1 #include <pthread.h>
2 #include <stdlib.h>
3 #include <stdio.h>
4 #include <unistd.h>
5
6 #include <mach/mach.h>
7 #include <mach/mach_vm.h>
8
9 static void*
loop(void * arg)10 loop(__attribute__ ((unused)) void *arg)
11 {
12 while (1) {
13 }
14 }
15
16
17 static int
run_additional_threads(int nthreads)18 run_additional_threads(int nthreads)
19 {
20 for (int i = 0; i < nthreads; i++) {
21 pthread_t pthread;
22 int err;
23
24 err = pthread_create(&pthread, NULL, loop, NULL);
25 if (err) {
26 return err;
27 }
28 }
29
30 return 0;
31 }
32
33 static int
allocate_and_wire_memory(mach_vm_size_t size)34 allocate_and_wire_memory(mach_vm_size_t size)
35 {
36 int err;
37 task_t task = mach_task_self();
38 mach_vm_address_t addr;
39
40 if (size <= 0) {
41 return 0;
42 }
43
44 err = mach_vm_allocate(task, &addr, size, VM_FLAGS_ANYWHERE);
45 if (err != KERN_SUCCESS) {
46 printf("mach_vm_allocate returned non-zero: %s\n", mach_error_string(err));
47 return err;
48 }
49 err = mach_vm_protect(task, addr, size, 0, VM_PROT_READ | VM_PROT_WRITE);
50 if (err != KERN_SUCCESS) {
51 printf("mach_vm_protect returned non-zero: %s\n", mach_error_string(err));
52 return err;
53 }
54 host_t host_priv_port;
55 err = host_get_host_priv_port(mach_host_self(), &host_priv_port);
56 if (err != KERN_SUCCESS) {
57 printf("host_get_host_priv_port returned non-zero: %s\n", mach_error_string(err));
58 return err;
59 }
60 err = mach_vm_wire(host_priv_port, task, addr, size, VM_PROT_READ | VM_PROT_WRITE);
61 if (err != KERN_SUCCESS) {
62 printf("mach_vm_wire returned non-zero: %s\n", mach_error_string(err));
63 return err;
64 }
65
66 return 0;
67 }
68
69 int
main(int argc,char * argv[])70 main(int argc, char *argv[])
71 {
72 int nthreads = 0;
73 int err;
74 mach_vm_size_t wired_mem = 0;
75
76 if (argc > 1) {
77 nthreads = (int)strtoul(argv[1], NULL, 10);
78 }
79 if (argc > 2) {
80 wired_mem = (mach_vm_size_t)strtoul(argv[2], NULL, 10);
81 }
82
83 err = allocate_and_wire_memory(wired_mem);
84 if (err) {
85 return err;
86 }
87
88 err = run_additional_threads(nthreads);
89 if (err) {
90 return err;
91 }
92
93 return 0;
94 }
95