/*
* Allocate all of memory one page at a time. The same restrictions
* and considerations apply as above.
*/
static
void
test10(void)
{
void *p, *op;
unsigned i, n;
bool bad;
tprintf("Allocating all of memory one page at a time:\n");
op = dosbrk(0);
n = 0;
while ((p = sbrk(PAGE_SIZE)) != (void *)-1) {
markpagelight(op, n);
n++;
}
tprintf("Got %u pages (%zu bytes).\n", n, (size_t)PAGE_SIZE * n);
tprintf("Now freeing them.\n");
bad = false;
for (i=0; i<n; i++) {
if (checkpagelight(op, n - i - 1, false)) {
warnx("FAILED: data corrupt on page %u", i);
bad = true;
}
(void)dosbrk(-PAGE_SIZE);
}
if (bad) {
exit(1);
}
tprintf("Freed %u pages.\n", n);
p = dosbrk(0);
if (p != op) {
errx(1, "FAILURE: break did not return to original value");
}
tprintf("Now let's see if I can allocate another page.\n");
p = dosbrk(PAGE_SIZE);
markpage(p, 0);
if (checkpage(p, 0, false)) {
errx(1, "FAILED: data corrupt");
}
(void)dosbrk(-PAGE_SIZE);
tprintf("Passed sbrk test 10.\n");
success(TEST161_SUCCESS, SECRET, "/testbin/sbrktest");
}
static
void
test11(void)
{
const unsigned num = 256;
void *p;
unsigned i;
bool bad;
printf("Allocating %u pages (%zu bytes).\n", num,
(size_t)PAGE_SIZE * num);
p = dosbrk(num * PAGE_SIZE);
printf("Touching the pages.\n");
for (i=0; i<num; i++) {
markpagelight(p, i);
if (i % 4 == 0) {
printf(".");
}
}
printf("\n");
printf("Checking the pages.\n");
bad = false;
for (i=0; i<num; i++) {
if (checkpagelight(p, i, true)) {
warnx("FAILED: data corrupt");
bad = true;
}
if (i % 4 == 0) {
printf(".");
}
}
printf("\n");
if (bad) {
exit(1);
}
printf("Now NOT freeing the pages. They should get freed on exit.\n");
printf("If not, you'll notice pretty quickly.\n");
}
static
void
test11(void)
{
const unsigned num = 256;
void *p;
unsigned i;
bool bad;
tprintf("Allocating %u pages (%zu bytes).\n", num,
(size_t)PAGE_SIZE * num);
p = dosbrk(num * PAGE_SIZE);
tprintf("Touching the pages.\n");
for (i=0; i<num; i++) {
markpagelight(p, i);
TEST161_LPROGRESS_N(i, 4);
}
tprintf("\n");
tprintf("Checking the pages.\n");
bad = false;
for (i=0; i<num; i++) {
if (checkpagelight(p, i, true)) {
warnx("FAILED: data corrupt");
bad = true;
}
TEST161_LPROGRESS_N(i, 4);
}
printf("\n");
if (bad) {
exit(1);
}
tprintf("Now NOT freeing the pages. They should get freed on exit.\n");
tprintf("If not, you'll notice pretty quickly.\n");
success(TEST161_SUCCESS, SECRET, "/testbin/sbrktest");
}
static
void
test23(void)
{
// Make sure sbrk is freeing memory. This allocates, in total, just over 4M
// of memory, but moves the heap breakpoint in such a way that only one page
// should ever be required. This test doesn't make much sense to run with
// more than 4M or with swap enabled.
void *start;
int num_pages = 1030;
int num;
start = dosbrk(PAGE_SIZE);
for (num = 1; num <= num_pages; num++) {
TEST161_LPROGRESS(num);
start = dosbrk(num*PAGE_SIZE);
markpagelight(start, num-1);
checkpagelight(start, num-1, true);
dosbrk(-(num*PAGE_SIZE));
}
success(TEST161_SUCCESS, SECRET, "/testbin/sbrktest");
}
/*
* Allocate all memory at once.
*
* This works by trying successively smaller sizes until one succeeds.
* Note that if you allow arbitrary swap overcommit this test will run
* the system out of swap. If this kills the system that's probably ok
* (check with your course staff, but handing OOM is difficult and
* probably not worth the time it would take you)... but ideally no
* one process is allowed to get big enough to do this.
*
* The recommended behavior is to set the process's maximum heap size
* to the amount of available RAM + swap that can be used at once.
* Because the test uses powers of two, this doesn't have to be very
* precise (e.g. counting the size of the non-heap parts of the
* process probably doesn't matter unless you're very unlucky) and
* isn't very difficult.
*
* Another option is to disallow swap overcommit, in which case you
* have sbrk try to reserve swap pages for each allocation, which will
* fail for huge allocations. The problem with this in practice is
* that you end up needing a huge swap disk even to run relatively
* small workloads, and then this test takes forever to run.
*/
static
void
test9(void)
{
size_t size;
unsigned i, pages, dot;
void *p;
bool bad;
#define HUGESIZE (1024 * 1024 * 1024) /* 1G */
tprintf("Checking how much memory we can allocate:\n");
for (size = HUGESIZE; (p = sbrk(size)) == (void *)-1; size = size/2) {
tprintf(" %9lu bytes: failed\n", (unsigned long) size);
}
tprintf(" %9lu bytes: succeeded\n", (unsigned long) size);
tprintf("Passed sbrk test 9 (part 1/5)\n");
tprintf("Touching each page.\n");
pages = size / PAGE_SIZE;
dot = pages / 64;
for (i=0; i<pages; i++) {
markpagelight(p, i);
if (dot > 0) {
TEST161_LPROGRESS_N(i, dot);
}
}
if (dot > 0) {
printf("\n");
}
tprintf("Testing each page.\n");
bad = false;
for (i=0; i<pages; i++) {
if (checkpagelight(p, i, dot > 0)) {
if (dot > 0) {
tprintf("\n");
}
warnx("FAILED: data corrupt");
bad = true;
}
if (dot > 0) {
TEST161_LPROGRESS_N(i, dot);
}
}
if (dot > 0) {
printf("\n");
}
if (bad) {
exit(1);
}
tprintf("Passed sbrk test 9 (part 2/5)\n");
tprintf("Freeing the memory.\n");
(void)dosbrk(-size);
tprintf("Passed sbrk test 9 (part 3/5)\n");
tprintf("Allocating the memory again.\n");
(void)dosbrk(size);
tprintf("Passed sbrk test 9 (part 4/5)\n");
tprintf("And really freeing it.\n");
(void)dosbrk(-size);
tprintf("Passed sbrk test 9 (all)\n");
success(TEST161_SUCCESS, SECRET, "/testbin/sbrktest");
}
static
void
stresstest(unsigned long seed, bool large)
{
const unsigned loops = 10000;
const unsigned dot = 200;
void *op;
unsigned num;
unsigned i, j, pages;
unsigned long r;
bool bad, neg;
srandom(seed);
tprintf("Seeded random number generator with %lu.\n", seed);
op = dosbrk(0);
bad = false;
num = 0;
for (i=0; i<loops; i++) {
/*
* The goal of this test is not to stress the VM system
* by thrashing swap (other tests do that) but by running
* the sbrk code a lot. So, clamp the total size at either
* 128K or 512K, which is 32 or 128 pages respectively.
*/
r = random();
pages = r % (large ? 32 : 8);
neg = pages <= num && ((r & 128) == 0);
if (!neg && num + pages > (large ? 128 : 32)) {
neg = 1;
}
// if(neg == 1)
// tprintf("neg is %d \n", neg);
if (neg) {
dosbrk(-(pages * PAGE_SIZE));
num -= pages;
}
else {
dosbrk(pages * PAGE_SIZE);
for (j=0; j<pages; j++) {
markpagelight(op, num + j);
}
num += pages;
}
for (j=0; j<num; j++) {
if (checkpagelight(op, j, true)) {
tprintf("\n");
tprintf("neg : %d \n", neg);
warnx("FAILED: data corrupt on page %u", j);
bad = true;
}
}
TEST161_LPROGRESS_N(i, dot);
}
printf("\n");
if (bad) {
warnx("FAILED");
exit(1);
}
dosbrk(-(num * PAGE_SIZE));
tprintf("Passed sbrk %s stress test.\n", large ? "large" : "small");
success(TEST161_SUCCESS, SECRET, "/testbin/sbrktest");
}