1/*
2 * Copyright (c) 1999, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25#ifndef OS_LINUX_VM_OS_LINUX_HPP
26#define OS_LINUX_VM_OS_LINUX_HPP
27
28// Linux_OS defines the interface to Linux operating systems
29
30// Information about the protection of the page at address '0' on this os.
31static bool zero_page_read_protected() { return true; }
32
33class Linux {
34  friend class os;
35  friend class TestReserveMemorySpecial;
36
37  static bool libjsig_is_loaded;        // libjsig that interposes sigaction(),
38                                        // __sigaction(), signal() is loaded
39  static struct sigaction *(*get_signal_action)(int);
40  static struct sigaction *get_preinstalled_handler(int);
41  static void save_preinstalled_handler(int, struct sigaction&);
42
43  static void check_signal_handler(int sig);
44
45  static int (*_clock_gettime)(clockid_t, struct timespec *);
46  static int (*_pthread_getcpuclockid)(pthread_t, clockid_t *);
47  static int (*_pthread_setname_np)(pthread_t, const char*);
48
49  static address   _initial_thread_stack_bottom;
50  static uintptr_t _initial_thread_stack_size;
51
52  static const char *_glibc_version;
53  static const char *_libpthread_version;
54
55  static bool _supports_fast_thread_cpu_time;
56
57  static GrowableArray<int>* _cpu_to_node;
58
59  // 0x00000000 = uninitialized,
60  // 0x01000000 = kernel version unknown,
61  // otherwise a 32-bit number:
62  // Ox00AABBCC
63  // AA, Major Version
64  // BB, Minor Version
65  // CC, Fix   Version
66  static uint32_t _os_version;
67
68 protected:
69
70  static julong _physical_memory;
71  static pthread_t _main_thread;
72  static Mutex* _createThread_lock;
73  static int _page_size;
74
75  static julong available_memory();
76  static julong physical_memory() { return _physical_memory; }
77  static void initialize_system_info();
78
79  static int commit_memory_impl(char* addr, size_t bytes, bool exec);
80  static int commit_memory_impl(char* addr, size_t bytes,
81                                size_t alignment_hint, bool exec);
82
83  static void set_glibc_version(const char *s)      { _glibc_version = s; }
84  static void set_libpthread_version(const char *s) { _libpthread_version = s; }
85
86  static void rebuild_cpu_to_node_map();
87  static GrowableArray<int>* cpu_to_node()    { return _cpu_to_node; }
88
89  static size_t find_large_page_size();
90  static size_t setup_large_page_size();
91
92  static bool setup_large_page_type(size_t page_size);
93  static bool transparent_huge_pages_sanity_check(bool warn, size_t pages_size);
94  static bool hugetlbfs_sanity_check(bool warn, size_t page_size);
95
96  static char* reserve_memory_special_shm(size_t bytes, size_t alignment, char* req_addr, bool exec);
97  static char* reserve_memory_special_huge_tlbfs(size_t bytes, size_t alignment, char* req_addr, bool exec);
98  static char* reserve_memory_special_huge_tlbfs_only(size_t bytes, char* req_addr, bool exec);
99  static char* reserve_memory_special_huge_tlbfs_mixed(size_t bytes, size_t alignment, char* req_addr, bool exec);
100
101  static bool release_memory_special_impl(char* base, size_t bytes);
102  static bool release_memory_special_shm(char* base, size_t bytes);
103  static bool release_memory_special_huge_tlbfs(char* base, size_t bytes);
104
105  static void print_full_memory_info(outputStream* st);
106  static void print_distro_info(outputStream* st);
107  static void print_libversion_info(outputStream* st);
108
109 public:
110  static bool _stack_is_executable;
111  static void *dlopen_helper(const char *name, char *ebuf, int ebuflen);
112  static void *dll_load_in_vmthread(const char *name, char *ebuf, int ebuflen);
113
114  static void init_thread_fpu_state();
115  static int  get_fpu_control_word();
116  static void set_fpu_control_word(int fpu_control);
117  static pthread_t main_thread(void)                                { return _main_thread; }
118  // returns kernel thread id (similar to LWP id on Solaris), which can be
119  // used to access /proc
120  static pid_t gettid();
121  static void set_createThread_lock(Mutex* lk)                      { _createThread_lock = lk; }
122  static Mutex* createThread_lock(void)                             { return _createThread_lock; }
123  static void hotspot_sigmask(Thread* thread);
124
125  static address   initial_thread_stack_bottom(void)                { return _initial_thread_stack_bottom; }
126  static uintptr_t initial_thread_stack_size(void)                  { return _initial_thread_stack_size; }
127  static bool is_initial_thread(void);
128
129  static int page_size(void)                                        { return _page_size; }
130  static void set_page_size(int val)                                { _page_size = val; }
131
132  static address   ucontext_get_pc(const ucontext_t* uc);
133  static void ucontext_set_pc(ucontext_t* uc, address pc);
134  static intptr_t* ucontext_get_sp(const ucontext_t* uc);
135  static intptr_t* ucontext_get_fp(const ucontext_t* uc);
136
137  // For Analyzer Forte AsyncGetCallTrace profiling support:
138  //
139  // This interface should be declared in os_linux_i486.hpp, but
140  // that file provides extensions to the os class and not the
141  // Linux class.
142  static ExtendedPC fetch_frame_from_ucontext(Thread* thread, const ucontext_t* uc,
143                                              intptr_t** ret_sp, intptr_t** ret_fp);
144
145  static bool get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr);
146
147  // This boolean allows users to forward their own non-matching signals
148  // to JVM_handle_linux_signal, harmlessly.
149  static bool signal_handlers_are_installed;
150
151  static int get_our_sigflags(int);
152  static void set_our_sigflags(int, int);
153  static void signal_sets_init();
154  static void install_signal_handlers();
155  static void set_signal_handler(int, bool);
156  static bool is_sig_ignored(int sig);
157
158  static sigset_t* unblocked_signals();
159  static sigset_t* vm_signals();
160  static sigset_t* allowdebug_blocked_signals();
161
162  // For signal-chaining
163  static struct sigaction *get_chained_signal_action(int sig);
164  static bool chained_handler(int sig, siginfo_t* siginfo, void* context);
165
166  // GNU libc and libpthread version strings
167  static const char *glibc_version()          { return _glibc_version; }
168  static const char *libpthread_version()     { return _libpthread_version; }
169
170  static void libpthread_init();
171  static bool libnuma_init();
172  static void* libnuma_dlsym(void* handle, const char* name);
173
174  // Return default guard size for the specified thread type
175  static size_t default_guard_size(os::ThreadType thr_type);
176
177  static void capture_initial_stack(size_t max_size);
178
179  // Stack overflow handling
180  static bool manually_expand_stack(JavaThread * t, address addr);
181  static int max_register_window_saves_before_flushing();
182
183  // Real-time clock functions
184  static void clock_init(void);
185
186  // fast POSIX clocks support
187  static void fast_thread_clock_init(void);
188
189  static int clock_gettime(clockid_t clock_id, struct timespec *tp) {
190    return _clock_gettime ? _clock_gettime(clock_id, tp) : -1;
191  }
192
193  static int pthread_getcpuclockid(pthread_t tid, clockid_t *clock_id) {
194    return _pthread_getcpuclockid ? _pthread_getcpuclockid(tid, clock_id) : -1;
195  }
196
197  static bool supports_fast_thread_cpu_time() {
198    return _supports_fast_thread_cpu_time;
199  }
200
201  static jlong fast_thread_cpu_time(clockid_t clockid);
202
203  static void initialize_os_info();
204  static bool os_version_is_known();
205  static uint32_t os_version();
206
207  // pthread_cond clock suppport
208 private:
209  static pthread_condattr_t _condattr[1];
210
211 public:
212  static pthread_condattr_t* condAttr() { return _condattr; }
213
214  // Stack repair handling
215
216  // none present
217
218 private:
219  typedef int (*sched_getcpu_func_t)(void);
220  typedef int (*numa_node_to_cpus_func_t)(int node, unsigned long *buffer, int bufferlen);
221  typedef int (*numa_max_node_func_t)(void);
222  typedef int (*numa_available_func_t)(void);
223  typedef int (*numa_tonode_memory_func_t)(void *start, size_t size, int node);
224  typedef void (*numa_interleave_memory_func_t)(void *start, size_t size, unsigned long *nodemask);
225  typedef void (*numa_set_bind_policy_func_t)(int policy);
226
227  static sched_getcpu_func_t _sched_getcpu;
228  static numa_node_to_cpus_func_t _numa_node_to_cpus;
229  static numa_max_node_func_t _numa_max_node;
230  static numa_available_func_t _numa_available;
231  static numa_tonode_memory_func_t _numa_tonode_memory;
232  static numa_interleave_memory_func_t _numa_interleave_memory;
233  static numa_set_bind_policy_func_t _numa_set_bind_policy;
234  static unsigned long* _numa_all_nodes;
235
236  static void set_sched_getcpu(sched_getcpu_func_t func) { _sched_getcpu = func; }
237  static void set_numa_node_to_cpus(numa_node_to_cpus_func_t func) { _numa_node_to_cpus = func; }
238  static void set_numa_max_node(numa_max_node_func_t func) { _numa_max_node = func; }
239  static void set_numa_available(numa_available_func_t func) { _numa_available = func; }
240  static void set_numa_tonode_memory(numa_tonode_memory_func_t func) { _numa_tonode_memory = func; }
241  static void set_numa_interleave_memory(numa_interleave_memory_func_t func) { _numa_interleave_memory = func; }
242  static void set_numa_set_bind_policy(numa_set_bind_policy_func_t func) { _numa_set_bind_policy = func; }
243  static void set_numa_all_nodes(unsigned long* ptr) { _numa_all_nodes = ptr; }
244  static int sched_getcpu_syscall(void);
245 public:
246  static int sched_getcpu()  { return _sched_getcpu != NULL ? _sched_getcpu() : -1; }
247  static int numa_node_to_cpus(int node, unsigned long *buffer, int bufferlen) {
248    return _numa_node_to_cpus != NULL ? _numa_node_to_cpus(node, buffer, bufferlen) : -1;
249  }
250  static int numa_max_node() { return _numa_max_node != NULL ? _numa_max_node() : -1; }
251  static int numa_available() { return _numa_available != NULL ? _numa_available() : -1; }
252  static int numa_tonode_memory(void *start, size_t size, int node) {
253    return _numa_tonode_memory != NULL ? _numa_tonode_memory(start, size, node) : -1;
254  }
255  static void numa_interleave_memory(void *start, size_t size) {
256    if (_numa_interleave_memory != NULL && _numa_all_nodes != NULL) {
257      _numa_interleave_memory(start, size, _numa_all_nodes);
258    }
259  }
260  static void numa_set_bind_policy(int policy) {
261    if (_numa_set_bind_policy != NULL) {
262      _numa_set_bind_policy(policy);
263    }
264  }
265  static int get_node_by_cpu(int cpu_id);
266};
267
268
269class PlatformEvent : public CHeapObj<mtInternal> {
270 private:
271  double CachePad[4];   // increase odds that _mutex is sole occupant of cache line
272  volatile int _Event;
273  volatile int _nParked;
274  pthread_mutex_t _mutex[1];
275  pthread_cond_t  _cond[1];
276  double PostPad[2];
277  Thread * _Assoc;
278
279 public:       // TODO-FIXME: make dtor private
280  ~PlatformEvent() { guarantee(0, "invariant"); }
281
282 public:
283  PlatformEvent() {
284    int status;
285    status = pthread_cond_init(_cond, os::Linux::condAttr());
286    assert_status(status == 0, status, "cond_init");
287    status = pthread_mutex_init(_mutex, NULL);
288    assert_status(status == 0, status, "mutex_init");
289    _Event   = 0;
290    _nParked = 0;
291    _Assoc   = NULL;
292  }
293
294  // Use caution with reset() and fired() -- they may require MEMBARs
295  void reset() { _Event = 0; }
296  int  fired() { return _Event; }
297  void park();
298  void unpark();
299  int  park(jlong millis); // relative timed-wait only
300  void SetAssociation(Thread * a) { _Assoc = a; }
301};
302
303class PlatformParker : public CHeapObj<mtInternal> {
304 protected:
305  enum {
306    REL_INDEX = 0,
307    ABS_INDEX = 1
308  };
309  int _cur_index;  // which cond is in use: -1, 0, 1
310  pthread_mutex_t _mutex[1];
311  pthread_cond_t  _cond[2]; // one for relative times and one for abs.
312
313 public:       // TODO-FIXME: make dtor private
314  ~PlatformParker() { guarantee(0, "invariant"); }
315
316 public:
317  PlatformParker() {
318    int status;
319    status = pthread_cond_init(&_cond[REL_INDEX], os::Linux::condAttr());
320    assert_status(status == 0, status, "cond_init rel");
321    status = pthread_cond_init(&_cond[ABS_INDEX], NULL);
322    assert_status(status == 0, status, "cond_init abs");
323    status = pthread_mutex_init(_mutex, NULL);
324    assert_status(status == 0, status, "mutex_init");
325    _cur_index = -1; // mark as unused
326  }
327};
328
329#endif // OS_LINUX_VM_OS_LINUX_HPP
330