tools/testing/selftests/powerpc/tm/tm-signal-context-chk-fpu.c

   1 /*
   2  * Copyright 2016, Cyril Bur, IBM Corp.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version
   7  * 2 of the License, or (at your option) any later version.
   8  *
   9  *
  10  * Test the kernel's signal frame code.
  11  *
  12  * The kernel sets up two sets of ucontexts if the signal was to be
  13  * delivered while the thread was in a transaction.
  14  * Expected behaviour is that the checkpointed state is in the user
  15  * context passed to the signal handler. The speculated state can be
  16  * accessed with the uc_link pointer.
  17  *
  18  * The rationale for this is that if TM unaware code (which linked
  19  * against TM libs) installs a signal handler it will not know of the
  20  * speculative nature of the 'live' registers and may infer the wrong
  21  * thing.
  22  */
  23
  24 #include <stdlib.h>
  25 #include <stdio.h>
  26 #include <signal.h>
  27 #include <unistd.h>
  28
  29 #include <altivec.h>
  30
  31 #include "utils.h"
  32 #include "tm.h"
  33
  34 #define MAX_ATTEMPT 500000
  35
  36 #define NV_FPU_REGS 18
  37
  38 long tm_signal_self_context_load(pid_t pid, long *gprs, double *fps, vector int *vms, vector int *vss);
  39
  40 /* Be sure there are 2x as many as there are NV FPU regs (2x18) */
  41 static double fps[] = {
  42          1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
  43         -1,-2,-3,-4,-5,-6,-7,-8,-9,-10,-11,-12,-13,-14,-15,-16,-17,-18
  44 };
  45
  46 static sig_atomic_t fail;
  47
  48 static void signal_usr1(int signum, siginfo_t *info, void *uc)
  49 {
  50         int i;
  51         ucontext_t *ucp = uc;
  52         ucontext_t *tm_ucp = ucp->uc_link;
  53
  54         for (i = 0; i < NV_FPU_REGS && !fail; i++) {
  55                 fail = (ucp->uc_mcontext.fp_regs[i + 14] != fps[i]);
  56                 fail |= (tm_ucp->uc_mcontext.fp_regs[i + 14] != fps[i + NV_FPU_REGS]);
  57                 if (fail)
  58                         printf("Failed on %d FP %g or %g\n", i, ucp->uc_mcontext.fp_regs[i + 14], tm_ucp->uc_mcontext.fp_regs[i + 14]);
  59         }
  60 }
  61
  62 static int tm_signal_context_chk_fpu()
  63 {
  64         struct sigaction act;
  65         int i;
  66         long rc;
  67         pid_t pid = getpid();
  68
  69         SKIP_IF(!have_htm());
  70
  71         act.sa_sigaction = signal_usr1;
  72         sigemptyset(&act.sa_mask);
  73         act.sa_flags = SA_SIGINFO;
  74         if (sigaction(SIGUSR1, &act, NULL) < 0) {
  75                 perror("sigaction sigusr1");
  76                 exit(1);
  77         }
  78
  79         i = 0;
  80         while (i < MAX_ATTEMPT && !fail) {
  81                 rc = tm_signal_self_context_load(pid, NULL, fps, NULL, NULL);
  82                 FAIL_IF(rc != pid);
  83                 i++;
  84         }
  85
  86         return fail;
  87 }
  88
  89 int main(void)
  90 {
  91         return test_harness(tm_signal_context_chk_fpu, "tm_signal_context_chk_fpu");
  92 }