RFR: JDK-8153187: Convert TraceWorkGang to use unified logging

[Mikael Gerdin]

Hi Bengt,

On 2016-03-31 14:30, Bengt Rutisson wrote:
>
> Hi everyone,
>
> Could I have a couple of reviews for this change?
>
> http://cr.openjdk.java.net/~brutisso/8153187/webrev.00/

  312   log_develop_trace(gc, workgang)("Finished work gang: %s task: %s 
worker: %u thread: " PTR_FORMAT,
  313       name(), data._task->name(), data._worker_id, 
p2i(Thread::current()));
  314 }

Shouldn't the parameters on line 313 be aligned with the opening brace?

Otherwise looks good. There is no possibility of the code entering 
print_task_done from the VM thread so I agree that the code to handle 
that should be removed.

/Mikael

> https://bugs.openjdk.java.net/browse/JDK-8153187
>
> The logging guarded by TraceWorkGang should be converted to use the
> unified logging framework.
>
> The logging now has this format:
>
> [0,509s][trace][gc,workgang] GC(0) Running work gang: GC Thread#1 task:
> ParPreserveCMReferents worker: 0
> [0,509s][trace][gc,workgang] GC(0) Running work gang: GC Thread#0 task:
> ParPreserveCMReferents worker: 1
> [0,509s][trace][gc,workgang] GC(0) Running work gang: GC Thread#3 task:
> ParPreserveCMReferents worker: 3
> [0,509s][trace][gc,workgang] GC(0) Running work gang: GC Thread#2 task:
> ParPreserveCMReferents worker: 2
> [0,510s][trace][gc,workgang] GC(0) Finished work gang: GC Thread#2 task:
> ParPreserveCMReferents worker: 2 thread: 0x00007f161c039800
> [0,510s][trace][gc,workgang] GC(0) Finished work gang: GC Thread#1 task:
> ParPreserveCMReferents worker: 0 thread: 0x00007f161c037800
> [0,510s][trace][gc,workgang] GC(0) Finished work gang: GC Thread#3 task:
> ParPreserveCMReferents worker: 3 thread: 0x00007f161c03b800
> [0,510s][trace][gc,workgang] GC(0) Finished work gang: GC Thread#0 task:
> ParPreserveCMReferents worker: 1 thread: 0x00007f161c035800
>
> The "finished" log line has a slightly different format comapred to
> before. It used to be two lines, like this:
>
> Finished work gang GC Thread#1 task Parallel verify task worker 0
>    T: 0x00007f39c4038800  VM_thread: 0
>
> The second line contained the thread pointer and an int that was always
> 0 since GangWorkers are never VM threads. I skipped the VM_thread info
> and moved the thread pointer to the first line.
>
> Note that TraceWorkGang was a develop flag so there should be no tools
> out there that rely on this format.
>
> Thanks,
> Bengt
>