #10 to CORE6The test is complete[C66xx_6] Sending a message #10 to CORE7The test is complete[C66xx_7] Sending a message #10 to CORE0The test is complete[C66xx_0] The test is complete

最后附上示例代码(模板生成的，仅删除部分注释，其他未做改动)

示例Notify的主要代码

#include <xdc/std.h>/*  XDC.RUNTIME module Headers    */#include <xdc/runtime/System.h>/*  IPC module Headers           */#include <ti/ipc/MultiProc.h>#include <ti/ipc/Notify.h>#include <ti/ipc/Ipc.h>/*  BIOS6 module Headers         */#include <ti/sysbios/knl/Semaphore.h>#include <ti/sysbios/knl/Task.h>#include <ti/sysbios/BIOS.h>/*  To get globals from .cfg Header */#include <xdc/cfg/global.h>#define INTERRUPT_LINE  0/* Notify event number that the app uses */#define EVENTID         10/* Number of times to run the loop */#define NUMLOOPS        10 UInt32 seq = 0;UInt16 recvProcId;UInt16 srcProc, dstProc;/* *  ======== cbFxn ======== *  This function was registered with Notify. It is called when any event is *  sent to this processor. */Void cbFxn(UInt16 procId, UInt16 lineId, UInt32 eventId, UArg arg,UInt32 payload){/* The payload is a sequence number. */recvProcId = procId;seq = payload;Semaphore_post(semHandle);}/* *  ======== tsk0_func ======== *  Sends an event to the next processor then pends on a semaphore. *  The semaphore is posted by the callback function. */Void tsk0_func(UArg arg0, UArg arg1){Int i = 1;Int status;if (MultiProc_self() == 0){while (i <= NUMLOOPS){/* Send an event to the next processor */status = Notify_sendEvent(dstProc, INTERRUPT_LINE, EVENTID, i,TRUE);/* Continue until remote side is up */if (status < 0){continue;}System_printf("tsk1_func: Sent request #%d to %s\n", seq,MultiProc_getName(dstProc));/* Wait to be released by the cbFxn posting the semaphore */Semaphore_pend(semHandle, BIOS_WAIT_FOREVER);System_printf("tsk1_func: Received request #%d from %s\n", seq,MultiProc_getName(recvProcId));/* increment for next iteration */i++;}}else{while (seq < NUMLOOPS){/* wait forever on a semaphore, semaphore is posted in callback */Semaphore_pend(semHandle, BIOS_WAIT_FOREVER);System_printf("tsk1_func: Received request #%d from %s\n", seq,MultiProc_getName(recvProcId));/* Send an event to the next processor */status = Notify_sendEvent(dstProc, INTERRUPT_LINE, EVENTID, seq,TRUE);if (status < 0){System_abort("sendEvent failed\n");}System_printf("tsk1_func: Sent request #%d to %s\n", seq,MultiProc_getName(dstProc));}}System_printf("Test completed\n");BIOS_exit(0);}/* *  ======== main ======== *  Synchronizes all processors (in Ipc_start), calls BIOS_start, and registers  *  for an incoming event */Int main(Int argc, Char* argv[]){Int status;UInt numProcs = MultiProc_getNumProcessors();/* *  Determine which processors Notify will communicate with based on the *  local MultiProc id.  Also, create a processor-specific Task. */srcProc = ((MultiProc_self() - 1 + numProcs) % numProcs);dstProc = ((MultiProc_self() + 1) % numProcs);System_printf("main: MultiProc id = %d\n", MultiProc_self());System_printf("main: MultiProc name = %s\n",MultiProc_getName(MultiProc_self()));/* *  Ipc_start() calls Ipc_attach() to synchronize all remote processors *  because 'Ipc.procSync' is set to 'Ipc.ProcSync_ALL' in *.cfg */status = Ipc_start();if (status < 0){System_abort("Ipc_start failed\n");}/* *  Register call back with Notify. It will be called when the processor *  with id = srcProc sends event number EVENTID to this processor. */status = Notify_registerEvent(srcProc, INTERRUPT_LINE, EVENTID,(Notify_FnNotifyCbck) cbFxn, NULL);if (status < 0){System_abort("Notify_registerEvent failed\n");}BIOS_start();return (0);}

示例MessageQ的主要代码

#include <xdc/std.h>#include <string.h>/*  XDC.RUNTIME module Headers    */#include <xdc/runtime/System.h>#include <xdc/runtime/IHeap.h>/*  IPC module Headers           */#include <ti/ipc/Ipc.h>#include <ti/ipc/MessageQ.h>#include <ti/ipc/HeapBufMP.h>#include <ti/ipc/MultiProc.h>/*  BIOS6 module Headers         */#include <ti/sysbios/BIOS.h>#include <ti/sysbios/knl/Task.h>/*  To get globals from .cfg Header */#include <xdc/cfg/global.h>#define HEAP_NAME   "myHeapBuf"#define HEAPID      0#define NUMLOOPS    10Char localQueueName[10];Char nextQueueName[10];UInt16 nextProcId;/* *  ======== tsk0_func ======== *  Allocates a message and ping-pongs the message around the processors. *  A local message queue is created and a remote message queue is opened. *  Messages are sent to the remote message queue and retrieved from the *  local MessageQ. */Void tsk0_func(UArg arg0, UArg arg1){MessageQ_Msg msg;MessageQ_Handle messageQ;MessageQ_QueueId remoteQueueId;Int status;UInt16 msgId = 0;HeapBufMP_Handle heapHandle;HeapBufMP_Params heapBufParams;if (MultiProc_self() == 0){/* *  Create the heap that will be used to allocate messages. */HeapBufMP_Params_init(&heapBufParams);heapBufParams.regionId = 0;heapBufParams.name = HEAP_NAME;heapBufParams.numBlocks = 1;heapBufParams.blockSize = sizeof(MessageQ_MsgHeader);heapHandle = HeapBufMP_create(&heapBufParams);if (heapHandle == NULL){System_abort("HeapBufMP_create failed\n");}}else{/* Open the heap created by the other processor. Loop until opened. */do{status = HeapBufMP_open(HEAP_NAME, &heapHandle);/* *  Sleep for 1 clock tick to avoid inundating remote processor *  with interrupts if open failed */if (status < 0){Task_sleep(1);}} while (status < 0);}/* Register this heap with MessageQ */MessageQ_registerHeap((IHeap_Handle) heapHandle, HEAPID);/* Create the local message queue */messageQ = MessageQ_create(localQueueName, NULL);if (messageQ == NULL){System_abort("MessageQ_create failed\n");}/* Open the remote message queue. Spin until it is ready. */do{status = MessageQ_open(nextQueueName, &remoteQueueId);/* *  Sleep for 1 clock tick to avoid inundating remote processor *  with interrupts if open failed */if (status < 0){Task_sleep(1);}} while (status < 0);if (MultiProc_self() == 0){/* Allocate a message to be ping-ponged around the processors */msg = MessageQ_alloc(HEAPID, sizeof(MessageQ_MsgHeader));if (msg == NULL){System_abort("MessageQ_alloc failed\n");}/* *  Send the message to the next processor and wait for a message *  from the previous processor. */System_printf("Start the main loop\n");while (msgId < NUMLOOPS){/* Increment...the remote side will check this */msgId++;MessageQ_setMsgId(msg, msgId);System_printf("Sending a message #%d to %s\n", msgId,nextQueueName);/* send the message to the remote processor */status = MessageQ_put(remoteQueueId, msg);if (status < 0){System_abort("MessageQ_put had a failure/error\n");}/* Get a message */status = MessageQ_get(messageQ, &msg, MessageQ_FOREVER);if (status < 0){System_abort("This should not happen since timeout is forever\n");}}}else{/* *  Wait for a message from the previous processor and *  send it to the next processor */System_printf("Start the main loop\n");while (TRUE){/* Get a message */status = MessageQ_get(messageQ, &msg, MessageQ_FOREVER);if (status < 0){System_abort("This should not happen since timeout is forever\n");}System_printf("Sending a message #%d to %s\n",MessageQ_getMsgId(msg),     nextQueueName);/* Get the message id */msgId = MessageQ_getMsgId(msg);/* send the message to the remote processor */status = MessageQ_put(remoteQueueId, msg);if (status < 0){System_abort("MessageQ_put had a failure/error\n");}/* test done */if (msgId >= NUMLOOPS){break;}}}System_printf("The test is complete\n");BIOS_exit(0);}/* *  ======== main ======== *  Synchronizes all processors (in Ipc_start) and calls BIOS_start */Int main(Int argc, Char* argv[]){Int status;nextProcId = (MultiProc_self() + 1) % MultiProc_getNumProcessors();/* Generate queue names based on own proc ID and total number of procs */System_sprintf(localQueueName, "%s", MultiProc_getName(MultiProc_self()));System_sprintf(nextQueueName, "%s", MultiProc_getName(nextProcId));/* *  Ipc_start() calls Ipc_attach() to synchronize all remote processors *  because 'Ipc.procSync' is set to 'Ipc.ProcSync_ALL' in *.cfg */status = Ipc_start();if (status < 0){System_abort("Ipc_start failed\n");}BIOS_start();return (0);}

本文原创，博文地址
http://blog.csdn.net/fengyhack/article/details/44034941