49 lines
1 KiB
C
49 lines
1 KiB
C
// Demonstrate that moving the "acquire" in iderw after the loop that
|
|
// appends to the idequeue results in a race.
|
|
|
|
// For this to work, you should also add a spin within iderw's
|
|
// idequeue traversal loop. Adding the following demonstrated a panic
|
|
// after about 5 runs of stressfs in QEMU on a 2.1GHz CPU:
|
|
// for (i = 0; i < 40000; i++)
|
|
// asm volatile("");
|
|
|
|
#include "kernel/types.h"
|
|
#include "kernel/stat.h"
|
|
#include "user/user.h"
|
|
#include "kernel/fs.h"
|
|
#include "kernel/fcntl.h"
|
|
|
|
int
|
|
main(int argc, char *argv[])
|
|
{
|
|
int fd, i;
|
|
char path[] = "stressfs0";
|
|
char data[512];
|
|
|
|
printf(1, "stressfs starting\n");
|
|
memset(data, 'a', sizeof(data));
|
|
|
|
for(i = 0; i < 4; i++)
|
|
if(fork() > 0)
|
|
break;
|
|
|
|
printf(1, "write %d\n", i);
|
|
|
|
path[8] += i;
|
|
fd = open(path, O_CREATE | O_RDWR);
|
|
for(i = 0; i < 20; i++)
|
|
// printf(fd, "%d\n", i);
|
|
write(fd, data, sizeof(data));
|
|
close(fd);
|
|
|
|
printf(1, "read\n");
|
|
|
|
fd = open(path, O_RDONLY);
|
|
for (i = 0; i < 20; i++)
|
|
read(fd, data, sizeof(data));
|
|
close(fd);
|
|
|
|
wait();
|
|
|
|
exit();
|
|
}
|