Revert "Add a test exercising ptrace watchpoint functionality"

This test appears to be failing on shamu devices. Revert until we figure out what's the problem.

This reverts commit 88ce78d93a465c1c635901d26542d5ec07b6b6ee.

Bug: 28514348
Change-Id: I0d91ca5eb59eb3ccb5d48b02b245e0f1bcffb5bb
diff --git a/tests/Android.mk b/tests/Android.mk
index 0d57f29..956b76f 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -98,7 +98,6 @@
     sys_personality_test.cpp \
     sys_prctl_test.cpp \
     sys_procfs_test.cpp \
-    sys_ptrace_test.cpp \
     sys_resource_test.cpp \
     sys_select_test.cpp \
     sys_sendfile_test.cpp \
diff --git a/tests/sys_ptrace_test.cpp b/tests/sys_ptrace_test.cpp
deleted file mode 100644
index bd84d30..0000000
--- a/tests/sys_ptrace_test.cpp
+++ /dev/null
@@ -1,202 +0,0 @@
-/*
- * Copyright (C) 2016 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include <sys/ptrace.h>
-
-#include <elf.h>
-#include <sched.h>
-#include <sys/prctl.h>
-#include <sys/uio.h>
-#include <sys/user.h>
-#include <unistd.h>
-
-#include <gtest/gtest.h>
-
-// Host libc does not define this.
-#ifndef TRAP_HWBKPT
-#define TRAP_HWBKPT 4
-#endif
-
-template<typename T>
-static void __attribute__((noreturn)) fork_child(unsigned cpu, T &data) {
-  // Extra precaution: make sure we go away if anything happens to our parent.
-  if (prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0) == -1) {
-    perror("prctl(PR_SET_PDEATHSIG)");
-    _exit(1);
-  }
-
-  cpu_set_t cpus;
-  CPU_ZERO(&cpus);
-  CPU_SET(cpu, &cpus);
-  if (sched_setaffinity(0, sizeof cpus, &cpus) == -1) {
-    perror("sched_setaffinity");
-    _exit(2);
-  }
-  if (ptrace(PTRACE_TRACEME, 0, nullptr, nullptr) == -1) {
-    perror("ptrace(PTRACE_TRACEME)");
-    _exit(3);
-  }
-
-  raise(SIGSTOP); // Synchronize with the tracer, let it set the watchpoint.
-
-  data = 1; // Now trigger the watchpoint.
-
-  _exit(0);
-}
-
-class ChildGuard {
- public:
-  ChildGuard(pid_t pid) : pid(pid) {}
-
-  ~ChildGuard() {
-    kill(pid, SIGKILL);
-    int status;
-    waitpid(pid, &status, 0);
-  }
-
- private:
-  pid_t pid;
-};
-
-static bool are_watchpoints_supported(pid_t child) {
-#if defined(__arm__)
-  long capabilities;
-  long result = ptrace(PTRACE_GETHBPREGS, child, 0, &capabilities);
-  if (result == -1) {
-    EXPECT_EQ(EIO, errno);
-    return false;
-  }
-  return ((capabilities >> 8) & 0xff) > 0;
-#elif defined(__aarch64__)
-  user_hwdebug_state dreg_state;
-  iovec iov;
-  iov.iov_base = &dreg_state;
-  iov.iov_len = sizeof(dreg_state);
-
-  long result = ptrace(PTRACE_GETREGSET, child, NT_ARM_HW_WATCH, &iov);
-  if (result == -1) {
-    EXPECT_EQ(EINVAL, errno);
-    return false;
-  }
-  return (dreg_state.dbg_info & 0xff) > 0;
-#elif defined(__i386__) || defined(__x86_64__)
-  // We assume watchpoints are always supported on x86.
-  (void) child;
-  return true;
-#else
-  // TODO: mips support.
-  (void) child;
-  return false;
-#endif
-}
-
-static void set_watchpoint(pid_t child, const void *address, size_t size) {
-#if defined(__arm__) || defined(__aarch64__)
-  const unsigned byte_mask = (1 << size) - 1;
-  const unsigned type = 2; // Write.
-  const unsigned enable = 1;
-  const unsigned control = byte_mask << 5 | type << 3 | enable;
-
-#ifdef __arm__
-  ASSERT_EQ(0, ptrace(PTRACE_SETHBPREGS, child, -1, &address)) << strerror(errno);
-  ASSERT_EQ(0, ptrace(PTRACE_SETHBPREGS, child, -2, &control)) << strerror(errno);
-#else // aarch64
-  user_hwdebug_state dreg_state;
-  memset(&dreg_state, 0, sizeof dreg_state);
-  dreg_state.dbg_regs[0].addr = reinterpret_cast<uintptr_t>(address);
-  dreg_state.dbg_regs[0].ctrl = control;
-
-  iovec iov;
-  iov.iov_base = &dreg_state;
-  iov.iov_len = offsetof(user_hwdebug_state, dbg_regs) + sizeof(dreg_state.dbg_regs[0]);
-
-  ASSERT_EQ(0, ptrace(PTRACE_SETREGSET, child, NT_ARM_HW_WATCH, &iov)) << strerror(errno);
-#endif
-#elif defined(__i386__) || defined(__x86_64__)
-  ASSERT_EQ(0, ptrace(PTRACE_POKEUSER, child, offsetof(user, u_debugreg[0]), address)) << strerror(errno);
-  errno = 0;
-  unsigned data = ptrace(PTRACE_PEEKUSER, child, offsetof(user, u_debugreg[7]), nullptr);
-  ASSERT_EQ(0, errno);
-
-  const unsigned size_flag = (size == 8) ? 2 : size - 1;
-  const unsigned enable = 1;
-  const unsigned type = 1; // Write.
-
-  const unsigned mask = 3 << 18 | 3 << 16 | 1;
-  const unsigned value = size_flag << 18 | type << 16 | enable;
-  data &= mask;
-  data |= value;
-  ASSERT_EQ(0, ptrace(PTRACE_POKEUSER, child, offsetof(user, u_debugreg[7]), data)) << strerror(errno);
-#else
-  (void) child;
-  (void) address;
-  (void) size;
-#endif
-}
-
-template<typename T>
-static void run_watchpoint_test_impl(unsigned cpu) {
-  alignas(8) T data = 0;
-
-  pid_t child = fork();
-  ASSERT_NE(-1, child) << strerror(errno);
-  if (child == 0) fork_child(cpu, data);
-
-  ChildGuard guard(child);
-
-  int status;
-  ASSERT_EQ(child, waitpid(child, &status, __WALL)) << strerror(errno);
-  ASSERT_TRUE(WIFSTOPPED(status)) << "Status was: " << status;
-  ASSERT_EQ(SIGSTOP, WSTOPSIG(status)) << "Status was: " << status;
-
-  if (!are_watchpoints_supported(child)) return;
-
-  set_watchpoint(child, &data, sizeof data);
-
-  ASSERT_EQ(0, ptrace(PTRACE_CONT, child, nullptr, nullptr)) << strerror(errno);
-  ASSERT_EQ(child, waitpid(child, &status, __WALL)) << strerror(errno);
-  ASSERT_TRUE(WIFSTOPPED(status)) << "Status was: " << status;
-  ASSERT_EQ(SIGTRAP, WSTOPSIG(status)) << "Status was: " << status;
-
-  siginfo_t siginfo;
-  ASSERT_EQ(0, ptrace(PTRACE_GETSIGINFO, child, nullptr, &siginfo)) << strerror(errno);
-  ASSERT_EQ(TRAP_HWBKPT, siginfo.si_code);
-#if defined(__arm__) || defined(__aarch64__)
-  ASSERT_EQ(&data, siginfo.si_addr);
-#endif
-}
-
-static void run_watchpoint_test(unsigned cpu) {
-  run_watchpoint_test_impl<uint8_t>(cpu);
-  run_watchpoint_test_impl<uint16_t>(cpu);
-  run_watchpoint_test_impl<uint32_t>(cpu);
-#if __LP64__
-  run_watchpoint_test_impl<uint64_t>(cpu);
-#endif
-}
-
-// Test watchpoint API. The test is considered successful if our watchpoints get hit OR the
-// system reports that watchpoint support is not present. We run the test for different
-// watchpoint sizes, while pinning the process to each cpu in turn, for better coverage.
-TEST(ptrace, watchpoint_stress) {
-  cpu_set_t available_cpus;
-  ASSERT_EQ(0, sched_getaffinity(0, sizeof available_cpus, &available_cpus));
-
-  for (size_t cpu = 0; cpu < CPU_SETSIZE; ++cpu) {
-    if (!CPU_ISSET(cpu, &available_cpus)) continue;
-    run_watchpoint_test(cpu);
-  }
-}