RFR: 8267954: Shared classes that failed to load should not be loaded again [v2]

[Ioi Lam]

On Wed, 9 Jun 2021 19:04:35 GMT, Yumin Qi <minqi at openjdk.org> wrote:

>> Hi, Please review
>>   Shared classes should not be loaded again at failed loading from CDS. In the failed case, restore_unshareable_info failed due to some reason (OOM), but the class already polluted and failed to be loaded again.
>>   Using the unused bit in _misc_flags indicates shared loading status to prevent it from being loaded again.
>> 
>> Tests: tier1,tier2,tier3,tier4,tier7
>> Local tests: jtreg/hotspot/runtime/cds
>> TestDynamicDumpAtOom.java (which failed in tier7) with variant allocation sizes (used to reproduce the failure) passed.
>> 
>> Thanks
>> Yumin
>
> Yumin Qi has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Move SharedClassLoadingMark to systemDictionaryShared.hpp

src/hotspot/share/classfile/systemDictionary.cpp line 1297:

> 1295: #if INCLUDE_CDS
> 1296:       SharedClassLoadingMark slm(THREAD, k);
> 1297: #endif

I think it's cleaner to use the CDS_ONLY macro. This macro is already used elsewhere in this file.


CDS_ONLY(SharedClassLoadingMark slm(THREAD, k));

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PR: https://git.openjdk.java.net/jdk/pull/4434