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
36 // For signal-chaining
37 #define MAXSIGNUM 32
38 static struct sigaction sigact[MAXSIGNUM]; // saved preinstalled sigactions
39 static unsigned int sigs; // mask of signals that have
40 // preinstalled signal handlers
41 static bool libjsig_is_loaded; // libjsig that interposes sigaction(),
42 // __sigaction(), signal() is loaded
43 static struct sigaction *(*get_signal_action)(int);
44 static struct sigaction *get_preinstalled_handler(int);
45 static void save_preinstalled_handler(int, struct sigaction&);
46
47 static void check_signal_handler(int sig);
48
49 // For signal flags diagnostics
50 static int sigflags[MAXSIGNUM];
51
52 static int (*_clock_gettime)(clockid_t, struct timespec *);
53 static int (*_pthread_getcpuclockid)(pthread_t, clockid_t *);
54
55 static address _initial_thread_stack_bottom;
56 static uintptr_t _initial_thread_stack_size;
57
58 static const char *_glibc_version;
59 static const char *_libpthread_version;
60
61 static bool _is_floating_stack;
62 static bool _is_NPTL;
63 static bool _supports_fast_thread_cpu_time;
64
65 static GrowableArray<int>* _cpu_to_node;
66
67 protected:
68
69 static julong _physical_memory;
70 static pthread_t _main_thread;
71 static Mutex* _createThread_lock;
72 static int _page_size;
73 static const int _vm_default_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 bool supports_variable_stack_size();
87
88 static void set_is_NPTL() { _is_NPTL = true; }
89 static void set_is_LinuxThreads() { _is_NPTL = false; }
90 static void set_is_floating_stack() { _is_floating_stack = true; }
91
92 static void rebuild_cpu_to_node_map();
93 static GrowableArray<int>* cpu_to_node() { return _cpu_to_node; }
94
95 static bool hugetlbfs_sanity_check(bool warn, size_t page_size);
96
97 static void print_full_memory_info(outputStream* st);
98 static void print_distro_info(outputStream* st);
99 static void print_libversion_info(outputStream* st);
100
101 public:
102 static bool _stack_is_executable;
103 static void *dlopen_helper(const char *name, char *ebuf, int ebuflen);
104 static void *dll_load_in_vmthread(const char *name, char *ebuf, int ebuflen);
105
106 static void init_thread_fpu_state();
107 static int get_fpu_control_word();
108 static void set_fpu_control_word(int fpu_control);
109 static pthread_t main_thread(void) { return _main_thread; }
110 // returns kernel thread id (similar to LWP id on Solaris), which can be
111 // used to access /proc
112 static pid_t gettid();
113 static void set_createThread_lock(Mutex* lk) { _createThread_lock = lk; }
114 static Mutex* createThread_lock(void) { return _createThread_lock; }
115 static void hotspot_sigmask(Thread* thread);
116
117 static address initial_thread_stack_bottom(void) { return _initial_thread_stack_bottom; }
118 static uintptr_t initial_thread_stack_size(void) { return _initial_thread_stack_size; }
119 static bool is_initial_thread(void);
120
121 static int page_size(void) { return _page_size; }
122 static void set_page_size(int val) { _page_size = val; }
123
124 static int vm_default_page_size(void) { return _vm_default_page_size; }
125
126 static address ucontext_get_pc(ucontext_t* uc);
127 static intptr_t* ucontext_get_sp(ucontext_t* uc);
128 static intptr_t* ucontext_get_fp(ucontext_t* uc);
129
130 // For Analyzer Forte AsyncGetCallTrace profiling support:
131 //
132 // This interface should be declared in os_linux_i486.hpp, but
133 // that file provides extensions to the os class and not the
134 // Linux class.
135 static ExtendedPC fetch_frame_from_ucontext(Thread* thread, ucontext_t* uc,
136 intptr_t** ret_sp, intptr_t** ret_fp);
137
138 // This boolean allows users to forward their own non-matching signals
139 // to JVM_handle_linux_signal, harmlessly.
140 static bool signal_handlers_are_installed;
141
142 static int get_our_sigflags(int);
143 static void set_our_sigflags(int, int);
144 static void signal_sets_init();
145 static void install_signal_handlers();
146 static void set_signal_handler(int, bool);
147 static bool is_sig_ignored(int sig);
148
149 static sigset_t* unblocked_signals();
150 static sigset_t* vm_signals();
151 static sigset_t* allowdebug_blocked_signals();
152
153 // For signal-chaining
154 static struct sigaction *get_chained_signal_action(int sig);
155 static bool chained_handler(int sig, siginfo_t* siginfo, void* context);
156
157 // GNU libc and libpthread version strings
158 static const char *glibc_version() { return _glibc_version; }
159 static const char *libpthread_version() { return _libpthread_version; }
160
161 // NPTL or LinuxThreads?
162 static bool is_LinuxThreads() { return !_is_NPTL; }
163 static bool is_NPTL() { return _is_NPTL; }
164
165 // NPTL is always floating stack. LinuxThreads could be using floating
166 // stack or fixed stack.
167 static bool is_floating_stack() { return _is_floating_stack; }
168
169 static void libpthread_init();
170 static bool libnuma_init();
171 static void* libnuma_dlsym(void* handle, const char* name);
172 // Minimum stack size a thread can be created with (allowing
173 // the VM to completely create the thread and enter user code)
174 static size_t min_stack_allowed;
175
176 // Return default stack size or guard size for the specified thread type
177 static size_t default_stack_size(os::ThreadType thr_type);
178 static size_t default_guard_size(os::ThreadType thr_type);
179
180 static void capture_initial_stack(size_t max_size);
181
182 // Stack overflow handling
183 static bool manually_expand_stack(JavaThread * t, address addr);
184 static int max_register_window_saves_before_flushing();
185
186 // Real-time clock functions
187 static void clock_init(void);
188
189 // fast POSIX clocks support
190 static void fast_thread_clock_init(void);
191
192 static inline bool supports_monotonic_clock() {
193 return _clock_gettime != NULL;
194 }
195
196 static int clock_gettime(clockid_t clock_id, struct timespec *tp) {
197 return _clock_gettime ? _clock_gettime(clock_id, tp) : -1;
198 }
199
200 static int pthread_getcpuclockid(pthread_t tid, clockid_t *clock_id) {
201 return _pthread_getcpuclockid ? _pthread_getcpuclockid(tid, clock_id) : -1;
202 }
203
204 static bool supports_fast_thread_cpu_time() {
205 return _supports_fast_thread_cpu_time;
206 }
207
208 static jlong fast_thread_cpu_time(clockid_t clockid);
209
210 // Stack repair handling
211
212 // none present
213
214 // LinuxThreads work-around for 6292965
215 static int safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime);
216
217 private:
218 typedef int (*sched_getcpu_func_t)(void);
219 typedef int (*numa_node_to_cpus_func_t)(int node, unsigned long *buffer, int bufferlen);
220 typedef int (*numa_max_node_func_t)(void);
221 typedef int (*numa_available_func_t)(void);
222 typedef int (*numa_tonode_memory_func_t)(void *start, size_t size, int node);
223 typedef void (*numa_interleave_memory_func_t)(void *start, size_t size, unsigned long *nodemask);
224
225 static sched_getcpu_func_t _sched_getcpu;
226 static numa_node_to_cpus_func_t _numa_node_to_cpus;
227 static numa_max_node_func_t _numa_max_node;
228 static numa_available_func_t _numa_available;
229 static numa_tonode_memory_func_t _numa_tonode_memory;
230 static numa_interleave_memory_func_t _numa_interleave_memory;
231 static unsigned long* _numa_all_nodes;
232
233 static void set_sched_getcpu(sched_getcpu_func_t func) { _sched_getcpu = func; }
234 static void set_numa_node_to_cpus(numa_node_to_cpus_func_t func) { _numa_node_to_cpus = func; }
235 static void set_numa_max_node(numa_max_node_func_t func) { _numa_max_node = func; }
236 static void set_numa_available(numa_available_func_t func) { _numa_available = func; }
237 static void set_numa_tonode_memory(numa_tonode_memory_func_t func) { _numa_tonode_memory = func; }
238 static void set_numa_interleave_memory(numa_interleave_memory_func_t func) { _numa_interleave_memory = func; }
239 static void set_numa_all_nodes(unsigned long* ptr) { _numa_all_nodes = ptr; }
240 static int sched_getcpu_syscall(void);
241 public:
242 static int sched_getcpu() { return _sched_getcpu != NULL ? _sched_getcpu() : -1; }
243 static int numa_node_to_cpus(int node, unsigned long *buffer, int bufferlen) {
244 return _numa_node_to_cpus != NULL ? _numa_node_to_cpus(node, buffer, bufferlen) : -1;
245 }
246 static int numa_max_node() { return _numa_max_node != NULL ? _numa_max_node() : -1; }
247 static int numa_available() { return _numa_available != NULL ? _numa_available() : -1; }
248 static int numa_tonode_memory(void *start, size_t size, int node) {
249 return _numa_tonode_memory != NULL ? _numa_tonode_memory(start, size, node) : -1;
250 }
251 static void numa_interleave_memory(void *start, size_t size) {
252 if (_numa_interleave_memory != NULL && _numa_all_nodes != NULL) {
253 _numa_interleave_memory(start, size, _numa_all_nodes);
254 }
255 }
256 static int get_node_by_cpu(int cpu_id);
257 };
258
259
260 class PlatformEvent : public CHeapObj<mtInternal> {
261 private:
262 double CachePad [4] ; // increase odds that _mutex is sole occupant of cache line
263 volatile int _Event ;
264 volatile int _nParked ;
265 pthread_mutex_t _mutex [1] ;
266 pthread_cond_t _cond [1] ;
267 double PostPad [2] ;
268 Thread * _Assoc ;
269
270 public: // TODO-FIXME: make dtor private
271 ~PlatformEvent() { guarantee (0, "invariant") ; }
272
273 public:
274 PlatformEvent() {
275 int status;
276 status = pthread_cond_init (_cond, NULL);
277 assert_status(status == 0, status, "cond_init");
278 status = pthread_mutex_init (_mutex, NULL);
279 assert_status(status == 0, status, "mutex_init");
280 _Event = 0 ;
281 _nParked = 0 ;
282 _Assoc = NULL ;
283 }
284
285 // Use caution with reset() and fired() -- they may require MEMBARs
286 void reset() { _Event = 0 ; }
287 int fired() { return _Event; }
288 void park () ;
289 void unpark () ;
290 int TryPark () ;
291 int park (jlong millis) ;
292 void SetAssociation (Thread * a) { _Assoc = a ; }
293 } ;
294
295 class PlatformParker : public CHeapObj<mtInternal> {
296 protected:
297 pthread_mutex_t _mutex [1] ;
298 pthread_cond_t _cond [1] ;
299
300 public: // TODO-FIXME: make dtor private
301 ~PlatformParker() { guarantee (0, "invariant") ; }
302
303 public:
304 PlatformParker() {
305 int status;
306 status = pthread_cond_init (_cond, NULL);
307 assert_status(status == 0, status, "cond_init");
308 status = pthread_mutex_init (_mutex, NULL);
309 assert_status(status == 0, status, "mutex_init");
310 }
311 };
312
313 #endif // OS_LINUX_VM_OS_LINUX_HPP