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src/os/bsd/vm/os_bsd.cpp
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@@ -160,11 +160,10 @@
////////////////////////////////////////////////////////////////////////////////
// utility functions
static int SR_initialize();
-static void unpackTime(timespec* absTime, bool isAbsolute, jlong time);
julong os::available_memory() {
return Bsd::available_memory();
}
@@ -531,11 +530,11 @@
////////////////////////////////////////////////////////////////////////////////
// signal support
debug_only(static bool signal_sets_initialized = false);
-static sigset_t unblocked_sigs, vm_sigs, allowdebug_blocked_sigs;
+static sigset_t unblocked_sigs, vm_sigs;
bool os::Bsd::is_sig_ignored(int sig) {
struct sigaction oact;
sigaction(sig, (struct sigaction*)NULL, &oact);
void* ohlr = oact.sa_sigaction ? CAST_FROM_FN_PTR(void*, oact.sa_sigaction)
@@ -562,29 +561,26 @@
// interference with shutdown hooks and BREAK_SIGNAL thread dumping.
// (See bug 4345157, and other related bugs).
// In reality, though, unblocking these signals is really a nop, since
// these signals are not blocked by default.
sigemptyset(&unblocked_sigs);
- sigemptyset(&allowdebug_blocked_sigs);
sigaddset(&unblocked_sigs, SIGILL);
sigaddset(&unblocked_sigs, SIGSEGV);
sigaddset(&unblocked_sigs, SIGBUS);
sigaddset(&unblocked_sigs, SIGFPE);
sigaddset(&unblocked_sigs, SR_signum);
if (!ReduceSignalUsage) {
if (!os::Bsd::is_sig_ignored(SHUTDOWN1_SIGNAL)) {
sigaddset(&unblocked_sigs, SHUTDOWN1_SIGNAL);
- sigaddset(&allowdebug_blocked_sigs, SHUTDOWN1_SIGNAL);
+
}
if (!os::Bsd::is_sig_ignored(SHUTDOWN2_SIGNAL)) {
sigaddset(&unblocked_sigs, SHUTDOWN2_SIGNAL);
- sigaddset(&allowdebug_blocked_sigs, SHUTDOWN2_SIGNAL);
}
if (!os::Bsd::is_sig_ignored(SHUTDOWN3_SIGNAL)) {
sigaddset(&unblocked_sigs, SHUTDOWN3_SIGNAL);
- sigaddset(&allowdebug_blocked_sigs, SHUTDOWN3_SIGNAL);
}
}
// Fill in signals that are blocked by all but the VM thread.
sigemptyset(&vm_sigs);
if (!ReduceSignalUsage) {
@@ -606,16 +602,10 @@
sigset_t* os::Bsd::vm_signals() {
assert(signal_sets_initialized, "Not initialized");
return &vm_sigs;
}
-// These are signals that are blocked during cond_wait to allow debugger in
-sigset_t* os::Bsd::allowdebug_blocked_signals() {
- assert(signal_sets_initialized, "Not initialized");
- return &allowdebug_blocked_sigs;
-}
-
void os::Bsd::hotspot_sigmask(Thread* thread) {
//Save caller's signal mask before setting VM signal mask
sigset_t caller_sigmask;
pthread_sigmask(SIG_BLOCK, NULL, &caller_sigmask);
@@ -3402,11 +3392,10 @@
char* format, ...);
// this is called _before_ the most of global arguments have been parsed
void os::init(void) {
char dummy; // used to get a guess on initial stack address
-// first_hrtime = gethrtime();
// With BsdThreads the JavaMain thread pid (primordial thread)
// is different than the pid of the java launcher thread.
// So, on Bsd, the launcher thread pid is passed to the VM
// via the sun.java.launcher.pid property.
@@ -3443,10 +3432,12 @@
// Linux, Solaris, and FreeBSD. On Mac OS X, dyld (rightly so) enforces
// alignment when doing symbol lookup. To work around this, we force early
// binding of all symbols now, thus binding when alignment is known-good.
_dyld_bind_fully_image_containing_address((const void *) &os::init);
#endif
+
+ os::Posix::init();
}
// To install functions for atexit system call
extern "C" {
static void perfMemory_exit_helper() {
@@ -3454,10 +3445,13 @@
}
}
// this is called _after_ the global arguments have been parsed
jint os::init_2(void) {
+
+ os::Posix::init_2();
+
// Allocate a single page and mark it as readable for safepoint polling
address polling_page = (address) ::mmap(NULL, Bsd::page_size(), PROT_READ, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
guarantee(polling_page != MAP_FAILED, "os::init_2: failed to allocate polling page");
os::set_polling_page(polling_page);
@@ -3521,11 +3515,11 @@
// note: perfMemory_exit_helper atexit function may be removed in
// the future if the appropriate cleanup code can be added to the
// VM_Exit VMOperation's doit method.
if (atexit(perfMemory_exit_helper) != 0) {
- warning("os::init2 atexit(perfMemory_exit_helper) failed");
+ warning("os::init_2 atexit(perfMemory_exit_helper) failed");
}
}
// initialize thread priority policy
prio_init();
@@ -4026,369 +4020,10 @@
jio_fprintf(stderr,
"Could not open pause file '%s', continuing immediately.\n", filename);
}
}
-
-// Refer to the comments in os_solaris.cpp park-unpark. The next two
-// comment paragraphs are worth repeating here:
-//
-// Assumption:
-// Only one parker can exist on an event, which is why we allocate
-// them per-thread. Multiple unparkers can coexist.
-//
-// _Event serves as a restricted-range semaphore.
-// -1 : thread is blocked, i.e. there is a waiter
-// 0 : neutral: thread is running or ready,
-// could have been signaled after a wait started
-// 1 : signaled - thread is running or ready
-//
-
-// utility to compute the abstime argument to timedwait:
-// millis is the relative timeout time
-// abstime will be the absolute timeout time
-// TODO: replace compute_abstime() with unpackTime()
-
-static struct timespec* compute_abstime(struct timespec* abstime,
- jlong millis) {
- if (millis < 0) millis = 0;
- struct timeval now;
- int status = gettimeofday(&now, NULL);
- assert(status == 0, "gettimeofday");
- jlong seconds = millis / 1000;
- millis %= 1000;
- if (seconds > 50000000) { // see man cond_timedwait(3T)
- seconds = 50000000;
- }
- abstime->tv_sec = now.tv_sec + seconds;
- long usec = now.tv_usec + millis * 1000;
- if (usec >= 1000000) {
- abstime->tv_sec += 1;
- usec -= 1000000;
- }
- abstime->tv_nsec = usec * 1000;
- return abstime;
-}
-
-void os::PlatformEvent::park() { // AKA "down()"
- // Transitions for _Event:
- // -1 => -1 : illegal
- // 1 => 0 : pass - return immediately
- // 0 => -1 : block; then set _Event to 0 before returning
-
- // Invariant: Only the thread associated with the Event/PlatformEvent
- // may call park().
- // TODO: assert that _Assoc != NULL or _Assoc == Self
- assert(_nParked == 0, "invariant");
-
- int v;
- for (;;) {
- v = _Event;
- if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
- }
- guarantee(v >= 0, "invariant");
- if (v == 0) {
- // Do this the hard way by blocking ...
- int status = pthread_mutex_lock(_mutex);
- assert_status(status == 0, status, "mutex_lock");
- guarantee(_nParked == 0, "invariant");
- ++_nParked;
- while (_Event < 0) {
- status = pthread_cond_wait(_cond, _mutex);
- // for some reason, under 2.7 lwp_cond_wait() may return ETIME ...
- // Treat this the same as if the wait was interrupted
- if (status == ETIMEDOUT) { status = EINTR; }
- assert_status(status == 0 || status == EINTR, status, "cond_wait");
- }
- --_nParked;
-
- _Event = 0;
- status = pthread_mutex_unlock(_mutex);
- assert_status(status == 0, status, "mutex_unlock");
- // Paranoia to ensure our locked and lock-free paths interact
- // correctly with each other.
- OrderAccess::fence();
- }
- guarantee(_Event >= 0, "invariant");
-}
-
-int os::PlatformEvent::park(jlong millis) {
- // Transitions for _Event:
- // -1 => -1 : illegal
- // 1 => 0 : pass - return immediately
- // 0 => -1 : block; then set _Event to 0 before returning
-
- guarantee(_nParked == 0, "invariant");
-
- int v;
- for (;;) {
- v = _Event;
- if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
- }
- guarantee(v >= 0, "invariant");
- if (v != 0) return OS_OK;
-
- // We do this the hard way, by blocking the thread.
- // Consider enforcing a minimum timeout value.
- struct timespec abst;
- compute_abstime(&abst, millis);
-
- int ret = OS_TIMEOUT;
- int status = pthread_mutex_lock(_mutex);
- assert_status(status == 0, status, "mutex_lock");
- guarantee(_nParked == 0, "invariant");
- ++_nParked;
-
- // Object.wait(timo) will return because of
- // (a) notification
- // (b) timeout
- // (c) thread.interrupt
- //
- // Thread.interrupt and object.notify{All} both call Event::set.
- // That is, we treat thread.interrupt as a special case of notification.
- // We ignore spurious OS wakeups unless FilterSpuriousWakeups is false.
- // We assume all ETIME returns are valid.
- //
- // TODO: properly differentiate simultaneous notify+interrupt.
- // In that case, we should propagate the notify to another waiter.
-
- while (_Event < 0) {
- status = pthread_cond_timedwait(_cond, _mutex, &abst);
- assert_status(status == 0 || status == EINTR ||
- status == ETIMEDOUT,
- status, "cond_timedwait");
- if (!FilterSpuriousWakeups) break; // previous semantics
- if (status == ETIMEDOUT) break;
- // We consume and ignore EINTR and spurious wakeups.
- }
- --_nParked;
- if (_Event >= 0) {
- ret = OS_OK;
- }
- _Event = 0;
- status = pthread_mutex_unlock(_mutex);
- assert_status(status == 0, status, "mutex_unlock");
- assert(_nParked == 0, "invariant");
- // Paranoia to ensure our locked and lock-free paths interact
- // correctly with each other.
- OrderAccess::fence();
- return ret;
-}
-
-void os::PlatformEvent::unpark() {
- // Transitions for _Event:
- // 0 => 1 : just return
- // 1 => 1 : just return
- // -1 => either 0 or 1; must signal target thread
- // That is, we can safely transition _Event from -1 to either
- // 0 or 1.
- // See also: "Semaphores in Plan 9" by Mullender & Cox
- //
- // Note: Forcing a transition from "-1" to "1" on an unpark() means
- // that it will take two back-to-back park() calls for the owning
- // thread to block. This has the benefit of forcing a spurious return
- // from the first park() call after an unpark() call which will help
- // shake out uses of park() and unpark() without condition variables.
-
- if (Atomic::xchg(1, &_Event) >= 0) return;
-
- // Wait for the thread associated with the event to vacate
- int status = pthread_mutex_lock(_mutex);
- assert_status(status == 0, status, "mutex_lock");
- int AnyWaiters = _nParked;
- assert(AnyWaiters == 0 || AnyWaiters == 1, "invariant");
- status = pthread_mutex_unlock(_mutex);
- assert_status(status == 0, status, "mutex_unlock");
- if (AnyWaiters != 0) {
- // Note that we signal() *after* dropping the lock for "immortal" Events.
- // This is safe and avoids a common class of futile wakeups. In rare
- // circumstances this can cause a thread to return prematurely from
- // cond_{timed}wait() but the spurious wakeup is benign and the victim
- // will simply re-test the condition and re-park itself.
- // This provides particular benefit if the underlying platform does not
- // provide wait morphing.
- status = pthread_cond_signal(_cond);
- assert_status(status == 0, status, "cond_signal");
- }
-}
-
-
-// JSR166
-// -------------------------------------------------------
-
-// The solaris and bsd implementations of park/unpark are fairly
-// conservative for now, but can be improved. They currently use a
-// mutex/condvar pair, plus a a count.
-// Park decrements count if > 0, else does a condvar wait. Unpark
-// sets count to 1 and signals condvar. Only one thread ever waits
-// on the condvar. Contention seen when trying to park implies that someone
-// is unparking you, so don't wait. And spurious returns are fine, so there
-// is no need to track notifications.
-
-#define MAX_SECS 100000000
-
-// This code is common to bsd and solaris and will be moved to a
-// common place in dolphin.
-//
-// The passed in time value is either a relative time in nanoseconds
-// or an absolute time in milliseconds. Either way it has to be unpacked
-// into suitable seconds and nanoseconds components and stored in the
-// given timespec structure.
-// Given time is a 64-bit value and the time_t used in the timespec is only
-// a signed-32-bit value (except on 64-bit Bsd) we have to watch for
-// overflow if times way in the future are given. Further on Solaris versions
-// prior to 10 there is a restriction (see cond_timedwait) that the specified
-// number of seconds, in abstime, is less than current_time + 100,000,000.
-// As it will be 28 years before "now + 100000000" will overflow we can
-// ignore overflow and just impose a hard-limit on seconds using the value
-// of "now + 100,000,000". This places a limit on the timeout of about 3.17
-// years from "now".
-
-static void unpackTime(struct timespec* absTime, bool isAbsolute, jlong time) {
- assert(time > 0, "convertTime");
-
- struct timeval now;
- int status = gettimeofday(&now, NULL);
- assert(status == 0, "gettimeofday");
-
- time_t max_secs = now.tv_sec + MAX_SECS;
-
- if (isAbsolute) {
- jlong secs = time / 1000;
- if (secs > max_secs) {
- absTime->tv_sec = max_secs;
- } else {
- absTime->tv_sec = secs;
- }
- absTime->tv_nsec = (time % 1000) * NANOSECS_PER_MILLISEC;
- } else {
- jlong secs = time / NANOSECS_PER_SEC;
- if (secs >= MAX_SECS) {
- absTime->tv_sec = max_secs;
- absTime->tv_nsec = 0;
- } else {
- absTime->tv_sec = now.tv_sec + secs;
- absTime->tv_nsec = (time % NANOSECS_PER_SEC) + now.tv_usec*1000;
- if (absTime->tv_nsec >= NANOSECS_PER_SEC) {
- absTime->tv_nsec -= NANOSECS_PER_SEC;
- ++absTime->tv_sec; // note: this must be <= max_secs
- }
- }
- }
- assert(absTime->tv_sec >= 0, "tv_sec < 0");
- assert(absTime->tv_sec <= max_secs, "tv_sec > max_secs");
- assert(absTime->tv_nsec >= 0, "tv_nsec < 0");
- assert(absTime->tv_nsec < NANOSECS_PER_SEC, "tv_nsec >= nanos_per_sec");
-}
-
-void Parker::park(bool isAbsolute, jlong time) {
- // Ideally we'd do something useful while spinning, such
- // as calling unpackTime().
-
- // Optional fast-path check:
- // Return immediately if a permit is available.
- // We depend on Atomic::xchg() having full barrier semantics
- // since we are doing a lock-free update to _counter.
- if (Atomic::xchg(0, &_counter) > 0) return;
-
- Thread* thread = Thread::current();
- assert(thread->is_Java_thread(), "Must be JavaThread");
- JavaThread *jt = (JavaThread *)thread;
-
- // Optional optimization -- avoid state transitions if there's an interrupt pending.
- // Check interrupt before trying to wait
- if (Thread::is_interrupted(thread, false)) {
- return;
- }
-
- // Next, demultiplex/decode time arguments
- struct timespec absTime;
- if (time < 0 || (isAbsolute && time == 0)) { // don't wait at all
- return;
- }
- if (time > 0) {
- unpackTime(&absTime, isAbsolute, time);
- }
-
-
- // Enter safepoint region
- // Beware of deadlocks such as 6317397.
- // The per-thread Parker:: mutex is a classic leaf-lock.
- // In particular a thread must never block on the Threads_lock while
- // holding the Parker:: mutex. If safepoints are pending both the
- // the ThreadBlockInVM() CTOR and DTOR may grab Threads_lock.
- ThreadBlockInVM tbivm(jt);
-
- // Don't wait if cannot get lock since interference arises from
- // unblocking. Also. check interrupt before trying wait
- if (Thread::is_interrupted(thread, false) || pthread_mutex_trylock(_mutex) != 0) {
- return;
- }
-
- int status;
- if (_counter > 0) { // no wait needed
- _counter = 0;
- status = pthread_mutex_unlock(_mutex);
- assert_status(status == 0, status, "invariant");
- // Paranoia to ensure our locked and lock-free paths interact
- // correctly with each other and Java-level accesses.
- OrderAccess::fence();
- return;
- }
-
-#ifdef ASSERT
- // Don't catch signals while blocked; let the running threads have the signals.
- // (This allows a debugger to break into the running thread.)
- sigset_t oldsigs;
- sigset_t* allowdebug_blocked = os::Bsd::allowdebug_blocked_signals();
- pthread_sigmask(SIG_BLOCK, allowdebug_blocked, &oldsigs);
-#endif
-
- OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
- jt->set_suspend_equivalent();
- // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
-
- if (time == 0) {
- status = pthread_cond_wait(_cond, _mutex);
- } else {
- status = pthread_cond_timedwait(_cond, _mutex, &absTime);
- }
- assert_status(status == 0 || status == EINTR ||
- status == ETIMEDOUT,
- status, "cond_timedwait");
-
-#ifdef ASSERT
- pthread_sigmask(SIG_SETMASK, &oldsigs, NULL);
-#endif
-
- _counter = 0;
- status = pthread_mutex_unlock(_mutex);
- assert_status(status == 0, status, "invariant");
- // Paranoia to ensure our locked and lock-free paths interact
- // correctly with each other and Java-level accesses.
- OrderAccess::fence();
-
- // If externally suspended while waiting, re-suspend
- if (jt->handle_special_suspend_equivalent_condition()) {
- jt->java_suspend_self();
- }
-}
-
-void Parker::unpark() {
- int status = pthread_mutex_lock(_mutex);
- assert_status(status == 0, status, "invariant");
- const int s = _counter;
- _counter = 1;
- status = pthread_mutex_unlock(_mutex);
- assert_status(status == 0, status, "invariant");
- if (s < 1) {
- status = pthread_cond_signal(_cond);
- assert_status(status == 0, status, "invariant");
- }
-}
-
-
// Darwin has no "environ" in a dynamic library.
#ifdef __APPLE__
#include <crt_externs.h>
#define environ (*_NSGetEnviron())
#else
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