i write readers and writers where the kernel have to syncronize between them and block writer who already read a massage
when i am in the queue waiting I get signal so I do the fallowing
while (i_Allready_Read(myf) == ALLREADY_READ || isExistWriter == false )
//while (!(i_Allready_Read(aliveProc,current->pid)))
{
int i, is_sig = 0;
printk(KERN_INFO "\n\n*****entered set in read ******\n\n" );
if (i_Allready_Read(myf) == ALLREADY_READ )
wait_event_interruptible (readWaitQ1, !i_Allready_Re开发者_JAVA技巧ad(myf));
else
wait_event_interruptible (readWaitQ1, isExistWriter);
//printk(KERN_INFO "Read Wakeup %d\n",current->pid);
for (i = 0; i < _NSIG_WORDS && !is_sig; i++)
{
is_sig = current->pending.signal.sig[i] & ~current->blocked.sig[i];
}
if (is_sig)
{
handledClose(myf);
module_put (THIS_MODULE);
return -EINTR;
}
}
return 0;//success
}
inline void handledClose(struct file *myf)//v
{ /* *if we close the writer other writer *would be able to enter to permissiones */
if (myf == writerpid )
{
isExistWriter = DOESNT_EXIST;
//printk(KERN_INFO "procfs_close : this is pid that just closed %d \n", writerpid);
}
/*
*else its a reader so our numofreaders
*need to decremented
*/
else
{
removeFromArr(myf);
numOfReaders--;
}
}
and my close does nothing ...
what did i do wrong?
Where are you waking up the wait queue?
You should be calling wake_up(readWaitQ1);
somewhere. Possible after you set isExistWriter
to true.
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