Request for review (M): 7132070: Use a mach_port_t as the OSThread thread_id rather than pthread_t on BSD/OSX

[Daniel D. Daugherty]

On 2/15/12 1:34 PM, Staffan Larsen wrote:
> That's what I guessed. So essentially all the code the is in the #else part of #ifdef _ALLBSD_SOURCE under src/os/bsd can be removed and the #ifdef _ALLBSD_SOURCE can be skipped. Like so:
>
> #ifdef _ALLBSD_SOURCE
>     xxx;
> #else
>     yyy;
> #endif
>
> can be changed to:
>
> xxx;
>
> I'll volunteer to do that cleanup.

I think that would make the eventual merge of all the "nixes"
more difficult...

Dan


> /Staffan
>
> On 15 feb 2012, at 21:24, Daniel D. Daugherty wrote:
>
>> The src/os/bsd code was derived from the src/os/linux code.
>> #ifdef _ALLBSD_SOURCE was used to flag (most) changes relative
>> to Linux for the BSD port. The #ifdef'ing is not perfect because
>> the Linux code also evolved as the BSD port was being done and
>> also because sometimes folks forgot to #ifdef their changes...
>>
>> Eventually, there is supposed to be a rework/rewrite in this area
>> where all the "nixes" share code. It won't be under src/os/posix,
>> but we'll think of some good name if the project ever gets done...
>>
>> Dan
>>
>>
>> On 2/15/12 12:30 PM, Staffan Larsen wrote:
>>> Reading this again, I wonder: What is the purpose of _ALLBSD_SOURCE in a file under 'src/os/bsd'? Are there platforms that are 'bad', but do not define _ALLBSD_SOURCE?
>>>
>>> /Staffan
>>>
>>>
>>> On 15 feb 2012, at 16:16, Daniel D. Daugherty wrote:
>>>
>>>> The _ALLBSD_SOURCE symbol is defined by the HotSpot Makefile infrastructure.
>>>> It is used to identify code specific to the BSD family of OSes.
>>>> The __APPLE__ symbol is defined by the Apple compiler(s) and it is used to
>>>> identify code specific to MacOS X.
>>>>
>>>> Typically you'll see something like:
>>>>
>>>> #ifdef _ALLBSD_SOURCE
>>>>
>>>> <code that works on all BSDs>
>>>>
>>>> #ifdef __APPLE__
>>>> <code specific to MacOS X>
>>>> #else
>>>> <code for other BSDs>
>>>> #endif // __APPLE__
>>>> #endif // _ALLBSD_SOURCE
>>>>
>>>> As for building on non-MacOS X BSDs, that would be nice, but we
>>>> don't have the infrastructure to do it.
>>>>
>>>> Dan
>>>>
>>>> On 2/15/12 6:57 AM, Mikael Gerdin wrote:
>>>>> Hi Staffan,
>>>>>
>>>>> It looks like you're adding Mac-specific stuff like thread_t and calls to ::mach_thread_self() inside _ALLBSD_SOURCE #ifdefs, are you sure this won't break BSD builds?
>>>>> Does the OSX compiler define _ALLBSD_SOURCE or is that for (free|net|open)bsd?
>>>>> It's too bad we don't do regular builds on any of the BSDs, otherwise this would have been easier to figure out.
>>>>>
>>>>> /Mikael
>>>>>
>>>>>
>>>>> On 2012-02-15 11:29, Staffan Larsen wrote:
>>>>>> Please review the following change:
>>>>>>
>>>>>> Bug: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7132070
>>>>>>
>>>>>> Webrev: http://cr.openjdk.java.net/~sla/7132070/webrev.00/
>>>>>>
>>>>>> This changes the value returned by OSThread::thread_id() and
>>>>>> os::current_thread_id() on macosx to return the mach thread_t instead of
>>>>>> pthread_t. There is a separate method OSThread:pthread_id() that returns
>>>>>> the pthread_t.
>>>>>>
>>>>>> The reason for this change is both that JFR would like a 4 byte value
>>>>>> for thread id, and that SA requires access to the thread_t.
>>>>>>
>>>>>> Thanks,
>>>>>> /Staffan