Changeset 341aa39 for libcfa/src

Timestamp:

Apr 20, 2021, 5:19:07 PM (4 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

ADT, arm-eh, ast-experimental, enum, forall-pointer-decay, jacob/cs343-translation, master, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

c41c2dbe

Parents:

0583b47b

Message:

Fix bugs in workstealing edge cases:

• cutoff was wrong of all local queues are empty
• target would get stuck if the rng returned the local queues

File:

• libcfa/src/concurrency/ready_queue.cfa (modified) (1 diff)

libcfa/src/concurrency/ready_queue.cfa

@@ -417 +417 @@
                         unsigned long long tsc2 = ts(lanes.data[idx2]);
                         proc->rdq.cutoff = min(tsc1, tsc2);
-                }
-                else if(lanes.tscs[proc->rdq.target].tv < proc->rdq.cutoff) {
-                        $thread * t = try_pop(cltr, proc->rdq.target __STATS(, __tls_stats()->ready.pop.help));
+                        if(proc->rdq.cutoff == 0) proc->rdq.cutoff = -1ull;
+                }
+                else {
+                        unsigned target = proc->rdq.target;
                         proc->rdq.target = -1u;
-                        if(t) return t;
+                        if(lanes.tscs[target].tv < proc->rdq.cutoff) {
+                                $thread * t = try_pop(cltr, target __STATS(, __tls_stats()->ready.pop.help));
+                                if(t) return t;
+                        }
                 }