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 extern int getppid_tm_active(void);
23 extern int getppid_tm_suspended(void);
24 
25 unsigned retries = 0;
26 
27 #define TEST_DURATION 10 /* seconds */
28 #define TM_RETRIES 100
29 
30 pid_t getppid_tm(bool suspend)
31 {
32 	int i;
33 	pid_t pid;
34 
35 	for (i = 0; i < TM_RETRIES; i++) {
36 		if (suspend)
37 			pid = getppid_tm_suspended();
38 		else
39 			pid = getppid_tm_active();
40 
41 		if (pid >= 0)
42 			return pid;
43 
44 		if (failure_is_persistent()) {
45 			if (failure_is_syscall())
46 				return -1;
47 
48 			printf("Unexpected persistent transaction failure.\n");
49 			printf("TEXASR 0x%016lx, TFIAR 0x%016lx.\n",
50 			       __builtin_get_texasr(), __builtin_get_tfiar());
51 			exit(-1);
52 		}
53 
54 		retries++;
55 	}
56 
57 	printf("Exceeded limit of %d temporary transaction failures.\n", TM_RETRIES);
58 	printf("TEXASR 0x%016lx, TFIAR 0x%016lx.\n",
59 	       __builtin_get_texasr(), __builtin_get_tfiar());
60 
61 	exit(-1);
62 }
63 
64 int tm_syscall(void)
65 {
66 	unsigned count = 0;
67 	struct timeval end, now;
68 
69 	SKIP_IF(!have_htm_nosc());
70 
71 	setbuf(stdout, NULL);
72 
73 	printf("Testing transactional syscalls for %d seconds...\n", TEST_DURATION);
74 
75 	gettimeofday(&end, NULL);
76 	now.tv_sec = TEST_DURATION;
77 	now.tv_usec = 0;
78 	timeradd(&end, &now, &end);
79 
80 	for (count = 0; timercmp(&now, &end, <); count++) {
81 		/*
82 		 * Test a syscall within a suspended transaction and verify
83 		 * that it succeeds.
84 		 */
85 		FAIL_IF(getppid_tm(true) == -1); /* Should succeed. */
86 
87 		/*
88 		 * Test a syscall within an active transaction and verify that
89 		 * it fails with the correct failure code.
90 		 */
91 		FAIL_IF(getppid_tm(false) != -1);  /* Should fail... */
92 		FAIL_IF(!failure_is_persistent()); /* ...persistently... */
93 		FAIL_IF(!failure_is_syscall());    /* ...with code syscall. */
94 		gettimeofday(&now, 0);
95 	}
96 
97 	printf("%d active and suspended transactions behaved correctly.\n", count);
98 	printf("(There were %d transaction retries.)\n", retries);
99 
100 	return 0;
101 }
102 
103 int main(void)
104 {
105 	return test_harness(tm_syscall, "tm_syscall");
106 }
107