# HG changeset patch
# User shade
# Date 1557817926 -7200
# Node ID 76751d3faf7bdf3693cdf68f5d75378f1fd0ba62
# Parent  0eee5adb22d78989f05e6219fe5195b9f8d5f534
8223762: Shenandoah: overflows in calculations involving heap capacity
Reviewed-by: rkennke

diff -r 0eee5adb22d7 -r 76751d3faf7b src/hotspot/share/gc/shenandoah/heuristics/shenandoahAdaptiveHeuristics.cpp
--- a/src/hotspot/share/gc/shenandoah/heuristics/shenandoahAdaptiveHeuristics.cpp	Tue May 14 09:12:00 2019 +0200
+++ b/src/hotspot/share/gc/shenandoah/heuristics/shenandoahAdaptiveHeuristics.cpp	Tue May 14 09:12:06 2019 +0200
@@ -73,9 +73,9 @@
   // ShenandoahGarbageThreshold is the soft threshold which would be ignored until min_garbage is hit.
 
   size_t capacity    = ShenandoahHeap::heap()->max_capacity();
-  size_t free_target = ShenandoahMinFreeThreshold * capacity / 100;
+  size_t free_target = capacity / 100 * ShenandoahMinFreeThreshold;
   size_t min_garbage = free_target > actual_free ? (free_target - actual_free) : 0;
-  size_t max_cset    = (size_t)(1.0 * ShenandoahEvacReserve * capacity / 100 / ShenandoahEvacWaste);
+  size_t max_cset    = (size_t)((1.0 * capacity / 100 * ShenandoahEvacReserve) / ShenandoahEvacWaste);
 
   log_info(gc, ergo)("Adaptive CSet Selection. Target Free: " SIZE_FORMAT "M, Actual Free: "
                      SIZE_FORMAT "M, Max CSet: " SIZE_FORMAT "M, Min Garbage: " SIZE_FORMAT "M",
@@ -128,7 +128,7 @@
 
   // Check if we are falling below the worst limit, time to trigger the GC, regardless of
   // anything else.
-  size_t min_threshold = ShenandoahMinFreeThreshold * heap->max_capacity() / 100;
+  size_t min_threshold = capacity / 100 * ShenandoahMinFreeThreshold;
   if (available < min_threshold) {
     log_info(gc)("Trigger: Free (" SIZE_FORMAT "M) is below minimum threshold (" SIZE_FORMAT "M)",
                  available / M, min_threshold / M);
@@ -138,7 +138,7 @@
   // Check if are need to learn a bit about the application
   const size_t max_learn = ShenandoahLearningSteps;
   if (_gc_times_learned < max_learn) {
-    size_t init_threshold = ShenandoahInitFreeThreshold * heap->max_capacity() / 100;
+    size_t init_threshold = capacity / 100 * ShenandoahInitFreeThreshold;
     if (available < init_threshold) {
       log_info(gc)("Trigger: Learning " SIZE_FORMAT " of " SIZE_FORMAT ". Free (" SIZE_FORMAT "M) is below initial threshold (" SIZE_FORMAT "M)",
                    _gc_times_learned + 1, max_learn, available / M, init_threshold / M);
@@ -152,8 +152,8 @@
 
   size_t allocation_headroom = available;
 
-  size_t spike_headroom = ShenandoahAllocSpikeFactor * capacity / 100;
-  size_t penalties      = _gc_time_penalties         * capacity / 100;
+  size_t spike_headroom = capacity / 100 * ShenandoahAllocSpikeFactor;
+  size_t penalties      = capacity / 100 * _gc_time_penalties;
 
   allocation_headroom -= MIN2(allocation_headroom, spike_headroom);
   allocation_headroom -= MIN2(allocation_headroom, penalties);
diff -r 0eee5adb22d7 -r 76751d3faf7b src/hotspot/share/gc/shenandoah/heuristics/shenandoahCompactHeuristics.cpp
--- a/src/hotspot/share/gc/shenandoah/heuristics/shenandoahCompactHeuristics.cpp	Tue May 14 09:12:00 2019 +0200
+++ b/src/hotspot/share/gc/shenandoah/heuristics/shenandoahCompactHeuristics.cpp	Tue May 14 09:12:06 2019 +0200
@@ -52,9 +52,11 @@
 bool ShenandoahCompactHeuristics::should_start_normal_gc() const {
   ShenandoahHeap* heap = ShenandoahHeap::heap();
 
+  size_t capacity = heap->max_capacity();
   size_t available = heap->free_set()->available();
-  size_t threshold_bytes_allocated = heap->max_capacity() * ShenandoahAllocationThreshold / 100;
-  size_t min_threshold = ShenandoahMinFreeThreshold * heap->max_capacity() / 100;
+
+  size_t threshold_bytes_allocated = capacity / 100 * ShenandoahAllocationThreshold;
+  size_t min_threshold = capacity / 100 * ShenandoahMinFreeThreshold;
 
   if (available < min_threshold) {
     log_info(gc)("Trigger: Free (" SIZE_FORMAT "M) is below minimum threshold (" SIZE_FORMAT "M)",
diff -r 0eee5adb22d7 -r 76751d3faf7b src/hotspot/share/gc/shenandoah/heuristics/shenandoahPassiveHeuristics.cpp
--- a/src/hotspot/share/gc/shenandoah/heuristics/shenandoahPassiveHeuristics.cpp	Tue May 14 09:12:00 2019 +0200
+++ b/src/hotspot/share/gc/shenandoah/heuristics/shenandoahPassiveHeuristics.cpp	Tue May 14 09:12:06 2019 +0200
@@ -82,7 +82,7 @@
   // Do not select too large CSet that would overflow the available free space.
   // Take at least the entire evacuation reserve, and be free to overflow to free space.
   size_t capacity  = ShenandoahHeap::heap()->max_capacity();
-  size_t available = MAX2(ShenandoahEvacReserve * capacity / 100, actual_free);
+  size_t available = MAX2(capacity / 100 * ShenandoahEvacReserve, actual_free);
   size_t max_cset  = (size_t)(available / ShenandoahEvacWaste);
 
   log_info(gc, ergo)("CSet Selection. Actual Free: " SIZE_FORMAT "M, Max CSet: " SIZE_FORMAT "M",
diff -r 0eee5adb22d7 -r 76751d3faf7b src/hotspot/share/gc/shenandoah/heuristics/shenandoahStaticHeuristics.cpp
--- a/src/hotspot/share/gc/shenandoah/heuristics/shenandoahStaticHeuristics.cpp	Tue May 14 09:12:00 2019 +0200
+++ b/src/hotspot/share/gc/shenandoah/heuristics/shenandoahStaticHeuristics.cpp	Tue May 14 09:12:06 2019 +0200
@@ -54,7 +54,7 @@
 
   size_t capacity = heap->max_capacity();
   size_t available = heap->free_set()->available();
-  size_t threshold_available = (capacity * ShenandoahFreeThreshold) / 100;
+  size_t threshold_available = capacity / 100 * ShenandoahFreeThreshold;
 
   if (available < threshold_available) {
     log_info(gc)("Trigger: Free (" SIZE_FORMAT "M) is below free threshold (" SIZE_FORMAT "M)",
diff -r 0eee5adb22d7 -r 76751d3faf7b src/hotspot/share/gc/shenandoah/heuristics/shenandoahTraversalHeuristics.cpp
--- a/src/hotspot/share/gc/shenandoah/heuristics/shenandoahTraversalHeuristics.cpp	Tue May 14 09:12:00 2019 +0200
+++ b/src/hotspot/share/gc/shenandoah/heuristics/shenandoahTraversalHeuristics.cpp	Tue May 14 09:12:06 2019 +0200
@@ -119,9 +119,9 @@
 
   size_t capacity    = heap->max_capacity();
   size_t actual_free = heap->free_set()->available();
-  size_t free_target = ShenandoahMinFreeThreshold * capacity / 100;
+  size_t free_target = capacity / 100 * ShenandoahMinFreeThreshold;
   size_t min_garbage = free_target > actual_free ? (free_target - actual_free) : 0;
-  size_t max_cset    = (size_t)(1.0 * ShenandoahEvacReserve * capacity / 100 / ShenandoahEvacWaste);
+  size_t max_cset    = (size_t)((1.0 * capacity / 100 * ShenandoahEvacReserve) / ShenandoahEvacWaste);
 
   log_info(gc, ergo)("Adaptive CSet Selection. Target Free: " SIZE_FORMAT "M, Actual Free: "
                      SIZE_FORMAT "M, Max CSet: " SIZE_FORMAT "M, Min Garbage: " SIZE_FORMAT "M",
@@ -211,7 +211,7 @@
 
   // Check if we are falling below the worst limit, time to trigger the GC, regardless of
   // anything else.
-  size_t min_threshold = ShenandoahMinFreeThreshold * heap->max_capacity() / 100;
+  size_t min_threshold = capacity / 100 * ShenandoahMinFreeThreshold;
   if (available < min_threshold) {
     log_info(gc)("Trigger: Free (" SIZE_FORMAT "M) is below minimum threshold (" SIZE_FORMAT "M)",
                  available / M, min_threshold / M);
@@ -221,7 +221,7 @@
   // Check if are need to learn a bit about the application
   const size_t max_learn = ShenandoahLearningSteps;
   if (_gc_times_learned < max_learn) {
-    size_t init_threshold = ShenandoahInitFreeThreshold * heap->max_capacity() / 100;
+    size_t init_threshold = capacity / 100 * ShenandoahInitFreeThreshold;
     if (available < init_threshold) {
       log_info(gc)("Trigger: Learning " SIZE_FORMAT " of " SIZE_FORMAT ". Free (" SIZE_FORMAT "M) is below initial threshold (" SIZE_FORMAT "M)",
                    _gc_times_learned + 1, max_learn, available / M, init_threshold / M);
@@ -235,8 +235,8 @@
 
   size_t allocation_headroom = available;
 
-  size_t spike_headroom = ShenandoahAllocSpikeFactor * capacity / 100;
-  size_t penalties      = _gc_time_penalties         * capacity / 100;
+  size_t spike_headroom = capacity / 100 * ShenandoahAllocSpikeFactor;
+  size_t penalties      = capacity / 100 * _gc_time_penalties;
 
   allocation_headroom -= MIN2(allocation_headroom, spike_headroom);
   allocation_headroom -= MIN2(allocation_headroom, penalties);
diff -r 0eee5adb22d7 -r 76751d3faf7b src/hotspot/share/gc/shenandoah/shenandoahFreeSet.cpp
--- a/src/hotspot/share/gc/shenandoah/shenandoahFreeSet.cpp	Tue May 14 09:12:00 2019 +0200
+++ b/src/hotspot/share/gc/shenandoah/shenandoahFreeSet.cpp	Tue May 14 09:12:06 2019 +0200
@@ -430,7 +430,7 @@
   }
 
   // Evac reserve: reserve trailing space for evacuations
-  size_t to_reserve = ShenandoahEvacReserve * _heap->max_capacity() / 100;
+  size_t to_reserve = _heap->max_capacity() / 100 * ShenandoahEvacReserve;
   size_t reserved = 0;
 
   for (size_t idx = _heap->num_regions() - 1; idx > 0; idx--) {
diff -r 0eee5adb22d7 -r 76751d3faf7b src/hotspot/share/gc/shenandoah/shenandoahPacer.cpp
--- a/src/hotspot/share/gc/shenandoah/shenandoahPacer.cpp	Tue May 14 09:12:00 2019 +0200
+++ b/src/hotspot/share/gc/shenandoah/shenandoahPacer.cpp	Tue May 14 09:12:06 2019 +0200
@@ -153,7 +153,7 @@
 void ShenandoahPacer::setup_for_idle() {
   assert(ShenandoahPacing, "Only be here when pacing is enabled");
 
-  size_t initial = _heap->max_capacity() * ShenandoahPacingIdleSlack / 100;
+  size_t initial = _heap->max_capacity() / 100 * ShenandoahPacingIdleSlack;
   double tax = 1;
 
   restart_with(initial, tax);