71 lines
1.6 KiB
C
71 lines
1.6 KiB
C
#define _GNU_SOURCE
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#include <stdlib.h>
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#include <stdio.h>
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#include <string.h>
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#include <sys/types.h>
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#include <unistd.h>
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#include <sys/wait.h>
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#include <sched.h>
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int fork(void);
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volatile unsigned long counter = 0;
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void cpu_intensive_work(const char *process_name) {
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printf("%s (PID: %d) starting CPU-intensive work on CPU %d\n", process_name, getpid(), sched_getcpu());
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while (1) {
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counter++;
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counter = (counter * counter + counter) % (counter * 1023);
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}
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}
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void print_usage(const char *prog) {
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fprintf(stderr, "Usage: %s [--single] [--dual]\n", prog);
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fprintf(stderr, " --single Run single process (default)\n");
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fprintf(stderr, " --dual Run two processes\n");
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}
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int main(int argc, char *argv[]) {
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int use_dual = 0;
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if (argc > 1) {
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if (strcmp(argv[1], "--dual") == 0) {
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use_dual = 1;
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} else if (strcmp(argv[1], "--single") == 0) {
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use_dual = 0;
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} else {
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fprintf(stderr, "Unknown option: %s\n", argv[1]);
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print_usage(argv[0]);
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return 1;
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}
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}
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if (use_dual) {
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// Dual-process mode
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pid_t pid = fork();
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if (pid == 0) {
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cpu_intensive_work("Child process");
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exit(0);
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} else if (pid > 0) {
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cpu_intensive_work("Parent process");
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wait(NULL);
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return 0;
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} else {
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perror("fork failed");
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return 1;
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}
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} else {
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// Single-process mode
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cpu_intensive_work("Process");
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}
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return 0;
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}
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