From f5bdae2d0cfabf50210ba030febfac2fba8aa333 Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jackpot51@gmail.com>
Date: Wed, 7 Sep 2022 18:21:30 -0600
Subject: [PATCH] Reduce schreduler time slices to reduce latency

---
 src/arch/aarch64/interrupt/irq.rs | 3 ++-
 src/arch/x86/interrupt/ipi.rs     | 3 ++-
 src/arch/x86/interrupt/irq.rs     | 3 ++-
 src/arch/x86_64/interrupt/ipi.rs  | 3 ++-
 src/arch/x86_64/interrupt/irq.rs  | 3 ++-
 5 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/src/arch/aarch64/interrupt/irq.rs b/src/arch/aarch64/interrupt/irq.rs
index 21e5c4a..7501836 100644
--- a/src/arch/aarch64/interrupt/irq.rs
+++ b/src/arch/aarch64/interrupt/irq.rs
@@ -59,7 +59,8 @@ pub unsafe fn irq_handler_gentimer(irq: u32) {
 
     timeout::trigger();
 
-    if PIT_TICKS.fetch_add(1, Ordering::SeqCst) >= 10 {
+    // Switch after 3 ticks (about 6.75 ms)
+    if PIT_TICKS.fetch_add(1, Ordering::SeqCst) >= 2 {
         let _ = context::switch();
     }
     trigger(irq);
diff --git a/src/arch/x86/interrupt/ipi.rs b/src/arch/x86/interrupt/ipi.rs
index 52aad2a..fd70507 100644
--- a/src/arch/x86/interrupt/ipi.rs
+++ b/src/arch/x86/interrupt/ipi.rs
@@ -24,7 +24,8 @@ interrupt!(switch, || {
 interrupt!(pit, || {
     LOCAL_APIC.eoi();
 
-    if PIT_TICKS.fetch_add(1, Ordering::SeqCst) >= 10 {
+    // Switch after 3 ticks (about 6.75 ms)
+    if PIT_TICKS.fetch_add(1, Ordering::SeqCst) >= 2 {
         let _ = context::switch();
     }
 });
diff --git a/src/arch/x86/interrupt/irq.rs b/src/arch/x86/interrupt/irq.rs
index c36844a..497053f 100644
--- a/src/arch/x86/interrupt/irq.rs
+++ b/src/arch/x86/interrupt/irq.rs
@@ -189,7 +189,8 @@ interrupt_stack!(pit_stack, |_stack| {
     // Any better way of doing this?
     timeout::trigger();
 
-    if PIT_TICKS.fetch_add(1, Ordering::SeqCst) >= 10 {
+    // Switch after 3 ticks (about 6.75 ms)
+    if PIT_TICKS.fetch_add(1, Ordering::SeqCst) >= 2 {
         let _ = context::switch();
     }
 });
diff --git a/src/arch/x86_64/interrupt/ipi.rs b/src/arch/x86_64/interrupt/ipi.rs
index 52aad2a..fd70507 100644
--- a/src/arch/x86_64/interrupt/ipi.rs
+++ b/src/arch/x86_64/interrupt/ipi.rs
@@ -24,7 +24,8 @@ interrupt!(switch, || {
 interrupt!(pit, || {
     LOCAL_APIC.eoi();
 
-    if PIT_TICKS.fetch_add(1, Ordering::SeqCst) >= 10 {
+    // Switch after 3 ticks (about 6.75 ms)
+    if PIT_TICKS.fetch_add(1, Ordering::SeqCst) >= 2 {
         let _ = context::switch();
     }
 });
diff --git a/src/arch/x86_64/interrupt/irq.rs b/src/arch/x86_64/interrupt/irq.rs
index c36844a..497053f 100644
--- a/src/arch/x86_64/interrupt/irq.rs
+++ b/src/arch/x86_64/interrupt/irq.rs
@@ -189,7 +189,8 @@ interrupt_stack!(pit_stack, |_stack| {
     // Any better way of doing this?
     timeout::trigger();
 
-    if PIT_TICKS.fetch_add(1, Ordering::SeqCst) >= 10 {
+    // Switch after 3 ticks (about 6.75 ms)
+    if PIT_TICKS.fetch_add(1, Ordering::SeqCst) >= 2 {
         let _ = context::switch();
     }
 });