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
  34 long tm_signal_self_context_load(pid_t pid, long *gprs, double *fps, vector int *vms, vector int *vss);
  35
  36 static sig_atomic_t fail;
  37
  38 vector 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
  49 static 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
  90 static 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
 117 int main(void)
 118 {
 119         return test_harness(tm_signal_context_chk, "tm_signal_context_chk_vsx");
 120 }