tools/testing/selftests/powerpc/ptrace/ptrace-tm-spr.c

   1 /*
   2  * Ptrace test TM SPR registers
   3  *
   4  * Copyright (C) 2015 Anshuman Khandual, IBM Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11 #include "ptrace.h"
  12 #include "tm.h"
  13
  14 /* Tracee and tracer shared data */
  15 struct shared {
  16         int flag;
  17         struct tm_spr_regs regs;
  18 };
  19 unsigned long tfhar;
  20
  21 int shm_id;
  22 struct shared *cptr, *pptr;
  23
  24 int shm_id1;
  25 int *cptr1, *pptr1;
  26
  27 #define TM_KVM_SCHED   0xe0000001ac000001
  28 int validate_tm_spr(struct tm_spr_regs *regs)
  29 {
  30         FAIL_IF(regs->tm_tfhar != tfhar);
  31         FAIL_IF((regs->tm_texasr == TM_KVM_SCHED) && (regs->tm_tfiar != 0));
  32
  33         return TEST_PASS;
  34 }
  35
  36 void tm_spr(void)
  37 {
  38         unsigned long result, texasr;
  39         int ret;
  40
  41         cptr = (struct shared *)shmat(shm_id, NULL, 0);
  42         cptr1 = (int *)shmat(shm_id1, NULL, 0);
  43
  44 trans:
  45         cptr1[0] = 0;
  46         asm __volatile__(
  47                 "1: ;"
  48                 /* TM failover handler should follow "tbegin.;" */
  49                 "mflr 31;"
  50                 "bl 4f;"        /* $ = TFHAR - 12 */
  51                 "4: ;"
  52                 "mflr %[tfhar];"
  53                 "mtlr 31;"
  54
  55                 "tbegin.;"
  56                 "beq 2f;"
  57
  58                 "tsuspend.;"
  59                 "li 8, 1;"
  60                 "sth 8, 0(%[cptr1]);"
  61                 "tresume.;"
  62                 "b .;"
  63
  64                 "tend.;"
  65                 "li 0, 0;"
  66                 "ori %[res], 0, 0;"
  67                 "b 3f;"
  68
  69                 "2: ;"
  70
  71                 "li 0, 1;"
  72                 "ori %[res], 0, 0;"
  73                 "mfspr %[texasr], %[sprn_texasr];"
  74
  75                 "3: ;"
  76                 : [tfhar] "=r" (tfhar), [res] "=r" (result),
  77                 [texasr] "=r" (texasr), [cptr1] "=r" (cptr1)
  78                 : [sprn_texasr] "i"  (SPRN_TEXASR)
  79                 : "memory", "r0", "r8", "r31"
  80                 );
  81
  82         /* There are 2 32bit instructions before tbegin. */
  83         tfhar += 12;
  84
  85         if (result) {
  86                 if (!cptr->flag)
  87                         goto trans;
  88
  89                 ret = validate_tm_spr((struct tm_spr_regs *)&cptr->regs);
  90                 shmdt((void *)cptr);
  91                 shmdt((void *)cptr1);
  92                 if (ret)
  93                         exit(1);
  94                 exit(0);
  95         }
  96         shmdt((void *)cptr);
  97         shmdt((void *)cptr1);
  98         exit(1);
  99 }
 100
 101 int trace_tm_spr(pid_t child)
 102 {
 103         FAIL_IF(start_trace(child));
 104         FAIL_IF(show_tm_spr(child, (struct tm_spr_regs *)&pptr->regs));
 105
 106         printf("TFHAR: %lx TEXASR: %lx TFIAR: %lx\n", pptr->regs.tm_tfhar,
 107                                 pptr->regs.tm_texasr, pptr->regs.tm_tfiar);
 108
 109         pptr->flag = 1;
 110         FAIL_IF(stop_trace(child));
 111
 112         return TEST_PASS;
 113 }
 114
 115 int ptrace_tm_spr(void)
 116 {
 117         pid_t pid;
 118         int ret, status;
 119
 120         SKIP_IF(!have_htm());
 121         shm_id = shmget(IPC_PRIVATE, sizeof(struct shared), 0777|IPC_CREAT);
 122         shm_id1 = shmget(IPC_PRIVATE, sizeof(int), 0777|IPC_CREAT);
 123         pid = fork();
 124         if (pid < 0) {
 125                 perror("fork() failed");
 126                 return TEST_FAIL;
 127         }
 128
 129         if (pid == 0)
 130                 tm_spr();
 131
 132         if (pid) {
 133                 pptr = (struct shared *)shmat(shm_id, NULL, 0);
 134                 pptr1 = (int *)shmat(shm_id1, NULL, 0);
 135
 136                 while (!pptr1[0])
 137                         asm volatile("" : : : "memory");
 138                 ret = trace_tm_spr(pid);
 139                 if (ret) {
 140                         kill(pid, SIGKILL);
 141                         shmdt((void *)pptr);
 142                         shmdt((void *)pptr1);
 143                         shmctl(shm_id, IPC_RMID, NULL);
 144                         shmctl(shm_id1, IPC_RMID, NULL);
 145                         return TEST_FAIL;
 146                 }
 147
 148                 shmdt((void *)pptr);
 149                 shmdt((void *)pptr1);
 150                 ret = wait(&status);
 151                 shmctl(shm_id, IPC_RMID, NULL);
 152                 shmctl(shm_id1, IPC_RMID, NULL);
 153                 if (ret != pid) {
 154                         printf("Child's exit status not captured\n");
 155                         return TEST_FAIL;
 156                 }
 157
 158                 return (WIFEXITED(status) && WEXITSTATUS(status)) ? TEST_FAIL :
 159                         TEST_PASS;
 160         }
 161         return TEST_PASS;
 162 }
 163
 164 int main(int argc, char *argv[])
 165 {
 166         return test_harness(ptrace_tm_spr, "ptrace_tm_spr");
 167 }