On Sun, 17 Nov 2024 15:33:02 GMT, Doug Lea <d...@openjdk.org> wrote:
>> This addresses tendencies in previous update to increase fencing, scanning,
>> and signalling that can increase contention, and slow down performance
>> especially on ARM platforms. It also uses more ARM-friendly constructions to
>> reduce overhead (leading to several changes that all of the same form),
>
> Doug Lea has updated the pull request incrementally with one additional
> commit since the last revision:
>
> Ensure InnocuousForkJoinWorkerThread usable with or without SecurityManager
src/java.base/share/classes/java/util/concurrent/ForkJoinPool.java line 2780:
> 2778: now = true;
> 2779: }
> 2780: if (now) {
@DougLea I'd probably add a blank line above this one to signal that this if is
not a part of the previous if-else chain.
src/java.base/share/classes/java/util/concurrent/ForkJoinPool.java line 2805:
> 2803: }
> 2804: }
> 2805: return e;
@DougLea Is there any benefit to using `break` in the loop rather than `return
e;` directly?
src/java.base/share/classes/java/util/concurrent/ForkJoinPool.java line 2838:
> 2836: }
> 2837: }
> 2838: else if ((q.phase & (IDLE|1)) == 0 ||
@DougLea What's the intent of the `|1` part here? 🤔
src/java.base/share/classes/java/util/concurrent/ForkJoinPool.java line 4082:
> 4080: AccessController.doPrivileged(new PrivilegedAction<>() {
> 4081: public ForkJoinPool run() {
> 4082: return new ForkJoinPool((byte)0); }});
@AlanBateman Any recommendation as to what is ideal here with SM removed? /cc
@DougLea
src/java.base/share/classes/java/util/concurrent/ForkJoinWorkerThread.java line
247:
> 245: = U.objectFieldOffset(Thread.class, "threadLocals");
> 246: private static final long INHERITABLETHREADLOCALS
> 247: = U.objectFieldOffset(Thread.class, "inheritableThreadLocals");
@AlanBateman Thoughts here? 🤔
src/java.base/share/classes/java/util/concurrent/ForkJoinWorkerThread.java line
270:
> 268: @SuppressWarnings("removal")
> 269: public void setContextClassLoader(ClassLoader cl) {
> 270: if (System.getSecurityManager() != null &&
@AlanBateman Alternatives for this? 🤔
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/21507#discussion_r1848717378
PR Review Comment: https://git.openjdk.org/jdk/pull/21507#discussion_r1848720748
PR Review Comment: https://git.openjdk.org/jdk/pull/21507#discussion_r1848722786
PR Review Comment: https://git.openjdk.org/jdk/pull/21507#discussion_r1848724803
PR Review Comment: https://git.openjdk.org/jdk/pull/21507#discussion_r1848727422
PR Review Comment: https://git.openjdk.org/jdk/pull/21507#discussion_r1848728622
