1 /* libunwind - a platform-independent unwind library
2    Copyright (C) 2004 Hewlett-Packard Co
3 	Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
4 
5 This file is part of libunwind.
6 
7 Permission is hereby granted, free of charge, to any person obtaining
8 a copy of this software and associated documentation files (the
9 "Software"), to deal in the Software without restriction, including
10 without limitation the rights to use, copy, modify, merge, publish,
11 distribute, sublicense, and/or sell copies of the Software, and to
12 permit persons to whom the Software is furnished to do so, subject to
13 the following conditions:
14 
15 The above copyright notice and this permission notice shall be
16 included in all copies or substantial portions of the Software.
17 
18 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
21 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
22 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
23 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
24 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
25 
26 /* This program creates lots of mappings such that on Linux the
27    reading of /proc/PID/maps gets very slow.  With proper caching,
28    test-ptrace should still run at acceptable speed once
29    /proc/PID/maps has been scanned.  If the program dies with a
30    SIGALRM, it means it was running unexpectedly slow.  */
31 
32 #include <signal.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <unistd.h>
36 
37 #include <sys/mman.h>
38 
39 #if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
40 # define MAP_ANONYMOUS MAP_ANON
41 #endif
42 
43 int
main(void)44 main (void)
45 {
46   long n = 0;
47 
48   signal (SIGUSR1, SIG_IGN);
49   signal (SIGUSR2, SIG_IGN);
50 
51   printf ("Starting mmap test...\n");
52   for (n = 0; n < 30000; ++n)
53     {
54       if (mmap (NULL, 1, (n & 1) ? PROT_READ : PROT_WRITE,
55 		MAP_PRIVATE | MAP_ANONYMOUS | MAP_NORESERVE,
56 		-1, 0) == MAP_FAILED)
57 	{
58 	  printf ("Failed after %ld successful maps\n", n - 1);
59 	  exit (0);
60 	}
61     }
62 
63   alarm (80);	/* die if we don't finish in 80 seconds */
64 
65   printf ("Turning on single-stepping...\n");
66   kill (getpid (), SIGUSR1);	/* tell test-ptrace to start single-stepping */
67   printf ("Va bene?\n");
68   kill (getpid (), SIGUSR2);	/* tell test-ptrace to stop single-stepping */
69   printf ("Turned single-stepping off...\n");
70   return 0;
71 }
72