1 /*
2 * Copyright (c) 1999, 2014, 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 // Information about the protection of the page at address '0' on this os.
34 static bool zero_page_read_protected() { return true; }
35
36 class Linux {
37 friend class os;
38 friend class TestReserveMemorySpecial;
39
40 // For signal-chaining
41 #define MAXSIGNUM 32
42 static struct sigaction sigact[MAXSIGNUM]; // saved preinstalled sigactions
43 static unsigned int sigs; // mask of signals that have
44 // preinstalled signal handlers
45 static bool libjsig_is_loaded; // libjsig that interposes sigaction(),
46 // __sigaction(), signal() is loaded
47 static struct sigaction *(*get_signal_action)(int);
48 static struct sigaction *get_preinstalled_handler(int);
49 static void save_preinstalled_handler(int, struct sigaction&);
50
51 static void check_signal_handler(int sig);
52
53 // For signal flags diagnostics
54 static int sigflags[MAXSIGNUM];
55
56 static int (*_clock_gettime)(clockid_t, struct timespec *);
57 static int (*_pthread_getcpuclockid)(pthread_t, clockid_t *);
58 static int (*_pthread_setname_np)(pthread_t, const char*);
59
60 static address _initial_thread_stack_bottom;
61 static uintptr_t _initial_thread_stack_size;
62
63 static const char *_glibc_version;
64 static const char *_libpthread_version;
65
66 static bool _is_floating_stack;
67 static bool _is_NPTL;
68 static bool _supports_fast_thread_cpu_time;
69
70 static GrowableArray<int>* _cpu_to_node;
71
72 protected:
73
74 static julong _physical_memory;
75 static pthread_t _main_thread;
76 static Mutex* _createThread_lock;
77 static int _page_size;
78 static const int _vm_default_page_size;
79
80 static julong available_memory();
81 static julong physical_memory() { return _physical_memory; }
82 static void initialize_system_info();
83
84 static int commit_memory_impl(char* addr, size_t bytes, bool exec);
85 static int commit_memory_impl(char* addr, size_t bytes,
86 size_t alignment_hint, bool exec);
87
88 static void set_glibc_version(const char *s) { _glibc_version = s; }
89 static void set_libpthread_version(const char *s) { _libpthread_version = s; }
90
91 static bool supports_variable_stack_size();
92
93 static void set_is_NPTL() { _is_NPTL = true; }
94 static void set_is_LinuxThreads() { _is_NPTL = false; }
95 static void set_is_floating_stack() { _is_floating_stack = true; }
96
97 static void rebuild_cpu_to_node_map();
98 static GrowableArray<int>* cpu_to_node() { return _cpu_to_node; }
99
100 static size_t find_large_page_size();
101 static size_t setup_large_page_size();
102
103 static bool setup_large_page_type(size_t page_size);
104 static bool transparent_huge_pages_sanity_check(bool warn, size_t pages_size);
105 static bool hugetlbfs_sanity_check(bool warn, size_t page_size);
106
107 static char* reserve_memory_special_shm(size_t bytes, size_t alignment, char* req_addr, bool exec);
108 static char* reserve_memory_special_huge_tlbfs(size_t bytes, size_t alignment, char* req_addr, bool exec);
109 static char* reserve_memory_special_huge_tlbfs_only(size_t bytes, char* req_addr, bool exec);
110 static char* reserve_memory_special_huge_tlbfs_mixed(size_t bytes, size_t alignment, char* req_addr, bool exec);
111
112 static bool release_memory_special_impl(char* base, size_t bytes);
113 static bool release_memory_special_shm(char* base, size_t bytes);
114 static bool release_memory_special_huge_tlbfs(char* base, size_t bytes);
115
116 static void print_full_memory_info(outputStream* st);
117 static void print_distro_info(outputStream* st);
118 static void print_libversion_info(outputStream* st);
119
120 public:
121 static bool _stack_is_executable;
122 static void *dlopen_helper(const char *name, char *ebuf, int ebuflen);
123 static void *dll_load_in_vmthread(const char *name, char *ebuf, int ebuflen);
124
125 static void init_thread_fpu_state();
126 static int get_fpu_control_word();
127 static void set_fpu_control_word(int fpu_control);
128 static pthread_t main_thread(void) { return _main_thread; }
129 // returns kernel thread id (similar to LWP id on Solaris), which can be
130 // used to access /proc
131 static pid_t gettid();
132 static void set_createThread_lock(Mutex* lk) { _createThread_lock = lk; }
133 static Mutex* createThread_lock(void) { return _createThread_lock; }
134 static void hotspot_sigmask(Thread* thread);
135
136 static address initial_thread_stack_bottom(void) { return _initial_thread_stack_bottom; }
137 static uintptr_t initial_thread_stack_size(void) { return _initial_thread_stack_size; }
138 static bool is_initial_thread(void);
139
140 static int page_size(void) { return _page_size; }
141 static void set_page_size(int val) { _page_size = val; }
142
143 static int vm_default_page_size(void) { return _vm_default_page_size; }
144
145 static address ucontext_get_pc(ucontext_t* uc);
146 static void ucontext_set_pc(ucontext_t* uc, address pc);
147 static intptr_t* ucontext_get_sp(ucontext_t* uc);
148 static intptr_t* ucontext_get_fp(ucontext_t* uc);
149
150 // For Analyzer Forte AsyncGetCallTrace profiling support:
151 //
152 // This interface should be declared in os_linux_i486.hpp, but
153 // that file provides extensions to the os class and not the
154 // Linux class.
155 static ExtendedPC fetch_frame_from_ucontext(Thread* thread, ucontext_t* uc,
156 intptr_t** ret_sp, intptr_t** ret_fp);
157
158 // This boolean allows users to forward their own non-matching signals
159 // to JVM_handle_linux_signal, harmlessly.
160 static bool signal_handlers_are_installed;
161
162 static int get_our_sigflags(int);
163 static void set_our_sigflags(int, int);
164 static void signal_sets_init();
165 static void install_signal_handlers();
166 static void set_signal_handler(int, bool);
167 static bool is_sig_ignored(int sig);
168
169 static sigset_t* unblocked_signals();
170 static sigset_t* vm_signals();
171 static sigset_t* allowdebug_blocked_signals();
172
173 // For signal-chaining
174 static struct sigaction *get_chained_signal_action(int sig);
175 static bool chained_handler(int sig, siginfo_t* siginfo, void* context);
176
177 // GNU libc and libpthread version strings
178 static const char *glibc_version() { return _glibc_version; }
179 static const char *libpthread_version() { return _libpthread_version; }
180
181 // NPTL or LinuxThreads?
182 static bool is_LinuxThreads() { return !_is_NPTL; }
183 static bool is_NPTL() { return _is_NPTL; }
184
185 // NPTL is always floating stack. LinuxThreads could be using floating
186 // stack or fixed stack.
187 static bool is_floating_stack() { return _is_floating_stack; }
188
189 static void libpthread_init();
190 static bool libnuma_init();
191 static void* libnuma_dlsym(void* handle, const char* name);
192 // Minimum stack size a thread can be created with (allowing
193 // the VM to completely create the thread and enter user code)
194 static size_t min_stack_allowed;
195
196 // Return default stack size or guard size for the specified thread type
197 static size_t default_stack_size(os::ThreadType thr_type);
198 static size_t default_guard_size(os::ThreadType thr_type);
199
200 static void capture_initial_stack(size_t max_size);
201
202 // Stack overflow handling
203 static bool manually_expand_stack(JavaThread * t, address addr);
204 static int max_register_window_saves_before_flushing();
205
206 // Real-time clock functions
207 static void clock_init(void);
208
209 // fast POSIX clocks support
210 static void fast_thread_clock_init(void);
211
212 static int clock_gettime(clockid_t clock_id, struct timespec *tp) {
213 return _clock_gettime ? _clock_gettime(clock_id, tp) : -1;
214 }
215
216 static int pthread_getcpuclockid(pthread_t tid, clockid_t *clock_id) {
217 return _pthread_getcpuclockid ? _pthread_getcpuclockid(tid, clock_id) : -1;
218 }
219
220 static bool supports_fast_thread_cpu_time() {
221 return _supports_fast_thread_cpu_time;
222 }
223
224 static jlong fast_thread_cpu_time(clockid_t clockid);
225
226 // pthread_cond clock suppport
227 private:
228 static pthread_condattr_t _condattr[1];
229
230 public:
231 static pthread_condattr_t* condAttr() { return _condattr; }
232
233 // Stack repair handling
234
235 // none present
236
237 // LinuxThreads work-around for 6292965
238 static int safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime);
239
240 private:
241 typedef int (*sched_getcpu_func_t)(void);
242 typedef int (*numa_node_to_cpus_func_t)(int node, unsigned long *buffer, int bufferlen);
243 typedef int (*numa_max_node_func_t)(void);
244 typedef int (*numa_available_func_t)(void);
245 typedef int (*numa_tonode_memory_func_t)(void *start, size_t size, int node);
246 typedef void (*numa_interleave_memory_func_t)(void *start, size_t size, unsigned long *nodemask);
247 typedef void (*numa_set_bind_policy_func_t)(int policy);
248
249 static sched_getcpu_func_t _sched_getcpu;
250 static numa_node_to_cpus_func_t _numa_node_to_cpus;
251 static numa_max_node_func_t _numa_max_node;
252 static numa_available_func_t _numa_available;
253 static numa_tonode_memory_func_t _numa_tonode_memory;
254 static numa_interleave_memory_func_t _numa_interleave_memory;
255 static numa_set_bind_policy_func_t _numa_set_bind_policy;
256 static unsigned long* _numa_all_nodes;
257
258 static void set_sched_getcpu(sched_getcpu_func_t func) { _sched_getcpu = func; }
259 static void set_numa_node_to_cpus(numa_node_to_cpus_func_t func) { _numa_node_to_cpus = func; }
260 static void set_numa_max_node(numa_max_node_func_t func) { _numa_max_node = func; }
261 static void set_numa_available(numa_available_func_t func) { _numa_available = func; }
262 static void set_numa_tonode_memory(numa_tonode_memory_func_t func) { _numa_tonode_memory = func; }
263 static void set_numa_interleave_memory(numa_interleave_memory_func_t func) { _numa_interleave_memory = func; }
264 static void set_numa_set_bind_policy(numa_set_bind_policy_func_t func) { _numa_set_bind_policy = func; }
265 static void set_numa_all_nodes(unsigned long* ptr) { _numa_all_nodes = ptr; }
266 static int sched_getcpu_syscall(void);
267 public:
268 static int sched_getcpu() { return _sched_getcpu != NULL ? _sched_getcpu() : -1; }
269 static int numa_node_to_cpus(int node, unsigned long *buffer, int bufferlen) {
270 return _numa_node_to_cpus != NULL ? _numa_node_to_cpus(node, buffer, bufferlen) : -1;
271 }
272 static int numa_max_node() { return _numa_max_node != NULL ? _numa_max_node() : -1; }
273 static int numa_available() { return _numa_available != NULL ? _numa_available() : -1; }
274 static int numa_tonode_memory(void *start, size_t size, int node) {
275 return _numa_tonode_memory != NULL ? _numa_tonode_memory(start, size, node) : -1;
276 }
277 static void numa_interleave_memory(void *start, size_t size) {
278 if (_numa_interleave_memory != NULL && _numa_all_nodes != NULL) {
279 _numa_interleave_memory(start, size, _numa_all_nodes);
280 }
281 }
282 static void numa_set_bind_policy(int policy) {
283 if (_numa_set_bind_policy != NULL) {
284 _numa_set_bind_policy(policy);
285 }
286 }
287 static int get_node_by_cpu(int cpu_id);
288 };
289
290
291 class PlatformEvent : public CHeapObj<mtInternal> {
292 private:
293 double CachePad[4]; // increase odds that _mutex is sole occupant of cache line
294 volatile int _Event;
295 volatile int _nParked;
296 pthread_mutex_t _mutex[1];
297 pthread_cond_t _cond[1];
298 double PostPad[2];
299 Thread * _Assoc;
300
301 public: // TODO-FIXME: make dtor private
302 ~PlatformEvent() { guarantee(0, "invariant"); }
303
304 public:
305 PlatformEvent() {
306 int status;
307 status = pthread_cond_init(_cond, os::Linux::condAttr());
308 assert_status(status == 0, status, "cond_init");
309 status = pthread_mutex_init(_mutex, NULL);
310 assert_status(status == 0, status, "mutex_init");
311 _Event = 0;
312 _nParked = 0;
313 _Assoc = NULL;
314 }
315
316 // Use caution with reset() and fired() -- they may require MEMBARs
317 void reset() { _Event = 0; }
318 int fired() { return _Event; }
319 void park();
320 void unpark();
321 int park(jlong millis); // relative timed-wait only
322 void SetAssociation(Thread * a) { _Assoc = a; }
323 };
324
325 class PlatformParker : public CHeapObj<mtInternal> {
326 protected:
327 enum {
328 REL_INDEX = 0,
329 ABS_INDEX = 1
330 };
331 int _cur_index; // which cond is in use: -1, 0, 1
332 pthread_mutex_t _mutex[1];
333 pthread_cond_t _cond[2]; // one for relative times and one for abs.
334
335 public: // TODO-FIXME: make dtor private
336 ~PlatformParker() { guarantee(0, "invariant"); }
337
338 public:
339 PlatformParker() {
340 int status;
341 status = pthread_cond_init(&_cond[REL_INDEX], os::Linux::condAttr());
342 assert_status(status == 0, status, "cond_init rel");
343 status = pthread_cond_init(&_cond[ABS_INDEX], NULL);
344 assert_status(status == 0, status, "cond_init abs");
345 status = pthread_mutex_init(_mutex, NULL);
346 assert_status(status == 0, status, "mutex_init");
347 _cur_index = -1; // mark as unused
348 }
349 };
350
351 #endif // OS_LINUX_VM_OS_LINUX_HPP