Improve EMPER worker wakeup strategy option

Initiailze the WORKER_WAKEUP_STRATEGY via the contents of the
EMPER_WORKER_WAKEUP_STRATEGY macro. This makes it easier to add
additional strategies later on.

emper/Emper.hpp

@@ -23,14 +23,14 @@ static const bool WORKER_SLEEP =
 		false
 #endif
 		;
-enum class WorkerWakeupStrategy { one, all };
+
+enum class WorkerWakeupStrategy {
+	one,
+	all,
+};
+
 static const enum WorkerWakeupStrategy WORKER_WAKEUP_STRATEGY =
-#ifdef EMPER_WORKER_WAKEUP_ALL
-		WorkerWakeupStrategy::all
-#else
-		WorkerWakeupStrategy::one
-#endif
-		;
+		WorkerWakeupStrategy::EMPER_WORKER_WAKEUP_STRATEGY;
 
 static const bool LIBURCU =
 #ifdef EMPER_LIBURCU

emper/Runtime.hpp

@@ -7,8 +7,8 @@
 #include <atomic>							 // for atomic, memory_order_relaxed
 #include <cassert>						 // for assert
 #include <condition_variable>	 // for condition_variable
-#include <cstddef>						 // for size_t
 #include <cstdint>						 // for intptr_t
+#include <cstdlib>						 // for abort
 #include <functional>					 // for function
 #include <mutex>							 // for mutex, lock_guard, unique_lock
 #include <random>
@@ -90,9 +90,12 @@ class Runtime : public Logger<LogSubsystem::RUNTI> {
 		if constexpr (emper::WORKER_WAKEUP_STRATEGY == emper::WorkerWakeupStrategy::all) {
 			sleepingWorkers.store(0, std::memory_order_relaxed);
 			workerSleepConditionVariable.notify_all();
-		} else {
+		} else if (emper::WORKER_WAKEUP_STRATEGY == emper::WorkerWakeupStrategy::one) {
 			sleepingWorkers.fetch_sub(1, std::memory_order_relaxed);
 			workerSleepConditionVariable.notify_one();
+		} else {
+			// Unknown worker wakeup strategy.
+			abort();
 		}
 	}
 

meson.build

@@ -26,7 +26,7 @@ if option_urcu
 endif
 
 conf_data.set('EMPER_WORKER_SLEEP', get_option('worker_sleep'))
-conf_data.set('EMPER_WORKER_WAKEUP_ALL', get_option('worker_wakeup_strategy') == 'all')
+conf_data.set('EMPER_WORKER_WAKEUP_STRATEGY', get_option('worker_wakeup_strategy'))
 conf_data.set('EMPER_LOCKED_WS_QUEUE', get_option('locked_ws_queue'))
 conf_data.set('EMPER_OVERFLOW_QUEUE', get_option('overflow_queue'))
 conf_data.set('EMPER_LOCKED_MPSC_QUEUE', get_option('locked_mpsc_queue'))

meson_options.txt

@@ -19,7 +19,7 @@ option(
 option(
   'worker_wakeup_strategy',
   type: 'combo',
-  description: 'How many workers should be signaled onNewWork',
+  description: 'The strategy used to wakeup sleeping workers (only effective if worker_sleep is enabled)',
   choices: ['one', 'all'],
   value: 'one',
 )