On Thu, 18 Feb 2021 07:59:45 GMT, Andrey Turbanov <github.com+741251+turban...@openjdk.org> wrote:
>> Hello @turbanoff, the double read is necessary to correctly avoid any race >> conditions and is a typical strategy used in cases like these. I am not >> aware of any other alternate more performant strategy, for code like this. > > Let me be more clear: I think that it's enough to have only 2 `volatile` > field reads _in worst case_. We can use local variable to avoid more than > needed reads. > Current code can perform read 4 times _in worst case_: twice outside > `synchronized` block and twice inside `synchronized` block. > > There are many examples of similar code in the JDK: > https://github.com/openjdk/jdk/blob/master/src/jdk.crypto.cryptoki/share/classes/sun/security/pkcs11/P11Util.java#L48 > https://github.com/openjdk/jdk/blob/master/src/java.base/share/classes/java/lang/StackFrameInfo.java#L125 Ah! of course, I now see what you mean. I misunderstood your previous comment. I'll update this PR shortly. ------------- PR: https://git.openjdk.java.net/jdk/pull/2601
