Changeset 277346 in webkit

Timestamp:

May 11, 2021, 5:52:09 PM (5 years ago)

Author:

ggaren@apple.com

Message:

ConservativeRoots triggers page demand on Speedometer
​https://bugs.webkit.org/show_bug.cgi?id=225676

Reviewed by Saam Barati.

Use a Vector instead of OSAllocator to avoid mmap() and page fault --
and, like, come on.

Bump default inlineCapacity up to 1024 because we seem to overflow
frequently.

• heap/ConservativeRoots.cpp:

(JSC::ConservativeRoots::ConservativeRoots):
(JSC::ConservativeRoots::~ConservativeRoots):
(JSC::ConservativeRoots::genericAddPointer):
(JSC::ConservativeRoots::grow): Deleted.

• heap/ConservativeRoots.h:

(JSC::ConservativeRoots::roots const):
(JSC::ConservativeRoots::size const): Deleted.

• heap/SlotVisitor.cpp:

(JSC::SlotVisitor::append):

• heap/VerifierSlotVisitor.cpp:

(JSC::VerifierSlotVisitor::append):

Location:

trunk/Source/JavaScriptCore

Files:

• ChangeLog (modified) (1 diff)
• heap/ConservativeRoots.cpp (modified) (3 diffs)
• heap/ConservativeRoots.h (modified) (3 diffs)
• heap/SlotVisitor.cpp (modified) (1 diff)
• heap/VerifierSlotVisitor.cpp (modified) (1 diff)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2021-05-11  Geoffrey Garen  <ggaren@apple.com>
+
+        ConservativeRoots triggers page demand on Speedometer
+        https://bugs.webkit.org/show_bug.cgi?id=225676
+
+        Reviewed by Saam Barati.
+
+        Use a Vector instead of OSAllocator to avoid mmap() and page fault --
+        and, like, come on.
+
+        Bump default inlineCapacity up to 1024 because we seem to overflow
+        frequently.
+
+        * heap/ConservativeRoots.cpp:
+        (JSC::ConservativeRoots::ConservativeRoots):
+        (JSC::ConservativeRoots::~ConservativeRoots):
+        (JSC::ConservativeRoots::genericAddPointer):
+        (JSC::ConservativeRoots::grow): Deleted.
+        * heap/ConservativeRoots.h:
+        (JSC::ConservativeRoots::roots const):
+        (JSC::ConservativeRoots::size const): Deleted.
+        * heap/SlotVisitor.cpp:
+        (JSC::SlotVisitor::append):
+        * heap/VerifierSlotVisitor.cpp:
+        (JSC::VerifierSlotVisitor::append):
+
 2021-05-10  Filip Pizlo  <fpizlo@apple.com>
 

trunk/Source/JavaScriptCore/heap/ConservativeRoots.cpp

@@ -39 +39 @@
 
 ConservativeRoots::ConservativeRoots(Heap& heap)
-    : m_roots(m_inlineRoots)
-    , m_size(0)
-    , m_capacity(inlineCapacity)
-    , m_heap(heap)
+    : m_heap(heap)
 {
 }
@@ -48 +45 @@
 ConservativeRoots::~ConservativeRoots()
 {
-    if (m_roots != m_inlineRoots)
-        OSAllocator::decommitAndRelease(m_roots, m_capacity * sizeof(HeapCell*));
-}
-
-void ConservativeRoots::grow()
-{
-    size_t newCapacity = m_capacity == inlineCapacity ? nonInlineCapacity : m_capacity * 2;
-    HeapCell** newRoots = static_cast<HeapCell**>(OSAllocator::reserveAndCommit(newCapacity * sizeof(HeapCell*)));
-    memcpy(newRoots, m_roots, m_size * sizeof(HeapCell*));
-    if (m_roots != m_inlineRoots)
-        OSAllocator::decommitAndRelease(m_roots, m_capacity * sizeof(HeapCell*));
-    m_capacity = newCapacity;
-    m_roots = newRoots;
 }
 
@@ -75 +59 @@
                 markHook.markKnownJSCell(static_cast<JSCell*>(p));
             
-            if (m_size == m_capacity)
-                grow();
-            
-            m_roots[m_size++] = bitwise_cast<HeapCell*>(p);
+            m_roots.append(bitwise_cast<HeapCell*>(p));
         });
 }

trunk/Source/JavaScriptCore/heap/ConservativeRoots.h

@@ -35 +35 @@
 
 class ConservativeRoots {
+    static constexpr size_t inlineCapacity = 1024;
+    
 public:
     ConservativeRoots(Heap&);
@@ -42 +44 @@
     void add(void* begin, void* end, JITStubRoutineSet&, CodeBlockSet&);
     
-    size_t size() const;
-    HeapCell** roots() const;
+    const Vector<HeapCell*, inlineCapacity>& roots() const { return m_roots; };
 
 private:
-    static constexpr size_t inlineCapacity = 128;
-    static constexpr size_t nonInlineCapacity = 8192 / sizeof(HeapCell*);
-    
     template<typename MarkHook>
     void genericAddPointer(void*, HeapVersion markingVersion, HeapVersion newlyAllocatedVersion, TinyBloomFilter, MarkHook&);
@@ -55 +53 @@
     void genericAddSpan(void*, void* end, MarkHook&);
     
-    void grow();
-
-    HeapCell** m_roots;
-    size_t m_size;
-    size_t m_capacity;
     Heap& m_heap;
-    HeapCell* m_inlineRoots[inlineCapacity];
+    Vector<HeapCell*, inlineCapacity> m_roots;
 };
 
-inline size_t ConservativeRoots::size() const
-{
-    return m_size;
-}
-
-inline HeapCell** ConservativeRoots::roots() const
-{
-    return m_roots;
-}
-
 } // namespace JSC

trunk/Source/JavaScriptCore/heap/SlotVisitor.cpp

@@ -130 +130 @@
 void SlotVisitor::append(const ConservativeRoots& conservativeRoots)
 {
-    HeapCell** roots = conservativeRoots.roots();
-    size_t size = conservativeRoots.size();
-    for (size_t i = 0; i < size; ++i)
-        appendJSCellOrAuxiliary(roots[i]);
+    for (auto root : conservativeRoots.roots())
+        appendJSCellOrAuxiliary(root);
 }
 

trunk/Source/JavaScriptCore/heap/VerifierSlotVisitor.cpp

@@ -149 +149 @@
     };
 
-    HeapCell** roots = conservativeRoots.roots();
-    size_t size = conservativeRoots.size();
-    for (size_t i = 0; i < size; ++i)
-        appendJSCellOrAuxiliary(roots[i]);
+    for (auto root : conservativeRoots.roots())
+        appendJSCellOrAuxiliary(root);
 }