1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2015, Sam Bobroff, IBM Corp.
4  *
5  * Test the kernel's system call code to ensure that a system call
6  * made from within an active HTM transaction is aborted with the
7  * correct failure code.
8  * Conversely, ensure that a system call made from within a
9  * suspended transaction can succeed.
10  */
11 
12 #include <stdio.h>
13 #include <unistd.h>
14 #include <sys/syscall.h>
15 #include <asm/tm.h>
16 #include <sys/time.h>
17 #include <stdlib.h>
18 
19 #include "utils.h"
20 #include "tm.h"
21 
22 #ifndef PPC_FEATURE2_SCV
23 #define PPC_FEATURE2_SCV               0x00100000 /* scv syscall */
24 #endif
25 
26 extern int getppid_tm_active(void);
27 extern int getppid_tm_suspended(void);
28 extern int getppid_scv_tm_active(void);
29 extern int getppid_scv_tm_suspended(void);
30 
31 unsigned retries = 0;
32 
33 #define TEST_DURATION 10 /* seconds */
34 
35 pid_t getppid_tm(bool scv, bool suspend)
36 {
37 	int i;
38 	pid_t pid;
39 
40 	for (i = 0; i < TM_RETRIES; i++) {
41 		if (suspend) {
42 			if (scv)
43 				pid = getppid_scv_tm_suspended();
44 			else
45 				pid = getppid_tm_suspended();
46 		} else {
47 			if (scv)
48 				pid = getppid_scv_tm_active();
49 			else
50 				pid = getppid_tm_active();
51 		}
52 
53 		if (pid >= 0)
54 			return pid;
55 
56 		if (failure_is_persistent()) {
57 			if (failure_is_syscall())
58 				return -1;
59 
60 			printf("Unexpected persistent transaction failure.\n");
61 			printf("TEXASR 0x%016lx, TFIAR 0x%016lx.\n",
62 			       __builtin_get_texasr(), __builtin_get_tfiar());
63 			exit(-1);
64 		}
65 
66 		retries++;
67 	}
68 
69 	printf("Exceeded limit of %d temporary transaction failures.\n", TM_RETRIES);
70 	printf("TEXASR 0x%016lx, TFIAR 0x%016lx.\n",
71 	       __builtin_get_texasr(), __builtin_get_tfiar());
72 
73 	exit(-1);
74 }
75 
76 int tm_syscall(void)
77 {
78 	unsigned count = 0;
79 	struct timeval end, now;
80 
81 	SKIP_IF(!have_htm_nosc());
82 	SKIP_IF(htm_is_synthetic());
83 
84 	setbuf(stdout, NULL);
85 
86 	printf("Testing transactional syscalls for %d seconds...\n", TEST_DURATION);
87 
88 	gettimeofday(&end, NULL);
89 	now.tv_sec = TEST_DURATION;
90 	now.tv_usec = 0;
91 	timeradd(&end, &now, &end);
92 
93 	for (count = 0; timercmp(&now, &end, <); count++) {
94 		/*
95 		 * Test a syscall within a suspended transaction and verify
96 		 * that it succeeds.
97 		 */
98 		FAIL_IF(getppid_tm(false, true) == -1); /* Should succeed. */
99 
100 		/*
101 		 * Test a syscall within an active transaction and verify that
102 		 * it fails with the correct failure code.
103 		 */
104 		FAIL_IF(getppid_tm(false, false) != -1);  /* Should fail... */
105 		FAIL_IF(!failure_is_persistent()); /* ...persistently... */
106 		FAIL_IF(!failure_is_syscall());    /* ...with code syscall. */
107 
108 		/* Now do it all again with scv if it is available. */
109 		if (have_hwcap2(PPC_FEATURE2_SCV)) {
110 			FAIL_IF(getppid_tm(true, true) == -1); /* Should succeed. */
111 			FAIL_IF(getppid_tm(true, false) != -1);  /* Should fail... */
112 			FAIL_IF(!failure_is_persistent()); /* ...persistently... */
113 			FAIL_IF(!failure_is_syscall());    /* ...with code syscall. */
114 		}
115 
116 		gettimeofday(&now, 0);
117 	}
118 
119 	printf("%d active and suspended transactions behaved correctly.\n", count);
120 	printf("(There were %d transaction retries.)\n", retries);
121 
122 	return 0;
123 }
124 
125 int main(void)
126 {
127 	return test_harness(tm_syscall, "tm_syscall");
128 }
129