46 lines
1.4 KiB
Java
46 lines
1.4 KiB
Java
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// Copyright 2012 The Chromium Authors
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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package org.chromium.base;
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import org.jni_zero.JNINamespace;
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import org.jni_zero.NativeMethods;
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// The only purpose of this class is to allow sending CPU properties
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// from the browser process to sandboxed renderer processes. This is
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// needed because sandboxed processes cannot, on ARM, query the kernel
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// about the CPU's properties by parsing /proc, so this operation must
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// be performed in the browser process, and the result passed to
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// renderer ones.
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//
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// For more context, see http://crbug.com/164154
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//
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// Technically, this is a wrapper around the native NDK cpufeatures
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// library. The exact CPU features bits are never used in Java so
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// there is no point in duplicating their definitions here.
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//
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@JNINamespace("base::android")
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public abstract class CpuFeatures {
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/** Return the number of CPU Cores on the device. */
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public static int getCount() {
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return CpuFeaturesJni.get().getCoreCount();
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}
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/**
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* Return the CPU feature mask.
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* This is a 64-bit integer that corresponds to the CPU's features.
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* The value comes directly from android_getCpuFeatures().
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*/
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public static long getMask() {
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return CpuFeaturesJni.get().getCpuFeatures();
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}
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@NativeMethods
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interface Natives {
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int getCoreCount();
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long getCpuFeatures();
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}
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}
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