On Fri, 30 Jul 2021 16:28:54 GMT, Thomas Stuefe <stu...@openjdk.org> wrote:
>> src/hotspot/share/services/nmtPreInit.hpp line 202: >> >>> 200: assert((*aa) != NULL, "Entry not found: " PTR_FORMAT, p2i(p)); >>> 201: NMTPreInitAllocation* a = (*aa); >>> 202: (*aa) = (*aa)->next; // remove from its list >> >> Could this be a race? There is no synchronization, read/write result could >> be arbitrary. > > The code is implicitly thread-safe because the hashmap is only modified in > the pre-NMT-init phase. After NMT initialization, the table is read-only. > During pre-NMT-init we are effectively single-threaded - at most two threads > access the map, the thread loading the libjvm, and the thread calling > CreateJavaVM, but not at the same time. > > See also the asserts in the AllStatic class `NMTPreInit`. > > (I should have described it more clearly, will add a comment.) So, you are saying that there is no memory that is malloc'd pre-NMT-init phase and freed post-NMT-init phase? ------------- PR: https://git.openjdk.java.net/jdk/pull/4874
