From 7f6fb152cb68b30c4d38b9f69298eb6aec96278a Mon Sep 17 00:00:00 2001
From: Florian Fischer <florian.fischer@muhq.space>
Date: Sat, 22 Jan 2022 12:27:25 +0100
Subject: [PATCH] [meson] add option to ignore wakeup hints
I think wakeup hints should never be ignored but having the option
seams usefull to observe their benefits/cost.
---
emper/Emper.hpp | 8 ++++++++
emper/strategies/AbstractWorkStealingScheduler.cpp | 5 +++++
meson.build | 1 +
meson_options.txt | 6 ++++++
4 files changed, 20 insertions(+)
diff --git a/emper/Emper.hpp b/emper/Emper.hpp
index bffad3df..668660c8 100644
--- a/emper/Emper.hpp
+++ b/emper/Emper.hpp
@@ -61,6 +61,14 @@ enum class WorkerWakeupStrategy {
static const enum WorkerWakeupStrategy WORKER_WAKEUP_STRATEGY =
WorkerWakeupStrategy::EMPER_WORKER_WAKEUP_STRATEGY;
+static const bool WORKER_IGNORE_WAKEUP_HINT =
+#ifdef EMPER_WORKER_IGNORE_WAKEUP_HINT
+ true
+#else
+ false
+#endif
+ ;
+
static const bool LIBURCU =
#ifdef EMPER_LIBURCU
true
diff --git a/emper/strategies/AbstractWorkStealingScheduler.cpp b/emper/strategies/AbstractWorkStealingScheduler.cpp
index 028dd892..2814a417 100644
--- a/emper/strategies/AbstractWorkStealingScheduler.cpp
+++ b/emper/strategies/AbstractWorkStealingScheduler.cpp
@@ -184,6 +184,10 @@ popBottom:
auto* const currentWorker = Worker::getCurrentWorker();
+ if constexpr (emper::WORKER_IGNORE_WAKEUP_HINT) {
+ goto work_stealing;
+ }
+
// Try dispatch hint possibly set by the sleep strategy
if (currentWorker->dispatchHint) {
const emper::FiberHint dispatchHint = currentWorker->dispatchHint;
@@ -214,6 +218,7 @@ popBottom:
}
}
+work_stealing:
// Go into work stealing
// TODO: Determine if there is a better value than 1/3.
const float CHECK_ANYWHERE_QUEUE_AT_PERCENTAGE = 0.33;
diff --git a/meson.build b/meson.build
index 80b1df3f..71cb6c4a 100644
--- a/meson.build
+++ b/meson.build
@@ -49,6 +49,7 @@ endif
conf_data.set('EMPER_WORKER_SLEEP', get_option('worker_sleep'))
conf_data.set('EMPER_WORKER_WAKEUP_STRATEGY', get_option('worker_wakeup_strategy'))
+conf_data.set('EMPER_WORKER_IGNORE_WAKEUP_HINT', get_option('worker_ignore_wakeup_hint'))
conf_data.set('EMPER_LOCKED_WS_QUEUE', get_option('locked_ws_queue'))
conf_data.set('EMPER_LOCKED_MPSC_QUEUE', get_option('locked_mpsc_queue'))
conf_data.set('EMPER_OVERFLOW_QUEUE', get_option('overflow_queue'))
diff --git a/meson_options.txt b/meson_options.txt
index 115a5e55..1b54e3de 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -65,6 +65,12 @@ option(
value: 'posix',
description: 'Semaphore implementation to suspend/wakeup workers',
)
+option(
+ 'worker_ignore_wakeup_hint',
+ type: 'boolean',
+ description: 'Should possibly passed hints where to find new work be ignored',
+ value: false,
+)
option(
'locked_ws_queue',
type: 'boolean',
--
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