Changeset 220401 in webkit for trunk/Source/JavaScriptCore/ChangeLog

Timestamp:

Aug 8, 2017, 6:11:00 AM (8 years ago)

Author:

Yusuke Suzuki

Message:

[Linux] Clear WasmMemory with madvice instead of memset
​https://bugs.webkit.org/show_bug.cgi?id=175150

Reviewed by Filip Pizlo.

In Linux, zeroing pages with memset populates backing store.
Instead, we should use madvise with MADV_DONTNEED. It discards
pages. And if you access these pages, on-demand-zero-pages will
be shown.

We also commit grown pages in all OSes.

• wasm/WasmMemory.cpp:

(JSC::Wasm::commitZeroPages):
(JSC::Wasm::Memory::create):
(JSC::Wasm::Memory::grow):

File:

• trunk/Source/JavaScriptCore/ChangeLog (modified) (1 diff)

trunk/Source/JavaScriptCore/ChangeLog

@@ +1 @@
+2017-08-06  Yusuke Suzuki  <[email protected]>
+
+        [Linux] Clear WasmMemory with madvice instead of memset
+        https://bugs.webkit.org/show_bug.cgi?id=175150
+
+        Reviewed by Filip Pizlo.
+
+        In Linux, zeroing pages with memset populates backing store.
+        Instead, we should use madvise with MADV_DONTNEED. It discards
+        pages. And if you access these pages, on-demand-zero-pages will
+        be shown.
+
+        We also commit grown pages in all OSes.
+
+        * wasm/WasmMemory.cpp:
+        (JSC::Wasm::commitZeroPages):
+        (JSC::Wasm::Memory::create):
+        (JSC::Wasm::Memory::grow):
+
 2017-08-07  Robin Morisset  <[email protected]>