1 /*
2 * Copyright (c) 1999, 2015, 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.
31 static bool zero_page_read_protected() { return true; }
32
33 class 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 static const int _vm_default_page_size;
75
76 static julong available_memory();
77 static julong physical_memory() { return _physical_memory; }
78 static void initialize_system_info();
79
80 static int commit_memory_impl(char* addr, size_t bytes, bool exec);
81 static int commit_memory_impl(char* addr, size_t bytes,
82 size_t alignment_hint, bool exec);
83
84 static void set_glibc_version(const char *s) { _glibc_version = s; }
85 static void set_libpthread_version(const char *s) { _libpthread_version = s; }
86
87 static void rebuild_cpu_to_node_map();
88 static GrowableArray<int>* cpu_to_node() { return _cpu_to_node; }
89
90 static size_t find_large_page_size();
91 static size_t setup_large_page_size();
92
93 static bool setup_large_page_type(size_t page_size);
94 static bool transparent_huge_pages_sanity_check(bool warn, size_t pages_size);
95 static bool hugetlbfs_sanity_check(bool warn, size_t page_size);
96
97 static char* reserve_memory_special_shm(size_t bytes, size_t alignment, char* req_addr, bool exec);
98 static char* reserve_memory_special_huge_tlbfs(size_t bytes, size_t alignment, char* req_addr, bool exec);
99 static char* reserve_memory_special_huge_tlbfs_only(size_t bytes, char* req_addr, bool exec);
100 static char* reserve_memory_special_huge_tlbfs_mixed(size_t bytes, size_t alignment, char* req_addr, bool exec);
101
102 static char* reserve_memory_with_backing_file(size_t bytes, char* requested_addr,
103 size_t alignment_hint, const char* backingFileDir);
104
105 static bool release_memory_special_impl(char* base, size_t bytes);
106 static bool release_memory_special_shm(char* base, size_t bytes);
107 static bool release_memory_special_huge_tlbfs(char* base, size_t bytes);
108
109 static void print_full_memory_info(outputStream* st);
110 static void print_distro_info(outputStream* st);
111 static void print_libversion_info(outputStream* st);
112
113 public:
114 static bool _stack_is_executable;
115 static void *dlopen_helper(const char *name, char *ebuf, int ebuflen);
116 static void *dll_load_in_vmthread(const char *name, char *ebuf, int ebuflen);
117
118 static void init_thread_fpu_state();
119 static int get_fpu_control_word();
120 static void set_fpu_control_word(int fpu_control);
121 static pthread_t main_thread(void) { return _main_thread; }
122 // returns kernel thread id (similar to LWP id on Solaris), which can be
123 // used to access /proc
124 static pid_t gettid();
125 static void set_createThread_lock(Mutex* lk) { _createThread_lock = lk; }
126 static Mutex* createThread_lock(void) { return _createThread_lock; }
127 static void hotspot_sigmask(Thread* thread);
128
129 static address initial_thread_stack_bottom(void) { return _initial_thread_stack_bottom; }
130 static uintptr_t initial_thread_stack_size(void) { return _initial_thread_stack_size; }
131 static bool is_initial_thread(void);
132
133 static int page_size(void) { return _page_size; }
134 static void set_page_size(int val) { _page_size = val; }
135
136 static int vm_default_page_size(void) { return _vm_default_page_size; }
137
138 static address ucontext_get_pc(const ucontext_t* uc);
139 static void ucontext_set_pc(ucontext_t* uc, address pc);
140 static intptr_t* ucontext_get_sp(const ucontext_t* uc);
141 static intptr_t* ucontext_get_fp(const ucontext_t* uc);
142
143 // For Analyzer Forte AsyncGetCallTrace profiling support:
144 //
145 // This interface should be declared in os_linux_i486.hpp, but
146 // that file provides extensions to the os class and not the
147 // Linux class.
148 static ExtendedPC fetch_frame_from_ucontext(Thread* thread, const ucontext_t* uc,
149 intptr_t** ret_sp, intptr_t** ret_fp);
150
151 static bool get_frame_at_stack_banging_point(JavaThread* thread, ucontext_t* uc, frame* fr);
152
153 // This boolean allows users to forward their own non-matching signals
154 // to JVM_handle_linux_signal, harmlessly.
155 static bool signal_handlers_are_installed;
156
157 static int get_our_sigflags(int);
158 static void set_our_sigflags(int, int);
159 static void signal_sets_init();
160 static void install_signal_handlers();
161 static void set_signal_handler(int, bool);
162 static bool is_sig_ignored(int sig);
163
164 static sigset_t* unblocked_signals();
165 static sigset_t* vm_signals();
166 static sigset_t* allowdebug_blocked_signals();
167
168 // For signal-chaining
169 static struct sigaction *get_chained_signal_action(int sig);
170 static bool chained_handler(int sig, siginfo_t* siginfo, void* context);
171
172 // GNU libc and libpthread version strings
173 static const char *glibc_version() { return _glibc_version; }
174 static const char *libpthread_version() { return _libpthread_version; }
175
176 static void libpthread_init();
177 static bool libnuma_init();
178 static void* libnuma_dlsym(void* handle, const char* name);
179 // Minimum stack size a thread can be created with (allowing
180 // the VM to completely create the thread and enter user code)
181 static size_t min_stack_allowed;
182
183 // Return default stack size or guard size for the specified thread type
184 static size_t default_stack_size(os::ThreadType thr_type);
185 static size_t default_guard_size(os::ThreadType thr_type);
186
187 static void capture_initial_stack(size_t max_size);
188
189 // Stack overflow handling
190 static bool manually_expand_stack(JavaThread * t, address addr);
191 static int max_register_window_saves_before_flushing();
192
193 // Real-time clock functions
194 static void clock_init(void);
195
196 // fast POSIX clocks support
197 static void fast_thread_clock_init(void);
198
199 static int clock_gettime(clockid_t clock_id, struct timespec *tp) {
200 return _clock_gettime ? _clock_gettime(clock_id, tp) : -1;
201 }
202
203 static int pthread_getcpuclockid(pthread_t tid, clockid_t *clock_id) {
204 return _pthread_getcpuclockid ? _pthread_getcpuclockid(tid, clock_id) : -1;
205 }
206
207 static bool supports_fast_thread_cpu_time() {
208 return _supports_fast_thread_cpu_time;
209 }
210
211 static jlong fast_thread_cpu_time(clockid_t clockid);
212
213 static void initialize_os_info();
214 static bool os_version_is_known();
215 static uint32_t os_version();
216
217 // pthread_cond clock suppport
218 private:
219 static pthread_condattr_t _condattr[1];
220
221 public:
222 static pthread_condattr_t* condAttr() { return _condattr; }
223
224 // Stack repair handling
225
226 // none present
227
228 private:
229 typedef int (*sched_getcpu_func_t)(void);
230 typedef int (*numa_node_to_cpus_func_t)(int node, unsigned long *buffer, int bufferlen);
231 typedef int (*numa_max_node_func_t)(void);
232 typedef int (*numa_available_func_t)(void);
233 typedef int (*numa_tonode_memory_func_t)(void *start, size_t size, int node);
234 typedef void (*numa_interleave_memory_func_t)(void *start, size_t size, unsigned long *nodemask);
235 typedef void (*numa_set_bind_policy_func_t)(int policy);
236
237 static sched_getcpu_func_t _sched_getcpu;
238 static numa_node_to_cpus_func_t _numa_node_to_cpus;
239 static numa_max_node_func_t _numa_max_node;
240 static numa_available_func_t _numa_available;
241 static numa_tonode_memory_func_t _numa_tonode_memory;
242 static numa_interleave_memory_func_t _numa_interleave_memory;
243 static numa_set_bind_policy_func_t _numa_set_bind_policy;
244 static unsigned long* _numa_all_nodes;
245
246 static void set_sched_getcpu(sched_getcpu_func_t func) { _sched_getcpu = func; }
247 static void set_numa_node_to_cpus(numa_node_to_cpus_func_t func) { _numa_node_to_cpus = func; }
248 static void set_numa_max_node(numa_max_node_func_t func) { _numa_max_node = func; }
249 static void set_numa_available(numa_available_func_t func) { _numa_available = func; }
250 static void set_numa_tonode_memory(numa_tonode_memory_func_t func) { _numa_tonode_memory = func; }
251 static void set_numa_interleave_memory(numa_interleave_memory_func_t func) { _numa_interleave_memory = func; }
252 static void set_numa_set_bind_policy(numa_set_bind_policy_func_t func) { _numa_set_bind_policy = func; }
253 static void set_numa_all_nodes(unsigned long* ptr) { _numa_all_nodes = ptr; }
254 static int sched_getcpu_syscall(void);
255
256 static int create_tmpfile(const char* dir, size_t size, bool exec);
257 static char* reserve_memory_with_backing_file_aligned(size_t size, size_t alignment, int fd);
258 static char* reserve_memory_with_backing_file_at(size_t bytes, char* requested_addr, int fd);
259
260
261 public:
262 static int sched_getcpu() { return _sched_getcpu != NULL ? _sched_getcpu() : -1; }
263 static int numa_node_to_cpus(int node, unsigned long *buffer, int bufferlen) {
264 return _numa_node_to_cpus != NULL ? _numa_node_to_cpus(node, buffer, bufferlen) : -1;
265 }
266 static int numa_max_node() { return _numa_max_node != NULL ? _numa_max_node() : -1; }
267 static int numa_available() { return _numa_available != NULL ? _numa_available() : -1; }
268 static int numa_tonode_memory(void *start, size_t size, int node) {
269 return _numa_tonode_memory != NULL ? _numa_tonode_memory(start, size, node) : -1;
270 }
271 static void numa_interleave_memory(void *start, size_t size) {
272 if (_numa_interleave_memory != NULL && _numa_all_nodes != NULL) {
273 _numa_interleave_memory(start, size, _numa_all_nodes);
274 }
275 }
276 static void numa_set_bind_policy(int policy) {
277 if (_numa_set_bind_policy != NULL) {
278 _numa_set_bind_policy(policy);
279 }
280 }
281 static int get_node_by_cpu(int cpu_id);
282 };
283
284
285 class PlatformEvent : public CHeapObj<mtInternal> {
286 private:
287 double CachePad[4]; // increase odds that _mutex is sole occupant of cache line
288 volatile int _Event;
289 volatile int _nParked;
290 pthread_mutex_t _mutex[1];
291 pthread_cond_t _cond[1];
292 double PostPad[2];
293 Thread * _Assoc;
294
295 public: // TODO-FIXME: make dtor private
296 ~PlatformEvent() { guarantee(0, "invariant"); }
297
298 public:
299 PlatformEvent() {
300 int status;
301 status = pthread_cond_init(_cond, os::Linux::condAttr());
302 assert_status(status == 0, status, "cond_init");
303 status = pthread_mutex_init(_mutex, NULL);
304 assert_status(status == 0, status, "mutex_init");
305 _Event = 0;
306 _nParked = 0;
307 _Assoc = NULL;
308 }
309
310 // Use caution with reset() and fired() -- they may require MEMBARs
311 void reset() { _Event = 0; }
312 int fired() { return _Event; }
313 void park();
314 void unpark();
315 int park(jlong millis); // relative timed-wait only
316 void SetAssociation(Thread * a) { _Assoc = a; }
317 };
318
319 class PlatformParker : public CHeapObj<mtInternal> {
320 protected:
321 enum {
322 REL_INDEX = 0,
323 ABS_INDEX = 1
324 };
325 int _cur_index; // which cond is in use: -1, 0, 1
326 pthread_mutex_t _mutex[1];
327 pthread_cond_t _cond[2]; // one for relative times and one for abs.
328
329 public: // TODO-FIXME: make dtor private
330 ~PlatformParker() { guarantee(0, "invariant"); }
331
332 public:
333 PlatformParker() {
334 int status;
335 status = pthread_cond_init(&_cond[REL_INDEX], os::Linux::condAttr());
336 assert_status(status == 0, status, "cond_init rel");
337 status = pthread_cond_init(&_cond[ABS_INDEX], NULL);
338 assert_status(status == 0, status, "cond_init abs");
339 status = pthread_mutex_init(_mutex, NULL);
340 assert_status(status == 0, status, "mutex_init");
341 _cur_index = -1; // mark as unused
342 }
343 };
344
345 #endif // OS_LINUX_VM_OS_LINUX_HPP