RFR (L/XXS) cleanup non-indent white space issues (8046758)

Daniel D. Daugherty daniel.daugherty at oracle.com
Mon Jun 16 23:26:43 UTC 2014


Thanks for the fast review!


On 6/16/14 4:16 PM, serguei.spitsyn at oracle.com wrote:
> I Dan,
>
> You are crazy enough to fix these! ;)

Yes I am, but only one (large) chunk at a time...


 > No need to re-review if you decide to fix the above.

For your comments about the incorrect indents, I'm going to
requote this (in particular the last sentence):

 > These non-indent white space cleanups were done in preparation for the
 > cleanup bucket from the Contended Locking project; these changes were 
made
 > by my do_space_filter.ksh script. The script does not fix everything in
 > these files that is not in sync with HotSpot style, but it does fix a
 > large portion of them. In particular, the do_space_filter.ksh script does
 > _not_ fix incorrect indenting; I'm mulling on a different solution for
 > that problem.

I don't have an automated fix for the indent problem yet, but I'm working
on it. Because the Contended Locking project is being done in phases, I
need to have script do the work every time I rebase all the buckets.

For the XXX is no longer aligned comments, I'm going to have to make a
manual pass for such things, but that's not what this webrev is for.
This webrev is for the things that can be automatically fixed by my
do_space_filter.ksh script; no manual changes in this round.

Please let me know if you're OK with these resolutions.

More replies embedded below...


>
> It looks good.
> Some nits...
>
> src/share/vm/runtime/objectMonitor.hpp
>
>   The style in this file is to align the closing brackets:
>     static int recursions_offset_in_bytes()  { return offset_of(ObjectMonitor, _recursions); }
> -  static int cxq_offset_in_bytes()         { return offset_of(ObjectMonitor, _cxq) ;       }
> -  static int succ_offset_in_bytes()        { return offset_of(ObjectMonitor, _succ) ;      }
> +  static int cxq_offset_in_bytes()         { return offset_of(ObjectMonitor, _cxq);       }
> +  static int succ_offset_in_bytes()        { return offset_of(ObjectMonitor, _succ);      }
>     static int EntryList_offset_in_bytes()   { return offset_of(ObjectMonitor, _EntryList);  }

Aligning the closing brackets will away in the manual fixes stage.


> The style in this file is to align the comments:
>     volatile intptr_t  _recursions;   // recursion count, 0 for first entry
>    private:
> -  int OwnerIsThread ;               // _owner is (Thread *) vs SP/BasicLock
> -  ObjectWaiter * volatile _cxq ;    // LL of recently-arrived threads blocked on entry.
> +  int OwnerIsThread;               // _owner is (Thread *) vs SP/BasicLock
> +  ObjectWaiter * volatile _cxq;    // LL of recently-arrived threads blocked on entry.
>                                       // The list is actually composed of WaitNodes, acting
>                                       // as proxies for Threads.
>    protected:
> -  ObjectWaiter * volatile _EntryList ;     // Threads blocked on entry or reentry.
> +  ObjectWaiter * volatile _EntryList;     // Threads blocked on entry or reentry.
>    private:
> -  Thread * volatile _succ ;          // Heir presumptive thread - used for futile wakeup throttling
> -  Thread * volatile _Responsible ;
> -  int _PromptDrain ;                // rqst to drain cxq into EntryList ASAP
> +  Thread * volatile _succ;          // Heir presumptive thread - used for futile wakeup throttling
> +  Thread * volatile _Responsible;
> +  int _PromptDrain;                // rqst to drain cxq into EntryList ASAP
>   
> -  volatile int _Spinner ;           // for exit->spinner handoff optimization
> -  volatile int _SpinFreq ;          // Spin 1-out-of-N attempts: success rate
> -  volatile int _SpinClock ;
> -  volatile int _SpinDuration ;
> -  volatile intptr_t _SpinState ;    // MCS/CLH list of spinners
> +  volatile int _Spinner;           // for exit->spinner handoff optimization
> +  volatile int _SpinFreq;          // Spin 1-out-of-N attempts: success rate
> +  volatile int _SpinClock;
> +  volatile int _SpinDuration;
> +  volatile intptr_t _SpinState;    // MCS/CLH list of spinners

During the reorder fields and cache line alignment bucket, a bunch of the
fields will move around and I'll have to make a manual pass to align the
comments consistently. Of course, the same comment indent is not used
consistently throughout the entire class.


> src/share/vm/runtime/objectMonitor.cpp
>
> It is surprising that there are so many fragments with incorrect 
> indent (3 or 4) in the loops and conditions!
> Some examples are:
>   322   // we forgo posting JVMTI events and firing DTRACE probes.
>   323   if (Knob_SpinEarly && TrySpin (Self) > 0) {
>   324      assert(_owner == Self      , "invariant");
>   325      assert(_recursions == 0    , "invariant");
>   326      assert(((oop)(object()))->mark() == markOopDesc::encode(this), "invariant");
>   327      Self->_Stalled = 0;
>   328      return;
>   329   }
>   521     for (;;) {
>   522         node._next = nxt = _cxq;
>   523         if (Atomic::cmpxchg_ptr(&node, &_cxq, nxt) == nxt) break;
>   524
>   525         // Interference - the CAS failed because _cxq changed.  Just retry.
>   526         // As an optional optimization we retry the lock.
>   527         if (TryLock (Self) > 0) {
>   528             assert(_succ != Self         , "invariant");
>   529             assert(_owner == Self        , "invariant");
>   530             assert(_Responsible != Self  , "invariant");
>   531             return;
>   532         }
>   533     }
>   584         if ((SyncFlags & 2) && _Responsible == NULL) {
>   585            Atomic::cmpxchg_ptr(Self, &_Responsible, NULL);
>   586         }
>   587
>   588         // park self
>   589         if (_Responsible == Self || (SyncFlags & 1)) {
>   590             TEVENT(Inflated enter - park TIMED);
>   591             Self->_ParkEvent->park((jlong) RecheckInterval);
>   592             // Increase the RecheckInterval, but clamp the value.
>   593             RecheckInterval *= 8;
>   594             if (RecheckInterval > 1000) RecheckInterval = 1000;
>   595         } else {
>   596             TEVENT(Inflated enter - park UNTIMED);
>   597             Self->_ParkEvent->park();
>   598         }
>
>   627         if ((Knob_ResetEvent & 1) && Self->_ParkEvent->fired()) {
>   628            Self->_ParkEvent->reset();
>   629            OrderAccess::fence();
>   630         }
>
> The '_recursions' is still unaligned:
>
>   379       // thread that suspended us.
>   380       //
>   381           _recursions = 0;
>   382       _succ = NULL;
>   383       exit(false, Self);

These will get fixed automatically when I get the next tool
working...


> The  back slashes are supposed to be aligned:
> 1381 #define CHECK_OWNER()                                                             \
> 1382   do {                                                                            \
> 1383     if (THREAD != _owner) {                                                       \
> 1384       if (THREAD->is_lock_owned((address) _owner)) {                              \
> 1385         _owner = THREAD;  /* Convert from basiclock addr to Thread addr */       \
> 1386         _recursions = 0;                                                          \
> 1387         OwnerIsThread = 1;                                                       \
> 1388       } else {                                                                    \
> 1389         TEVENT(Throw IMSX);                                                     \
> 1390         THROW(vmSymbols::java_lang_IllegalMonitorStateException());               \
> 1391       }                                                                           \
> 1392     }                                                                             \
> 1393   } while (false)

The backslashes will be fixed when I do a manual pass.


> Unaligned comments:
>   983          OrderAccess::release_store_ptr(&_owner, NULL);   // drop the lock
>   984          OrderAccess::storeload();                         // See if we need to wake a successor

This will be fixed when I do a manual pass.


> Extra spaces before the comma:
> 1092           assert(w != NULL              , "invariant");
> 1131           assert(w != NULL              , "invariant");

Fixing interior parameter and comma spacing will have to be done
manually. The script can handle patterns that are well anchored
at the beginning and end of a line, but the interior stuff is
much more difficult to get right without unintended side effects.


> src/share/vm/runtime/synchronizer.cpp
>
> There are so many fragments with incorrect indent (3 or 4) in the 
> loops and conditions.
> Some examples:
>
>   163   if (dhw == NULL) {
>   164      // Recursive stack-lock.
>   165      // Diagnostics -- Could be: stack-locked, inflating, inflated.
>   166      mark = object->mark();
>   167      assert(!mark->is_neutral(), "invariant");
>   168      if (mark->has_locker() && mark != markOopDesc::INFLATING()) {
>   169         assert(THREAD->is_lock_owned((address)mark->locker()), "invariant");
>   170      }
>   171      if (mark->has_monitor()) {
>   172         ObjectMonitor * m = mark->monitor();
>   173         assert(((oop)(m->object()))->mark() == mark, "invariant");
>   174         assert(m->is_entered(THREAD), "invariant");
>   175      }
>   176      return;
>   177   }
>   428 struct SharedGlobals {
>   429     // These are highly shared mostly-read variables.
>   430     // To avoid false-sharing they need to be the sole occupants of a $ line.
>   431     double padPrefix[8];
>   432     volatile int stwRandom;
>   433     volatile int stwCycle;
>   434
>   435     // Hot RW variables -- Sequester to avoid false-sharing
>   436     double padSuffix[16];
>   437     volatile int hcSequence;
>   438     double padFinal[8];
>   439 };
>   498            if ((YieldThenBlock++) >= 16) {
>   499               Thread::current()->_ParkEvent->park(1);
>   500            } else {
>   501               os::NakedYield();
>   502            }
>   963             for (int i = Self->omFreeProvision; --i >= 0 && gFreeList != NULL;) {
>   964                 MonitorFreeCount--;
>   965                 ObjectMonitor * take = gFreeList;
>   966                 gFreeList = take->FreeNext;
>   967                 guarantee(take->object() == NULL, "invariant");
>   968                 guarantee(!take->is_busy(), "invariant");
>   969                 take->Recycle();
>   970                 omRelease(Self, take, false);
>   971             }
> 1329       if (Atomic::cmpxchg_ptr (markOopDesc::encode(m), object->mark_addr(), mark) != mark) {
> 1330           m->set_object(NULL);
> 1331           m->set_owner(NULL);
> 1332           m->OwnerIsThread = 0;
> 1333           m->Recycle();
> 1334           omRelease(Self, m, true);
> 1335           m = NULL;
> 1336           continue;
> 1337           // interference - the markword changed - just retry.
> 1338           // The state-transitions are one-way, so there's no chance of
> 1339           // live-lock -- "Inflated" is an absorbing state.
> 1340       }

These will get fixed automatically when I get the next tool
working...


> Unaligned comments:
>   129 static volatile intptr_t ListLock = 0;      // protects global monitor free-list cache
>   130 static volatile int MonitorFreeCount  = 0;      // # on gFreeList
>   131 static volatile int MonitorPopulation = 0;      // # Extant -- in circulation

This will get fixed during a manual pass.


> src/share/vm/runtime/thread.cpp
>
> Incorrect indent (also, see: 4462, 4468-4500) :
> 4369   if (Atomic::cmpxchg (1, adr, 0) == 0) {
> 4370      return;   // normal fast-path return
> 4371   }
> 4372
> 4373   // Slow-path : We've encountered contention -- Spin/Yield/Block strategy.
> 4374   TEVENT(SpinAcquire - ctx);
> 4375   int ctr = 0;
> 4376   int Yields = 0;
> 4377   for (;;) {
> 4378      while (*adr != 0) {
> 4379         ++ctr;
> 4380         if ((ctr & 0xFFF) == 0 || !os::is_MP()) {
> 4381            if (Yields > 5) {
> 4382              os::naked_short_sleep(1);
> 4383            } else {
> 4384              os::NakedYield();
> 4385              ++Yields;
> 4386            }
> 4387         } else {
> 4388            SpinPause();
> 4389         }
> 4390      }
> 4391      if (Atomic::cmpxchg(1, adr, 0) == 0) return;
> 4392   }

These will get fixed automatically when I get the next tool
working...

>
> No need to re-review if you decide to fix the above.
>
> Thanks,
> Serguei
>
>
> On 6/16/14 10:45 AM, Daniel D. Daugherty wrote:
>> Greetings,
>>
>> I have the fix for the following bug ready for JDK9 RT_Baseline:
>>
>>     JDK-8046758 cleanup non-indent white space issues prior to Contended
>>                 Locking cleanup bucket
>> https://bugs.openjdk.java.net/browse/JDK-8046758
>>
>> This is both a (L)arge and e(X)tra e(X)tra (S)mall review! Here is the
>> URL for the (L)arge webrev:
>>
>> http://cr.openjdk.java.net/~dcubed/8046758-webrev/0-jdk9-hs-rt/
>>
>> Since these are white space fixes, I recommend the udiff links instead
>> of the frames links. Of course, some folks prefer the patch file itself
>> for white space fixes.
>>
>> Here is the URL for the e(X)tra e(X)tra (S)mall webrev which was 
>> generated
>> with a version of webrev that ignores all whitespace changes:
>>
>> http://cr.openjdk.java.net/~dcubed/8046758-webrev/0-jdk9-hs-rt-no_ws/
>>
>> Again, I recommend the udiff links since that's the fastest way to see
>> that webrev_no_ws found no non-white space changes. The patch file for
>> this webrev shows all the white space changes.
>>
>> These non-indent white space cleanups were done in preparation for the
>> cleanup bucket from the Contended Locking project; these changes were 
>> made
>> by my do_space_filter.ksh script. The script does not fix everything in
>> these files that is not in sync with HotSpot style, but it does fix a
>> large portion of them. In particular, the do_space_filter.ksh script 
>> does
>> _not_ fix incorrect indenting; I'm mulling on a different solution for
>> that problem.
>>
>> Thanks, in advance, for any comments, questions or suggestions.
>>
>> At the end of the review cycle for this fix, I will attach the 
>> version of
>> the do_space_filter.ksh script used to do the work to JDK-8046758.
>>
>> Dan
>



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