Changeset 211028 in webkit

Timestamp:

Jan 22, 2017, 10:51:09 AM (10 years ago)

Author:

dino@apple.com

Message:

[WebGL] Do not allow GPU muxing on some old Mac hardware
​https://bugs.webkit.org/show_bug.cgi?id=167259
<rdar://problem/30060378>

Reviewed by Simon Fraser and Darin Adler.

Some old Macbook Pro models should never use the
integrated GPU for WebGL, because they are unstable
when swapping between that and the discrete GPU.

Unfortunately this hardware configuration isn't in our
testing infrastructure, so it was confirmed manually.
Meanwhile, our existing tests make sure this patch
doesn't break anything elsewhere.

• platform/graphics/mac/GraphicsContext3DMac.mm:

(WebCore::attachToAppleGraphicsControl): Helper function
to get a mach port that talks to Apple's Graphics Control
system.
(WebCore::hasMuxCapability): Decides whether a system
can do live GPU switching, based on whether or not it
has a muxable GPU, and if that GPU is not the old hardware
we know is problematic.
(WebCore::hasMuxableGPU): Helper to return the static hasMuxCapability value.
(WebCore::setPixelFormat): Only request the integrated card when the
GPU is muxable.

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• platform/graphics/mac/GraphicsContext3DMac.mm (modified) (4 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2017-01-20  Dean Jackson  <dino@apple.com>
+
+        [WebGL] Do not allow GPU muxing on some old Mac hardware
+        https://bugs.webkit.org/show_bug.cgi?id=167259
+        <rdar://problem/30060378>
+
+        Reviewed by Simon Fraser and Darin Adler.
+
+        Some old Macbook Pro models should never use the
+        integrated GPU for WebGL, because they are unstable
+        when swapping between that and the discrete GPU.
+
+        Unfortunately this hardware configuration isn't in our
+        testing infrastructure, so it was confirmed manually.
+        Meanwhile, our existing tests make sure this patch
+        doesn't break anything elsewhere.
+
+        * platform/graphics/mac/GraphicsContext3DMac.mm:
+        (WebCore::attachToAppleGraphicsControl): Helper function
+        to get a mach port that talks to Apple's Graphics Control
+        system.
+        (WebCore::hasMuxCapability): Decides whether a system
+        can do live GPU switching, based on whether or not it
+        has a muxable GPU, and if that GPU is not the old hardware
+        we know is problematic.
+        (WebCore::hasMuxableGPU): Helper to return the static hasMuxCapability value.
+        (WebCore::setPixelFormat): Only request the integrated card when the
+        GPU is muxable.
+
 2017-01-22  Don Olmstead <don.olmstead@am.sony.com> and Myles C. Maxfield <mmaxfield@apple.com>
 

trunk/Source/WebCore/platform/graphics/mac/GraphicsContext3DMac.mm

@@ -42 +42 @@
 #include "ImageBuffer.h"
 #include "Logging.h"
+#include "WebGLLayer.h"
+#include "WebGLObject.h"
+#include "WebGLRenderingContextBase.h"
+#include <sys/sysctl.h>
+#include <sysexits.h>
+#include <wtf/text/CString.h>
+
 #if PLATFORM(IOS)
 #import "OpenGLESSPI.h"
@@ -49 +56 @@
 #import <QuartzCore/QuartzCore.h>
 #else
+#include <IOKit/IOKitLib.h>
 #include <OpenGL/CGLRenderers.h>
 #include <OpenGL/gl.h>
 #endif
-#include "WebGLLayer.h"
-#include "WebGLObject.h"
-#include "WebGLRenderingContextBase.h"
-#include <sysexits.h>
-#include <wtf/text/CString.h>
 
 namespace WebCore {
@@ -79 +82 @@
 };
 
-#if !PLATFORM(IOS)
+#if PLATFORM(MAC)
+
+enum {
+    kAGCOpen,
+    kAGCClose
+};
+
+static io_connect_t attachToAppleGraphicsControl()
+{
+    mach_port_t masterPort;
+
+    if (IOMasterPort(MACH_PORT_NULL, &masterPort) != KERN_SUCCESS)
+        return MACH_PORT_NULL;
+
+    CFDictionaryRef classToMatch = IOServiceMatching("AppleGraphicsControl");
+    if (!classToMatch)
+        return MACH_PORT_NULL;
+
+    kern_return_t kernResult;
+    io_iterator_t iterator;
+    if ((kernResult = IOServiceGetMatchingServices(masterPort, classToMatch, &iterator)) != KERN_SUCCESS)
+        return MACH_PORT_NULL;
+
+    io_service_t serviceObject = IOIteratorNext(iterator);
+    IOObjectRelease(iterator);
+    if (!serviceObject)
+        return MACH_PORT_NULL;
+
+    io_connect_t dataPort;
+    IOObjectRetain(serviceObject);
+    kernResult = IOServiceOpen(serviceObject, mach_task_self(), 0, &dataPort);
+    IOObjectRelease(serviceObject);
+
+    return (kernResult == KERN_SUCCESS) ? dataPort : MACH_PORT_NULL;
+}
+
+static bool hasMuxCapability()
+{
+    io_connect_t dataPort = attachToAppleGraphicsControl();
+
+    if (dataPort == MACH_PORT_NULL)
+        return false;
+
+    bool result;
+    if (IOConnectCallScalarMethod(dataPort, kAGCOpen, nullptr, 0, nullptr, nullptr) == KERN_SUCCESS) {
+        IOConnectCallScalarMethod(dataPort, kAGCClose, nullptr, 0, nullptr, nullptr);
+        result = true;
+    } else
+        result = false;
+
+    IOServiceClose(dataPort);
+
+    if (result) {
+        // This is detecting Mac hardware with an Intel g575 GPU, which
+        // we don't want to make available to muxing.
+        // Based on information from Apple's OpenGL team, such devices
+        // have four or fewer processors.
+        // <rdar://problem/30060378>
+        int names[2] = { CTL_HW, HW_NCPU };
+        int cpuCount;
+        size_t cpuCountLength = sizeof(cpuCount);
+        sysctl(names, 2, &cpuCount, &cpuCountLength, nullptr, 0);
+        result = cpuCount > 4;
+    }
+
+    return result;
+}
+
+static bool hasMuxableGPU()
+{
+    static bool canMux = hasMuxCapability();
+    return canMux;
+}
+
 static void setPixelFormat(Vector<CGLPixelFormatAttribute>& attribs, int colorBits, int depthBits, bool accelerated, bool supersample, bool closest, bool antialias, bool allowOffline, bool useGLES3)
 {
@@ -93 +169 @@
     // system, and not force the discrete GPU.
     // See https://developer.apple.com/library/mac/technotes/tn2229/_index.html
-    if (allowOffline)
+    if (allowOffline && hasMuxableGPU())
         attribs.append(kCGLPFAAllowOfflineRenderers);