/*
* Copyright (c) 1999, 2010, 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 OS_LINUX_VM_OS_LINUX_HPP
#define OS_LINUX_VM_OS_LINUX_HPP
// Linux_OS defines the interface to Linux operating systems
/* pthread_getattr_np comes with LinuxThreads-0.9-7 on RedHat 7.1 */
typedef int (*pthread_getattr_func_type) (pthread_t, pthread_attr_t *);
class Linux {
friend class os;
// For signal-chaining
#define MAXSIGNUM 32
static struct sigaction sigact[MAXSIGNUM]; // saved preinstalled sigactions
static unsigned int sigs; // mask of signals that have
// preinstalled signal handlers
static bool libjsig_is_loaded; // libjsig that interposes sigaction(),
// __sigaction(), signal() is loaded
static struct sigaction *(*get_signal_action)(int);
static struct sigaction *get_preinstalled_handler(int);
static void save_preinstalled_handler(int, struct sigaction&);
static void check_signal_handler(int sig);
// For signal flags diagnostics
static int sigflags[MAXSIGNUM];
static int (*_clock_gettime)(clockid_t, struct timespec *);
static int (*_pthread_getcpuclockid)(pthread_t, clockid_t *);
static address _initial_thread_stack_bottom;
static uintptr_t _initial_thread_stack_size;
static const char *_glibc_version;
static const char *_libpthread_version;
static bool _is_floating_stack;
static bool _is_NPTL;
static bool _supports_fast_thread_cpu_time;
static GrowableArray<int>* _cpu_to_node;
protected:
static julong _physical_memory;
static pthread_t _main_thread;
static Mutex* _createThread_lock;
static int _page_size;
static julong available_memory();
static julong physical_memory() { return _physical_memory; }
static void initialize_system_info();
static void set_glibc_version(const char *s) { _glibc_version = s; }
static void set_libpthread_version(const char *s) { _libpthread_version = s; }
static bool supports_variable_stack_size();
static void set_is_NPTL() { _is_NPTL = true; }
static void set_is_LinuxThreads() { _is_NPTL = false; }
static void set_is_floating_stack() { _is_floating_stack = true; }
static void rebuild_cpu_to_node_map();
static GrowableArray<int>* cpu_to_node() { return _cpu_to_node; }
static bool hugetlbfs_sanity_check(bool warn, size_t page_size);
public:
static void init_thread_fpu_state();
static int get_fpu_control_word();
static void set_fpu_control_word(int fpu_control);
static pthread_t main_thread(void) { return _main_thread; }
// returns kernel thread id (similar to LWP id on Solaris), which can be
// used to access /proc
static pid_t gettid();
static void set_createThread_lock(Mutex* lk) { _createThread_lock = lk; }
static Mutex* createThread_lock(void) { return _createThread_lock; }
static void hotspot_sigmask(Thread* thread);
static address initial_thread_stack_bottom(void) { return _initial_thread_stack_bottom; }
static uintptr_t initial_thread_stack_size(void) { return _initial_thread_stack_size; }
static bool is_initial_thread(void);
static int page_size(void) { return _page_size; }
static void set_page_size(int val) { _page_size = val; }
static address ucontext_get_pc(ucontext_t* uc);
static intptr_t* ucontext_get_sp(ucontext_t* uc);
static intptr_t* ucontext_get_fp(ucontext_t* uc);
// For Analyzer Forte AsyncGetCallTrace profiling support:
//
// This interface should be declared in os_linux_i486.hpp, but
// that file provides extensions to the os class and not the
// Linux class.
static ExtendedPC fetch_frame_from_ucontext(Thread* thread, ucontext_t* uc,
intptr_t** ret_sp, intptr_t** ret_fp);
// This boolean allows users to forward their own non-matching signals
// to JVM_handle_linux_signal, harmlessly.
static bool signal_handlers_are_installed;
static int get_our_sigflags(int);
static void set_our_sigflags(int, int);
static void signal_sets_init();
static void install_signal_handlers();
static void set_signal_handler(int, bool);
static bool is_sig_ignored(int sig);
static sigset_t* unblocked_signals();
static sigset_t* vm_signals();
static sigset_t* allowdebug_blocked_signals();
// For signal-chaining
static struct sigaction *get_chained_signal_action(int sig);
static bool chained_handler(int sig, siginfo_t* siginfo, void* context);
// GNU libc and libpthread version strings
static const char *glibc_version() { return _glibc_version; }
static const char *libpthread_version() { return _libpthread_version; }
// NPTL or LinuxThreads?
static bool is_LinuxThreads() { return !_is_NPTL; }
static bool is_NPTL() { return _is_NPTL; }
// NPTL is always floating stack. LinuxThreads could be using floating
// stack or fixed stack.
static bool is_floating_stack() { return _is_floating_stack; }
static void libpthread_init();
static bool libnuma_init();
static void* libnuma_dlsym(void* handle, const char* name);
// Minimum stack size a thread can be created with (allowing
// the VM to completely create the thread and enter user code)
static size_t min_stack_allowed;
// Return default stack size or guard size for the specified thread type
static size_t default_stack_size(os::ThreadType thr_type);
static size_t default_guard_size(os::ThreadType thr_type);
static void capture_initial_stack(size_t max_size);
// Stack overflow handling
static bool manually_expand_stack(JavaThread * t, address addr);
static int max_register_window_saves_before_flushing();
// Real-time clock functions
static void clock_init(void);
// fast POSIX clocks support
static void fast_thread_clock_init(void);
static bool supports_monotonic_clock() {
return _clock_gettime != NULL;
}
static int clock_gettime(clockid_t clock_id, struct timespec *tp) {
return _clock_gettime ? _clock_gettime(clock_id, tp) : -1;
}
static int pthread_getcpuclockid(pthread_t tid, clockid_t *clock_id) {
return _pthread_getcpuclockid ? _pthread_getcpuclockid(tid, clock_id) : -1;
}
static bool supports_fast_thread_cpu_time() {
return _supports_fast_thread_cpu_time;
}
static jlong fast_thread_cpu_time(clockid_t clockid);
// Stack repair handling
// none present
// LinuxThreads work-around for 6292965
static int safe_cond_timedwait(pthread_cond_t *_cond, pthread_mutex_t *_mutex, const struct timespec *_abstime);
// Linux suspend/resume support - this helper is a shadow of its former
// self now that low-level suspension is barely used, and old workarounds
// for LinuxThreads are no longer needed.
class SuspendResume {
private:
volatile int _suspend_action;
// values for suspend_action:
#define SR_NONE (0x00)
#define SR_SUSPEND (0x01) // suspend request
#define SR_CONTINUE (0x02) // resume request
volatile jint _state;
// values for _state: + SR_NONE
#define SR_SUSPENDED (0x20)
public:
SuspendResume() { _suspend_action = SR_NONE; _state = SR_NONE; }
int suspend_action() const { return _suspend_action; }
void set_suspend_action(int x) { _suspend_action = x; }
// atomic updates for _state
void set_suspended() {
jint temp, temp2;
do {
temp = _state;
temp2 = Atomic::cmpxchg(temp | SR_SUSPENDED, &_state, temp);
} while (temp2 != temp);
}
void clear_suspended() {
jint temp, temp2;
do {
temp = _state;
temp2 = Atomic::cmpxchg(temp & ~SR_SUSPENDED, &_state, temp);
} while (temp2 != temp);
}
bool is_suspended() { return _state & SR_SUSPENDED; }
#undef SR_SUSPENDED
};
private:
typedef int (*sched_getcpu_func_t)(void);
typedef int (*numa_node_to_cpus_func_t)(int node, unsigned long *buffer, int bufferlen);
typedef int (*numa_max_node_func_t)(void);
typedef int (*numa_available_func_t)(void);
typedef int (*numa_tonode_memory_func_t)(void *start, size_t size, int node);
typedef void (*numa_interleave_memory_func_t)(void *start, size_t size, unsigned long *nodemask);
static sched_getcpu_func_t _sched_getcpu;
static numa_node_to_cpus_func_t _numa_node_to_cpus;
static numa_max_node_func_t _numa_max_node;
static numa_available_func_t _numa_available;
static numa_tonode_memory_func_t _numa_tonode_memory;
static numa_interleave_memory_func_t _numa_interleave_memory;
static unsigned long* _numa_all_nodes;
static void set_sched_getcpu(sched_getcpu_func_t func) { _sched_getcpu = func; }
static void set_numa_node_to_cpus(numa_node_to_cpus_func_t func) { _numa_node_to_cpus = func; }
static void set_numa_max_node(numa_max_node_func_t func) { _numa_max_node = func; }
static void set_numa_available(numa_available_func_t func) { _numa_available = func; }
static void set_numa_tonode_memory(numa_tonode_memory_func_t func) { _numa_tonode_memory = func; }
static void set_numa_interleave_memory(numa_interleave_memory_func_t func) { _numa_interleave_memory = func; }
static void set_numa_all_nodes(unsigned long* ptr) { _numa_all_nodes = ptr; }
public:
static int sched_getcpu() { return _sched_getcpu != NULL ? _sched_getcpu() : -1; }
static int numa_node_to_cpus(int node, unsigned long *buffer, int bufferlen) {
return _numa_node_to_cpus != NULL ? _numa_node_to_cpus(node, buffer, bufferlen) : -1;
}
static int numa_max_node() { return _numa_max_node != NULL ? _numa_max_node() : -1; }
static int numa_available() { return _numa_available != NULL ? _numa_available() : -1; }
static int numa_tonode_memory(void *start, size_t size, int node) {
return _numa_tonode_memory != NULL ? _numa_tonode_memory(start, size, node) : -1;
}
static void numa_interleave_memory(void *start, size_t size) {
if (_numa_interleave_memory != NULL && _numa_all_nodes != NULL) {
_numa_interleave_memory(start, size, _numa_all_nodes);
}
}
static int get_node_by_cpu(int cpu_id);
};
class PlatformEvent : public CHeapObj {
private:
double CachePad [4] ; // increase odds that _mutex is sole occupant of cache line
volatile int _Event ;
volatile int _nParked ;
pthread_mutex_t _mutex [1] ;
pthread_cond_t _cond [1] ;
double PostPad [2] ;
Thread * _Assoc ;
public: // TODO-FIXME: make dtor private
~PlatformEvent() { guarantee (0, "invariant") ; }
public:
PlatformEvent() {
int status;
status = pthread_cond_init (_cond, NULL);
assert_status(status == 0, status, "cond_init");
status = pthread_mutex_init (_mutex, NULL);
assert_status(status == 0, status, "mutex_init");
_Event = 0 ;
_nParked = 0 ;
_Assoc = NULL ;
}
// Use caution with reset() and fired() -- they may require MEMBARs
void reset() { _Event = 0 ; }
int fired() { return _Event; }
void park () ;
void unpark () ;
int TryPark () ;
int park (jlong millis) ;
void SetAssociation (Thread * a) { _Assoc = a ; }
} ;
class PlatformParker : public CHeapObj {
protected:
pthread_mutex_t _mutex [1] ;
pthread_cond_t _cond [1] ;
public: // TODO-FIXME: make dtor private
~PlatformParker() { guarantee (0, "invariant") ; }
public:
PlatformParker() {
int status;
status = pthread_cond_init (_cond, NULL);
assert_status(status == 0, status, "cond_init");
status = pthread_mutex_init (_mutex, NULL);
assert_status(status == 0, status, "mutex_init");
}
} ;
#endif // OS_LINUX_VM_OS_LINUX_HPP