456 int os::Linux::get_fpu_control_word(void) {
457 return 0;
458 }
459
460 void os::Linux::set_fpu_control_word(int fpu_control) {
461 }
462
463 // Check that the linux kernel version is 2.4 or higher since earlier
464 // versions do not support SSE without patches.
465 bool os::supports_sse() {
466 return true;
467 }
468
469 bool os::is_allocatable(size_t bytes) {
470 return true;
471 }
472
473 ////////////////////////////////////////////////////////////////////////////////
474 // thread stack
475
476 size_t os::Linux::min_stack_allowed = 64 * K;
477
478 // return default stack size for thr_type
479 size_t os::Linux::default_stack_size(os::ThreadType thr_type) {
480 // default stack size (compiler thread needs larger stack)
481 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
482 return s;
483 }
484
485 size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
486 // Creating guard page is very expensive. Java thread has HotSpot
487 // guard page, only enable glibc guard page for non-Java threads.
488 return (thr_type == java_thread ? 0 : page_size());
489 }
490
491 // Java thread:
492 //
493 // Low memory addresses
494 // +------------------------+
495 // | |\ JavaThread created by VM does not have glibc
496 // | glibc guard page | - guard, attached Java thread usually has
497 // | |/ 1 page glibc guard.
498 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
499 // | |\
|
456 int os::Linux::get_fpu_control_word(void) {
457 return 0;
458 }
459
460 void os::Linux::set_fpu_control_word(int fpu_control) {
461 }
462
463 // Check that the linux kernel version is 2.4 or higher since earlier
464 // versions do not support SSE without patches.
465 bool os::supports_sse() {
466 return true;
467 }
468
469 bool os::is_allocatable(size_t bytes) {
470 return true;
471 }
472
473 ////////////////////////////////////////////////////////////////////////////////
474 // thread stack
475
476 size_t os::Posix::_compiler_thread_min_stack_allowed = 64 * K;
477 size_t os::Posix::_java_thread_min_stack_allowed = 64 * K;
478 size_t os::Posix::_vm_internal_thread_min_stack_allowed = 64 * K;
479
480 // return default stack size for thr_type
481 size_t os::Posix::default_stack_size(os::ThreadType thr_type) {
482 // default stack size (compiler thread needs larger stack)
483 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
484 return s;
485 }
486
487 size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
488 // Creating guard page is very expensive. Java thread has HotSpot
489 // guard page, only enable glibc guard page for non-Java threads.
490 return (thr_type == java_thread ? 0 : page_size());
491 }
492
493 // Java thread:
494 //
495 // Low memory addresses
496 // +------------------------+
497 // | |\ JavaThread created by VM does not have glibc
498 // | glibc guard page | - guard, attached Java thread usually has
499 // | |/ 1 page glibc guard.
500 // P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
501 // | |\
|