vxworks信号量之疑
今天在运行一个信号量的程序时，感觉结果挺奇怪的，程序如下：
这个问题暂时放在这，以后慢慢研究，如果哪位高手能指点指点的话，不甚感激。
/* include files */
#include "vxWorks.h"
#include "wdLib.h"
#include "stdio.h"
#include "semLib.h"
#include "taskLib.h"
#include "usrLib.h"
#include "sysLib.h"
/* defines */
#define TASK_PRIORITY 101
#define TASK_STACK_SIZE 5000
#define TIME_BETWEEN_INTERRUPTS 1 /* 1 tick */
#define TASK_WORK_TIME 2 /* 2 ticks */
#define NUM_OF_GIVES 30
/* globals */
/* counting or binary semaphore ID */
LOCAL SEM_ID semId = NULL;
/* watchdog ID */
LOCAL WDOG_ID wdId = NULL;
/* tid of syncTask */
LOCAL int syncTaskTid = 0;
/* Number of times semGive is called */
LOCAL int numToGive = NUM_OF_GIVES;
/* forward declaratiuon */
void syncISR(int);/* ISR to unblock syncTask */
void cleanUp (); /* cleanup routine */
void syncTask (); /* task that needs to be synchronized
* with external events */
/******************************************
* countingSemDemo - demonstrates
task synchronization using counting
* semaphores. User can also select to
use binary semaphore instead of
* counting semaphore in this demonstration,
for comparision between the two
* semaphores.
*
* RETURNS: OK or ERROR
*
*/
STATUS countingSemDemo (
char semType /* counting semaphore type
'c' or binary semaphore
* type 'b'
*/)
{
switch (semType)
{
case 'c':
case 'C':
if ((semId = semCCreate(SEM_Q_PRIORITY,0)) == NULL)
{
perror ("semCCreate");
return (ERROR);
}
break;
case 'b':
case 'B':
if ((semId = semBCreate(SEM_Q_PRIORITY,SEM_EMPTY)) == NULL)
{
perror ("semBCreate");
return (ERROR);
}
break;
default:
printf ("Unknown semType-- must be 'c' or 'b'\n");
return (ERROR);
}
if ((wdId = wdCreate()) == NULL)
{
perror ("wdCreate");
cleanUp ();
return (ERROR);
}
if ((syncTaskTid = taskSpawn ("tsyncTask", TASK_PRIORITY,0,TASK_STACK_SIZE,(FUNCPTR) syncTask,0,0,0,0,0,0,0,0,0,0)) == ERROR)
{
perror ("taskSpawn");
cleanUp();
return (ERROR);
}
/* watchdog simulates hardware interrupts */
if (wdStart (wdId, TIME_BETWEEN_INTERRUPTS,(FUNCPTR) syncISR, numToGive)== ERROR)
{
perror ("wdStart");
cleanUp ();
return (ERROR);
}
/* arbitrary delay to allow
program to complete before clean up */
taskDelay (sysClkRateGet() +((TASK_WORK_TIME + 2) * numToGive));
cleanUp();
return (OK);
}
/*************************************************
* syncTask - synchronizes with interrupts using
* counting or binarysemaphores.
*/
void syncTask (void)
{
int eventCount = 0;
FOREVER
{
if (semTake (semId, WAIT_FOREVER) == ERROR)
{
perror ("syncTask semTake");
return;
}
/* Do "work" */
taskDelay (TASK_WORK_TIME);
semShow (semId,1);
eventCount++;
printf ("semaphore taken %d times\n", eventCount);
}
}
/************************************************
* syncISR - simulates a hardware device
which generates interrupts very
* quickly and synchronizes with
syncTask using semaphores.
*/
void syncISR(int times)
{
semGive (semId);
times--;
if (times > 0)
wdStart (wdId, TIME_BETWEEN_INTERRUPTS,(FUNCPTR) syncISR, times);
}
/********************************************
* cleanUP - deletes the syncTask, deletes the
* semaphore and the watchdog timer previously created
* by countingSemDemo.*/
void cleanUp ()
{
if (syncTaskTid)
taskDelete (syncTaskTid);
if (semId)
semDelete (semId);
if (wdId)
wdDelete (wdId);
}
运行结果：
->sp countingSemDemo,'c'
Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 2 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 1 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 3 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 2 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 4 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 3 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 5 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 4 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 6 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 5 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 7 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 6 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 8 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 7 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 9 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 8 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 10 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 9 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 11 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 10 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 12 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 11 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 13 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 12 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 14 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 13 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 15 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 14 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 15 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 15 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 14 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 16 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 13 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 17 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 12 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 18 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 11 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 19 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 10 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 20 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 9 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 21 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 8 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 22 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 7 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 23 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 6 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 24 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 5 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 25 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 4 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 26 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 3 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 27 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 2 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 28 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 1 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 29 times Semaphore Id : 0x23ce9d0 Semaphore Type : COUNTING Task Queuing : PRIORITY Pended Tasks : 0 Count : 0 Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 30 times->sp countingCountDemo ‘b’
Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 1 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 2 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 3 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 4 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 5 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 6 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 7 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 8 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 9 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 10 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 11 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 12 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 13 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 14 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : FULL Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 15 times Semaphore Id : 0x23ce9d0 Semaphore Type : BINARY Task Queuing : PRIORITY Pended Tasks : 0 State : EMPTY Options : 0x1 SEM_Q_PRIORITY VxWorks Events -------------- Registered Task : NONE Event(s) to Send : N/A Options : N/A semaphore taken 16 times
这个问题暂时放在这，以后慢慢研究，如果哪位高手能指点指点的话，不甚感激。