LXR linux/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
  38long 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) */
  41static 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
  46static sig_atomic_t fail;
  47
  48static 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
  62static 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
  89int main(void)
  90{
  91        return test_harness(tm_signal_context_chk_fpu, "tm_signal_context_chk_fpu");
  92}
  93