epics/pcas
0
0
Fork 0
Code Issues Pull Requests Projects Wiki Activity

rearranged the rxTask to remove possible race condition

Browse Source
This commit is contained in:
John Winans
1992-05-20 10:18:18 +00:00
parent aa54b9c151
commit 88faf64382
1 changed files with 21 additions and 18 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/drv/drvBitBus.c
+21 -18
View File
@@ -473,7 +473,7 @@ static int
xvmeRxTask(link)
int link;
{
int rxStatus; /* current state of the receiver */
int rxState; /* current state of the receiver */
#define BBRX_HEAD 1
#define BBRX_DATA 2
#define BBRX_RCMD 3
@@ -487,7 +487,7 @@ int link;
int lockKey; /* used for intLock calls */
rxMsg = (unsigned char *) NULL;
rxStatus = BBRX_HEAD;
rxState = BBRX_HEAD;
rxTCount = 0;
rxDpvtHead = (struct dpvtBitBusHead *) NULL;
@@ -519,9 +519,9 @@ int link;
{
/* check to see if we got a data byte or a command byte */
if ((pXvmeLink[link]->bbRegs->fifo_stat & XVME_RCMD) == XVME_RCMD)
rxStatus = BBRX_RCMD;
rxState = BBRX_RCMD;
switch (rxStatus) {
switch (rxState) {
case BBRX_HEAD: /* getting the head of a new message */
rxHead[rxTCount] = pXvmeLink[link]->bbRegs->data;
if (bbDebug>21)
@@ -551,6 +551,15 @@ int link;
/* Delete the node from the list */
listDel(&(pXvmeLink[link]->pbbLink->busyList), rxDpvtHead);
/* If busy list is empty, stop the dog */
if (pXvmeLink[link]->pbbLink->busyList.head == NULL)
wdCancel(pXvmeLink[link]->watchDogId);
/* Wake up Link Task in case was waiting on "this" node */
semGive(pXvmeLink[link]->pbbLink->linkEventSem);
FASTUNLOCK(&(pXvmeLink[link]->pbbLink->busyList.sem));
/* decrement the number of outstanding messages to the node */
(pXvmeLink[link]->pbbLink->deviceStatus[rxDpvtHead->txMsg.node])--;
@@ -560,21 +569,21 @@ int link;
rxDpvtHead->rxMsg.tasks = rxHead[3];
rxDpvtHead->rxMsg.cmd = rxHead[4];
rxMsg = rxDpvtHead->rxMsg.data;
rxDpvtHead->status = BB_OK; /* OK, unless BB_LENGTH */
rxStatus = BBRX_DATA; /* finish reading till RCMD */
rxState = BBRX_DATA; /* finish reading till RCMD */
break; /* get out of the while() */
}
}
rxDpvtHead = rxDpvtHead->next; /* Keep looking */
}
FASTUNLOCK(&(pXvmeLink[link]->pbbLink->busyList.sem));
if (rxDpvtHead == NULL)
{
if (bbDebug)
printf("xvmeRxTask(%d): msg from node %d unsolicited!\n", link, rxHead[2]);
rxStatus = BBRX_IGN; /* nothing waiting... toss it */
FASTUNLOCK(&(pXvmeLink[link]->pbbLink->busyList.sem));
rxState = BBRX_IGN; /* nothing waiting... toss it */
}
}
break;
@@ -583,7 +592,7 @@ int link;
ch = pXvmeLink[link]->bbRegs->data;
if (rxTCount >= rxDpvtHead->rxMaxLen)
{
rxStatus = BBRX_IGN; /* toss the rest of the data */
rxState = BBRX_IGN; /* toss the rest of the data */
rxDpvtHead->status = BB_LENGTH; /* set driver status */
if (bbDebug>22)
printf("xvmeRxTask(%d): %02.2X (Ignored)\n", link, ch);
@@ -624,20 +633,14 @@ int link;
printf("xvmeRxTask(%d): invoking the callbackRequest\n", link);
callbackRequest(rxDpvtHead); /* schedule completion processing */
}
/* If there is a semaphore for synchronous I/O, unlock it */
if (rxDpvtHead->psyncSem != NULL)
semGive(*(rxDpvtHead->psyncSem));
/* If busy list is empty, stop the dog */
if (pXvmeLink[link]->pbbLink->busyList.head == NULL)
wdCancel(pXvmeLink[link]->watchDogId);
/* Wake up Link Task in case the req queue was waiting on "this" node */
semGive(pXvmeLink[link]->pbbLink->linkEventSem);
}
/* Reset the state of the RxTask to expect a new message */
rxMsg = (unsigned char *) NULL;
rxStatus = BBRX_HEAD;
rxState = BBRX_HEAD;
rxTCount = 0;
rxDpvtHead = (struct dpvtBitBusHead *) NULL;
@@ -655,7 +658,7 @@ int link;
}
rxMsg = (unsigned char *) NULL;
rxStatus = BBRX_HEAD;
rxState = BBRX_HEAD;
rxTCount = 0;
rxDpvtHead = (struct dpvtBitBusHead *) NULL;