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_GPR_REGS 18 /* Number of non-volatile GPR registers */ |
33 | #define R14 14 /* First non-volatile register to check in r14-r31 subset */ |
34 | |
35 | long tm_signal_self_context_load(pid_t pid, long *gprs, double *fps, vector int *vms, vector int *vss); |
36 | |
37 | static sig_atomic_t fail, broken; |
38 | |
39 | /* Test only non-volatile general purpose registers, i.e. r14-r31 */ |
40 | static long gprs[] = { |
41 | /* First context will be set with these values, i.e. non-speculative */ |
42 | /* R14, R15, ... */ |
43 | 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, |
44 | /* Second context will be set with these values, i.e. speculative */ |
45 | /* R14, R15, ... */ |
46 | -1,-2,-3,-4,-5,-6,-7,-8,-9,-10,-11,-12,-13,-14,-15,-16,-17,-18 |
47 | }; |
48 | |
49 | static void signal_usr1(int signum, siginfo_t *info, void *uc) |
50 | { |
51 | int i; |
52 | ucontext_t *ucp = uc; |
53 | ucontext_t *tm_ucp = ucp->uc_link; |
54 | |
55 | /* Check first context. Print all mismatches. */ |
56 | for (i = 0; i < NV_GPR_REGS; i++) { |
57 | fail = (ucp->uc_mcontext.gp_regs[R14 + i] != gprs[i]); |
58 | if (fail) { |
59 | broken = 1; |
60 | printf("GPR%d (1st context) == %lu instead of %lu (expected)\n" , |
61 | R14 + i, ucp->uc_mcontext.gp_regs[R14 + i], gprs[i]); |
62 | } |
63 | } |
64 | |
65 | /* Check second context. Print all mismatches. */ |
66 | for (i = 0; i < NV_GPR_REGS; i++) { |
67 | fail = (tm_ucp->uc_mcontext.gp_regs[R14 + i] != gprs[NV_GPR_REGS + i]); |
68 | if (fail) { |
69 | broken = 1; |
70 | printf("GPR%d (2nd context) == %lu instead of %lu (expected)\n" , |
71 | R14 + i, tm_ucp->uc_mcontext.gp_regs[R14 + i], gprs[NV_GPR_REGS + i]); |
72 | } |
73 | } |
74 | } |
75 | |
76 | static int tm_signal_context_chk_gpr() |
77 | { |
78 | struct sigaction act; |
79 | int i; |
80 | long rc; |
81 | pid_t pid = getpid(); |
82 | |
83 | SKIP_IF(!have_htm()); |
84 | SKIP_IF(htm_is_synthetic()); |
85 | |
86 | act.sa_sigaction = signal_usr1; |
87 | sigemptyset(&act.sa_mask); |
88 | act.sa_flags = SA_SIGINFO; |
89 | if (sigaction(SIGUSR1, &act, NULL) < 0) { |
90 | perror("sigaction sigusr1" ); |
91 | exit(1); |
92 | } |
93 | |
94 | i = 0; |
95 | while (i < MAX_ATTEMPT && !broken) { |
96 | /* |
97 | * tm_signal_self_context_load will set both first and second |
98 | * contexts accordingly to the values passed through non-NULL |
99 | * array pointers to it, in that case 'gprs', and invoke the |
100 | * signal handler installed for SIGUSR1. |
101 | */ |
102 | rc = tm_signal_self_context_load(pid, gprs, NULL, NULL, NULL); |
103 | FAIL_IF(rc != pid); |
104 | i++; |
105 | } |
106 | |
107 | return broken; |
108 | } |
109 | |
110 | int main(void) |
111 | { |
112 | return test_harness(tm_signal_context_chk_gpr, "tm_signal_context_chk_gpr" ); |
113 | } |
114 | |