haiku/src/system/libroot/os/scheduler.c

/* 
 * Copyright 2004-2007, Haiku. All rights reserved.
 * Distributed under the terms of the MIT License.
 *
 * Authors:
 *      Jérôme Duval, korli@users.sourceforge.net.
 *      Michael Pfeiffer, laplace@users.sourceforge.net
 */


#include <scheduler.h>


static struct {
	uint32 what;
	int32 priority;
} gWhatPriorityArray[] = {
	// highest priority first
	{B_MIDI_PROCESSING, 0x78},
	{B_AUDIO_RECORDING | B_AUDIO_PLAYBACK, 0x73},
	{B_LIVE_AUDIO_MANIPULATION, 0x6e},
	{B_VIDEO_RECORDING, 0x19},
	{B_VIDEO_PLAYBACK, 0x14},
	{B_USER_INPUT_HANDLING, 0x0f},
	{B_LIVE_VIDEO_MANIPULATION, 0x0e},
	{B_LIVE_3D_RENDERING, 0x0c},
	{B_STATUS_RENDERING, 0xa},
	{B_OFFLINE_PROCESSING, 0x06},
	{B_NUMBER_CRUNCHING, 0x05},
	{(uint32)-1, -1}
};

int32 
suggest_thread_priority(uint32 what, int32 period, bigtime_t jitter, bigtime_t length)
{
	int i;
	int32 priority = what == B_DEFAULT_MEDIA_PRIORITY ? 0x0a : 0;
		// default priority
	
	for (i = 0; gWhatPriorityArray[i].what != (uint32)-1; i ++) {
		if ((what & gWhatPriorityArray[i].what) != 0) {
			priority = gWhatPriorityArray[i].priority;
			break;
		}
	}
	
	return priority;	
}

bigtime_t 
estimate_max_scheduling_latency(thread_id th)
{
	if (th == -1)
		th = find_thread(NULL);

	return 0;
}