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