I did a few read-throughs of the changes for:

    JDK-8366659 ObjectMonitor::wait() can deadlock with a suspension request

I noticed various nits and typos and didn't want put them in that PR
since the fix might need backporting.

Here's what I have found so far:

jdk/src/hotspot/share/runtime/objectMonitor.cpp

189: // Once we have formed a doubly linked list it's easy to find the
190: // successor (A), wake it up, have it remove itself, and update the
191: // tail pointer, as seen in and 3) below.

Typo: s/, as seen in and 3) below./see 3) below./
to match the style in #1's reference to #2.


735: assert(!has_successor(current), "invariant");
736: assert(has_owner(current), "invariant");

The usual order is check 'owner' then check 'successor'.

943: assert(!has_successor(current), "invariant");
944: assert(has_owner(current), "invariant");

The usual order is check 'owner' then check 'successor'.

964: assert(!has_successor(current), "invariant");
965: assert(!has_owner(current), "invariant");

1041: // We can find that we were unpark()ed and redesignated _succ while
1042: // we were spinning. That's harmless. If we iterate and call park(),
1043: // park() will consume the event and return immediately and we'll
1044: // just spin again. This pattern can repeat, leaving _succ to simply
1045: // spin on a CPU.
1046:
1047: if (has_successor(current)) clear_successor();

Please put the 'clear_successor()' on a line by itself and add
enclosing '{' and '}'.

Also, there should be a single space after the periods in the comments
and not double spaces.

1060: // *must* retry _owner before parking.

Nit: extra space after 'retry' and before '_owner'.

1103: // of carriers. This can happen, for example, if a mixed of unmounted and

Typo: s/if a mixed of/if a mix of/

1153: // The lock is still contested.

Typo: s/contested/contended/

1157: if (has_successor(current)) clear_successor();

Please put the 'clear_successor()' on a line by itself and add
enclosing '{' and '}'.

1170: if (has_successor(current)) clear_successor();

Please put the 'clear_successor()' on a line by itself and add
enclosing '{' and '}'.

Also needs this comment:
    // Note that we don't need to do OrderAccess::fence() after clearing
    // _succ here, since we own the lock.

1210: if (has_successor(current)) clear_successor();
1211: if (waiter == nullptr) delete node; // for Object.wait() don't delete yet

Please put each of the statement parts on a line by itself and add
enclosing '{' and '}'.

Also needs this comment after the clear_successor() call:
    // Note that we don't need to do OrderAccess::fence() after clearing
    // _succ here, since we own the lock.

1249: if (has_successor(current)) clear_successor();

Please put the 'clear_successor()' on a line by itself and add
enclosing '{' and '}'.

1270: if (has_successor(current)) clear_successor();

Also needs this comment:
    // Note that we don't need to do OrderAccess::fence() after clearing
    // _succ here, since we own the lock.

Please put the 'clear_successor()' on a line by itself and add
enclosing '{' and '}'.

1561: // then calls exit(). Exit release the lock by setting O._owner to null.

Typo: s/Exit release the lock/Exit releases the lock/

There should be a single space after each period in this comment
block and not double spaces.

1563: // notify() operation moves T1 from O's waitset to O's entry_list. T2 then
1564: // release the lock "O".

Typo: s/release the lock/releases the lock/

1601: // Note that spinners in Enter() also set _succ non-null.

This reference to 'Enter()' needs to be updated (I think).

1920: if (has_successor(current)) clear_successor();

Please put the 'clear_successor()' on a line by itself and add
enclosing '{' and '}'.

2468: clear_successor();
Needs this comment:
    // Note that we don't need to do OrderAccess::fence() after clearing
    // _succ here, since we own the lock.