On Thu, 22 Aug 2024 19:50:01 GMT, Alex Menkov <amen...@openjdk.org> wrote:
> On Windows SA agent gets a class vtable from symbols, exported from jvm.dll > (it exports symbols like "??_7" + type + "@@6B@"). > But symbol lookup function first requests WinDbg about the symbol. > Sometimes WinDbg routine IDebugSymbols::GetOffsetByName() returns offset for > both class and class pointer types. Returned offsets correspond to symbols > like "jvm!class_name::`vftable'". > The behavior is intermittent, I was not able to find what is the reason. > The fix adds workaround for the case - if GetOffsetByName succeeded, we check > if corresponding symbol contains requested one. > So it returns expected offset for non-vtable symbols like > "MaxJNILocalCapacity" (GetOffsetByName returns offset for > "jvm!MaxJNILocalCapacity"), but returns 0 for vtlb lookup. > > Additionally added check for results of > IDebugSymbols::SetImagePath/SetSymbolPath > > Testing: tier1,tier2,hs-tier5-svc Why do we rely on GetOffsetByName() when we can already lookup directly from the dll, and this is in fact the fallback already in place when GetOffsetByName() fails? ------------- PR Comment: https://git.openjdk.org/jdk/pull/20684#issuecomment-2310645991
