changeset in /hg/icedtea6: 2008-03-10 Gary Benson <gbenson at red...
Gary Benson
gbenson at redhat.com
Mon Mar 10 07:37:27 PDT 2008
changeset bb65029089bb in /hg/icedtea6
details: http://icedtea.classpath.org/hg/icedtea6?cmd=changeset;node=bb65029089bb
description:
2008-03-10 Gary Benson <gbenson at redhat.com>
* ports/hotspot/src/os_cpu/linux_zero/vm/os_linux_zero.cpp
(current_stack_region): Rewritten to cope with guard pages and ia64.
(default_stack_size, default_guard_size): Comment fixes.
diffstat:
2 files changed, 74 insertions(+), 64 deletions(-)
ChangeLog | 6
ports/hotspot/src/os_cpu/linux_zero/vm/os_linux_zero.cpp | 132 +++++++-------
diffs (166 lines):
diff -r 3547877ecc7b -r bb65029089bb ChangeLog
--- a/ChangeLog Fri Mar 07 12:56:28 2008 -0500
+++ b/ChangeLog Mon Mar 10 10:37:21 2008 -0400
@@ -1,3 +1,9 @@ 2008-03-07 Joshua Sumali <jsumali at redh
+2008-03-10 Gary Benson <gbenson at redhat.com>
+
+ * ports/hotspot/src/os_cpu/linux_zero/vm/os_linux_zero.cpp
+ (current_stack_region): Rewritten to cope with guard pages and ia64.
+ (default_stack_size, default_guard_size): Comment fixes.
+
2008-03-07 Joshua Sumali <jsumali at redhat.com>
* rt/net/sourceforge/jnlp/security/CertsInfoPane.java: Fix null pointer.
diff -r 3547877ecc7b -r bb65029089bb ports/hotspot/src/os_cpu/linux_zero/vm/os_linux_zero.cpp
--- a/ports/hotspot/src/os_cpu/linux_zero/vm/os_linux_zero.cpp Fri Mar 07 12:56:28 2008 -0500
+++ b/ports/hotspot/src/os_cpu/linux_zero/vm/os_linux_zero.cpp Mon Mar 10 10:37:21 2008 -0400
@@ -171,7 +171,6 @@ bool os::Linux::supports_variable_stack_
size_t os::Linux::default_stack_size(os::ThreadType thr_type)
{
- // default stack size (compiler thread needs larger stack)
#ifdef _LP64
size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
#else
@@ -182,73 +181,78 @@ size_t os::Linux::default_stack_size(os:
size_t os::Linux::default_guard_size(os::ThreadType thr_type)
{
- // Creating guard page is very expensive. Java thread has HotSpot
- // guard page, only enable glibc guard page for non-Java threads.
+ // Only enable glibc guard pages for non-Java threads
+ // (Java threads have HotSpot guard pages)
return (thr_type == java_thread ? 0 : page_size());
}
-// Java thread:
-//
-// Low memory addresses
-// +------------------------+
-// | |\ JavaThread created by VM does not have glibc
-// | glibc guard page | - guard, attached Java thread usually has
-// | |/ 1 page glibc guard.
-// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
-// | |\
-// | HotSpot Guard Pages | - red and yellow pages
-// | |/
-// +------------------------+ JavaThread::stack_yellow_zone_base()
-// | |\
-// | Normal Stack | -
-// | |/
-// P2 +------------------------+ Thread::stack_base()
-//
-// Non-Java thread:
-//
-// Low memory addresses
-// +------------------------+
-// | |\
-// | glibc guard page | - usually 1 page
-// | |/
-// P1 +------------------------+ Thread::stack_base() - Thread::stack_size()
-// | |\
-// | Normal Stack | -
-// | |/
-// P2 +------------------------+ Thread::stack_base()
-//
-// ** P1 (aka bottom) and size ( P2 = P1 - size) are the address and stack size returned from
-// pthread_attr_getstack()
-
-static void current_stack_region(address* bottom, size_t* size) {
+static void current_stack_region(address *bottom, size_t *size)
+{
+ pthread_attr_t attr;
+ int res = pthread_getattr_np(pthread_self(), &attr);
+ if (res != 0) {
+ if (res == ENOMEM) {
+ vm_exit_out_of_memory(0, "pthread_getattr_np");
+ }
+ else {
+ fatal1("pthread_getattr_np failed with errno = %d", res);
+ }
+ }
+
+ address stack_bottom;
+ size_t stack_bytes;
+ res = pthread_attr_getstack(&attr, (void **) &stack_bottom, &stack_bytes);
+ if (res != 0) {
+ fatal1("pthread_attr_getstack failed with errno = %d", res);
+ }
+ address stack_top = stack_bottom + stack_bytes;
+
+ // The block of memory returned by pthread_attr_getstack() includes
+ // guard pages where present. We need to trim these off.
+ size_t page_bytes = os::Linux::page_size();
+ assert(((intptr_t) stack_bottom & (page_bytes - 1)) == 0, "unaligned stack");
+
+ size_t guard_bytes;
+ res = pthread_attr_getguardsize(&attr, &guard_bytes);
+ if (res != 0) {
+ fatal1("pthread_attr_getguardsize failed with errno = %d", res);
+ }
+ int guard_pages = align_size_up(guard_bytes, page_bytes) / page_bytes;
+ assert(guard_bytes == guard_pages * page_bytes, "unaligned guard");
+
+#ifdef IA64
+ // IA64 has two stacks sharing the same area of memory, a normal
+ // stack growing downwards and a register stack growing upwards.
+ // Guard pages, if present, are in the centre. This code splits
+ // the stack in two even without guard pages, though in theory
+ // there's nothing to stop us allocating more to the normal stack
+ // or more to the register stack if one or the other were found
+ // to grow faster.
+ int total_pages = align_size_down(stack_bytes, page_bytes) / page_bytes;
+ stack_bottom += (total_pages - guard_pages) / 2 * page_bytes;
+#endif // IA64
+
+ stack_bottom += guard_bytes;
+
+ pthread_attr_destroy(&attr);
+
+ // The initial thread has a growable stack, and the size reported
+ // by pthread_attr_getstack is the maximum size it could possibly
+ // be given what currently mapped. This can be huge, so we cap it.
if (os::Linux::is_initial_thread()) {
- // initial thread needs special handling because pthread_getattr_np()
- // may return bogus value.
- *bottom = os::Linux::initial_thread_stack_bottom();
- *size = os::Linux::initial_thread_stack_size();
- } else {
- pthread_attr_t attr;
-
- int rslt = pthread_getattr_np(pthread_self(), &attr);
-
- // JVM needs to know exact stack location, abort if it fails
- if (rslt != 0) {
- if (rslt == ENOMEM) {
- vm_exit_out_of_memory(0, "pthread_getattr_np");
- } else {
- fatal1("pthread_getattr_np failed with errno = %d", rslt);
- }
- }
-
- if (pthread_attr_getstack(&attr, (void **)bottom, size) != 0 ) {
- fatal("Can not locate current stack attributes!");
- }
-
- pthread_attr_destroy(&attr);
-
- }
- assert(os::current_stack_pointer() >= *bottom &&
- os::current_stack_pointer() < *bottom + *size, "just checking");
+ stack_bytes = stack_top - stack_bottom;
+
+ if (stack_bytes > JavaThread::stack_size_at_create())
+ stack_bytes = JavaThread::stack_size_at_create();
+
+ stack_bottom = stack_top - stack_bytes;
+ }
+
+ assert(os::current_stack_pointer() >= stack_bottom, "should do");
+ assert(os::current_stack_pointer() < stack_top, "should do");
+
+ *bottom = stack_bottom;
+ *size = stack_top - stack_bottom;
}
address os::current_stack_base()
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