1 /*
2 * Copyright (c) 1999, 2013, 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 /* pthread_getattr_np comes with LinuxThreads-0.9-7 on RedHat 7.1 */
31 typedef int (*pthread_getattr_func_type) (pthread_t, pthread_attr_t *);
32
33 class Linux {
34 friend class os;
35 friend class TestReserveMemorySpecial;
36
37 // For signal-chaining
38 #define MAXSIGNUM 32
39 static struct sigaction sigact[MAXSIGNUM]; // saved preinstalled sigactions
40 static unsigned int sigs; // mask of signals that have
41 // preinstalled signal handlers
42 static bool libjsig_is_loaded; // libjsig that interposes sigaction(),
43 // __sigaction(), signal() is loaded
44 static struct sigaction *(*get_signal_action)(int);
45 static struct sigaction *get_preinstalled_handler(int);
46 static void save_preinstalled_handler(int, struct sigaction&);
47
48 static void check_signal_handler(int sig);
49
50 // For signal flags diagnostics
51 static int sigflags[MAXSIGNUM];
52
53 static int (*_clock_gettime)(clockid_t, struct timespec *);
54 static int (*_pthread_getcpuclockid)(pthread_t, clockid_t *);
55
56 static address _initial_thread_stack_bottom;
57 static uintptr_t _initial_thread_stack_size;
58
59 static const char *_glibc_version;
60 static const char *_libpthread_version;
61
62 static bool _is_floating_stack;
63 static bool _is_NPTL;
64 static bool _supports_fast_thread_cpu_time;
65
66 static GrowableArray<int>* _cpu_to_node;
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 bool supports_variable_stack_size();
88
89 static void set_is_NPTL() { _is_NPTL = true; }
90 static void set_is_LinuxThreads() { _is_NPTL = false; }
91 static void set_is_floating_stack() { _is_floating_stack = true; }
92
93 static void rebuild_cpu_to_node_map();
94 static GrowableArray<int>* cpu_to_node() { return _cpu_to_node; }
95
96 static size_t find_large_page_size();
97 static size_t setup_large_page_size();
98
99 static bool setup_large_page_type(size_t page_size);
100 static bool transparent_huge_pages_sanity_check(bool warn, size_t pages_size);
101 static bool hugetlbfs_sanity_check(bool warn, size_t page_size);
102
103 static char* reserve_memory_special_shm(size_t bytes, size_t alignment, char* req_addr, bool exec);
104 static char* reserve_memory_special_huge_tlbfs(size_t bytes, size_t alignment, char* req_addr, bool exec);
105 static char* reserve_memory_special_huge_tlbfs_only(size_t bytes, char* req_addr, bool exec);
106 static char* reserve_memory_special_huge_tlbfs_mixed(size_t bytes, size_t alignment, char* req_addr, bool exec);
107
108 static bool release_memory_special_shm(char* base, size_t bytes);
109 static bool release_memory_special_huge_tlbfs(char* base, size_t bytes);
110
111 static void print_full_memory_info(outputStream* st);
112 static void print_distro_info(outputStream* st);
113 static void print_libversion_info(outputStream* st);
114
115 public:
116 static bool _stack_is_executable;
117 static void *dlopen_helper(const char *name, char *ebuf, int ebuflen);
118 static void *dll_load_in_vmthread(const char *name, char *ebuf, int ebuflen);
119
120 static void init_thread_fpu_state();
121 static int get_fpu_control_word();
122 static void set_fpu_control_word(int fpu_control);
123 static pthread_t main_thread(void) { return _main_thread; }
124 // returns kernel thread id (similar to LWP id on Solaris), which can be
125 // used to access /proc
126 static pid_t gettid();
127 static void set_createThread_lock(Mutex* lk) { _createThread_lock = lk; }
128 static Mutex* createThread_lock(void) { return _createThread_lock; }
129 static void hotspot_sigmask(Thread* thread);
130
131 static address initial_thread_stack_bottom(void) { return _initial_thread_stack_bottom; }
132 static uintptr_t initial_thread_stack_size(void) { return _initial_thread_stack_size; }
133 static bool is_initial_thread(void);
134
135 static int page_size(void) { return _page_size; }
136 static void set_page_size(int val) { _page_size = val; }
137
138 static int vm_default_page_size(void) { return _vm_default_page_size; }
139
140 static address ucontext_get_pc(ucontext_t* uc);
141 static intptr_t* ucontext_get_sp(ucontext_t* uc);
142 static intptr_t* ucontext_get_fp(ucontext_t* uc);
143
144 // For Analyzer Forte AsyncGetCallTrace profiling support:
145 //
146 // This interface should be declared in os_linux_i486.hpp, but
147 // that file provides extensions to the os class and not the
148 // Linux class.
149 static ExtendedPC fetch_frame_from_ucontext(Thread* thread, ucontext_t* uc,
150 intptr_t** ret_sp, intptr_t** ret_fp);
151
152 // This boolean allows users to forward their own non-matching signals
153 // to JVM_handle_linux_signal, harmlessly.
154 static bool signal_handlers_are_installed;
155
156 static int get_our_sigflags(int);
157 static void set_our_sigflags(int, int);
158 static void signal_sets_init();
159 static void install_signal_handlers();
160 static void set_signal_handler(int, bool);
161 static bool is_sig_ignored(int sig);
162
163 static sigset_t* unblocked_signals();
164 static sigset_t* vm_signals();
165 static sigset_t* allowdebug_blocked_signals();
166
167 // For signal-chaining
168 static struct sigaction *get_chained_signal_action(int sig);
169 static bool chained_handler(int sig, siginfo_t* siginfo, void* context);
170
171 // GNU libc and libpthread version strings
172 static const char *glibc_version() { return _glibc_version; }
173 static const char *libpthread_version() { return _libpthread_version; }
174
175 // NPTL or LinuxThreads?
176 static bool is_LinuxThreads() { return !_is_NPTL; }
177 static bool is_NPTL() { return _is_NPTL; }
178
179 // NPTL is always floating stack. LinuxThreads could be using floating
180 // stack or fixed stack.
181 static bool is_floating_stack() { return _is_floating_stack; }
182
183 static void libpthread_init();
184 static bool libnuma_init();
185 static void* libnuma_dlsym(void* handle, const char* name);
186 // Minimum stack size a thread can be created with (allowing
187 // the VM to completely create the thread and enter user code)
188 static size_t min_stack_allowed;
189
190 // Return default stack size or guard size for the specified thread type
191 static size_t default_stack_size(os::ThreadType thr_type);
192 static size_t default_guard_size(os::ThreadType thr_type);
193
194 static void capture_initial_stack(size_t max_size);
195
196 // Stack overflow handling
197 static bool manually_expand_stack(JavaThread * t, address addr);
198 static int max_register_window_saves_before_flushing();
199
200 // Real-time clock functions
201 static void clock_init(void);
202
203 // fast POSIX clocks support
204 static void fast_thread_clock_init(void);
205
206 static inline bool supports_monotonic_clock() {
207 return _clock_gettime != NULL;
208 }
209
210 static int clock_gettime(clockid_t clock_id, struct timespec *tp) {
211 return _clock_gettime ? _clock_gettime(clock_id, tp) : -1;
212 }
213
214 static int pthread_getcpuclockid(pthread_t tid, clockid_t *clock_id) {
215 return _pthread_getcpuclockid ? _pthread_getcpuclockid(tid, clock_id) : -1;
216 }
217
218 static bool supports_fast_thread_cpu_time() {
219 return _supports_fast_thread_cpu_time;
220 }
221
222 static jlong fast_thread_cpu_time(clockid_t clockid);
223
224 // Stack repair handling
225
226 // none present
227
228 // LinuxThreads work-around for 6292965
229 static int safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime);
230
231 private:
232 typedef int (*sched_getcpu_func_t)(void);
233 typedef int (*numa_node_to_cpus_func_t)(int node, unsigned long *buffer, int bufferlen);
234 typedef int (*numa_max_node_func_t)(void);
235 typedef int (*numa_available_func_t)(void);
236 typedef int (*numa_tonode_memory_func_t)(void *start, size_t size, int node);
237 typedef void (*numa_interleave_memory_func_t)(void *start, size_t size, unsigned long *nodemask);
238
239 static sched_getcpu_func_t _sched_getcpu;
240 static numa_node_to_cpus_func_t _numa_node_to_cpus;
241 static numa_max_node_func_t _numa_max_node;
242 static numa_available_func_t _numa_available;
243 static numa_tonode_memory_func_t _numa_tonode_memory;
244 static numa_interleave_memory_func_t _numa_interleave_memory;
245 static unsigned long* _numa_all_nodes;
246
247 static void set_sched_getcpu(sched_getcpu_func_t func) { _sched_getcpu = func; }
248 static void set_numa_node_to_cpus(numa_node_to_cpus_func_t func) { _numa_node_to_cpus = func; }
249 static void set_numa_max_node(numa_max_node_func_t func) { _numa_max_node = func; }
250 static void set_numa_available(numa_available_func_t func) { _numa_available = func; }
251 static void set_numa_tonode_memory(numa_tonode_memory_func_t func) { _numa_tonode_memory = func; }
252 static void set_numa_interleave_memory(numa_interleave_memory_func_t func) { _numa_interleave_memory = func; }
253 static void set_numa_all_nodes(unsigned long* ptr) { _numa_all_nodes = ptr; }
254 static int sched_getcpu_syscall(void);
255 public:
256 static int sched_getcpu() { return _sched_getcpu != NULL ? _sched_getcpu() : -1; }
257 static int numa_node_to_cpus(int node, unsigned long *buffer, int bufferlen) {
258 return _numa_node_to_cpus != NULL ? _numa_node_to_cpus(node, buffer, bufferlen) : -1;
259 }
260 static int numa_max_node() { return _numa_max_node != NULL ? _numa_max_node() : -1; }
261 static int numa_available() { return _numa_available != NULL ? _numa_available() : -1; }
262 static int numa_tonode_memory(void *start, size_t size, int node) {
263 return _numa_tonode_memory != NULL ? _numa_tonode_memory(start, size, node) : -1;
264 }
265 static void numa_interleave_memory(void *start, size_t size) {
266 if (_numa_interleave_memory != NULL && _numa_all_nodes != NULL) {
267 _numa_interleave_memory(start, size, _numa_all_nodes);
268 }
269 }
270 static int get_node_by_cpu(int cpu_id);
271 };
272
273
274 class PlatformEvent : public CHeapObj<mtInternal> {
275 private:
276 double CachePad [4] ; // increase odds that _mutex is sole occupant of cache line
277 volatile int _Event ;
278 volatile int _nParked ;
279 pthread_mutex_t _mutex [1] ;
280 pthread_cond_t _cond [1] ;
281 double PostPad [2] ;
282 Thread * _Assoc ;
283
284 public: // TODO-FIXME: make dtor private
285 ~PlatformEvent() { guarantee (0, "invariant") ; }
286
287 public:
288 PlatformEvent() {
289 int status;
290 status = pthread_cond_init (_cond, NULL);
291 assert_status(status == 0, status, "cond_init");
292 status = pthread_mutex_init (_mutex, NULL);
293 assert_status(status == 0, status, "mutex_init");
294 _Event = 0 ;
295 _nParked = 0 ;
296 _Assoc = NULL ;
297 }
298
299 // Use caution with reset() and fired() -- they may require MEMBARs
300 void reset() { _Event = 0 ; }
301 int fired() { return _Event; }
302 void park () ;
303 void unpark () ;
304 int TryPark () ;
305 int park (jlong millis) ;
306 void SetAssociation (Thread * a) { _Assoc = a ; }
307 } ;
308
309 class PlatformParker : public CHeapObj<mtInternal> {
310 protected:
311 pthread_mutex_t _mutex [1] ;
312 pthread_cond_t _cond [1] ;
313
314 public: // TODO-FIXME: make dtor private
315 ~PlatformParker() { guarantee (0, "invariant") ; }
316
317 public:
318 PlatformParker() {
319 int status;
320 status = pthread_cond_init (_cond, NULL);
321 assert_status(status == 0, status, "cond_init");
322 status = pthread_mutex_init (_mutex, NULL);
323 assert_status(status == 0, status, "mutex_init");
324 }
325 };
326
327 #endif // OS_LINUX_VM_OS_LINUX_HPP