updated workstealing (0 -> C-1) in wakeup strategy

Tsung-Wei Huang · Tsung-Wei Huang · commit 875404c8dfc4 · 2019-04-20T10:15:33.000-05:00
diff --git a/taskflow/executor/workstealing.hpp b/taskflow/executor/workstealing.hpp
@@ -585,12 +585,10 @@ void WorkStealingExecutor<Closure>::_explore_task(
       // wasteful thief
       else if(vtm != thief) {
         size_t C = _workers[vtm].mailbox.load(std::memory_order_acquire);
-        if(C && _workers[vtm].mailbox.compare_exchange_strong(C, 0,
+        if(C && _workers[vtm].mailbox.compare_exchange_strong(C, C-1,
                                                               std::memory_order_seq_cst,
                                                               std::memory_order_relaxed)) {
-          for(size_t c=0; c<C; ++c) {
-            _notifier.notify(false); 
-          }
+          _notifier.notify(false); 
         }
       }
     }

Original file line number	Diff line number	Diff line change
`@@ -585,12 +585,10 @@ void WorkStealingExecutor<Closure>::_explore_task(`
`585`	`585`	`// wasteful thief`
`586`	`586`	`else if(vtm != thief) {`
`587`	`587`	`size_t C = _workers[vtm].mailbox.load(std::memory_order_acquire);`
`588`		`- if(C && _workers[vtm].mailbox.compare_exchange_strong(C, 0,`
	`588`	`+ if(C && _workers[vtm].mailbox.compare_exchange_strong(C, C-1,`
`589`	`589`	`std::memory_order_seq_cst,`
`590`	`590`	`std::memory_order_relaxed)) {`
`591`		`- for(size_t c=0; c<C; ++c) {`
`592`		`- _notifier.notify(false);`
`593`		`- }`
	`591`	`+ _notifier.notify(false);`
`594`	`592`	`}`
`595`	`593`	`}`
`596`	`594`	`}`