sewardj | b411202 | 2007-11-09 22:49:28 +0000 | [diff] [blame] | 1 | |
| 2 | /* FIXME: this is basically a bad test as it is scheduling- |
| 3 | sensitive. Sometimes the output is: |
| 4 | |
| 5 | child: new value 6 |
| 6 | child: new value 10 |
| 7 | done, x = 10 |
| 8 | |
| 9 | and sometimes |
| 10 | |
| 11 | child: new value 10 |
| 12 | done, x = 10 |
| 13 | */ |
| 14 | |
| 15 | #include <pthread.h> |
| 16 | #include <stdio.h> |
| 17 | #include <stdlib.h> |
| 18 | #include <unistd.h> |
| 19 | |
| 20 | /* Simple test program, no race. Parent writes atomically to a counter |
| 21 | whilst child reads it. When counter reaches a prearranged value, |
| 22 | child joins back to parent. Parent (writer) uses hardware bus lock; |
| 23 | child is only reading and so does not need to use a bus lock. */ |
| 24 | |
sewardj | 8777f73 | 2010-01-02 10:43:23 +0000 | [diff] [blame] | 25 | #undef PLAT_x86_darwin |
| 26 | #undef PLAT_amd64_darwin |
sewardj | b411202 | 2007-11-09 22:49:28 +0000 | [diff] [blame] | 27 | #undef PLAT_x86_linux |
| 28 | #undef PLAT_amd64_linux |
| 29 | #undef PLAT_ppc32_linux |
| 30 | #undef PLAT_ppc64_linux |
sewardj | 8777f73 | 2010-01-02 10:43:23 +0000 | [diff] [blame] | 31 | #undef PLAT_arm_linux |
sewardj | b5b8740 | 2011-03-07 16:05:35 +0000 | [diff] [blame] | 32 | #undef PLAT_s390x_linux |
sewardj | 5db1540 | 2012-06-07 09:13:21 +0000 | [diff] [blame] | 33 | #undef PLAT_mips32_linux |
sewardj | b411202 | 2007-11-09 22:49:28 +0000 | [diff] [blame] | 34 | |
sewardj | 6e9de46 | 2011-06-28 07:25:29 +0000 | [diff] [blame] | 35 | #if defined(__APPLE__) && defined(__i386__) |
sewardj | 8777f73 | 2010-01-02 10:43:23 +0000 | [diff] [blame] | 36 | # define PLAT_x86_darwin 1 |
| 37 | #elif defined(__APPLE__) && defined(__x86_64__) |
| 38 | # define PLAT_amd64_darwin 1 |
| 39 | #elif defined(__linux__) && defined(__i386__) |
| 40 | # define PLAT_x86_linux 1 |
| 41 | #elif defined(__linux__) && defined(__x86_64__) |
| 42 | # define PLAT_amd64_linux 1 |
| 43 | #elif defined(__linux__) && defined(__powerpc__) && !defined(__powerpc64__) |
| 44 | # define PLAT_ppc32_linux 1 |
| 45 | #elif defined(__linux__) && defined(__powerpc__) && defined(__powerpc64__) |
| 46 | # define PLAT_ppc64_linux 1 |
| 47 | #elif defined(__linux__) && defined(__arm__) |
| 48 | # define PLAT_arm_linux 1 |
sewardj | b5b8740 | 2011-03-07 16:05:35 +0000 | [diff] [blame] | 49 | #elif defined(__linux__) && defined(__s390x__) |
| 50 | # define PLAT_s390x_linux 1 |
sewardj | 5db1540 | 2012-06-07 09:13:21 +0000 | [diff] [blame] | 51 | #elif defined(__linux__) && defined(__mips__) |
| 52 | # define PLAT_mips32_linux 1 |
sewardj | b411202 | 2007-11-09 22:49:28 +0000 | [diff] [blame] | 53 | #endif |
| 54 | |
sewardj | 8777f73 | 2010-01-02 10:43:23 +0000 | [diff] [blame] | 55 | |
sewardj | f5b5f84 | 2010-01-04 10:47:25 +0000 | [diff] [blame] | 56 | #if defined(PLAT_amd64_linux) || defined(PLAT_x86_linux) \ |
| 57 | || defined(PLAT_amd64_darwin) || defined(PLAT_x86_darwin) |
sewardj | 2ee3395 | 2007-11-27 11:23:55 +0000 | [diff] [blame] | 58 | # define INC(_lval,_lqual) \ |
sewardj | b411202 | 2007-11-09 22:49:28 +0000 | [diff] [blame] | 59 | __asm__ __volatile__ ( \ |
| 60 | "lock ; incl (%0)" : /*out*/ : /*in*/"r"(&(_lval)) : "memory", "cc" ) |
sewardj | 6e9de46 | 2011-06-28 07:25:29 +0000 | [diff] [blame] | 61 | #elif defined(PLAT_ppc32_linux) || defined(PLAT_ppc64_linux) |
sewardj | 2ee3395 | 2007-11-27 11:23:55 +0000 | [diff] [blame] | 62 | # define INC(_lval,_lqual) \ |
sewardj | b411202 | 2007-11-09 22:49:28 +0000 | [diff] [blame] | 63 | __asm__ __volatile__( \ |
sewardj | d12c4a5 | 2011-03-28 08:37:19 +0000 | [diff] [blame] | 64 | "1:\n" \ |
sewardj | b411202 | 2007-11-09 22:49:28 +0000 | [diff] [blame] | 65 | " lwarx 15,0,%0\n" \ |
| 66 | " addi 15,15,1\n" \ |
| 67 | " stwcx. 15,0,%0\n" \ |
sewardj | d12c4a5 | 2011-03-28 08:37:19 +0000 | [diff] [blame] | 68 | " bne- 1b\n" \ |
sewardj | b411202 | 2007-11-09 22:49:28 +0000 | [diff] [blame] | 69 | : /*out*/ : /*in*/ "b"(&(_lval)) \ |
| 70 | : /*trash*/ "r15", "cr0", "memory" \ |
| 71 | ) |
sewardj | 8777f73 | 2010-01-02 10:43:23 +0000 | [diff] [blame] | 72 | #elif defined(PLAT_arm_linux) |
| 73 | # define INC(_lval,_lqual) \ |
| 74 | __asm__ __volatile__( \ |
sewardj | d12c4a5 | 2011-03-28 08:37:19 +0000 | [diff] [blame] | 75 | "1:\n" \ |
sewardj | 8777f73 | 2010-01-02 10:43:23 +0000 | [diff] [blame] | 76 | " ldrex r8, [%0, #0]\n" \ |
| 77 | " add r8, r8, #1\n" \ |
| 78 | " strex r9, r8, [%0, #0]\n" \ |
| 79 | " cmp r9, #0\n" \ |
sewardj | d12c4a5 | 2011-03-28 08:37:19 +0000 | [diff] [blame] | 80 | " bne 1b\n" \ |
sewardj | 8777f73 | 2010-01-02 10:43:23 +0000 | [diff] [blame] | 81 | : /*out*/ : /*in*/ "r"(&(_lval)) \ |
| 82 | : /*trash*/ "r8", "r9", "cc", "memory" \ |
| 83 | ); |
sewardj | b5b8740 | 2011-03-07 16:05:35 +0000 | [diff] [blame] | 84 | #elif defined(PLAT_s390x_linux) |
| 85 | # define INC(_lval,_lqual) \ |
| 86 | __asm__ __volatile__( \ |
| 87 | "1: l 0,%0\n" \ |
| 88 | " lr 1,0\n" \ |
| 89 | " ahi 1,1\n" \ |
| 90 | " cs 0,1,%0\n" \ |
| 91 | " jl 1b\n" \ |
| 92 | : "+m" (_lval) :: "cc", "0","1" \ |
| 93 | ) |
sewardj | 5db1540 | 2012-06-07 09:13:21 +0000 | [diff] [blame] | 94 | #elif defined(PLAT_mips32_linux) |
| 95 | # define INC(_lval,_lqual) \ |
| 96 | __asm__ __volatile__ ( \ |
| 97 | "L1xyzzy1" _lqual":\n" \ |
| 98 | " move $8, %0\n" \ |
| 99 | " ll $9, 0($t0)\n" \ |
| 100 | " addi $9, $9, 1\n" \ |
| 101 | " sc $9, 0($t0)\n" \ |
| 102 | " li $10, 1\n" \ |
| 103 | " bne $9, $10, L1xyzzy1" _lqual \ |
| 104 | : /*out*/ : /*in*/ "r"(&(_lval)) \ |
| 105 | : /*trash*/ "$8", "$9", "$10", "cc", "memory" \ |
| 106 | ) |
sewardj | b411202 | 2007-11-09 22:49:28 +0000 | [diff] [blame] | 107 | #else |
| 108 | # error "Fix Me for this platform" |
| 109 | #endif |
| 110 | |
| 111 | |
| 112 | |
| 113 | #define LIMIT 10 |
| 114 | |
| 115 | volatile int x = 0; |
| 116 | |
| 117 | void* child_fn ( void* arg ) |
| 118 | { |
| 119 | int q = 0; |
| 120 | int oldx = 0; |
bart | f91fd73 | 2011-10-23 13:28:20 +0000 | [diff] [blame] | 121 | struct timespec ts = { 0, 1000 * 1000 }; |
| 122 | |
sewardj | b411202 | 2007-11-09 22:49:28 +0000 | [diff] [blame] | 123 | while (1) { |
| 124 | q = (x >= LIMIT); |
| 125 | if (x != oldx) { |
| 126 | oldx = x; |
| 127 | printf("child: new value %d\n", oldx); |
| 128 | fflush(stdout); |
| 129 | } |
| 130 | if (q) break; |
bart | f91fd73 | 2011-10-23 13:28:20 +0000 | [diff] [blame] | 131 | nanosleep(&ts, 0); |
sewardj | b411202 | 2007-11-09 22:49:28 +0000 | [diff] [blame] | 132 | } |
| 133 | return NULL; |
| 134 | } |
| 135 | |
| 136 | int main ( void ) |
| 137 | { |
| 138 | pthread_t child; |
| 139 | int i; |
| 140 | |
| 141 | if (pthread_create(&child, NULL, child_fn, NULL)) { |
| 142 | perror("pthread_create"); |
| 143 | exit(1); |
| 144 | } |
| 145 | |
| 146 | for (i = 0; i < LIMIT; i++) { |
sewardj | 2ee3395 | 2007-11-27 11:23:55 +0000 | [diff] [blame] | 147 | INC(x, "main"); |
sewardj | b411202 | 2007-11-09 22:49:28 +0000 | [diff] [blame] | 148 | if (i == 5) sleep(1); /* make sure child doesn't starve */ |
| 149 | } |
| 150 | |
sewardj | b411202 | 2007-11-09 22:49:28 +0000 | [diff] [blame] | 151 | if (pthread_join(child, NULL)) { |
| 152 | perror("pthread join"); |
| 153 | exit(1); |
| 154 | } |
| 155 | |
| 156 | printf("done, x = %d\n", x); |
| 157 | |
| 158 | return 0; |
| 159 | } |