os_linux.hpp revision 5143:4c84d351cca9 
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 */
31typedef int (*pthread_getattr_func_type) (pthread_t, pthread_attr_t *);
32
33class 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
231private:
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);
255public:
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
274class 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
309class 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
328