Merge "Adjust wifi idle times to fit in system time period" into nyc-dev

        delta.mTimestamp = latest.getTimeStamp();

        delta.mStackState = latest.getStackState();

        // These times seem to be the most reliable.

        delta.mControllerTxTimeMs = latest.mControllerTxTimeMs - lastTxMs;

        delta.mControllerRxTimeMs = latest.mControllerRxTimeMs - lastRxMs;

        final long txTimeMs = latest.mControllerTxTimeMs - lastTxMs;

        final long rxTimeMs = latest.mControllerRxTimeMs - lastRxMs;

        final long idleTimeMs = latest.mControllerIdleTimeMs - lastIdleMs;

        // WiFi calculates the idle time as a difference from the on time and the various

        // Rx + Tx times. There seems to be some missing time there because this sometimes

        // becomes negative. Just cap it at 0 and move on.

        // b/21613534

        delta.mControllerIdleTimeMs = Math.max(0, latest.mControllerIdleTimeMs - lastIdleMs);

        delta.mControllerEnergyUsed = Math.max(0, latest.mControllerEnergyUsed - lastEnergy);

        if (delta.mControllerTxTimeMs < 0 || delta.mControllerRxTimeMs < 0) {

        if (txTimeMs < 0 || rxTimeMs < 0) {

            // The stats were reset by the WiFi system (which is why our delta is negative).

            // Returns the unaltered stats.

            delta.mControllerEnergyUsed = latest.mControllerEnergyUsed;

            delta.mControllerRxTimeMs = latest.mControllerRxTimeMs;

            delta.mControllerTxTimeMs = latest.mControllerTxTimeMs;

            delta.mControllerIdleTimeMs = latest.mControllerIdleTimeMs;

            Slog.v(TAG, "WiFi energy data was reset, new WiFi energy data is " + delta);

        }

        // There is some accuracy error in reports so allow some slop in the results.

        final long SAMPLE_ERROR_MILLIS = 750;

        final long totalTimeMs = delta.mControllerIdleTimeMs + delta.mControllerRxTimeMs +

                delta.mControllerTxTimeMs;

        if (totalTimeMs > timePeriodMs + SAMPLE_ERROR_MILLIS) {

        } else {

            final long totalActiveTimeMs = txTimeMs + rxTimeMs;

            long maxExpectedIdleTimeMs;

            // Active time can never be greater than the total time, the stats received seem

            // to be corrupt.

            if (totalActiveTimeMs > timePeriodMs) {

                maxExpectedIdleTimeMs = timePeriodMs;

                StringBuilder sb = new StringBuilder();

            sb.append("Total time ");

            TimeUtils.formatDuration(totalTimeMs, sb);

                sb.append("Total Active time ");

                TimeUtils.formatDuration(totalActiveTimeMs, sb);

                sb.append(" is longer than sample period ");

                TimeUtils.formatDuration(timePeriodMs, sb);

                sb.append(".\n");

                TimeUtils.formatDuration(latest.mControllerTxTimeMs, sb);

                sb.append(" e=").append(latest.mControllerEnergyUsed);

                Slog.wtf(TAG, sb.toString());

            } else {

                maxExpectedIdleTimeMs = timePeriodMs - totalActiveTimeMs;

            }

            // These times seem to be the most reliable.

            delta.mControllerTxTimeMs = txTimeMs;

            delta.mControllerRxTimeMs = rxTimeMs;

            // WiFi calculates the idle time as a difference from the on time and the various

            // Rx + Tx times. There seems to be some missing time there because this sometimes

            // becomes negative. Just cap it at 0 and ensure that it is less than the expected idle

            // time from the difference in timestamps.

            // b/21613534

            delta.mControllerIdleTimeMs = Math.min(maxExpectedIdleTimeMs, Math.max(0, idleTimeMs));

            delta.mControllerEnergyUsed = Math.max(0, latest.mControllerEnergyUsed - lastEnergy);

        }

        mLastInfo = latest;