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// 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 "types.h"
#include "stat.h"
#include "user.h"
#include "fs.h"
#include "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();
}
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