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