Fix Titzer bench on iOS.

kmiller68 · kmiller68 · commit 1920b51c499c · 2017-08-24T02:11:02.000Z
https://bugs.webkit.org/show_bug.cgi?id=175917 Reviewed by Ryosuke Niwa. Currently, Titzer bench doesn't run on iOS since the benchmark allocates lots of physical pages that it never actually writes to. We limited the total number wasm physical pages to the ram size of the phone, which caused us to fail a memory allocation. This patch changes it so we will allocate up to 3x ram size, which seems to fix the problem. * wasm/WasmMemory.cpp: Canonical link: https://commits.webkit.org/192578@main git-svn-id: https://svn.webkit.org/repository/webkit/trunk@221126 268f45cc-cd09-0410-ab3c-d52691b4dbfc
diff --git a/Source/JavaScriptCore/ChangeLog b/Source/JavaScriptCore/ChangeLog
@@ -1,3 +1,19 @@
+2017-08-23  Keith Miller  <keith_miller@apple.com>
+
+        Fix Titzer bench on iOS.
+        https://bugs.webkit.org/show_bug.cgi?id=175917
+
+        Reviewed by Ryosuke Niwa.
+
+        Currently, Titzer bench doesn't run on iOS since the benchmark
+        allocates lots of physical pages that it never actually writes
+        to. We limited the total number wasm physical pages to the ram
+        size of the phone, which caused us to fail a memory
+        allocation. This patch changes it so we will allocate up to 3x ram
+        size, which seems to fix the problem.
+
+        * wasm/WasmMemory.cpp:
+
 2017-08-23  Yusuke Suzuki  <utatane.tea@gmail.com>
 
         Unreviewed, fix for test262
diff --git a/Source/JavaScriptCore/wasm/WasmMemory.cpp b/Source/JavaScriptCore/wasm/WasmMemory.cpp
@@ -140,19 +140,24 @@ class MemoryManager {
         }
         return false;
     }
-    
+
+    // We allow people to "commit" more wasm memory than there is on the system since most of the time
+    // people don't actually write to most of that memory. There is some chance that this gets us
+    // JetSammed but that's possible anyway.
+    inline size_t memoryLimit() const { return ramSize() * 3; }
+
     // FIXME: Ideally, bmalloc would have this kind of mechanism. Then, we would just forward to that
     // mechanism here.
     MemoryResult::Kind tryAllocatePhysicalBytes(size_t bytes)
     {
         MemoryResult::Kind result = [&] {
             auto holder = holdLock(m_lock);
-            if (m_physicalBytes + bytes > ramSize())
+            if (m_physicalBytes + bytes > memoryLimit())
                 return MemoryResult::SyncGCAndRetry;
             
             m_physicalBytes += bytes;
             
-            if (m_physicalBytes >= ramSize() / 2)
+            if (m_physicalBytes >= memoryLimit() / 2)
                 return MemoryResult::SuccessAndAsyncGC;
             
             return MemoryResult::Success;
@@ -177,7 +182,7 @@ class MemoryManager {
     
     void dump(PrintStream& out) const
     {
-        out.print("memories =  ", m_memories.size(), "/", m_maxCount, ", bytes = ", m_physicalBytes, "/", ramSize());
+        out.print("virtual memories =  ", m_memories.size(), "/", m_maxCount, ", bytes = ", m_physicalBytes, "/", memoryLimit());
     }
     
 private:
