tools/testing/selftests/powerpc/tm/tm-signal-context-chk-vsx.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 <string.h>
  27 #include <signal.h>
  28 #include <unistd.h>
  29
  30 #include <altivec.h>
  31
  32 #include "utils.h"
  33 #include "tm.h"
  34
  35 #define MAX_ATTEMPT 500000
  36
  37 #define NV_VSX_REGS 12
  38
  39 long tm_signal_self_context_load(pid_t pid, long *gprs, double *fps, vector int *vms, vector int *vss);
  40
  41 static sig_atomic_t fail;
  42
  43 vector int vss[] = {
  44         {1, 2, 3, 4 },{5, 6, 7, 8 },{9, 10,11,12},
  45         {13,14,15,16},{17,18,19,20},{21,22,23,24},
  46         {25,26,27,28},{29,30,31,32},{33,34,35,36},
  47         {37,38,39,40},{41,42,43,44},{45,46,47,48},
  48         {-1, -2, -3, -4 },{-5, -6, -7, -8 },{-9, -10,-11,-12},
  49         {-13,-14,-15,-16},{-17,-18,-19,-20},{-21,-22,-23,-24},
  50         {-25,-26,-27,-28},{-29,-30,-31,-32},{-33,-34,-35,-36},
  51         {-37,-38,-39,-40},{-41,-42,-43,-44},{-45,-46,-47,-48}
  52 };
  53
  54 static void signal_usr1(int signum, siginfo_t *info, void *uc)
  55 {
  56         int i;
  57         uint8_t vsc[sizeof(vector int)];
  58         uint8_t vst[sizeof(vector int)];
  59         ucontext_t *ucp = uc;
  60         ucontext_t *tm_ucp = ucp->uc_link;
  61
  62         /*
  63          * The other half of the VSX regs will be after v_regs.
  64          *
  65          * In short, vmx_reserve array holds everything. v_regs is a 16
  66          * byte aligned pointer at the start of vmx_reserve (vmx_reserve
  67          * may or may not be 16 aligned) where the v_regs structure exists.
  68          * (half of) The VSX regsters are directly after v_regs so the
  69          * easiest way to find them below.
  70          */
  71         long *vsx_ptr = (long *)(ucp->uc_mcontext.v_regs + 1);
  72         long *tm_vsx_ptr = (long *)(tm_ucp->uc_mcontext.v_regs + 1);
  73         for (i = 0; i < NV_VSX_REGS && !fail; i++) {
  74                 memcpy(vsc, &ucp->uc_mcontext.fp_regs[i + 20], 8);
  75                 memcpy(vsc + 8, &vsx_ptr[20 + i], 8);
  76                 fail = memcmp(vsc, &vss[i], sizeof(vector int));
  77                 memcpy(vst, &tm_ucp->uc_mcontext.fp_regs[i + 20], 8);
  78                 memcpy(vst + 8, &tm_vsx_ptr[20 + i], 8);
  79                 fail |= memcmp(vst, &vss[i + NV_VSX_REGS], sizeof(vector int));
  80
  81                 if (fail) {
  82                         int j;
  83
  84                         fprintf(stderr, "Failed on %d vsx 0x", i);
  85                         for (j = 0; j < 16; j++)
  86                                 fprintf(stderr, "%02x", vsc[j]);
  87                         fprintf(stderr, " vs 0x");
  88                         for (j = 0; j < 16; j++)
  89                                 fprintf(stderr, "%02x", vst[j]);
  90                         fprintf(stderr, "\n");
  91                 }
  92         }
  93 }
  94
  95 static int tm_signal_context_chk()
  96 {
  97         struct sigaction act;
  98         int i;
  99         long rc;
 100         pid_t pid = getpid();
 101
 102         SKIP_IF(!have_htm());
 103
 104         act.sa_sigaction = signal_usr1;
 105         sigemptyset(&act.sa_mask);
 106         act.sa_flags = SA_SIGINFO;
 107         if (sigaction(SIGUSR1, &act, NULL) < 0) {
 108                 perror("sigaction sigusr1");
 109                 exit(1);
 110         }
 111
 112         i = 0;
 113         while (i < MAX_ATTEMPT && !fail) {
 114                 rc = tm_signal_self_context_load(pid, NULL, NULL, NULL, vss);
 115                 FAIL_IF(rc != pid);
 116                 i++;
 117         }
 118
 119         return fail;
 120 }
 121
 122 int main(void)
 123 {
 124         return test_harness(tm_signal_context_chk, "tm_signal_context_chk_vsx");
 125 }