--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/runtime/os.hpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,986 @@
+/*
+ * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#ifndef SHARE_VM_RUNTIME_OS_HPP
+#define SHARE_VM_RUNTIME_OS_HPP
+
+#include "jvmtifiles/jvmti.h"
+#include "prims/jvm.h"
+#include "runtime/extendedPC.hpp"
+#include "runtime/handles.hpp"
+#include "utilities/macros.hpp"
+#ifndef _WINDOWS
+# include <setjmp.h>
+#endif
+#ifdef __APPLE__
+# include <mach/mach_time.h>
+#endif
+
+class AgentLibrary;
+class frame;
+
+// os defines the interface to operating system; this includes traditional
+// OS services (time, I/O) as well as other functionality with system-
+// dependent code.
+
+typedef void (*dll_func)(...);
+
+class Thread;
+class JavaThread;
+class Event;
+class DLL;
+class FileHandle;
+class NativeCallStack;
+
+template<class E> class GrowableArray;
+
+// %%%%% Moved ThreadState, START_FN, OSThread to new osThread.hpp. -- Rose
+
+// Platform-independent error return values from OS functions
+enum OSReturn {
+ OS_OK = 0, // Operation was successful
+ OS_ERR = -1, // Operation failed
+ OS_INTRPT = -2, // Operation was interrupted
+ OS_TIMEOUT = -3, // Operation timed out
+ OS_NOMEM = -5, // Operation failed for lack of memory
+ OS_NORESOURCE = -6 // Operation failed for lack of nonmemory resource
+};
+
+enum ThreadPriority { // JLS 20.20.1-3
+ NoPriority = -1, // Initial non-priority value
+ MinPriority = 1, // Minimum priority
+ NormPriority = 5, // Normal (non-daemon) priority
+ NearMaxPriority = 9, // High priority, used for VMThread
+ MaxPriority = 10, // Highest priority, used for WatcherThread
+ // ensures that VMThread doesn't starve profiler
+ CriticalPriority = 11 // Critical thread priority
+};
+
+// Executable parameter flag for os::commit_memory() and
+// os::commit_memory_or_exit().
+const bool ExecMem = true;
+
+// Typedef for structured exception handling support
+typedef void (*java_call_t)(JavaValue* value, const methodHandle& method, JavaCallArguments* args, Thread* thread);
+
+class MallocTracker;
+
+class os: AllStatic {
+ friend class VMStructs;
+ friend class JVMCIVMStructs;
+ friend class MallocTracker;
+ public:
+ enum { page_sizes_max = 9 }; // Size of _page_sizes array (8 plus a sentinel)
+
+ private:
+ static OSThread* _starting_thread;
+ static address _polling_page;
+ static volatile int32_t * _mem_serialize_page;
+ static uintptr_t _serialize_page_mask;
+ public:
+ static size_t _page_sizes[page_sizes_max];
+
+ private:
+ static void init_page_sizes(size_t default_page_size) {
+ _page_sizes[0] = default_page_size;
+ _page_sizes[1] = 0; // sentinel
+ }
+
+ static char* pd_reserve_memory(size_t bytes, char* addr = 0,
+ size_t alignment_hint = 0);
+ static char* pd_attempt_reserve_memory_at(size_t bytes, char* addr);
+ static void pd_split_reserved_memory(char *base, size_t size,
+ size_t split, bool realloc);
+ static bool pd_commit_memory(char* addr, size_t bytes, bool executable);
+ static bool pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
+ bool executable);
+ // Same as pd_commit_memory() that either succeeds or calls
+ // vm_exit_out_of_memory() with the specified mesg.
+ static void pd_commit_memory_or_exit(char* addr, size_t bytes,
+ bool executable, const char* mesg);
+ static void pd_commit_memory_or_exit(char* addr, size_t size,
+ size_t alignment_hint,
+ bool executable, const char* mesg);
+ static bool pd_uncommit_memory(char* addr, size_t bytes);
+ static bool pd_release_memory(char* addr, size_t bytes);
+
+ static char* pd_map_memory(int fd, const char* file_name, size_t file_offset,
+ char *addr, size_t bytes, bool read_only = false,
+ bool allow_exec = false);
+ static char* pd_remap_memory(int fd, const char* file_name, size_t file_offset,
+ char *addr, size_t bytes, bool read_only,
+ bool allow_exec);
+ static bool pd_unmap_memory(char *addr, size_t bytes);
+ static void pd_free_memory(char *addr, size_t bytes, size_t alignment_hint);
+ static void pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint);
+
+ static size_t page_size_for_region(size_t region_size, size_t min_pages, bool must_be_aligned);
+
+ // Get summary strings for system information in buffer provided
+ static void get_summary_cpu_info(char* buf, size_t buflen);
+ static void get_summary_os_info(char* buf, size_t buflen);
+
+ static void initialize_initial_active_processor_count();
+ public:
+ static void init(void); // Called before command line parsing
+ static void init_before_ergo(void); // Called after command line parsing
+ // before VM ergonomics processing.
+ static jint init_2(void); // Called after command line parsing
+ // and VM ergonomics processing
+ static void init_globals(void) { // Called from init_globals() in init.cpp
+ init_globals_ext();
+ }
+
+ // File names are case-insensitive on windows only
+ // Override me as needed
+ static int file_name_strcmp(const char* s1, const char* s2);
+
+ // unset environment variable
+ static bool unsetenv(const char* name);
+
+ static bool have_special_privileges();
+
+ static jlong javaTimeMillis();
+ static jlong javaTimeNanos();
+ static void javaTimeNanos_info(jvmtiTimerInfo *info_ptr);
+ static void javaTimeSystemUTC(jlong &seconds, jlong &nanos);
+ static void run_periodic_checks();
+ static bool supports_monotonic_clock();
+
+ // Returns the elapsed time in seconds since the vm started.
+ static double elapsedTime();
+
+ // Returns real time in seconds since an arbitrary point
+ // in the past.
+ static bool getTimesSecs(double* process_real_time,
+ double* process_user_time,
+ double* process_system_time);
+
+ // Interface to the performance counter
+ static jlong elapsed_counter();
+ static jlong elapsed_frequency();
+
+ // The "virtual time" of a thread is the amount of time a thread has
+ // actually run. The first function indicates whether the OS supports
+ // this functionality for the current thread, and if so:
+ // * the second enables vtime tracking (if that is required).
+ // * the third tells whether vtime is enabled.
+ // * the fourth returns the elapsed virtual time for the current
+ // thread.
+ static bool supports_vtime();
+ static bool enable_vtime();
+ static bool vtime_enabled();
+ static double elapsedVTime();
+
+ // Return current local time in a string (YYYY-MM-DD HH:MM:SS).
+ // It is MT safe, but not async-safe, as reading time zone
+ // information may require a lock on some platforms.
+ static char* local_time_string(char *buf, size_t buflen);
+ static struct tm* localtime_pd (const time_t* clock, struct tm* res);
+ static struct tm* gmtime_pd (const time_t* clock, struct tm* res);
+ // Fill in buffer with current local time as an ISO-8601 string.
+ // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz.
+ // Returns buffer, or NULL if it failed.
+ static char* iso8601_time(char* buffer, size_t buffer_length, bool utc = false);
+
+ // Interface for detecting multiprocessor system
+ static inline bool is_MP() {
+ // During bootstrap if _processor_count is not yet initialized
+ // we claim to be MP as that is safest. If any platform has a
+ // stub generator that might be triggered in this phase and for
+ // which being declared MP when in fact not, is a problem - then
+ // the bootstrap routine for the stub generator needs to check
+ // the processor count directly and leave the bootstrap routine
+ // in place until called after initialization has ocurred.
+ return (_processor_count != 1) || AssumeMP;
+ }
+ static julong available_memory();
+ static julong physical_memory();
+ static bool has_allocatable_memory_limit(julong* limit);
+ static bool is_server_class_machine();
+
+ // number of CPUs
+ static int processor_count() {
+ return _processor_count;
+ }
+ static void set_processor_count(int count) { _processor_count = count; }
+
+ // Returns the number of CPUs this process is currently allowed to run on.
+ // Note that on some OSes this can change dynamically.
+ static int active_processor_count();
+
+ // At startup the number of active CPUs this process is allowed to run on.
+ // This value does not change dynamically. May be different from active_processor_count().
+ static int initial_active_processor_count() {
+ assert(_initial_active_processor_count > 0, "Initial active processor count not set yet.");
+ return _initial_active_processor_count;
+ }
+
+ // Bind processes to processors.
+ // This is a two step procedure:
+ // first you generate a distribution of processes to processors,
+ // then you bind processes according to that distribution.
+ // Compute a distribution for number of processes to processors.
+ // Stores the processor id's into the distribution array argument.
+ // Returns true if it worked, false if it didn't.
+ static bool distribute_processes(uint length, uint* distribution);
+ // Binds the current process to a processor.
+ // Returns true if it worked, false if it didn't.
+ static bool bind_to_processor(uint processor_id);
+
+ // Give a name to the current thread.
+ static void set_native_thread_name(const char *name);
+
+ // Interface for stack banging (predetect possible stack overflow for
+ // exception processing) There are guard pages, and above that shadow
+ // pages for stack overflow checking.
+ static bool uses_stack_guard_pages();
+ static bool must_commit_stack_guard_pages();
+ static void map_stack_shadow_pages(address sp);
+ static bool stack_shadow_pages_available(Thread *thread, const methodHandle& method, address sp);
+
+ // OS interface to Virtual Memory
+
+ // Return the default page size.
+ static int vm_page_size();
+
+ // Returns the page size to use for a region of memory.
+ // region_size / min_pages will always be greater than or equal to the
+ // returned value. The returned value will divide region_size.
+ static size_t page_size_for_region_aligned(size_t region_size, size_t min_pages);
+
+ // Returns the page size to use for a region of memory.
+ // region_size / min_pages will always be greater than or equal to the
+ // returned value. The returned value might not divide region_size.
+ static size_t page_size_for_region_unaligned(size_t region_size, size_t min_pages);
+
+ // Return the largest page size that can be used
+ static size_t max_page_size() {
+ // The _page_sizes array is sorted in descending order.
+ return _page_sizes[0];
+ }
+
+ // Methods for tracing page sizes returned by the above method.
+ // The region_{min,max}_size parameters should be the values
+ // passed to page_size_for_region() and page_size should be the result of that
+ // call. The (optional) base and size parameters should come from the
+ // ReservedSpace base() and size() methods.
+ static void trace_page_sizes(const char* str, const size_t* page_sizes, int count);
+ static void trace_page_sizes(const char* str,
+ const size_t region_min_size,
+ const size_t region_max_size,
+ const size_t page_size,
+ const char* base,
+ const size_t size);
+ static void trace_page_sizes_for_requested_size(const char* str,
+ const size_t requested_size,
+ const size_t page_size,
+ const size_t alignment,
+ const char* base,
+ const size_t size);
+
+ static int vm_allocation_granularity();
+ static char* reserve_memory(size_t bytes, char* addr = 0,
+ size_t alignment_hint = 0);
+ static char* reserve_memory(size_t bytes, char* addr,
+ size_t alignment_hint, MEMFLAGS flags);
+ static char* reserve_memory_aligned(size_t size, size_t alignment);
+ static char* attempt_reserve_memory_at(size_t bytes, char* addr);
+ static void split_reserved_memory(char *base, size_t size,
+ size_t split, bool realloc);
+ static bool commit_memory(char* addr, size_t bytes, bool executable);
+ static bool commit_memory(char* addr, size_t size, size_t alignment_hint,
+ bool executable);
+ // Same as commit_memory() that either succeeds or calls
+ // vm_exit_out_of_memory() with the specified mesg.
+ static void commit_memory_or_exit(char* addr, size_t bytes,
+ bool executable, const char* mesg);
+ static void commit_memory_or_exit(char* addr, size_t size,
+ size_t alignment_hint,
+ bool executable, const char* mesg);
+ static bool uncommit_memory(char* addr, size_t bytes);
+ static bool release_memory(char* addr, size_t bytes);
+
+ // Touch memory pages that cover the memory range from start to end (exclusive)
+ // to make the OS back the memory range with actual memory.
+ // Current implementation may not touch the last page if unaligned addresses
+ // are passed.
+ static void pretouch_memory(void* start, void* end, size_t page_size = vm_page_size());
+
+ enum ProtType { MEM_PROT_NONE, MEM_PROT_READ, MEM_PROT_RW, MEM_PROT_RWX };
+ static bool protect_memory(char* addr, size_t bytes, ProtType prot,
+ bool is_committed = true);
+
+ static bool guard_memory(char* addr, size_t bytes);
+ static bool unguard_memory(char* addr, size_t bytes);
+ static bool create_stack_guard_pages(char* addr, size_t bytes);
+ static bool pd_create_stack_guard_pages(char* addr, size_t bytes);
+ static bool remove_stack_guard_pages(char* addr, size_t bytes);
+
+ static char* map_memory(int fd, const char* file_name, size_t file_offset,
+ char *addr, size_t bytes, bool read_only = false,
+ bool allow_exec = false);
+ static char* remap_memory(int fd, const char* file_name, size_t file_offset,
+ char *addr, size_t bytes, bool read_only,
+ bool allow_exec);
+ static bool unmap_memory(char *addr, size_t bytes);
+ static void free_memory(char *addr, size_t bytes, size_t alignment_hint);
+ static void realign_memory(char *addr, size_t bytes, size_t alignment_hint);
+
+ // NUMA-specific interface
+ static bool numa_has_static_binding();
+ static bool numa_has_group_homing();
+ static void numa_make_local(char *addr, size_t bytes, int lgrp_hint);
+ static void numa_make_global(char *addr, size_t bytes);
+ static size_t numa_get_groups_num();
+ static size_t numa_get_leaf_groups(int *ids, size_t size);
+ static bool numa_topology_changed();
+ static int numa_get_group_id();
+
+ // Page manipulation
+ struct page_info {
+ size_t size;
+ int lgrp_id;
+ };
+ static bool get_page_info(char *start, page_info* info);
+ static char* scan_pages(char *start, char* end, page_info* page_expected, page_info* page_found);
+
+ static char* non_memory_address_word();
+ // reserve, commit and pin the entire memory region
+ static char* reserve_memory_special(size_t size, size_t alignment,
+ char* addr, bool executable);
+ static bool release_memory_special(char* addr, size_t bytes);
+ static void large_page_init();
+ static size_t large_page_size();
+ static bool can_commit_large_page_memory();
+ static bool can_execute_large_page_memory();
+
+ // OS interface to polling page
+ static address get_polling_page() { return _polling_page; }
+ static void set_polling_page(address page) { _polling_page = page; }
+ static bool is_poll_address(address addr) { return addr >= _polling_page && addr < (_polling_page + os::vm_page_size()); }
+ static void make_polling_page_unreadable();
+ static void make_polling_page_readable();
+
+ // Routines used to serialize the thread state without using membars
+ static void serialize_thread_states();
+
+ // Since we write to the serialize page from every thread, we
+ // want stores to be on unique cache lines whenever possible
+ // in order to minimize CPU cross talk. We pre-compute the
+ // amount to shift the thread* to make this offset unique to
+ // each thread.
+ static int get_serialize_page_shift_count() {
+ return SerializePageShiftCount;
+ }
+
+ static void set_serialize_page_mask(uintptr_t mask) {
+ _serialize_page_mask = mask;
+ }
+
+ static unsigned int get_serialize_page_mask() {
+ return _serialize_page_mask;
+ }
+
+ static void set_memory_serialize_page(address page);
+
+ static address get_memory_serialize_page() {
+ return (address)_mem_serialize_page;
+ }
+
+ static inline void write_memory_serialize_page(JavaThread *thread) {
+ uintptr_t page_offset = ((uintptr_t)thread >>
+ get_serialize_page_shift_count()) &
+ get_serialize_page_mask();
+ *(volatile int32_t *)((uintptr_t)_mem_serialize_page+page_offset) = 1;
+ }
+
+ static bool is_memory_serialize_page(JavaThread *thread, address addr) {
+ if (UseMembar) return false;
+ // Previously this function calculated the exact address of this
+ // thread's serialize page, and checked if the faulting address
+ // was equal. However, some platforms mask off faulting addresses
+ // to the page size, so now we just check that the address is
+ // within the page. This makes the thread argument unnecessary,
+ // but we retain the NULL check to preserve existing behavior.
+ if (thread == NULL) return false;
+ address page = (address) _mem_serialize_page;
+ return addr >= page && addr < (page + os::vm_page_size());
+ }
+
+ static void block_on_serialize_page_trap();
+
+ // threads
+
+ enum ThreadType {
+ vm_thread,
+ cgc_thread, // Concurrent GC thread
+ pgc_thread, // Parallel GC thread
+ java_thread, // Java, CodeCacheSweeper, JVMTIAgent and Service threads.
+ compiler_thread,
+ watcher_thread,
+ os_thread
+ };
+
+ static bool create_thread(Thread* thread,
+ ThreadType thr_type,
+ size_t req_stack_size = 0);
+ static bool create_main_thread(JavaThread* thread);
+ static bool create_attached_thread(JavaThread* thread);
+ static void pd_start_thread(Thread* thread);
+ static void start_thread(Thread* thread);
+
+ static void initialize_thread(Thread* thr);
+ static void free_thread(OSThread* osthread);
+
+ // thread id on Linux/64bit is 64bit, on Windows and Solaris, it's 32bit
+ static intx current_thread_id();
+ static int current_process_id();
+ static int sleep(Thread* thread, jlong ms, bool interruptable);
+ // Short standalone OS sleep suitable for slow path spin loop.
+ // Ignores Thread.interrupt() (so keep it short).
+ // ms = 0, will sleep for the least amount of time allowed by the OS.
+ static void naked_short_sleep(jlong ms);
+ static void infinite_sleep(); // never returns, use with CAUTION
+ static void naked_yield () ;
+ static OSReturn set_priority(Thread* thread, ThreadPriority priority);
+ static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority);
+
+ static void interrupt(Thread* thread);
+ static bool is_interrupted(Thread* thread, bool clear_interrupted);
+
+ static int pd_self_suspend_thread(Thread* thread);
+
+ static ExtendedPC fetch_frame_from_context(const void* ucVoid, intptr_t** sp, intptr_t** fp);
+ static frame fetch_frame_from_context(const void* ucVoid);
+ static frame fetch_frame_from_ucontext(Thread* thread, void* ucVoid);
+
+ static void breakpoint();
+ static bool start_debugging(char *buf, int buflen);
+
+ static address current_stack_pointer();
+ static address current_stack_base();
+ static size_t current_stack_size();
+
+ static void verify_stack_alignment() PRODUCT_RETURN;
+
+ static bool message_box(const char* title, const char* message);
+ static char* do_you_want_to_debug(const char* message);
+
+ // run cmd in a separate process and return its exit code; or -1 on failures
+ static int fork_and_exec(char *cmd);
+
+ // Call ::exit() on all platforms but Windows
+ static void exit(int num);
+
+ // Terminate the VM, but don't exit the process
+ static void shutdown();
+
+ // Terminate with an error. Default is to generate a core file on platforms
+ // that support such things. This calls shutdown() and then aborts.
+ static void abort(bool dump_core, void *siginfo, const void *context);
+ static void abort(bool dump_core = true);
+
+ // Die immediately, no exit hook, no abort hook, no cleanup.
+ static void die();
+
+ // File i/o operations
+ static const int default_file_open_flags();
+ static int open(const char *path, int oflag, int mode);
+ static FILE* open(int fd, const char* mode);
+ static int close(int fd);
+ static jlong lseek(int fd, jlong offset, int whence);
+ static char* native_path(char *path);
+ static int ftruncate(int fd, jlong length);
+ static int fsync(int fd);
+ static int available(int fd, jlong *bytes);
+ static int get_fileno(FILE* fp);
+ static void flockfile(FILE* fp);
+ static void funlockfile(FILE* fp);
+
+ static int compare_file_modified_times(const char* file1, const char* file2);
+
+ //File i/o operations
+
+ static size_t read(int fd, void *buf, unsigned int nBytes);
+ static size_t read_at(int fd, void *buf, unsigned int nBytes, jlong offset);
+ static size_t restartable_read(int fd, void *buf, unsigned int nBytes);
+ static size_t write(int fd, const void *buf, unsigned int nBytes);
+
+ // Reading directories.
+ static DIR* opendir(const char* dirname);
+ static int readdir_buf_size(const char *path);
+ static struct dirent* readdir(DIR* dirp, dirent* dbuf);
+ static int closedir(DIR* dirp);
+
+ // Dynamic library extension
+ static const char* dll_file_extension();
+
+ static const char* get_temp_directory();
+ static const char* get_current_directory(char *buf, size_t buflen);
+
+ // Builds the platform-specific name of a library.
+ // Returns false if the buffer is too small.
+ static bool dll_build_name(char* buffer, size_t size,
+ const char* fname);
+
+ // Builds a platform-specific full library path given an ld path and
+ // unadorned library name. Returns true if the buffer contains a full
+ // path to an existing file, false otherwise. If pathname is empty,
+ // uses the path to the current directory.
+ static bool dll_locate_lib(char* buffer, size_t size,
+ const char* pathname, const char* fname);
+
+ // Symbol lookup, find nearest function name; basically it implements
+ // dladdr() for all platforms. Name of the nearest function is copied
+ // to buf. Distance from its base address is optionally returned as offset.
+ // If function name is not found, buf[0] is set to '\0' and offset is
+ // set to -1 (if offset is non-NULL).
+ static bool dll_address_to_function_name(address addr, char* buf,
+ int buflen, int* offset,
+ bool demangle = true);
+
+ // Locate DLL/DSO. On success, full path of the library is copied to
+ // buf, and offset is optionally set to be the distance between addr
+ // and the library's base address. On failure, buf[0] is set to '\0'
+ // and offset is set to -1 (if offset is non-NULL).
+ static bool dll_address_to_library_name(address addr, char* buf,
+ int buflen, int* offset);
+
+ // Find out whether the pc is in the static code for jvm.dll/libjvm.so.
+ static bool address_is_in_vm(address addr);
+
+ // Loads .dll/.so and
+ // in case of error it checks if .dll/.so was built for the
+ // same architecture as HotSpot is running on
+ static void* dll_load(const char *name, char *ebuf, int ebuflen);
+
+ // lookup symbol in a shared library
+ static void* dll_lookup(void* handle, const char* name);
+
+ // Unload library
+ static void dll_unload(void *lib);
+
+ // Callback for loaded module information
+ // Input parameters:
+ // char* module_file_name,
+ // address module_base_addr,
+ // address module_top_addr,
+ // void* param
+ typedef int (*LoadedModulesCallbackFunc)(const char *, address, address, void *);
+
+ static int get_loaded_modules_info(LoadedModulesCallbackFunc callback, void *param);
+
+ // Return the handle of this process
+ static void* get_default_process_handle();
+
+ // Check for static linked agent library
+ static bool find_builtin_agent(AgentLibrary *agent_lib, const char *syms[],
+ size_t syms_len);
+
+ // Find agent entry point
+ static void *find_agent_function(AgentLibrary *agent_lib, bool check_lib,
+ const char *syms[], size_t syms_len);
+
+ // Write to stream
+ static int log_vsnprintf(char* buf, size_t len, const char* fmt, va_list args) ATTRIBUTE_PRINTF(3, 0);
+
+ // Get host name in buffer provided
+ static bool get_host_name(char* buf, size_t buflen);
+
+ // Print out system information; they are called by fatal error handler.
+ // Output format may be different on different platforms.
+ static void print_os_info(outputStream* st);
+ static void print_os_info_brief(outputStream* st);
+ static void print_cpu_info(outputStream* st, char* buf, size_t buflen);
+ static void pd_print_cpu_info(outputStream* st, char* buf, size_t buflen);
+ static void print_summary_info(outputStream* st, char* buf, size_t buflen);
+ static void print_memory_info(outputStream* st);
+ static void print_dll_info(outputStream* st);
+ static void print_environment_variables(outputStream* st, const char** env_list);
+ static void print_context(outputStream* st, const void* context);
+ static void print_register_info(outputStream* st, const void* context);
+ static void print_siginfo(outputStream* st, const void* siginfo);
+ static void print_signal_handlers(outputStream* st, char* buf, size_t buflen);
+ static void print_date_and_time(outputStream* st, char* buf, size_t buflen);
+
+ static void print_location(outputStream* st, intptr_t x, bool verbose = false);
+ static size_t lasterror(char *buf, size_t len);
+ static int get_last_error();
+
+ // Replacement for strerror().
+ // Will return the english description of the error (e.g. "File not found", as
+ // suggested in the POSIX standard.
+ // Will return "Unknown error" for an unknown errno value.
+ // Will not attempt to localize the returned string.
+ // Will always return a valid string which is a static constant.
+ // Will not change the value of errno.
+ static const char* strerror(int e);
+
+ // Will return the literalized version of the given errno (e.g. "EINVAL"
+ // for EINVAL).
+ // Will return "Unknown error" for an unknown errno value.
+ // Will always return a valid string which is a static constant.
+ // Will not change the value of errno.
+ static const char* errno_name(int e);
+
+ // Determines whether the calling process is being debugged by a user-mode debugger.
+ static bool is_debugger_attached();
+
+ // wait for a key press if PauseAtExit is set
+ static void wait_for_keypress_at_exit(void);
+
+ // The following two functions are used by fatal error handler to trace
+ // native (C) frames. They are not part of frame.hpp/frame.cpp because
+ // frame.hpp/cpp assume thread is JavaThread, and also because different
+ // OS/compiler may have different convention or provide different API to
+ // walk C frames.
+ //
+ // We don't attempt to become a debugger, so we only follow frames if that
+ // does not require a lookup in the unwind table, which is part of the binary
+ // file but may be unsafe to read after a fatal error. So on x86, we can
+ // only walk stack if %ebp is used as frame pointer; on ia64, it's not
+ // possible to walk C stack without having the unwind table.
+ static bool is_first_C_frame(frame *fr);
+ static frame get_sender_for_C_frame(frame *fr);
+
+ // return current frame. pc() and sp() are set to NULL on failure.
+ static frame current_frame();
+
+ static void print_hex_dump(outputStream* st, address start, address end, int unitsize);
+
+ // returns a string to describe the exception/signal;
+ // returns NULL if exception_code is not an OS exception/signal.
+ static const char* exception_name(int exception_code, char* buf, size_t buflen);
+
+ // Returns the signal number (e.g. 11) for a given signal name (SIGSEGV).
+ static int get_signal_number(const char* signal_name);
+
+ // Returns native Java library, loads if necessary
+ static void* native_java_library();
+
+ // Fills in path to jvm.dll/libjvm.so (used by the Disassembler)
+ static void jvm_path(char *buf, jint buflen);
+
+ // Returns true if we are running in a headless jre.
+ static bool is_headless_jre();
+
+ // JNI names
+ static void print_jni_name_prefix_on(outputStream* st, int args_size);
+ static void print_jni_name_suffix_on(outputStream* st, int args_size);
+
+ // Init os specific system properties values
+ static void init_system_properties_values();
+
+ // IO operations, non-JVM_ version.
+ static int stat(const char* path, struct stat* sbuf);
+ static bool dir_is_empty(const char* path);
+
+ // IO operations on binary files
+ static int create_binary_file(const char* path, bool rewrite_existing);
+ static jlong current_file_offset(int fd);
+ static jlong seek_to_file_offset(int fd, jlong offset);
+
+ // Retrieve native stack frames.
+ // Parameter:
+ // stack: an array to storage stack pointers.
+ // frames: size of above array.
+ // toSkip: number of stack frames to skip at the beginning.
+ // Return: number of stack frames captured.
+ static int get_native_stack(address* stack, int size, int toSkip = 0);
+
+ // General allocation (must be MT-safe)
+ static void* malloc (size_t size, MEMFLAGS flags, const NativeCallStack& stack);
+ static void* malloc (size_t size, MEMFLAGS flags);
+ static void* realloc (void *memblock, size_t size, MEMFLAGS flag, const NativeCallStack& stack);
+ static void* realloc (void *memblock, size_t size, MEMFLAGS flag);
+
+ static void free (void *memblock);
+ static char* strdup(const char *, MEMFLAGS flags = mtInternal); // Like strdup
+ // Like strdup, but exit VM when strdup() returns NULL
+ static char* strdup_check_oom(const char*, MEMFLAGS flags = mtInternal);
+
+#ifndef PRODUCT
+ static julong num_mallocs; // # of calls to malloc/realloc
+ static julong alloc_bytes; // # of bytes allocated
+ static julong num_frees; // # of calls to free
+ static julong free_bytes; // # of bytes freed
+#endif
+
+ // SocketInterface (ex HPI SocketInterface )
+ static int socket(int domain, int type, int protocol);
+ static int socket_close(int fd);
+ static int recv(int fd, char* buf, size_t nBytes, uint flags);
+ static int send(int fd, char* buf, size_t nBytes, uint flags);
+ static int raw_send(int fd, char* buf, size_t nBytes, uint flags);
+ static int connect(int fd, struct sockaddr* him, socklen_t len);
+ static struct hostent* get_host_by_name(char* name);
+
+ // Support for signals (see JVM_RaiseSignal, JVM_RegisterSignal)
+ static void signal_init(TRAPS);
+ static void signal_init_pd();
+ static void signal_notify(int signal_number);
+ static void* signal(int signal_number, void* handler);
+ static void signal_raise(int signal_number);
+ static int signal_wait();
+ static int signal_lookup();
+ static void* user_handler();
+ static void terminate_signal_thread();
+ static int sigexitnum_pd();
+
+ // random number generation
+ static int random(); // return 32bit pseudorandom number
+ static void init_random(unsigned int initval); // initialize random sequence
+
+ // Structured OS Exception support
+ static void os_exception_wrapper(java_call_t f, JavaValue* value, const methodHandle& method, JavaCallArguments* args, Thread* thread);
+
+ // On Posix compatible OS it will simply check core dump limits while on Windows
+ // it will check if dump file can be created. Check or prepare a core dump to be
+ // taken at a later point in the same thread in os::abort(). Use the caller
+ // provided buffer as a scratch buffer. The status message which will be written
+ // into the error log either is file location or a short error message, depending
+ // on the checking result.
+ static void check_dump_limit(char* buffer, size_t bufferSize);
+
+ // Get the default path to the core file
+ // Returns the length of the string
+ static int get_core_path(char* buffer, size_t bufferSize);
+
+ // JVMTI & JVM monitoring and management support
+ // The thread_cpu_time() and current_thread_cpu_time() are only
+ // supported if is_thread_cpu_time_supported() returns true.
+ // They are not supported on Solaris T1.
+
+ // Thread CPU Time - return the fast estimate on a platform
+ // On Solaris - call gethrvtime (fast) - user time only
+ // On Linux - fast clock_gettime where available - user+sys
+ // - otherwise: very slow /proc fs - user+sys
+ // On Windows - GetThreadTimes - user+sys
+ static jlong current_thread_cpu_time();
+ static jlong thread_cpu_time(Thread* t);
+
+ // Thread CPU Time with user_sys_cpu_time parameter.
+ //
+ // If user_sys_cpu_time is true, user+sys time is returned.
+ // Otherwise, only user time is returned
+ static jlong current_thread_cpu_time(bool user_sys_cpu_time);
+ static jlong thread_cpu_time(Thread* t, bool user_sys_cpu_time);
+
+ // Return a bunch of info about the timers.
+ // Note that the returned info for these two functions may be different
+ // on some platforms
+ static void current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
+ static void thread_cpu_time_info(jvmtiTimerInfo *info_ptr);
+
+ static bool is_thread_cpu_time_supported();
+
+ // System loadavg support. Returns -1 if load average cannot be obtained.
+ static int loadavg(double loadavg[], int nelem);
+
+ // Hook for os specific jvm options that we don't want to abort on seeing
+ static bool obsolete_option(const JavaVMOption *option);
+
+ // Amount beyond the callee frame size that we bang the stack.
+ static int extra_bang_size_in_bytes();
+
+ static char** split_path(const char* path, int* n);
+
+ // Extensions
+#include "runtime/os_ext.hpp"
+
+ public:
+ class CrashProtectionCallback : public StackObj {
+ public:
+ virtual void call() = 0;
+ };
+
+ // Platform dependent stuff
+#ifndef _WINDOWS
+# include "os_posix.hpp"
+#endif
+#include OS_CPU_HEADER(os)
+#include OS_HEADER(os)
+
+#ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG
+#define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: possibly out of memory or process/resource limits reached"
+#endif
+
+ public:
+#ifndef PLATFORM_PRINT_NATIVE_STACK
+ // No platform-specific code for printing the native stack.
+ static bool platform_print_native_stack(outputStream* st, const void* context,
+ char *buf, int buf_size) {
+ return false;
+ }
+#endif
+
+ // debugging support (mostly used by debug.cpp but also fatal error handler)
+ static bool find(address pc, outputStream* st = tty); // OS specific function to make sense out of an address
+
+ static bool dont_yield(); // when true, JVM_Yield() is nop
+ static void print_statistics();
+
+ // Thread priority helpers (implemented in OS-specific part)
+ static OSReturn set_native_priority(Thread* thread, int native_prio);
+ static OSReturn get_native_priority(const Thread* const thread, int* priority_ptr);
+ static int java_to_os_priority[CriticalPriority + 1];
+ // Hint to the underlying OS that a task switch would not be good.
+ // Void return because it's a hint and can fail.
+ static void hint_no_preempt();
+ static const char* native_thread_creation_failed_msg() {
+ return OS_NATIVE_THREAD_CREATION_FAILED_MSG;
+ }
+
+ // Used at creation if requested by the diagnostic flag PauseAtStartup.
+ // Causes the VM to wait until an external stimulus has been applied
+ // (for Unix, that stimulus is a signal, for Windows, an external
+ // ResumeThread call)
+ static void pause();
+
+ // Builds a platform dependent Agent_OnLoad_<libname> function name
+ // which is used to find statically linked in agents.
+ static char* build_agent_function_name(const char *sym, const char *cname,
+ bool is_absolute_path);
+
+ class SuspendedThreadTaskContext {
+ public:
+ SuspendedThreadTaskContext(Thread* thread, void *ucontext) : _thread(thread), _ucontext(ucontext) {}
+ Thread* thread() const { return _thread; }
+ void* ucontext() const { return _ucontext; }
+ private:
+ Thread* _thread;
+ void* _ucontext;
+ };
+
+ class SuspendedThreadTask {
+ public:
+ SuspendedThreadTask(Thread* thread) : _thread(thread), _done(false) {}
+ virtual ~SuspendedThreadTask() {}
+ void run();
+ bool is_done() { return _done; }
+ virtual void do_task(const SuspendedThreadTaskContext& context) = 0;
+ protected:
+ private:
+ void internal_do_task();
+ Thread* _thread;
+ bool _done;
+ };
+
+#ifndef _WINDOWS
+ // Suspend/resume support
+ // Protocol:
+ //
+ // a thread starts in SR_RUNNING
+ //
+ // SR_RUNNING can go to
+ // * SR_SUSPEND_REQUEST when the WatcherThread wants to suspend it
+ // SR_SUSPEND_REQUEST can go to
+ // * SR_RUNNING if WatcherThread decides it waited for SR_SUSPENDED too long (timeout)
+ // * SR_SUSPENDED if the stopped thread receives the signal and switches state
+ // SR_SUSPENDED can go to
+ // * SR_WAKEUP_REQUEST when the WatcherThread has done the work and wants to resume
+ // SR_WAKEUP_REQUEST can go to
+ // * SR_RUNNING when the stopped thread receives the signal
+ // * SR_WAKEUP_REQUEST on timeout (resend the signal and try again)
+ class SuspendResume {
+ public:
+ enum State {
+ SR_RUNNING,
+ SR_SUSPEND_REQUEST,
+ SR_SUSPENDED,
+ SR_WAKEUP_REQUEST
+ };
+
+ private:
+ volatile State _state;
+
+ private:
+ /* try to switch state from state "from" to state "to"
+ * returns the state set after the method is complete
+ */
+ State switch_state(State from, State to);
+
+ public:
+ SuspendResume() : _state(SR_RUNNING) { }
+
+ State state() const { return _state; }
+
+ State request_suspend() {
+ return switch_state(SR_RUNNING, SR_SUSPEND_REQUEST);
+ }
+
+ State cancel_suspend() {
+ return switch_state(SR_SUSPEND_REQUEST, SR_RUNNING);
+ }
+
+ State suspended() {
+ return switch_state(SR_SUSPEND_REQUEST, SR_SUSPENDED);
+ }
+
+ State request_wakeup() {
+ return switch_state(SR_SUSPENDED, SR_WAKEUP_REQUEST);
+ }
+
+ State running() {
+ return switch_state(SR_WAKEUP_REQUEST, SR_RUNNING);
+ }
+
+ bool is_running() const {
+ return _state == SR_RUNNING;
+ }
+
+ bool is_suspend_request() const {
+ return _state == SR_SUSPEND_REQUEST;
+ }
+
+ bool is_suspended() const {
+ return _state == SR_SUSPENDED;
+ }
+ };
+#endif // !WINDOWS
+
+
+ protected:
+ static volatile unsigned int _rand_seed; // seed for random number generator
+ static int _processor_count; // number of processors
+ static int _initial_active_processor_count; // number of active processors during initialization.
+
+ static char* format_boot_path(const char* format_string,
+ const char* home,
+ int home_len,
+ char fileSep,
+ char pathSep);
+ static bool set_boot_path(char fileSep, char pathSep);
+
+};
+
+// Note that "PAUSE" is almost always used with synchronization
+// so arguably we should provide Atomic::SpinPause() instead
+// of the global SpinPause() with C linkage.
+// It'd also be eligible for inlining on many platforms.
+
+extern "C" int SpinPause();
+
+#endif // SHARE_VM_RUNTIME_OS_HPP