Request for approval: 6929067: Stack guard pages should be removed when thread is detached

[David Holmes]

Looking further into this, isn't the only thread that can be affected by 
this the main thread? So we could perform this only if 
os::is_initial_thread() returns true?

David

David Holmes said the following on 08/16/10 11:43:
> Andrew, Coleen,
> 
> Andrew Haley said the following on 03/12/10 19:44:
>> On 03/11/2010 09:06 PM, Coleen Phillimore wrote:
>>> I've added the test to the changeset and a script to run in our harness.
>>>
>>> Also in os_linux.cpp, I changed the SYS_gettid call to go through our
>>> os::Linux::gettid() because on at least one linux, syscall() returns a
>>> long int which gets a compilation warning with %d.
>>>
>>> open webrev at http://cr.openjdk.java.net/~coleenp/6929067/
>>> bug link at http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6929067
>>>
>>> Andrew, please have a look since you're the contributor.
>>
>> That's OK, but you don't need SYS_gettid.
>> Please look at 
>> http://cr.openjdk.java.net/~aph/6929067-jdk7-webrev-4/hotspot.patch
>> I changed to "/proc/self/maps", as you requested.  I think this is 
>> better.
> 
> It looks like the use of /proc/self/maps can be a thread termination 
> bottleneck. Is there a way to determine whether this functionality is 
> needed for the current thread without actually reading the map file?
> 
> Thanks,
> David Holmes
>