thread waiting at pthread_mutex_lock() does not leave the cpu

Hi all,

I am running a process which creates 12 threads and its function is to pass messages between other processes. Platform is montavista

The problem is :
one of its thread lock a mutex and before it can unlock it another thread try to lock that mutex and gets blocked, but for next 7 seconds no other thread get scheduled.

20 062244:538 Acquiring lock
20 062244:538 Acquired lock
20 062244:538 Message for PEER node
20 062244:676 Acquiring lock
20 062251:131 ############handleMessages: accept returned with fd:


function which was shared is
int handleMessage(void *pkt, int len)
{
int sockfd;
log("Acquiring lock");
pthread_mutex_lock(&data_handler_mutex);
log("Acquired lock");
sMessageHeader *temp = &(((sMessagePacket *)pkt)->msgHdr);
if((len != EXT_MSG_PKT_SIZE) && (len != MSG_PKT_SIZE))
log("\n ~~~~~~~ %s called for invalid length: %d",func, len); ........


please tell me what could be the problem.

Isn't that what's supposed to happen? One thread locks the mutex, all others have to wait for it to unlock it.

Viggy

Thanks for reply,
Other threads except the one which is waiting to get lock do not use that mutex. I guess i found the problem and it is with send() which actually blocks later in that function.