1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright 2016, Cyril Bur, IBM Corp. |
4 | * |
5 | * Test the kernel's signal frame code. |
6 | * |
7 | * The kernel sets up two sets of ucontexts if the signal was to be |
8 | * delivered while the thread was in a transaction (referred too as |
9 | * first and second contexts). |
10 | * Expected behaviour is that the checkpointed state is in the user |
11 | * context passed to the signal handler (first context). The speculated |
12 | * state can be accessed with the uc_link pointer (second context). |
13 | * |
14 | * The rationale for this is that if TM unaware code (which linked |
15 | * against TM libs) installs a signal handler it will not know of the |
16 | * speculative nature of the 'live' registers and may infer the wrong |
17 | * thing. |
18 | */ |
19 | |
20 | #include <stdlib.h> |
21 | #include <stdio.h> |
22 | #include <signal.h> |
23 | #include <unistd.h> |
24 | |
25 | #include <altivec.h> |
26 | |
27 | #include "utils.h" |
28 | #include "tm.h" |
29 | |
30 | #define MAX_ATTEMPT 500000 |
31 | |
32 | #define NV_FPU_REGS 18 /* Number of non-volatile FP registers */ |
33 | #define FPR14 14 /* First non-volatile FP register to check in f14-31 subset */ |
34 | |
35 | long tm_signal_self_context_load(pid_t pid, long *gprs, double *fps, vector int *vms, vector int *vss); |
36 | |
37 | /* Test only non-volatile registers, i.e. 18 fpr registers from f14 to f31 */ |
38 | static double fps[] = { |
39 | /* First context will be set with these values, i.e. non-speculative */ |
40 | 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, |
41 | /* Second context will be set with these values, i.e. speculative */ |
42 | -1,-2,-3,-4,-5,-6,-7,-8,-9,-10,-11,-12,-13,-14,-15,-16,-17,-18 |
43 | }; |
44 | |
45 | static sig_atomic_t fail, broken; |
46 | |
47 | static void signal_usr1(int signum, siginfo_t *info, void *uc) |
48 | { |
49 | int i; |
50 | ucontext_t *ucp = uc; |
51 | ucontext_t *tm_ucp = ucp->uc_link; |
52 | |
53 | for (i = 0; i < NV_FPU_REGS; i++) { |
54 | /* Check first context. Print all mismatches. */ |
55 | fail = (ucp->uc_mcontext.fp_regs[FPR14 + i] != fps[i]); |
56 | if (fail) { |
57 | broken = 1; |
58 | printf("FPR%d (1st context) == %g instead of %g (expected)\n" , |
59 | FPR14 + i, ucp->uc_mcontext.fp_regs[FPR14 + i], fps[i]); |
60 | } |
61 | } |
62 | |
63 | for (i = 0; i < NV_FPU_REGS; i++) { |
64 | /* Check second context. Print all mismatches. */ |
65 | fail = (tm_ucp->uc_mcontext.fp_regs[FPR14 + i] != fps[NV_FPU_REGS + i]); |
66 | if (fail) { |
67 | broken = 1; |
68 | printf("FPR%d (2nd context) == %g instead of %g (expected)\n" , |
69 | FPR14 + i, tm_ucp->uc_mcontext.fp_regs[FPR14 + i], fps[NV_FPU_REGS + i]); |
70 | } |
71 | } |
72 | } |
73 | |
74 | static int tm_signal_context_chk_fpu() |
75 | { |
76 | struct sigaction act; |
77 | int i; |
78 | long rc; |
79 | pid_t pid = getpid(); |
80 | |
81 | SKIP_IF(!have_htm()); |
82 | SKIP_IF(htm_is_synthetic()); |
83 | |
84 | act.sa_sigaction = signal_usr1; |
85 | sigemptyset(&act.sa_mask); |
86 | act.sa_flags = SA_SIGINFO; |
87 | if (sigaction(SIGUSR1, &act, NULL) < 0) { |
88 | perror("sigaction sigusr1" ); |
89 | exit(1); |
90 | } |
91 | |
92 | i = 0; |
93 | while (i < MAX_ATTEMPT && !broken) { |
94 | /* |
95 | * tm_signal_self_context_load will set both first and second |
96 | * contexts accordingly to the values passed through non-NULL |
97 | * array pointers to it, in that case 'fps', and invoke the |
98 | * signal handler installed for SIGUSR1. |
99 | */ |
100 | rc = tm_signal_self_context_load(pid, NULL, fps, NULL, NULL); |
101 | FAIL_IF(rc != pid); |
102 | i++; |
103 | } |
104 | |
105 | return (broken); |
106 | } |
107 | |
108 | int main(void) |
109 | { |
110 | return test_harness(tm_signal_context_chk_fpu, "tm_signal_context_chk_fpu" ); |
111 | } |
112 | |