1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright 2015, Michael Neuling, IBM Corp.
4 * Original: Michael Neuling 19/7/2013
5 * Edited: Rashmica Gupta 01/12/2015
6 *
7 * Do some transactions, see if the tar is corrupted.
8 * If the transaction is aborted, the TAR should be rolled back to the
9 * checkpointed value before the transaction began. The value written to
10 * TAR in suspended mode should only remain in TAR if the transaction
11 * completes.
12 */
13
14 #include <stdio.h>
15 #include <stdlib.h>
16 #include <unistd.h>
17 #include <string.h>
18
19 #include "tm.h"
20 #include "utils.h"
21
22 int num_loops = 10000;
23
24 int test_tar(void)
25 {
26 int i;
27
28 SKIP_IF(!have_htm());
29 SKIP_IF(!is_ppc64le());
30
31 for (i = 0; i < num_loops; i++)
32 {
33 uint64_t result = 0;
34 asm __volatile__(
35 "li 7, 1;"
36 "mtspr %[tar], 7;" /* tar = 1 */
37 "tbegin.;"
38 "beq 3f;"
39 "li 4, 0x7000;" /* Loop lots, to use time */
40 "2:;" /* Start loop */
41 "li 7, 2;"
42 "mtspr %[tar], 7;" /* tar = 2 */
43 "tsuspend.;"
44 "li 7, 3;"
45 "mtspr %[tar], 7;" /* tar = 3 */
46 "tresume.;"
47 "subi 4, 4, 1;"
48 "cmpdi 4, 0;"
49 "bne 2b;"
50 "tend.;"
51
52 /* Transaction sucess! TAR should be 3 */
53 "mfspr 7, %[tar];"
54 "ori %[res], 7, 4;" // res = 3|4 = 7
55 "b 4f;"
56
57 /* Abort handler. TAR should be rolled back to 1 */
58 "3:;"
59 "mfspr 7, %[tar];"
60 "ori %[res], 7, 8;" // res = 1|8 = 9
61 "4:;"
62
63 : [res]"=r"(result)
64 : [tar]"i"(SPRN_TAR)
65 : "memory", "r0", "r4", "r7");
66
67 /* If result is anything else other than 7 or 9, the tar
68 * value must have been corrupted. */
69 if ((result != 7) && (result != 9))
70 return 1;
71 }
72 return 0;
73 }
74
75 int main(int argc, char *argv[])
76 {
77 /* A low number of iterations (eg 100) can cause a false pass */
78 if (argc > 1) {
79 if (strcmp(argv[1], "-h") == 0) {
80 printf("Syntax:\n\t%s [<num loops>]\n",
81 argv[0]);
82 return 1;
83 } else {
84 num_loops = atoi(argv[1]);
85 }
86 }
87
88 printf("Starting, %d loops\n", num_loops);
89
90 return test_harness(test_tar, "tm_tar");
91 }