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

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Ptrace test TM SPR registers
   4 *
   5 * Copyright (C) 2015 Anshuman Khandual, IBM Corporation.
   6 */
   7#include "ptrace.h"
   8#include "tm.h"
   9
  10/* Tracee and tracer shared data */
  11struct shared {
  12        int flag;
  13        struct tm_spr_regs regs;
  14};
  15unsigned long tfhar;
  16
  17int shm_id;
  18struct shared *cptr, *pptr;
  19
  20int shm_id1;
  21int *cptr1, *pptr1;
  22
  23#define TM_KVM_SCHED   0xe0000001ac000001
  24int validate_tm_spr(struct tm_spr_regs *regs)
  25{
  26        FAIL_IF(regs->tm_tfhar != tfhar);
  27        FAIL_IF((regs->tm_texasr == TM_KVM_SCHED) && (regs->tm_tfiar != 0));
  28
  29        return TEST_PASS;
  30}
  31
  32void tm_spr(void)
  33{
  34        unsigned long result, texasr;
  35        int ret;
  36
  37        cptr = (struct shared *)shmat(shm_id, NULL, 0);
  38        cptr1 = (int *)shmat(shm_id1, NULL, 0);
  39
  40trans:
  41        cptr1[0] = 0;
  42        asm __volatile__(
  43                "1: ;"
  44                /* TM failover handler should follow "tbegin.;" */
  45                "mflr 31;"
  46                "bl 4f;"        /* $ = TFHAR - 12 */
  47                "4: ;"
  48                "mflr %[tfhar];"
  49                "mtlr 31;"
  50
  51                "tbegin.;"
  52                "beq 2f;"
  53
  54                "tsuspend.;"
  55                "li 8, 1;"
  56                "sth 8, 0(%[cptr1]);"
  57                "tresume.;"
  58                "b .;"
  59
  60                "tend.;"
  61                "li 0, 0;"
  62                "ori %[res], 0, 0;"
  63                "b 3f;"
  64
  65                "2: ;"
  66
  67                "li 0, 1;"
  68                "ori %[res], 0, 0;"
  69                "mfspr %[texasr], %[sprn_texasr];"
  70
  71                "3: ;"
  72                : [tfhar] "=r" (tfhar), [res] "=r" (result),
  73                [texasr] "=r" (texasr), [cptr1] "=b" (cptr1)
  74                : [sprn_texasr] "i"  (SPRN_TEXASR)
  75                : "memory", "r0", "r8", "r31"
  76                );
  77
  78        /* There are 2 32bit instructions before tbegin. */
  79        tfhar += 12;
  80
  81        if (result) {
  82                if (!cptr->flag)
  83                        goto trans;
  84
  85                ret = validate_tm_spr((struct tm_spr_regs *)&cptr->regs);
  86                shmdt((void *)cptr);
  87                shmdt((void *)cptr1);
  88                if (ret)
  89                        exit(1);
  90                exit(0);
  91        }
  92        shmdt((void *)cptr);
  93        shmdt((void *)cptr1);
  94        exit(1);
  95}
  96
  97int trace_tm_spr(pid_t child)
  98{
  99        FAIL_IF(start_trace(child));
 100        FAIL_IF(show_tm_spr(child, (struct tm_spr_regs *)&pptr->regs));
 101
 102        printf("TFHAR: %lx TEXASR: %lx TFIAR: %lx\n", pptr->regs.tm_tfhar,
 103                                pptr->regs.tm_texasr, pptr->regs.tm_tfiar);
 104
 105        pptr->flag = 1;
 106        FAIL_IF(stop_trace(child));
 107
 108        return TEST_PASS;
 109}
 110
 111int ptrace_tm_spr(void)
 112{
 113        pid_t pid;
 114        int ret, status;
 115
 116        SKIP_IF(!have_htm());
 117        shm_id = shmget(IPC_PRIVATE, sizeof(struct shared), 0777|IPC_CREAT);
 118        shm_id1 = shmget(IPC_PRIVATE, sizeof(int), 0777|IPC_CREAT);
 119        pid = fork();
 120        if (pid < 0) {
 121                perror("fork() failed");
 122                return TEST_FAIL;
 123        }
 124
 125        if (pid == 0)
 126                tm_spr();
 127
 128        if (pid) {
 129                pptr = (struct shared *)shmat(shm_id, NULL, 0);
 130                pptr1 = (int *)shmat(shm_id1, NULL, 0);
 131
 132                while (!pptr1[0])
 133                        asm volatile("" : : : "memory");
 134                ret = trace_tm_spr(pid);
 135                if (ret) {
 136                        kill(pid, SIGKILL);
 137                        shmdt((void *)pptr);
 138                        shmdt((void *)pptr1);
 139                        shmctl(shm_id, IPC_RMID, NULL);
 140                        shmctl(shm_id1, IPC_RMID, NULL);
 141                        return TEST_FAIL;
 142                }
 143
 144                shmdt((void *)pptr);
 145                shmdt((void *)pptr1);
 146                ret = wait(&status);
 147                shmctl(shm_id, IPC_RMID, NULL);
 148                shmctl(shm_id1, IPC_RMID, NULL);
 149                if (ret != pid) {
 150                        printf("Child's exit status not captured\n");
 151                        return TEST_FAIL;
 152                }
 153
 154                return (WIFEXITED(status) && WEXITSTATUS(status)) ? TEST_FAIL :
 155                        TEST_PASS;
 156        }
 157        return TEST_PASS;
 158}
 159
 160int main(int argc, char *argv[])
 161{
 162        return test_harness(ptrace_tm_spr, "ptrace_tm_spr");
 163}
 164