os_linux.hpp revision 6604:a2f5d920638e 
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 */
31typedef 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.
34static bool zero_page_read_protected() { return true; }
35
36class 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
59  static address   _initial_thread_stack_bottom;
60  static uintptr_t _initial_thread_stack_size;
61
62  static const char *_glibc_version;
63  static const char *_libpthread_version;
64
65  static bool _is_floating_stack;
66  static bool _is_NPTL;
67  static bool _supports_fast_thread_cpu_time;
68
69  static GrowableArray<int>* _cpu_to_node;
70
71 protected:
72
73  static julong _physical_memory;
74  static pthread_t _main_thread;
75  static Mutex* _createThread_lock;
76  static int _page_size;
77  static const int _vm_default_page_size;
78
79  static julong available_memory();
80  static julong physical_memory() { return _physical_memory; }
81  static void initialize_system_info();
82
83  static int commit_memory_impl(char* addr, size_t bytes, bool exec);
84  static int commit_memory_impl(char* addr, size_t bytes,
85                                size_t alignment_hint, bool exec);
86
87  static void set_glibc_version(const char *s)      { _glibc_version = s; }
88  static void set_libpthread_version(const char *s) { _libpthread_version = s; }
89
90  static bool supports_variable_stack_size();
91
92  static void set_is_NPTL()                   { _is_NPTL = true;  }
93  static void set_is_LinuxThreads()           { _is_NPTL = false; }
94  static void set_is_floating_stack()         { _is_floating_stack = true; }
95
96  static void rebuild_cpu_to_node_map();
97  static GrowableArray<int>* cpu_to_node()    { return _cpu_to_node; }
98
99  static size_t find_large_page_size();
100  static size_t setup_large_page_size();
101
102  static bool setup_large_page_type(size_t page_size);
103  static bool transparent_huge_pages_sanity_check(bool warn, size_t pages_size);
104  static bool hugetlbfs_sanity_check(bool warn, size_t page_size);
105
106  static char* reserve_memory_special_shm(size_t bytes, size_t alignment, char* req_addr, bool exec);
107  static char* reserve_memory_special_huge_tlbfs(size_t bytes, size_t alignment, char* req_addr, bool exec);
108  static char* reserve_memory_special_huge_tlbfs_only(size_t bytes, char* req_addr, bool exec);
109  static char* reserve_memory_special_huge_tlbfs_mixed(size_t bytes, size_t alignment, char* req_addr, bool exec);
110
111  static bool release_memory_special_shm(char* base, size_t bytes);
112  static bool release_memory_special_huge_tlbfs(char* base, size_t bytes);
113
114  static void print_full_memory_info(outputStream* st);
115  static void print_distro_info(outputStream* st);
116  static void print_libversion_info(outputStream* st);
117
118 public:
119  static bool _stack_is_executable;
120  static void *dlopen_helper(const char *name, char *ebuf, int ebuflen);
121  static void *dll_load_in_vmthread(const char *name, char *ebuf, int ebuflen);
122
123  static void init_thread_fpu_state();
124  static int  get_fpu_control_word();
125  static void set_fpu_control_word(int fpu_control);
126  static pthread_t main_thread(void)                                { return _main_thread; }
127  // returns kernel thread id (similar to LWP id on Solaris), which can be
128  // used to access /proc
129  static pid_t gettid();
130  static void set_createThread_lock(Mutex* lk)                      { _createThread_lock = lk; }
131  static Mutex* createThread_lock(void)                             { return _createThread_lock; }
132  static void hotspot_sigmask(Thread* thread);
133
134  static address   initial_thread_stack_bottom(void)                { return _initial_thread_stack_bottom; }
135  static uintptr_t initial_thread_stack_size(void)                  { return _initial_thread_stack_size; }
136  static bool is_initial_thread(void);
137
138  static int page_size(void)                                        { return _page_size; }
139  static void set_page_size(int val)                                { _page_size = val; }
140
141  static int vm_default_page_size(void)                             { return _vm_default_page_size; }
142
143  static address   ucontext_get_pc(ucontext_t* uc);
144  static intptr_t* ucontext_get_sp(ucontext_t* uc);
145  static intptr_t* ucontext_get_fp(ucontext_t* uc);
146
147  // For Analyzer Forte AsyncGetCallTrace profiling support:
148  //
149  // This interface should be declared in os_linux_i486.hpp, but
150  // that file provides extensions to the os class and not the
151  // Linux class.
152  static ExtendedPC fetch_frame_from_ucontext(Thread* thread, ucontext_t* uc,
153    intptr_t** ret_sp, intptr_t** ret_fp);
154
155  // This boolean allows users to forward their own non-matching signals
156  // to JVM_handle_linux_signal, harmlessly.
157  static bool signal_handlers_are_installed;
158
159  static int get_our_sigflags(int);
160  static void set_our_sigflags(int, int);
161  static void signal_sets_init();
162  static void install_signal_handlers();
163  static void set_signal_handler(int, bool);
164  static bool is_sig_ignored(int sig);
165
166  static sigset_t* unblocked_signals();
167  static sigset_t* vm_signals();
168  static sigset_t* allowdebug_blocked_signals();
169
170  // For signal-chaining
171  static struct sigaction *get_chained_signal_action(int sig);
172  static bool chained_handler(int sig, siginfo_t* siginfo, void* context);
173
174  // GNU libc and libpthread version strings
175  static const char *glibc_version()          { return _glibc_version; }
176  static const char *libpthread_version()     { return _libpthread_version; }
177
178  // NPTL or LinuxThreads?
179  static bool is_LinuxThreads()               { return !_is_NPTL; }
180  static bool is_NPTL()                       { return _is_NPTL;  }
181
182  // NPTL is always floating stack. LinuxThreads could be using floating
183  // stack or fixed stack.
184  static bool is_floating_stack()             { return _is_floating_stack; }
185
186  static void libpthread_init();
187  static bool libnuma_init();
188  static void* libnuma_dlsym(void* handle, const char* name);
189  // Minimum stack size a thread can be created with (allowing
190  // the VM to completely create the thread and enter user code)
191  static size_t min_stack_allowed;
192
193  // Return default stack size or guard size for the specified thread type
194  static size_t default_stack_size(os::ThreadType thr_type);
195  static size_t default_guard_size(os::ThreadType thr_type);
196
197  static void capture_initial_stack(size_t max_size);
198
199  // Stack overflow handling
200  static bool manually_expand_stack(JavaThread * t, address addr);
201  static int max_register_window_saves_before_flushing();
202
203  // Real-time clock functions
204  static void clock_init(void);
205
206  // fast POSIX clocks support
207  static void fast_thread_clock_init(void);
208
209  static int clock_gettime(clockid_t clock_id, struct timespec *tp) {
210    return _clock_gettime ? _clock_gettime(clock_id, tp) : -1;
211  }
212
213  static int pthread_getcpuclockid(pthread_t tid, clockid_t *clock_id) {
214    return _pthread_getcpuclockid ? _pthread_getcpuclockid(tid, clock_id) : -1;
215  }
216
217  static bool supports_fast_thread_cpu_time() {
218    return _supports_fast_thread_cpu_time;
219  }
220
221  static jlong fast_thread_cpu_time(clockid_t clockid);
222
223  // pthread_cond clock suppport
224  private:
225  static pthread_condattr_t _condattr[1];
226
227  public:
228  static pthread_condattr_t* condAttr() { return _condattr; }
229
230  // Stack repair handling
231
232  // none present
233
234  // LinuxThreads work-around for 6292965
235  static int safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime);
236
237private:
238  typedef int (*sched_getcpu_func_t)(void);
239  typedef int (*numa_node_to_cpus_func_t)(int node, unsigned long *buffer, int bufferlen);
240  typedef int (*numa_max_node_func_t)(void);
241  typedef int (*numa_available_func_t)(void);
242  typedef int (*numa_tonode_memory_func_t)(void *start, size_t size, int node);
243  typedef void (*numa_interleave_memory_func_t)(void *start, size_t size, unsigned long *nodemask);
244  typedef void (*numa_set_bind_policy_func_t)(int policy);
245
246  static sched_getcpu_func_t _sched_getcpu;
247  static numa_node_to_cpus_func_t _numa_node_to_cpus;
248  static numa_max_node_func_t _numa_max_node;
249  static numa_available_func_t _numa_available;
250  static numa_tonode_memory_func_t _numa_tonode_memory;
251  static numa_interleave_memory_func_t _numa_interleave_memory;
252  static numa_set_bind_policy_func_t _numa_set_bind_policy;
253  static unsigned long* _numa_all_nodes;
254
255  static void set_sched_getcpu(sched_getcpu_func_t func) { _sched_getcpu = func; }
256  static void set_numa_node_to_cpus(numa_node_to_cpus_func_t func) { _numa_node_to_cpus = func; }
257  static void set_numa_max_node(numa_max_node_func_t func) { _numa_max_node = func; }
258  static void set_numa_available(numa_available_func_t func) { _numa_available = func; }
259  static void set_numa_tonode_memory(numa_tonode_memory_func_t func) { _numa_tonode_memory = func; }
260  static void set_numa_interleave_memory(numa_interleave_memory_func_t func) { _numa_interleave_memory = func; }
261  static void set_numa_set_bind_policy(numa_set_bind_policy_func_t func) { _numa_set_bind_policy = func; }
262  static void set_numa_all_nodes(unsigned long* ptr) { _numa_all_nodes = ptr; }
263  static int sched_getcpu_syscall(void);
264public:
265  static int sched_getcpu()  { return _sched_getcpu != NULL ? _sched_getcpu() : -1; }
266  static int numa_node_to_cpus(int node, unsigned long *buffer, int bufferlen) {
267    return _numa_node_to_cpus != NULL ? _numa_node_to_cpus(node, buffer, bufferlen) : -1;
268  }
269  static int numa_max_node() { return _numa_max_node != NULL ? _numa_max_node() : -1; }
270  static int numa_available() { return _numa_available != NULL ? _numa_available() : -1; }
271  static int numa_tonode_memory(void *start, size_t size, int node) {
272    return _numa_tonode_memory != NULL ? _numa_tonode_memory(start, size, node) : -1;
273  }
274  static void numa_interleave_memory(void *start, size_t size) {
275    if (_numa_interleave_memory != NULL && _numa_all_nodes != NULL) {
276      _numa_interleave_memory(start, size, _numa_all_nodes);
277    }
278  }
279  static void numa_set_bind_policy(int policy) {
280    if (_numa_set_bind_policy != NULL) {
281      _numa_set_bind_policy(policy);
282    }
283  }
284  static int get_node_by_cpu(int cpu_id);
285};
286
287
288class PlatformEvent : public CHeapObj<mtInternal> {
289  private:
290    double CachePad[4];   // increase odds that _mutex is sole occupant of cache line
291    volatile int _Event;
292    volatile int _nParked;
293    pthread_mutex_t _mutex[1];
294    pthread_cond_t  _cond[1];
295    double PostPad[2];
296    Thread * _Assoc;
297
298  public:       // TODO-FIXME: make dtor private
299    ~PlatformEvent() { guarantee(0, "invariant"); }
300
301  public:
302    PlatformEvent() {
303      int status;
304      status = pthread_cond_init (_cond, os::Linux::condAttr());
305      assert_status(status == 0, status, "cond_init");
306      status = pthread_mutex_init (_mutex, NULL);
307      assert_status(status == 0, status, "mutex_init");
308      _Event   = 0;
309      _nParked = 0;
310      _Assoc   = NULL;
311    }
312
313    // Use caution with reset() and fired() -- they may require MEMBARs
314    void reset() { _Event = 0; }
315    int  fired() { return _Event; }
316    void park();
317    void unpark();
318    int  TryPark();
319    int  park(jlong millis); // relative timed-wait only
320    void SetAssociation(Thread * a) { _Assoc = a; }
321};
322
323class PlatformParker : public CHeapObj<mtInternal> {
324  protected:
325    enum {
326        REL_INDEX = 0,
327        ABS_INDEX = 1
328    };
329    int _cur_index;  // which cond is in use: -1, 0, 1
330    pthread_mutex_t _mutex[1];
331    pthread_cond_t  _cond[2]; // one for relative times and one for abs.
332
333  public:       // TODO-FIXME: make dtor private
334    ~PlatformParker() { guarantee(0, "invariant"); }
335
336  public:
337    PlatformParker() {
338      int status;
339      status = pthread_cond_init (&_cond[REL_INDEX], os::Linux::condAttr());
340      assert_status(status == 0, status, "cond_init rel");
341      status = pthread_cond_init (&_cond[ABS_INDEX], NULL);
342      assert_status(status == 0, status, "cond_init abs");
343      status = pthread_mutex_init (_mutex, NULL);
344      assert_status(status == 0, status, "mutex_init");
345      _cur_index = -1; // mark as unused
346    }
347};
348
349#endif // OS_LINUX_VM_OS_LINUX_HPP
350