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Quellcode-Bibliothek© Kompilation durch diese Firma[Weder Korrektheit noch Funktionsfähigkeit der Software werden zugesichert.]Datei: os.hpp Sprache: C |
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/*
* Copyright (c) 1997, 2022, 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_RUNTIME_OS_HPP #define SHARE_RUNTIME_OS_HPP #include "jvm_md.h" #include "metaprogramming/integralConstant.hpp" #include "runtime/osInfo.hpp" #include "utilities/exceptions.hpp" #include "utilities/ostream.hpp" #include "utilities/macros.hpp" #ifdef __APPLE__ # include <mach/mach_time.h> #endif class AgentLibrary; class frame; // Rules for using and implementing methods declared in the "os" class // =================================================================== // // The "os" class defines a number of the interfaces for porting HotSpot // to different operating systems. For example, I/O, memory, timing, etc. // Note that additional classes such as Semaphore, Mutex, etc., are used for // porting specific groups of features. // // Structure of os*.{cpp, hpp} files // // - os.hpp // // (This file) declares the entire API of the "os" class. // // - os.inline.hpp // // To use any of the inline methods declared in the "os" class, this // header file must be included. // // - src/hotspot/os/<os>/os_<os>.hpp // - src/hotspot/os/posix/os_posix.hpp // // These headers declare APIs that should be used only within the // platform-specific source files for that particular OS. // // For example, os_linux.hpp declares the os::Linux class, which provides // many methods that can be used by files under os/linux/ and os_cpu/linux_*/ // // os_posix.hpp can be used by platform-specific files for POSIX-like // OSes such as aix, bsd and linux. // // Platform-independent source files should not include these header files // (although sadly there are some rare exceptions ...) // // - os.cpp // // Platform-independent methods of the "os" class are defined // in os.cpp. These are not part of the porting interface, but rather // can be considered as convenience functions for accessing // the porting interface. E.g., os::print_function_and_library_name(). // // The methods declared in os.hpp but not implemented in os.cpp are // a part the HotSpot Porting APIs. They must be implemented in one of // the following four files: // // - src/hotspot/os/<os>/os_<os>.inline.hpp // - src/hotspot/os_cpu/<os>_<cpu>/os_<os>_<cpu>.inline.hpp // - src/hotspot/os/<os>/os_<os>.cpp // - src/hotspot/os_cpu/<os>_<cpu>/os_<os>_<cpu>.cpp // // The Porting APIs declared as "inline" in os.hpp MUST be // implemented in one of the two .inline.hpp files, depending on // whether the feature is specific to a particular CPU architecture // for this OS. These two files are automatically included by // os.inline.hpp. Platform-independent source files must not include // these two files directly. // // If the full definition of an inline method is too complex to fit in a // header file, the actual implementation can be deferred to another // method defined in the .cpp files. // // The Porting APIs that are *not* declared as "inline" in os.hpp MUST // be implemented in one of the two .cpp files above. These files // also implement OS-specific APIs such as os::Linux, os::Posix, etc. // // (Note: on the POSIX-like platforms, some of the Porting APIs are implemented // in os_posix.cpp instead). class Thread; class JavaThread; class NativeCallStack; class methodHandle; class OSThread; class Mutex; struct jvmtiTimerInfo; 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 }; enum WXMode { WXWrite, WXExec }; // 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, JavaCallA class MallocTracker; class os: AllStatic { friend class VMStructs; friend class JVMCIVMStructs; friend class MallocTracker; #ifdef ASSERT private: static bool _mutex_init_done; public: static void set_mutex_init_done() { _mutex_init_done = true; } static bool mutex_init_done() { return _mutex_init_done; } #endif public: // A simple value class holding a set of page sizes (similar to sigset_t) class PageSizes { size_t _v; // actually a bitmap. public: PageSizes() : _v(0) {} void add(size_t pagesize); bool contains(size_t pagesize) const; // Given a page size, return the next smaller page size in this set, or 0. size_t next_smaller(size_t pagesize) const; // Given a page size, return the next larger page size in this set, or 0. size_t next_larger(size_t pagesize) const; // Returns the largest page size in this set, or 0 if set is empty. size_t largest() const; // Returns the smallest page size in this set, or 0 if set is empty. size_t smallest() const; // Prints one line of comma separated, human readable page sizes, "empty" if empty. void print_on(outputStream* st) const; }; private: static OSThread* _starting_thread; static address _polling_page; static PageSizes _page_sizes; static char* pd_reserve_memory(size_t bytes, bool executable); static char* pd_attempt_reserve_memory_at(char* addr, size_t bytes, bool executable); 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, bool executable); static bool pd_release_memory(char* addr, size_t bytes); static char* pd_attempt_map_memory_to_file_at(char* addr, size_t bytes, int file_desc); 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 char* pd_reserve_memory_special(size_t size, size_t alignment, size_t page_size, char* addr, bool executable); static bool pd_release_memory_special(char* addr, size_t bytes); static size_t page_size_for_region(size_t region_size, size_t min_pages, bool must_be_a // 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(); LINUX_ONLY(static void pd_init_container_support();) public: static void init(void); // Called before command line parsing static void init_container_support() { // Called during command line parsing. LINUX_ONLY(pd_init_container_support();) } 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 // Get environ pointer, platform independently static char** get_environ(); 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(outputStream* st); // 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 // returns the elapsed virtual time for the current thread. static bool supports_vtime(); 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); // "YYYY-MM-DDThh:mm:ss.mmm+zzzz" incl. terminating zero static const size_t iso8601_timestamp_size = 29; // Fill in buffer with an ISO-8601 string corresponding to the given javaTimeMillis value // E.g., YYYY-MM-DDThh:mm:ss.mmm+zzzz. // Returns buffer, or NULL if it failed. static char* iso8601_time(jlong milliseconds_since_19700101, char* buffer, size_t buffer_length, bool utc = false); // 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 occurred. return (_processor_count != 1); } static julong available_memory(); static julong physical_memory(); static bool has_allocatable_memory_limit(size_t* limit); static bool is_server_class_machine(); // Returns the id of the processor on which the calling thread is currently executing. // The returned value is guaranteed to be between 0 and (os::processor_count() - 1). static uint processor_id(); // 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 return _initial_active_processor_count; } // 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. inline static bool uses_stack_guard_pages(); inline static bool must_commit_stack_guard_pages(); inline static void map_stack_shadow_pages(address sp); static bool stack_shadow_pages_available(Thread *thread, const methodHandle& metho private: // Minimum stack size a thread can be created with (allowing // the VM to completely create the thread and enter user code). // The initial values exclude any guard pages (by HotSpot or libc). // set_minimum_stack_sizes() will add the size required for // HotSpot guard pages depending on page size and flag settings. // Libc guard pages are never considered by these values. static size_t _compiler_thread_min_stack_allowed; static size_t _java_thread_min_stack_allowed; static size_t _vm_internal_thread_min_stack_allowed; static size_t _os_min_stack_allowed; // Check and sets minimum stack sizes static jint set_minimum_stack_sizes(); public: // Find committed memory region within specified range (start, start + size), // return true if found any static bool committed_in_range(address start, size_t size, address& committed_start // OS interface to Virtual Memory // Return the default page size. static int vm_page_size() { return OSInfo::vm_page_size(); } // The set of page sizes which the VM is allowed to use (may be a subset of // the page sizes actually available on the platform). static const PageSizes& page_sizes() { return _page_sizes; } // 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() { return page_sizes().largest(); } // Return a lower bound for page sizes. Also works before os::init completed. static size_t min_page_size() { return 4 * K; } // 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() { return OSInfo::vm_allocation_granularity(); } inline static size_t cds_core_region_alignment(); // Reserves virtual memory. static char* reserve_memory(size_t bytes, bool executable = false, MEMFLAGS flags = mtNone) // Reserves virtual memory that starts at an address that is aligned to 'alignment'. static char* reserve_memory_aligned(size_t size, size_t alignment, bool executable = fals // Attempts to reserve the virtual memory at [addr, addr + bytes). // Does not overwrite existing mappings. static char* attempt_reserve_memory_at(char* addr, size_t bytes, bool executable = false) 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, bool executable = false); static bool release_memory(char* addr, size_t bytes); // Does the platform support trimming the native heap? static bool can_trim_native_heap(); // Trim the C-heap. Optionally returns working set size change (RSS+Swap) in *rss_change. // Note: If trimming succeeded but no size change information could be obtained, // rss_change.after will contain SIZE_MAX upon return. struct size_change_t { size_t before; size_t after; }; static bool trim_native_heap(size_change_t* rss_change = nullptr); // A diagnostic function to print memory mappings in the given range. static void print_memory_mappings(char* addr, size_t bytes, outputStream* st); // Prints all mappings static void print_memory_mappings(outputStream* st); // Touch memory pages that cover the memory range from start to end // (exclusive) to make the OS back the memory range with actual memory. // Other threads may use the memory range concurrently with pretouch. 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); // Helper function to create a new file with template jvmheap.XXXXXX. // Returns a valid fd on success or else returns -1 static int create_file_for_heap(const char* dir); // Map memory to the file referred by fd. This function is slightly different from map_memory() // and is added to be used for implementation of -XX:AllocateHeapAt static char* map_memory_to_file(size_t size, int fd); static char* map_memory_to_file_aligned(size_t size, size_t alignment, int fd); static char* map_memory_to_file(char* base, size_t size, int fd); static char* attempt_map_memory_to_file_at(char* base, size_t size, int fd); // Replace existing reserved memory with file mapping static char* replace_existing_mapping_with_file_mapping(char* base, size_t size, int fd 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, MEMFLAGS flags = mtNone); 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(); static int numa_get_group_id_for_address(const void* address); // 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 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, size_t page_size, 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(); // Check if pointer points to readable memory (by 4-byte read access) static bool is_readable_pointer(const void* p); static bool is_readable_range(const void* from, const void* to); // threads enum ThreadType { vm_thread, gc_thread, // GC thread java_thread, // Java, JVMTIAgent and Service threads. compiler_thread, watcher_thread, asynclog_thread, // dedicated to flushing logs os_thread }; static bool create_thread(Thread* thread, ThreadType thr_type, size_t req_stack_size = 0); // The "main thread", also known as "starting thread", is the thread // that loads/creates the JVM via JNI_CreateJavaVM. static bool create_main_thread(JavaThread* thread); // The primordial thread is the initial process thread. The java // launcher never uses the primordial thread as the main thread, but // applications that host the JVM directly may do so. Some platforms // need special-case handling of the primordial thread if it attaches // to the VM. static bool is_primordial_thread(void) #if defined(_WINDOWS) || defined(BSD) // No way to identify the primordial thread. { return false; } #else ; #endif static bool create_attached_thread(JavaThread* thread); static void pd_start_thread(Thread* thread); static void start_thread(Thread* thread); // Returns true if successful. static bool signal_thread(Thread* thread, int sig, const char* reason); static void free_thread(OSThread* osthread); // thread id on Linux/64bit is 64bit, on Windows it's 32bit static intx current_thread_id(); static int current_process_id(); // Short standalone OS sleep routines suitable for slow path spin loop. // Ignores safepoints/suspension/Thread.interrupt() (so keep it short). // ms/ns = 0, will sleep for the least amount of time allowed by the OS. // Maximum sleep time is just under 1 second. static void naked_short_sleep(jlong ms); static void naked_short_nanosleep(jlong ns); // Longer standalone OS sleep routine - a convenience wrapper around // multiple calls to naked_short_sleep. Only for use by non-JavaThreads. static void naked_sleep(jlong millis); // Never returns, use with CAUTION static void infinite_sleep(); static void naked_yield () ; static OSReturn set_priority(Thread* thread, ThreadPriority priority); static OSReturn get_priority(const Thread* const thread, ThreadPriority& priority); static address 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_compiled_frame_from_context(const 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); // run cmd in a separate process and return its exit code; or -1 on failures. // Note: only safe to use in fatal error situations. static int fork_and_exec(const char *cmd); // Call ::exit() on all platforms static void exit(int num); // Call ::_exit() on all platforms. Similar semantics to die() except we never // want a core dump. 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. // Dump a core file, if possible, for debugging. os::abort() is the // preferred means to abort the VM on error. os::die() should only // be called if something has gone badly wrong. CreateCoredumpOnCrash // is intentionally not honored by this function. static void die(); // File i/o operations static int open(const char *path, int oflag, int mode); static FILE* fdopen(int fd, const char* mode); static FILE* fopen(const char* path, const char* mode); static jlong lseek(int fd, jlong offset, int whence); static bool file_exists(const char* file); // This function, on Windows, canonicalizes a given path (see os_windows.cpp for details). // On Posix, this function is a noop: it does not change anything and just returns // the input pointer. static char* native_path(char *path); static int ftruncate(int fd, jlong length); 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); static bool same_files(const char* file1, const char* file2); //File i/o operations static ssize_t read_at(int fd, void *buf, unsigned int nBytes, jlong offset); static ssize_t write(int fd, const void *buf, unsigned int nBytes); // Reading directories. static DIR* opendir(const char* dirname); static struct dirent* readdir(DIR* dirp); static int closedir(DIR* dirp); 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); // Given an address, attempt to locate both the symbol and the library it // resides in. If at least one of these steps was successful, prints information // and returns true. // - if no scratch buffer is given, stack is used // - shorten_paths: path is omitted from library name // - demangle: function name is demangled // - strip_arguments: arguments are stripped (requires demangle=true) // On success prints either one of: // "<function name>+<offset> in <library>" // "<function name>+<offset>" // "<address> in <library>+<offset>" static bool print_function_and_library_name(outputStream* st, address addr, char* buf = NULL, int buflen = 0, bool shorten_paths = true, bool demangle = true, bool strip_arguments = false); // Used only on PPC. inline static void* resolve_function_descriptor(void* p); // 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 // in case of an error NULL is returned and an error message is stored in ebuf 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); // Provide C99 compliant versions of these functions, since some versions // of some platforms don't. static int vsnprintf(char* buf, size_t len, const char* fmt, va_list args) ATTRIBUTE_PRINTF static int snprintf(char* buf, size_t len, const char* fmt, ...) ATTRIBUTE_PRINTF(3, 4); // 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_tos_pc(outputStream* st, const void* context); static void print_tos(outputStream* st, address sp); static void print_instructions(outputStream* st, address pc, int unitsize); static void print_register_info(outputStream* st, const void* context); static bool signal_sent_by_kill(const void* siginfo); 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_user_info(outputStream* st); static void print_active_locale(outputStream* st); // helper for output of seconds in days , hours and months static void print_dhm(outputStream* st, const char* startStr, long sec); 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); // 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, int bytes_per_line, address logical_start); static void print_hex_dump(outputStream* st, address start, address end, int unitsize) { print_hex_dump(st, start, end, unitsize, /*bytes_per_line=*/16, /*logical_start=*/sta } // 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); // 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&&nbs static void* realloc (void *memblock, size_t size, MEMFLAGS flag); // handles NULL pointers 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); // SocketInterface (ex HPI SocketInterface ) 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 static void initialize_jdk_signal_support(TRAPS); static void signal_notify(int signal_number); static int signal_wait(); static void terminate_signal_thread(); static int sigexitnum_pd(); // random number generation static int random(); // return 32bit pseudorandom number static int next_random(unsigned int rand_seed); // pure version of random() 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&&nbs // 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. // Thread CPU Time - return the fast estimate on a platform // 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); // 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, size_t* elements, size_t file_name_length); // support for mapping non-volatile memory using MAP_SYNC static bool supports_map_sync(); public: // File conventions static const char* file_separator(); static const char* line_separator(); static const char* path_separator(); // Information about the protection of the page at address '0' on this os. inline static bool zero_page_read_protected(); static void setup_fpu(); static juint cpu_microcode_revision(); static inline jlong rdtsc(); // Used to register dynamic code cache area with the OS // Note: Currently only used in 64 bit Windows implementations inline static bool register_code_area(char *low, char *high); // Platform-specific code for interacting with individual OSes. // TODO: This is for compatibility only with current usage of os::Linux, etc. // We can get rid of the following block if we rename such a class to something // like ::LinuxUtils #if defined(AIX) class Aix; #elif defined(BSD) class Bsd; #elif defined(LINUX) class Linux; #elif defined(_WINDOWS) class win32; #endif // Ditto - Posix-specific API. Ideally should be moved to something like ::PosixUtils. #ifndef _WINDOWS class Posix; #endif // FIXME - some random stuff that was in os_windows.hpp #ifdef _WINDOWS // strtok_s is the Windows thread-safe equivalent of POSIX strtok_r # define strtok_r strtok_s # define S_ISCHR(mode) (((mode) & _S_IFCHR) == _S_IFCHR) # define S_ISFIFO(mode) (((mode) & _S_IFIFO) == _S_IFIFO) #endif #ifndef OS_NATIVE_THREAD_CREATION_FAILED_MSG #define OS_NATIVE_THREAD_CREATION_FAILED_MSG "unable to create native thread: poss #endif public: inline static bool platform_print_native_stack(outputStream* st, const void* context, char *buf, int buf_size); // 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 static bool dont_yield(); // when true, JVM_Yield() is nop // 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 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); #if defined(__APPLE__) && defined(AARCH64) // Enables write or execute access to writeable and executable pages. static void current_thread_enable_wx(WXMode mode); #endif // __APPLE__ && AARCH64 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 initial 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_RUNTIME_OS_HPP ¤ Dauer der Verarbeitung: 0.40 Sekunden (vorverarbeitet) ¤ |
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