6944584: Improvements to subprocess handling on Unix
Summary: use thread pool for reaper thread; move most I/O operations out of reaper thread
Reviewed-by: michaelm, hiroshi
/*
* Copyright 1999-2009 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*
*/
// do not include precompiled header file
# include <signal.h> // needed first to avoid name collision for "std" with SC 5.0
# include "incls/_os_solaris_sparc.cpp.incl"
// put OS-includes here
# include <sys/types.h>
# include <sys/mman.h>
# include <pthread.h>
# include <errno.h>
# include <dlfcn.h>
# include <stdio.h>
# include <unistd.h>
# include <sys/resource.h>
# include <thread.h>
# include <sys/stat.h>
# include <sys/time.h>
# include <sys/filio.h>
# include <sys/utsname.h>
# include <sys/systeminfo.h>
# include <sys/socket.h>
# include <sys/lwp.h>
# include <pwd.h>
# include <poll.h>
# include <sys/lwp.h>
# define _STRUCTURED_PROC 1 // this gets us the new structured proc interfaces of 5.6 & later
# include <sys/procfs.h> // see comment in <sys/procfs.h>
#define MAX_PATH (2 * K)
// Minimum stack size for the VM. It's easier to document a constant
// but it's different for x86 and sparc because the page sizes are different.
#ifdef _LP64
size_t os::Solaris::min_stack_allowed = 128*K;
#else
size_t os::Solaris::min_stack_allowed = 96*K;
#endif
int os::Solaris::max_register_window_saves_before_flushing() {
// We should detect this at run time. For now, filling
// in with a constant.
return 8;
}
static void handle_unflushed_register_windows(gwindows_t *win) {
int restore_count = win->wbcnt;
int i;
for(i=0; i<restore_count; i++) {
address sp = ((address)win->spbuf[i]) + STACK_BIAS;
address reg_win = (address)&win->wbuf[i];
memcpy(sp,reg_win,sizeof(struct rwindow));
}
}
char* os::non_memory_address_word() {
// Must never look like an address returned by reserve_memory,
// even in its subfields (as defined by the CPU immediate fields,
// if the CPU splits constants across multiple instructions).
// On SPARC, 0 != %hi(any real address), because there is no
// allocation in the first 1Kb of the virtual address space.
return (char*) 0;
}
// Validate a ucontext retrieved from walking a uc_link of a ucontext.
// There are issues with libthread giving out uc_links for different threads
// on the same uc_link chain and bad or circular links.
//
bool os::Solaris::valid_ucontext(Thread* thread, ucontext_t* valid, ucontext_t* suspect) {
if (valid >= suspect ||
valid->uc_stack.ss_flags != suspect->uc_stack.ss_flags ||
valid->uc_stack.ss_sp != suspect->uc_stack.ss_sp ||
valid->uc_stack.ss_size != suspect->uc_stack.ss_size) {
DEBUG_ONLY(tty->print_cr("valid_ucontext: failed test 1");)
return false;
}
if (thread->is_Java_thread()) {
if (!valid_stack_address(thread, (address)suspect)) {
DEBUG_ONLY(tty->print_cr("valid_ucontext: uc_link not in thread stack");)
return false;
}
address _sp = (address)((intptr_t)suspect->uc_mcontext.gregs[REG_SP] + STACK_BIAS);
if (!valid_stack_address(thread, _sp) ||
!frame::is_valid_stack_pointer(((JavaThread*)thread)->base_of_stack_pointer(), (intptr_t*)_sp)) {
DEBUG_ONLY(tty->print_cr("valid_ucontext: stackpointer not in thread stack");)
return false;
}
}
return true;
}
// We will only follow one level of uc_link since there are libthread
// issues with ucontext linking and it is better to be safe and just
// let caller retry later.
ucontext_t* os::Solaris::get_valid_uc_in_signal_handler(Thread *thread,
ucontext_t *uc) {
ucontext_t *retuc = NULL;
// Sometimes the topmost register windows are not properly flushed.
// i.e., if the kernel would have needed to take a page fault
if (uc != NULL && uc->uc_mcontext.gwins != NULL) {
::handle_unflushed_register_windows(uc->uc_mcontext.gwins);
}
if (uc != NULL) {
if (uc->uc_link == NULL) {
// cannot validate without uc_link so accept current ucontext
retuc = uc;
} else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
// first ucontext is valid so try the next one
uc = uc->uc_link;
if (uc->uc_link == NULL) {
// cannot validate without uc_link so accept current ucontext
retuc = uc;
} else if (os::Solaris::valid_ucontext(thread, uc, uc->uc_link)) {
// the ucontext one level down is also valid so return it
retuc = uc;
}
}
}
return retuc;
}
// Assumes ucontext is valid
ExtendedPC os::Solaris::ucontext_get_ExtendedPC(ucontext_t *uc) {
address pc = (address)uc->uc_mcontext.gregs[REG_PC];
// set npc to zero to avoid using it for safepoint, good for profiling only
return ExtendedPC(pc);
}
// Assumes ucontext is valid
intptr_t* os::Solaris::ucontext_get_sp(ucontext_t *uc) {
return (intptr_t*)((intptr_t)uc->uc_mcontext.gregs[REG_SP] + STACK_BIAS);
}
// Solaris X86 only
intptr_t* os::Solaris::ucontext_get_fp(ucontext_t *uc) {
ShouldNotReachHere();
return NULL;
}
// For Forte Analyzer AsyncGetCallTrace profiling support - thread
// is currently interrupted by SIGPROF.
//
// ret_fp parameter is only used by Solaris X86.
//
// The difference between this and os::fetch_frame_from_context() is that
// here we try to skip nested signal frames.
ExtendedPC os::Solaris::fetch_frame_from_ucontext(Thread* thread,
ucontext_t* uc, intptr_t** ret_sp, intptr_t** ret_fp) {
assert(thread != NULL, "just checking");
assert(ret_sp != NULL, "just checking");
assert(ret_fp == NULL, "just checking");
ucontext_t *luc = os::Solaris::get_valid_uc_in_signal_handler(thread, uc);
return os::fetch_frame_from_context(luc, ret_sp, ret_fp);
}
// ret_fp parameter is only used by Solaris X86.
ExtendedPC os::fetch_frame_from_context(void* ucVoid,
intptr_t** ret_sp, intptr_t** ret_fp) {
ExtendedPC epc;
ucontext_t *uc = (ucontext_t*)ucVoid;
if (uc != NULL) {
epc = os::Solaris::ucontext_get_ExtendedPC(uc);
if (ret_sp) *ret_sp = os::Solaris::ucontext_get_sp(uc);
} else {
// construct empty ExtendedPC for return value checking
epc = ExtendedPC(NULL);
if (ret_sp) *ret_sp = (intptr_t *)NULL;
}
return epc;
}
frame os::fetch_frame_from_context(void* ucVoid) {
intptr_t* sp;
intptr_t* fp;
ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, &fp);
return frame(sp, frame::unpatchable, epc.pc());
}
frame os::get_sender_for_C_frame(frame* fr) {
return frame(fr->sender_sp(), frame::unpatchable, fr->sender_pc());
}
frame os::current_frame() {
intptr_t* sp = StubRoutines::Sparc::flush_callers_register_windows_func()();
frame myframe(sp, frame::unpatchable,
CAST_FROM_FN_PTR(address, os::current_frame));
if (os::is_first_C_frame(&myframe)) {
// stack is not walkable
return frame(NULL, NULL, NULL);
} else {
return os::get_sender_for_C_frame(&myframe);
}
}
void GetThreadPC_Callback::execute(OSThread::InterruptArguments *args) {
Thread* thread = args->thread();
ucontext_t* uc = args->ucontext();
intptr_t* sp;
assert(ProfileVM && thread->is_VM_thread(), "just checking");
// Skip the mcontext corruption verification. If if occasionally
// things get corrupt, it is ok for profiling - we will just get an unresolved
// function name
ExtendedPC new_addr((address)uc->uc_mcontext.gregs[REG_PC]);
_addr = new_addr;
}
static int threadgetstate(thread_t tid, int *flags, lwpid_t *lwp, stack_t *ss, gregset_t rs, lwpstatus_t *lwpstatus) {
char lwpstatusfile[PROCFILE_LENGTH];
int lwpfd, err;
if (err = os::Solaris::thr_getstate(tid, flags, lwp, ss, rs))
return (err);
if (*flags == TRS_LWPID) {
sprintf(lwpstatusfile, "/proc/%d/lwp/%d/lwpstatus", getpid(),
*lwp);
if ((lwpfd = open(lwpstatusfile, O_RDONLY)) < 0) {
perror("thr_mutator_status: open lwpstatus");
return (EINVAL);
}
if (pread(lwpfd, lwpstatus, sizeof (lwpstatus_t), (off_t)0) !=
sizeof (lwpstatus_t)) {
perror("thr_mutator_status: read lwpstatus");
(void) close(lwpfd);
return (EINVAL);
}
(void) close(lwpfd);
}
return (0);
}
bool os::is_allocatable(size_t bytes) {
#ifdef _LP64
return true;
#else
return (bytes <= (size_t)3835*M);
#endif
}
extern "C" void Fetch32PFI () ;
extern "C" void Fetch32Resume () ;
extern "C" void FetchNPFI () ;
extern "C" void FetchNResume () ;
extern "C" int JVM_handle_solaris_signal(int signo, siginfo_t* siginfo, void* ucontext, int abort_if_unrecognized);
int JVM_handle_solaris_signal(int sig, siginfo_t* info, void* ucVoid, int abort_if_unrecognized) {
ucontext_t* uc = (ucontext_t*) ucVoid;
Thread* t = ThreadLocalStorage::get_thread_slow();
SignalHandlerMark shm(t);
if(sig == SIGPIPE || sig == SIGXFSZ) {
if (os::Solaris::chained_handler(sig, info, ucVoid)) {
return true;
} else {
if (PrintMiscellaneous && (WizardMode || Verbose)) {
char buf[64];
warning("Ignoring %s - see 4229104 or 6499219",
os::exception_name(sig, buf, sizeof(buf)));
}
return true;
}
}
JavaThread* thread = NULL;
VMThread* vmthread = NULL;
if (os::Solaris::signal_handlers_are_installed) {
if (t != NULL ){
if(t->is_Java_thread()) {
thread = (JavaThread*)t;
}
else if(t->is_VM_thread()){
vmthread = (VMThread *)t;
}
}
}
guarantee(sig != os::Solaris::SIGinterrupt(), "Can not chain VM interrupt signal, try -XX:+UseAltSigs");
if (sig == os::Solaris::SIGasync()) {
if (thread) {
OSThread::InterruptArguments args(thread, uc);
thread->osthread()->do_interrupt_callbacks_at_interrupt(&args);
return true;
} else if (vmthread) {
OSThread::InterruptArguments args(vmthread, uc);
vmthread->osthread()->do_interrupt_callbacks_at_interrupt(&args);
return true;
} else if (os::Solaris::chained_handler(sig, info, ucVoid)) {
return true;
} else {
// If os::Solaris::SIGasync not chained, and this is a non-vm and
// non-java thread
return true;
}
}
if (info == NULL || info->si_code <= 0 || info->si_code == SI_NOINFO) {
// can't decode this kind of signal
info = NULL;
} else {
assert(sig == info->si_signo, "bad siginfo");
}
// decide if this trap can be handled by a stub
address stub = NULL;
address pc = NULL;
address npc = NULL;
//%note os_trap_1
if (info != NULL && uc != NULL && thread != NULL) {
// factor me: getPCfromContext
pc = (address) uc->uc_mcontext.gregs[REG_PC];
npc = (address) uc->uc_mcontext.gregs[REG_nPC];
// SafeFetch() support
// Implemented with either a fixed set of addresses such
// as Fetch32*, or with Thread._OnTrap.
if (uc->uc_mcontext.gregs[REG_PC] == intptr_t(Fetch32PFI)) {
uc->uc_mcontext.gregs [REG_PC] = intptr_t(Fetch32Resume) ;
uc->uc_mcontext.gregs [REG_nPC] = intptr_t(Fetch32Resume) + 4 ;
return true ;
}
if (uc->uc_mcontext.gregs[REG_PC] == intptr_t(FetchNPFI)) {
uc->uc_mcontext.gregs [REG_PC] = intptr_t(FetchNResume) ;
uc->uc_mcontext.gregs [REG_nPC] = intptr_t(FetchNResume) + 4 ;
return true ;
}
// Handle ALL stack overflow variations here
if (sig == SIGSEGV && info->si_code == SEGV_ACCERR) {
address addr = (address) info->si_addr;
if (thread->in_stack_yellow_zone(addr)) {
thread->disable_stack_yellow_zone();
// Sometimes the register windows are not properly flushed.
if(uc->uc_mcontext.gwins != NULL) {
::handle_unflushed_register_windows(uc->uc_mcontext.gwins);
}
if (thread->thread_state() == _thread_in_Java) {
// Throw a stack overflow exception. Guard pages will be reenabled
// while unwinding the stack.
stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW);
} else {
// Thread was in the vm or native code. Return and try to finish.
return true;
}
} else if (thread->in_stack_red_zone(addr)) {
// Fatal red zone violation. Disable the guard pages and fall through
// to handle_unexpected_exception way down below.
thread->disable_stack_red_zone();
tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
// Sometimes the register windows are not properly flushed.
if(uc->uc_mcontext.gwins != NULL) {
::handle_unflushed_register_windows(uc->uc_mcontext.gwins);
}
}
}
if (thread->thread_state() == _thread_in_vm) {
if (sig == SIGBUS && info->si_code == BUS_OBJERR && thread->doing_unsafe_access()) {
stub = StubRoutines::handler_for_unsafe_access();
}
}
else if (thread->thread_state() == _thread_in_Java) {
// Java thread running in Java code => find exception handler if any
// a fault inside compiled code, the interpreter, or a stub
// Support Safepoint Polling
if ( sig == SIGSEGV && (address)info->si_addr == os::get_polling_page() ) {
stub = SharedRuntime::get_poll_stub(pc);
}
// Not needed on x86 solaris because verify_oops doesn't generate
// SEGV/BUS like sparc does.
if ( (sig == SIGSEGV || sig == SIGBUS)
&& pc >= MacroAssembler::_verify_oop_implicit_branch[0]
&& pc < MacroAssembler::_verify_oop_implicit_branch[1] ) {
stub = MacroAssembler::_verify_oop_implicit_branch[2];
warning("fixed up memory fault in +VerifyOops at address " INTPTR_FORMAT, info->si_addr);
}
// This is not factored because on x86 solaris the patching for
// zombies does not generate a SEGV.
else if (sig == SIGSEGV && nativeInstruction_at(pc)->is_zombie()) {
// zombie method (ld [%g0],%o7 instruction)
stub = SharedRuntime::get_handle_wrong_method_stub();
// At the stub it needs to look like a call from the caller of this
// method (not a call from the segv site).
pc = (address)uc->uc_mcontext.gregs[REG_O7];
}
else if (sig == SIGBUS && info->si_code == BUS_OBJERR) {
// BugId 4454115: A read from a MappedByteBuffer can fault
// here if the underlying file has been truncated.
// Do not crash the VM in such a case.
CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
if (nm != NULL && nm->has_unsafe_access()) {
stub = StubRoutines::handler_for_unsafe_access();
}
}
else if (sig == SIGFPE && info->si_code == FPE_INTDIV) {
// integer divide by zero
stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
}
else if (sig == SIGFPE && info->si_code == FPE_FLTDIV) {
// floating-point divide by zero
stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
}
#ifdef COMPILER2
else if (sig == SIGILL && nativeInstruction_at(pc)->is_ic_miss_trap()) {
#ifdef ASSERT
#ifdef TIERED
CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
assert(cb->is_compiled_by_c2(), "Wrong compiler");
#endif // TIERED
#endif // ASSERT
// Inline cache missed and user trap "Tne G0+ST_RESERVED_FOR_USER_0+2" taken.
stub = SharedRuntime::get_ic_miss_stub();
// At the stub it needs to look like a call from the caller of this
// method (not a call from the segv site).
pc = (address)uc->uc_mcontext.gregs[REG_O7];
}
#endif // COMPILER2
else if (sig == SIGSEGV && info->si_code > 0 && !MacroAssembler::needs_explicit_null_check((intptr_t)info->si_addr)) {
// Determination of interpreter/vtable stub/compiled code null exception
stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
}
}
// jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
// and the heap gets shrunk before the field access.
if ((sig == SIGSEGV) || (sig == SIGBUS)) {
address addr = JNI_FastGetField::find_slowcase_pc(pc);
if (addr != (address)-1) {
stub = addr;
}
}
// Check to see if we caught the safepoint code in the
// process of write protecting the memory serialization page.
// It write enables the page immediately after protecting it
// so just return.
if ((sig == SIGSEGV) &&
os::is_memory_serialize_page(thread, (address)info->si_addr)) {
// Block current thread until the memory serialize page permission restored.
os::block_on_serialize_page_trap();
return true;
}
}
if (stub != NULL) {
// save all thread context in case we need to restore it
thread->set_saved_exception_pc(pc);
thread->set_saved_exception_npc(npc);
// simulate a branch to the stub (a "call" in the safepoint stub case)
// factor me: setPC
uc->uc_mcontext.gregs[REG_PC ] = (greg_t)stub;
uc->uc_mcontext.gregs[REG_nPC] = (greg_t)(stub + 4);
#ifndef PRODUCT
if (TraceJumps) thread->record_jump(stub, NULL, __FILE__, __LINE__);
#endif /* PRODUCT */
return true;
}
// signal-chaining
if (os::Solaris::chained_handler(sig, info, ucVoid)) {
return true;
}
if (!abort_if_unrecognized) {
// caller wants another chance, so give it to him
return false;
}
if (!os::Solaris::libjsig_is_loaded) {
struct sigaction oldAct;
sigaction(sig, (struct sigaction *)0, &oldAct);
if (oldAct.sa_sigaction != signalHandler) {
void* sighand = oldAct.sa_sigaction ? CAST_FROM_FN_PTR(void*, oldAct.sa_sigaction)
: CAST_FROM_FN_PTR(void*, oldAct.sa_handler);
warning("Unexpected Signal %d occurred under user-defined signal handler " INTPTR_FORMAT, sig, (intptr_t)sighand);
}
}
if (pc == NULL && uc != NULL) {
pc = (address) uc->uc_mcontext.gregs[REG_PC];
}
// unmask current signal
sigset_t newset;
sigemptyset(&newset);
sigaddset(&newset, sig);
sigprocmask(SIG_UNBLOCK, &newset, NULL);
VMError err(t, sig, pc, info, ucVoid);
err.report_and_die();
ShouldNotReachHere();
}
void os::print_context(outputStream *st, void *context) {
if (context == NULL) return;
ucontext_t *uc = (ucontext_t*)context;
st->print_cr("Registers:");
st->print_cr(" O0=" INTPTR_FORMAT " O1=" INTPTR_FORMAT
" O2=" INTPTR_FORMAT " O3=" INTPTR_FORMAT,
uc->uc_mcontext.gregs[REG_O0],
uc->uc_mcontext.gregs[REG_O1],
uc->uc_mcontext.gregs[REG_O2],
uc->uc_mcontext.gregs[REG_O3]);
st->print_cr(" O4=" INTPTR_FORMAT " O5=" INTPTR_FORMAT
" O6=" INTPTR_FORMAT " O7=" INTPTR_FORMAT,
uc->uc_mcontext.gregs[REG_O4],
uc->uc_mcontext.gregs[REG_O5],
uc->uc_mcontext.gregs[REG_O6],
uc->uc_mcontext.gregs[REG_O7]);
st->print_cr(" G1=" INTPTR_FORMAT " G2=" INTPTR_FORMAT
" G3=" INTPTR_FORMAT " G4=" INTPTR_FORMAT,
uc->uc_mcontext.gregs[REG_G1],
uc->uc_mcontext.gregs[REG_G2],
uc->uc_mcontext.gregs[REG_G3],
uc->uc_mcontext.gregs[REG_G4]);
st->print_cr(" G5=" INTPTR_FORMAT " G6=" INTPTR_FORMAT
" G7=" INTPTR_FORMAT " Y=" INTPTR_FORMAT,
uc->uc_mcontext.gregs[REG_G5],
uc->uc_mcontext.gregs[REG_G6],
uc->uc_mcontext.gregs[REG_G7],
uc->uc_mcontext.gregs[REG_Y]);
st->print_cr(" PC=" INTPTR_FORMAT " nPC=" INTPTR_FORMAT,
uc->uc_mcontext.gregs[REG_PC],
uc->uc_mcontext.gregs[REG_nPC]);
st->cr();
st->cr();
intptr_t *sp = (intptr_t *)os::Solaris::ucontext_get_sp(uc);
st->print_cr("Top of Stack: (sp=" PTR_FORMAT ")", sp);
print_hex_dump(st, (address)sp, (address)(sp + 32), sizeof(intptr_t));
st->cr();
// Note: it may be unsafe to inspect memory near pc. For example, pc may
// point to garbage if entry point in an nmethod is corrupted. Leave
// this at the end, and hope for the best.
ExtendedPC epc = os::Solaris::ucontext_get_ExtendedPC(uc);
address pc = epc.pc();
st->print_cr("Instructions: (pc=" PTR_FORMAT ")", pc);
print_hex_dump(st, pc - 16, pc + 16, sizeof(char));
}
void os::Solaris::init_thread_fpu_state(void) {
// Nothing needed on Sparc.
}
#if !defined(COMPILER2) && !defined(_LP64)
// These routines are the initial value of atomic_xchg_entry(),
// atomic_cmpxchg_entry(), atomic_add_entry() and fence_entry()
// until initialization is complete.
// TODO - remove when the VM drops support for V8.
typedef jint xchg_func_t (jint, volatile jint*);
typedef jint cmpxchg_func_t (jint, volatile jint*, jint);
typedef jlong cmpxchg_long_func_t(jlong, volatile jlong*, jlong);
typedef jint add_func_t (jint, volatile jint*);
jint os::atomic_xchg_bootstrap(jint exchange_value, volatile jint* dest) {
// try to use the stub:
xchg_func_t* func = CAST_TO_FN_PTR(xchg_func_t*, StubRoutines::atomic_xchg_entry());
if (func != NULL) {
os::atomic_xchg_func = func;
return (*func)(exchange_value, dest);
}
assert(Threads::number_of_threads() == 0, "for bootstrap only");
jint old_value = *dest;
*dest = exchange_value;
return old_value;
}
jint os::atomic_cmpxchg_bootstrap(jint exchange_value, volatile jint* dest, jint compare_value) {
// try to use the stub:
cmpxchg_func_t* func = CAST_TO_FN_PTR(cmpxchg_func_t*, StubRoutines::atomic_cmpxchg_entry());
if (func != NULL) {
os::atomic_cmpxchg_func = func;
return (*func)(exchange_value, dest, compare_value);
}
assert(Threads::number_of_threads() == 0, "for bootstrap only");
jint old_value = *dest;
if (old_value == compare_value)
*dest = exchange_value;
return old_value;
}
jlong os::atomic_cmpxchg_long_bootstrap(jlong exchange_value, volatile jlong* dest, jlong compare_value) {
// try to use the stub:
cmpxchg_long_func_t* func = CAST_TO_FN_PTR(cmpxchg_long_func_t*, StubRoutines::atomic_cmpxchg_long_entry());
if (func != NULL) {
os::atomic_cmpxchg_long_func = func;
return (*func)(exchange_value, dest, compare_value);
}
assert(Threads::number_of_threads() == 0, "for bootstrap only");
jlong old_value = *dest;
if (old_value == compare_value)
*dest = exchange_value;
return old_value;
}
jint os::atomic_add_bootstrap(jint add_value, volatile jint* dest) {
// try to use the stub:
add_func_t* func = CAST_TO_FN_PTR(add_func_t*, StubRoutines::atomic_add_entry());
if (func != NULL) {
os::atomic_add_func = func;
return (*func)(add_value, dest);
}
assert(Threads::number_of_threads() == 0, "for bootstrap only");
return (*dest) += add_value;
}
xchg_func_t* os::atomic_xchg_func = os::atomic_xchg_bootstrap;
cmpxchg_func_t* os::atomic_cmpxchg_func = os::atomic_cmpxchg_bootstrap;
cmpxchg_long_func_t* os::atomic_cmpxchg_long_func = os::atomic_cmpxchg_long_bootstrap;
add_func_t* os::atomic_add_func = os::atomic_add_bootstrap;
#endif // !_LP64 && !COMPILER2
#if defined(__sparc) && defined(COMPILER2) && defined(_GNU_SOURCE)
// See file build/solaris/makefiles/$compiler.make
// For compiler1 the architecture is v8 and frps isn't present in v8
extern "C" void _mark_fpu_nosave() {
__asm__ __volatile__ ("wr %%g0, 0, %%fprs \n\t" : : :);
}
#endif //defined(__sparc) && defined(COMPILER2)