LXR linux/tools/testing/selftests/powerpc/tm/tm-signal-context-chk-vsx.c

   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.
   9 * Expected behaviour is that the checkpointed state is in the user
  10 * context passed to the signal handler. The speculated state can be
  11 * accessed with the uc_link pointer.
  12 *
  13 * The rationale for this is that if TM unaware code (which linked
  14 * against TM libs) installs a signal handler it will not know of the
  15 * speculative nature of the 'live' registers and may infer the wrong
  16 * thing.
  17 */
  18
  19#include <stdlib.h>
  20#include <stdio.h>
  21#include <string.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_VSX_REGS 12
  33
  34long tm_signal_self_context_load(pid_t pid, long *gprs, double *fps, vector int *vms, vector int *vss);
  35
  36static sig_atomic_t fail;
  37
  38vector int vss[] = {
  39        {1, 2, 3, 4 },{5, 6, 7, 8 },{9, 10,11,12},
  40        {13,14,15,16},{17,18,19,20},{21,22,23,24},
  41        {25,26,27,28},{29,30,31,32},{33,34,35,36},
  42        {37,38,39,40},{41,42,43,44},{45,46,47,48},
  43        {-1, -2, -3, -4 },{-5, -6, -7, -8 },{-9, -10,-11,-12},
  44        {-13,-14,-15,-16},{-17,-18,-19,-20},{-21,-22,-23,-24},
  45        {-25,-26,-27,-28},{-29,-30,-31,-32},{-33,-34,-35,-36},
  46        {-37,-38,-39,-40},{-41,-42,-43,-44},{-45,-46,-47,-48}
  47};
  48
  49static void signal_usr1(int signum, siginfo_t *info, void *uc)
  50{
  51        int i;
  52        uint8_t vsc[sizeof(vector int)];
  53        uint8_t vst[sizeof(vector int)];
  54        ucontext_t *ucp = uc;
  55        ucontext_t *tm_ucp = ucp->uc_link;
  56
  57        /*
  58         * The other half of the VSX regs will be after v_regs.
  59         *
  60         * In short, vmx_reserve array holds everything. v_regs is a 16
  61         * byte aligned pointer at the start of vmx_reserve (vmx_reserve
  62         * may or may not be 16 aligned) where the v_regs structure exists.
  63         * (half of) The VSX regsters are directly after v_regs so the
  64         * easiest way to find them below.
  65         */
  66        long *vsx_ptr = (long *)(ucp->uc_mcontext.v_regs + 1);
  67        long *tm_vsx_ptr = (long *)(tm_ucp->uc_mcontext.v_regs + 1);
  68        for (i = 0; i < NV_VSX_REGS && !fail; i++) {
  69                memcpy(vsc, &ucp->uc_mcontext.fp_regs[i + 20], 8);
  70                memcpy(vsc + 8, &vsx_ptr[20 + i], 8);
  71                fail = memcmp(vsc, &vss[i], sizeof(vector int));
  72                memcpy(vst, &tm_ucp->uc_mcontext.fp_regs[i + 20], 8);
  73                memcpy(vst + 8, &tm_vsx_ptr[20 + i], 8);
  74                fail |= memcmp(vst, &vss[i + NV_VSX_REGS], sizeof(vector int));
  75
  76                if (fail) {
  77                        int j;
  78
  79                        fprintf(stderr, "Failed on %d vsx 0x", i);
  80                        for (j = 0; j < 16; j++)
  81                                fprintf(stderr, "%02x", vsc[j]);
  82                        fprintf(stderr, " vs 0x");
  83                        for (j = 0; j < 16; j++)
  84                                fprintf(stderr, "%02x", vst[j]);
  85                        fprintf(stderr, "\n");
  86                }
  87        }
  88}
  89
  90static int tm_signal_context_chk()
  91{
  92        struct sigaction act;
  93        int i;
  94        long rc;
  95        pid_t pid = getpid();
  96
  97        SKIP_IF(!have_htm());
  98
  99        act.sa_sigaction = signal_usr1;
 100        sigemptyset(&act.sa_mask);
 101        act.sa_flags = SA_SIGINFO;
 102        if (sigaction(SIGUSR1, &act, NULL) < 0) {
 103                perror("sigaction sigusr1");
 104                exit(1);
 105        }
 106
 107        i = 0;
 108        while (i < MAX_ATTEMPT && !fail) {
 109                rc = tm_signal_self_context_load(pid, NULL, NULL, NULL, vss);
 110                FAIL_IF(rc != pid);
 111                i++;
 112        }
 113
 114        return fail;
 115}
 116
 117int main(void)
 118{
 119        return test_harness(tm_signal_context_chk, "tm_signal_context_chk_vsx");
 120}
 121