MP Control 模块boost功能

高通平台有自己的performance 模块, 常见的场景是加速响应用户的触控响应.
主要分为java 应用层,Native 层, 和私有库,以及Kernel的支持.

1. java层的应用场景.
   frameworks/base/core/java/android/app/Activity.java
   里面有对touch screen

    /** * Called to process touch screen events. You can override this to * intercept all touch screen events before they are dispatched to the * window. Be sure to call this implementation for touch screen events * that should be handled normally. * * @param ev The touch screen event. * * @return boolean Return true if this event was consumed. */
    public boolean dispatchTouchEvent(MotionEvent ev) {

        if(mDragBoostPossible == -1) {
            mDragBoostPossible = 0;
            String currentActivity = getPackageName();
            String[] activityList = getResources().getStringArray(
                com.android.internal.R.array.boost_activityList);
            if(activityList != null){
                for (String match : activityList) {
                    if (currentActivity.indexOf(match) != -1){
                        mDragBoostPossible = 1;
                        break;
                    }
                }
            }
        }
        if (mDragBoostPossible == 1) {
            if (mPerf == null){
                mPerf = new Performance();
            }
            if(mPerfLockDuration == -1){
                mPerfLockDuration = getResources().getInteger(
                    com.android.internal.R.integer.ascrollboost_timeout);
                mAsCpuBoost = getResources().getInteger(
                    com.android.internal.R.integer.ascrollboost_cpuboost);
                mAsSchedBoost = getResources().getInteger(
                    com.android.internal.R.integer.ascrollboost_schedboost);
                mAsPcDisblBoost = getResources().getInteger(
                    com.android.internal.R.integer.ascrollboost_pcdisbl);
            }
            mPerf.perfLockAcquireTouch(ev,
                getResources().getDisplayMetrics(),
                mPerfLockDuration,
                mAsSchedBoost, mAsCpuBoost, mAsPcDisblBoost);
        }
        if (ev.getAction() == MotionEvent.ACTION_DOWN) {
            onUserInteraction();
        }
        if (getWindow().superDispatchTouchEvent(ev)) {
            return true;
        }
        return onTouchEvent(ev);
    }

定义的时间参数在这里.
base/core/res/res/values/config.xml

   <!-- Activity scroll boost params -->
   <integer name="ascrollboost_timeout">17</integer>
   <integer name="ascrollboost_schedboost">0x1E01</integer>
   <integer name="ascrollboost_cpuboost">0x20F</integer>
   <integer name="ascrollboost_pcdisbl">0x101</integer>

获取相关的boots 时间参数后 就调用 下面的函数来进行加速.

    /* The following two functions are the PerfLock APIs*/
    /** &hide */
    public int perfLockAcquireTouch(MotionEvent ev, DisplayMetrics metrics,
                                                        int duration, int... list) {
        int rc = REQUEST_FAILED;
        final int actionMasked = ev.getActionMasked();
        final int pointerIndex = ev.getActionIndex();
        final int pointerId = ev.getPointerId(pointerIndex);
        final int y = (int) ev.getY(pointerIndex);
        final int x = (int) ev.getX(pointerIndex);

        int dx = (int)((x * 1f)/metrics.density);
        int dy = (int)((y * 1f)/metrics.density);

        boolean isBoostRequired = false;

        switch (actionMasked) {
            case MotionEvent.ACTION_DOWN: {
                if(mVelocityTracker == null) {
                    // Retrieve a new VelocityTracker object to watch the velocity of a motion.
                    mVelocityTracker = VelocityTracker.obtain();
                }
                else {
                    // Reset the velocity tracker back to its initial state.
                    mVelocityTracker.clear();
                }

                if(mVelocityTracker != null) {
                    // Add a user's movement to the tracker.
                    mVelocityTracker.addMovement(ev);
                }
                if (mTouchInfo == null) {
                    mTouchInfo = new TouchInfo();
                }
                if (mTouchInfo != null) {
                    // Reset drag boost params
                    mTouchInfo.reset();
                    // set start, current position
                    mTouchInfo.setStartXY(dx, dy);
                    // set drag movement thresholds
                    mTouchInfo.setDragWH((int)(mWDragPix * 1f/metrics.density),
                                         (int)(mHDragPix * 1f/metrics.density));
                }
                break;
            }

            case MotionEvent.ACTION_MOVE: {
                if(mVelocityTracker != null) {
                    // Add a user's movement to the tracker.
                    mVelocityTracker.addMovement(ev);
                }

                if(mTouchInfo != null) {
                    int xdiff = Math.abs(dx - mTouchInfo.mCurX);
                    int ydiff = Math.abs(dy - mTouchInfo.mCurY);
                    //set current position
                    mTouchInfo.setXY(dx, dy);

                    if ((xdiff > mTouchInfo.mMinDragW) ||
                        (ydiff > mTouchInfo.mMinDragH)) {
                        //drag detected. Boost it.
                        isBoostRequired = true;
                    }
                }
                break;
            }

            case MotionEvent.ACTION_UP: {
                if(mVelocityTracker != null) {
                    // Add a user's movement to the tracker
                    mVelocityTracker.addMovement(ev);
                    // compute velocity (pixel per second)
                    mVelocityTracker.computeCurrentVelocity(1000, mMaxVelocity);
                    final int initialVelocity =
                        Math.abs((int) mVelocityTracker.getYVelocity(pointerId));
                    if (initialVelocity > mMinVelocity) {
                        //Velocity is more than min velocity.Calculate fling boost duration.
                        duration *=  ((1f * initialVelocity)/(1f * mMinVelocity));
                        //Enable boost
                        isBoostRequired = true;
                        break;
                    }
                }
                if(mTouchInfo != null) {
                    int xdiff = Math.abs(dx - mTouchInfo.mCurX);
                    int ydiff = Math.abs(dy - mTouchInfo.mCurY);

                    if ((xdiff > mTouchInfo.mMinDragW) ||
                        (ydiff > mTouchInfo.mMinDragH)) {
                        //Only drag boost. Boost it.
                        isBoostRequired = true;
                    }
                }
                break;
            }

            case MotionEvent.ACTION_CANCEL: {
                if(mTouchInfo != null) {
                    mTouchInfo.reset();
                }
                break;
            }

            default:
                break;
        }
        **if(isBoostRequired ==  true) {
            handle = native_perf_lock_acq(handle, duration, list); // 执行boost 资源获取.
            if (handle != 0) {
               rc = REQUEST_SUCCEEDED;
            }
        }**
        return rc;
    }

3.JNI 层代码

frameworks/base/core/jni/org_codeaurora_Performance.cpp

static JNINativeMethod gMethods[] = {
    {"native_perf_lock_acq",  "(II[I)I",               (int *)org_codeaurora_performance_native_perf_lock_acq},
    {"native_perf_lock_rel",  "(I)I",                  (int *)org_codeaurora_performance_native_perf_lock_rel},
    {"native_deinit",         "()V",                   (void *)org_codeaurora_performance_native_deinit},
};


int register_org_codeaurora_Performance(JNIEnv *env)
{
    pthread_mutex_lock(&dl_mutex);
    org_codeaurora_performance_native_init();
    pthread_mutex_unlock(&dl_mutex);

    return AndroidRuntime::registerNativeMethods(env,
            "org/codeaurora/Performance", gMethods, NELEM(gMethods));// 注册提供的API函数. 只有3个方法. 比较简单.
}

device 目录下面有配置 property 库的路径.

PRODUCT_PROPERTY_OVERRIDES += \
    ro.vendor.extension_library=libqti-perfd-client.so \

最重要的一个init函数, 打开私有库 ,调取里面的方法. 
// ----------------------------------------------------------------------------

static void
org_codeaurora_performance_native_init()
{
    const char *rc;
    char buf[PROPERTY_VALUE_MAX];
    int len;

    /* Retrieve name of vendor extension library */
    if (property_get("ro.vendor.extension_library", buf, NULL) <= 0) {
        return;
    }

    /* Sanity check - ensure */
    buf[PROPERTY_VALUE_MAX-1] = '\0';
    if (strstr(buf, "/") != NULL) {
        return;
    }


    dlhandle = dlopen(buf, RTLD_NOW | RTLD_LOCAL);

    if (dlhandle == NULL) {
        return;
    }

    dlerror();


----------
获取最关键的2个方法. 

    **perf_lock_acq = (int (*) (int, int, int[], int))dlsym(dlhandle, "perf_lock_acq");
    if ((rc = dlerror()) != NULL) {
        goto cleanup;
    }
    perf_lock_rel = (int (*) (int))dlsym(dlhandle, "perf_lock_rel");
    if ((rc = dlerror()) != NULL) {
        goto cleanup;
    }**


----------


    return;

cleanup:
    perf_lock_acq  = NULL;
    perf_lock_rel  = NULL;
    if (dlhandle) {
        dlclose(dlhandle);
        dlhandle = NULL;
    }
}

1. 
   高通私有库的名称 : libqti-perfd-client
   vendor/qcom/proprietary/android-perf/mp-ctl

1.首先, 守护进程启动server—> mpctl_server_init()
2.client 发送服务请求到server.
mpctl_send(MPCTL_CMD_PERFLOCKREL, handle);
mpctl_send(MPCTL_CMD_PERFLOCKACQ, handle, duration, numArgs, list);
mpctl_send(MPCTL_CMD_PERFLOCKRESET);
3.server响应请求进行CPU底层操作.