RFR (S): JDK-8129855: -XX:+IgnoreUnrecognizedVMOptions hides out of range VM options.

[Daniel D. Daugherty]

On 10/22/15, 10:26 AM, gerard ziemski wrote:
> hi all,
>
> Here is a rev2 updated with fixes based mainly on Dan's feedback. It 
> has 3 changes compared to rev1:
>
> #1 Fixed IgnoreUnrecognizedVMOptions.java test cases by correctly 
> setting the flags [Dan Daugherty]
>
> #2 Added another set of test cases, and rearranged them to keep types 
> together.
>
> #3 Fixed test/compiler/membars/DekkerTest since now that the 
> IgnoreUnrecognizedVMOptions works differently we have to re-arrange 
> the flags to make CICompilerCount=1 a valid value.
>
>
> http://cr.openjdk.java.net/~gziemski/8129855_rev2

src/share/vm/runtime/arguments.cpp
     No comments.

src/share/vm/runtime/globals.cpp
     L336:   get_locked_message_ext(buf, buflen);
     L337:   return Flag::NONE;
         It still feels strange to not get a return value from
         get_locked_message_ext() and always return Flag::NONE
         in this case.

         If not addressed here, it would be good to file a follow
         up bug that clarify how the extension mechanism fits in
         with the base mechanism.

src/share/vm/runtime/globals.hpp
     No comments.

test/compiler/membars/DekkerTest.java
     Perfect example of why left-to-right order eval means something.
     No other comments.

test/runtime/CommandLine/IgnoreUnrecognizedVMOptions.java
     L90: #1.4 develop & notproduct flag on product VM:
     L91: develop & !product_build        notproduct & !product_build
     L96: if (product) {
         The comment doesn't match the test code. This is not
         a !product_build config.

     L119: #1.6 malformed develop & notproduct flag on product VM:
     L120: develop & !product_build          .notproduct & !product_build
     L125: if (product) {
         The comment doesn't match the test code. This is not
         a !product_build config.

         Also L120 has '.notproduct' should be 'notproduct'.

Thumbs up. If you fix the above comment mis-matches, I don't
need to see another webrev.

Dan


>
>
> cheers
>
> On 09/28/2015 04:55 PM, gerard ziemski wrote:
>> hi all,
>>
>> We are fixing how IgnoreUnrecognizedVMOptions treats those flags 
>> whose values are out of range. Before the fix, the VM
>> would continue even if flag’s value was out of range, ex:
>>
>> java_old -XX:+IgnoreUnrecognizedVMOptions -XX:MinTLABSize=0 -version
>> size_t MinTLABSize=0 is outside the allowed range [ 1 ... 4294967295 ]
>> java version "1.9.0-internal-fastdebug"
>> Java(TM) SE Runtime Environment (build 
>> 1.9.0-internal-fastdebug-20150624183527.jesper.main2rt-b00)
>> Java HotSpot(TM) Server VM (build 
>> 1.9.0-internal-fastdebug-20150624183527.jesper.main2rt-b00, mixed mode)
>>
>> now, we correctly exit the VM with an error, ex:
>>
>> java_new -XX:+IgnoreUnrecognizedVMOptions -XX:MinTLABSize=0 -version
>> size_t MinTLABSize=0 is outside the allowed range [ 1 ... 
>> 18446744073709551615 ]
>> Improperly specified VM option 'MinTLABSize=0'
>> Error: Could not create the Java Virtual Machine.
>> Error: A fatal exception has occurred. Program will exit.
>>
>> In addition IgnoreUnrecognizedVMOptions nows strictly follows the 
>> spec as outlined in JDK-8129855. The behavior changes
>> depending on whether the build is product or debug.
>>
>> We also introduce a new test that verifies all known use cases that 
>> we care about.
>>
>> References:
>>       bugid: https://bugs.openjdk.java.net/browse/JDK-8129855
>>      webrev: http://cr.openjdk.java.net/~gziemski/8129855_rev0
>> discussion: 
>> http://mail.openjdk.java.net/pipermail/hotspot-dev/2015-June/019213.html
>>
>> Passes "JPRT hotspot" and "RBT testlist,noncolo.testlist quick"
>>
>>
>> cheers
>>
>