1 /*
2  * Copyright 2015, Michael Neuling, IBM Corp.
3  * Licensed under GPLv2.
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 }
92