static
void readerthread(void *junk, unsigned long num) {
(void)junk;
if(num < 80) {
//kprintf_n("Thread %lu trying to acquire read lock\n", num);
random_yielder(4);
rwlock_acquire_read(testrwlock);
random_yielder(4);
kprintf_n("Thread %lu: Reader val:%lu\n", num, testval1);
for(int i=0; i<40000; i++);
random_yielder(4);
rwlock_release_read(testrwlock);
random_yielder(4);
//kprintf_n("Thread %lu released read lock\n", num);
V(donesem);
}
else {
//kprintf_n("Thread %lu trying to acquire write lock\n", num);
random_yielder(4);
rwlock_acquire_write(testrwlock);
random_yielder(4);
testval1++;
kprintf_n("Thread %lu: Writer val:%lu\n", num, testval1);
for(int i=0; i<40000; i++);
random_yielder(4);
rwlock_release_write(testrwlock);
random_yielder(4);
//kprintf_n("Thread %lu released write lock\n", num);
V(donesem);
}
return;
}
static
void
rwlocktestthread_reader(void *junk, unsigned long num)
{
int i;
(void)junk;
unsigned long tv_1;
unsigned long tv_2;
unsigned long tv_3;
for (i=0; i<NLOCKLOOPS; i++) {
rwlock_acquire_read(testrwlock);
tv_1 = testval1;
tv_2 = testval2;
tv_3 = testval3;
if(tv_1 != testval1){
fail_reader(num, "testval1 changed");
}
if(tv_2 != testval2){
fail_reader(num, "testval2 changed");
}
if(tv_3 != testval3){
fail_reader(num, "testval3 changed");
}
// if (testval2 != testval1*testval1) {
// fail_reader(num, "testval2/testval1");
// }
//
// if (testval2%3 != (testval3*testval3)%3) {
// fail_reader(num, "testval2/testval3");
// }
//
// if (testval3 != testval1%3) {
// fail_reader(num, "testval3/testval1");
// }
//
// if (testval1 != num) {
// fail_reader(num, "testval1/num");
// }
//
// if (testval2 != num*num) {
// fail_reader(num, "testval2/num");
// }
//
// if (testval3 != num%3) {
// fail_reader(num, "testval3/num");
// }
rwlock_release_read(testrwlock);
}
V(donesem);
}
static
void
fail_reader(unsigned long num, const char *msg)
{
kprintf("Reader thread %lu: Mismatch on %s\n", num, msg);
kprintf("Test failed\n");
rwlock_release_read(testrwlock);
V(donesem);
thread_exit();
}
static
void
readtestthread(void *junk, unsigned long num)
{
int i;
(void)junk;
unsigned long localtestval ;
int j ;
for (i=0; i<NRWLOOPS; i++) {
rwlock_acquire_read(testrwlock);
kprintf("Lock Acquired for Read Thread %lu \n", num);
localtestval = testval4 ;
//Empty loop to pass time. No other thread should modify the value in this time.
for(j=0 ; j<3000 ;j++) ;
//assert operation to verify whether the value has been changed after the lock is acquired.
KASSERT(localtestval == testval4);
kprintf("Read Thread %lu : Read Value %lu \n", num, testval4);
kprintf("Lock Released for Read Thread %lu \n", num);
rwlock_release_read(testrwlock);
}
V(donesem);
}