RFR: 8246405: Add GCLogPrecious functionality to log and report debug errors

Erik Österlund erik.osterlund at oracle.com
Wed Jun 3 15:01:53 UTC 2020


Hi Stefan,

Looks good.

/Erik

On 2020-06-03 10:42, Stefan Karlsson wrote:
> Hi all,
>
> Please review this patch to enhance the GCLogPrecious functionality 
> (JDK-8246405) to add support for a way to both log and generate a 
> crash report in debug builds.
>
> https://cr.openjdk.java.net/~stefank/8246405/webrev.01/
> https://bugs.openjdk.java.net/browse/JDK-8246405
>
> I've split out a patch where ZGC uses this functionality:
>
> https://cr.openjdk.java.net/~stefank/8246406/webrev.01/
> https://bugs.openjdk.java.net/browse/JDK-8246406
>
> Tested manually by running:
> (ulimit -v >low value>; ../build/fastdebug/jdk/bin/java -XX:+UseZGC 
> -Xmx18m -Xlog:gc* -version)
>
> and verified that it generates a hs_err file with the appropriate 
> information.
>
> On macOS the output points to the right file and line number:
>
> #  Internal Error (src/hotspot/share/gc/z/zVirtualMemory.cpp:46), 
> pid=67695, tid=8451
> #  Error: Failed to reserve enough address space for Java heap
>
> but since TOUCH_ASSERT_POISON isn't implemented we don't get registers 
> and the output contains the GCLogPrecious code:
>
> V  [libjvm.dylib+0xb3d95c]  VMError::report_and_die(int, char const*, 
> char const*, __va_list_tag*, Thread*, unsigned char*, void*, void*, 
> char const*, int, unsigned long)+0x670
> V  [libjvm.dylib+0xb3e083] VMError::report_and_die(Thread*, void*, 
> char const*, int, char const*, char const*, __va_list_tag*)+0x47
> V  [libjvm.dylib+0x334b48]  report_vm_error(char const*, int, char 
> const*, char const*, ...)+0x145
> V  [libjvm.dylib+0x48d629] 
> GCLogPrecious::vwrite_and_debug(LogTargetHandle, char const*, 
> __va_list_tag*, char const*, int)+0x81
> V  [libjvm.dylib+0xbbdf70] GCLogPreciousHandle::write_and_debug(char 
> const*, ...)+0x92
> V  [libjvm.dylib+0xbd833e] 
> ZVirtualMemoryManager::ZVirtualMemoryManager(unsigned long)+0xb6
>
> On Linux, where TOUCH_ASSERT_POISON is implemented, we get the last 
> parts cut away:
>
> V  [libjvm.so+0x1857179] 
> ZVirtualMemoryManager::ZVirtualMemoryManager(unsigned long)+0x79
> V  [libjvm.so+0x182f84e] ZPageAllocator::ZPageAllocator(ZWorkers*, 
> unsigned long, unsigned long, unsigned long, unsigned long)+0x6e
> V  [libjvm.so+0x1808b61]  ZHeap::ZHeap()+0x81
> V  [libjvm.so+0x1802559] ZCollectedHeap::ZCollectedHeap()+0x49
>
> Thanks,
> StefanK



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