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", "r1", "r2", "r3", "r4",
  80                 "r8", "r9", "r10", "r11", "r31"
  81                 );
  82
  83         /* There are 2 32bit instructions before tbegin. */
  84         tfhar += 12;
  85
  86         if (result) {
  87                 if (!cptr->flag)
  88                         goto trans;
  89
  90                 ret = validate_tm_spr((struct tm_spr_regs *)&cptr->regs);
  91                 shmdt((void *)cptr);
  92                 shmdt((void *)cptr1);
  93                 if (ret)
  94                         exit(1);
  95                 exit(0);
  96         }
  97         shmdt((void *)cptr);
  98         shmdt((void *)cptr1);
  99         exit(1);
 100 }
 101
 102 int trace_tm_spr(pid_t child)
 103 {
 104         FAIL_IF(start_trace(child));
 105         FAIL_IF(show_tm_spr(child, (struct tm_spr_regs *)&pptr->regs));
 106
 107         printf("TFHAR: %lx TEXASR: %lx TFIAR: %lx\n", pptr->regs.tm_tfhar,
 108                                 pptr->regs.tm_texasr, pptr->regs.tm_tfiar);
 109
 110         pptr->flag = 1;
 111         FAIL_IF(stop_trace(child));
 112
 113         return TEST_PASS;
 114 }
 115
 116 int ptrace_tm_spr(void)
 117 {
 118         pid_t pid;
 119         int ret, status;
 120
 121         SKIP_IF(!have_htm());
 122         shm_id = shmget(IPC_PRIVATE, sizeof(struct shared), 0777|IPC_CREAT);
 123         shm_id1 = shmget(IPC_PRIVATE, sizeof(int), 0777|IPC_CREAT);
 124         pid = fork();
 125         if (pid < 0) {
 126                 perror("fork() failed");
 127                 return TEST_FAIL;
 128         }
 129
 130         if (pid == 0)
 131                 tm_spr();
 132
 133         if (pid) {
 134                 pptr = (struct shared *)shmat(shm_id, NULL, 0);
 135                 pptr1 = (int *)shmat(shm_id1, NULL, 0);
 136
 137                 while (!pptr1[0])
 138                         asm volatile("" : : : "memory");
 139                 ret = trace_tm_spr(pid);
 140                 if (ret) {
 141                         kill(pid, SIGKILL);
 142                         shmdt((void *)pptr);
 143                         shmdt((void *)pptr1);
 144                         shmctl(shm_id, IPC_RMID, NULL);
 145                         shmctl(shm_id1, IPC_RMID, NULL);
 146                         return TEST_FAIL;
 147                 }
 148
 149                 shmdt((void *)pptr);
 150                 shmdt((void *)pptr1);
 151                 ret = wait(&status);
 152                 shmctl(shm_id, IPC_RMID, NULL);
 153                 shmctl(shm_id1, IPC_RMID, NULL);
 154                 if (ret != pid) {
 155                         printf("Child's exit status not captured\n");
 156                         return TEST_FAIL;
 157                 }
 158
 159                 return (WIFEXITED(status) && WEXITSTATUS(status)) ? TEST_FAIL :
 160                         TEST_PASS;
 161         }
 162         return TEST_PASS;
 163 }
 164
 165 int main(int argc, char *argv[])
 166 {
 167         return test_harness(ptrace_tm_spr, "ptrace_tm_spr");
 168 }