Jack2: JackEngineControl.cpp Source File

Jack2 1.9.12

JackEngineControl.cpp
1 /*
2 Copyright (C) 2003 Paul Davis
3 Copyright (C) 2004-2008 Grame
4
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU Lesser General Public License as published by
7 the Free Software Foundation; either version 2.1 of the License, or
8 (at your option) any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18
19 */
20
21 #include "JackClientInterface.h"
22 #include "JackEngineControl.h"
23 #include "JackGraphManager.h"
24 #include "JackClientControl.h"
25 #include <algorithm>
26 #include <math.h>
27
28 namespace Jack
29 {
30
31 static inline jack_time_t JACK_MAX(jack_time_t a, jack_time_t b)
32 {
33 return (a < b) ? b : a;
34 }
35
36 void JackEngineControl::CalcCPULoad(JackClientInterface** table,
37 JackGraphManager* manager,
38 jack_time_t cur_cycle_begin,
39 jack_time_t prev_cycle_end)
40 {
41 fPrevCycleTime = fCurCycleTime;
42 fCurCycleTime = cur_cycle_begin;
43 jack_time_t last_cycle_end = prev_cycle_end;
44
45 // In Asynchronous mode, last cycle end is the max of client end dates
46 if (!fSyncMode) {
47 for (int i = fDriverNum; i < CLIENT_NUM; i++) {
48 JackClientInterface* client = table[i];
49 JackClientTiming* timing = manager->GetClientTiming(i);
50 if (client && client->GetClientControl()->fActive && timing->fStatus == Finished) {
51 last_cycle_end = JACK_MAX(last_cycle_end, timing->fFinishedAt);
52 }
53 }
54 }
55
56 // Store the execution time for later averaging
57 if (last_cycle_end > 0) {
58 fRollingClientUsecs[fRollingClientUsecsIndex++] = last_cycle_end - fPrevCycleTime;
59 }
60 if (fRollingClientUsecsIndex >= JACK_ENGINE_ROLLING_COUNT) {
61 fRollingClientUsecsIndex = 0;
62 }
63
64 // Each time we have a full set of iterations, recompute the current
65 // usage from the latest JACK_ENGINE_ROLLING_COUNT client entries.
66 if (fRollingClientUsecsCnt && (fRollingClientUsecsIndex == 0)) {
67 jack_time_t avg_usecs = 0;
68 jack_time_t max_usecs = 0;
69
70 for (int i = 0; i < JACK_ENGINE_ROLLING_COUNT; i++) {
71 avg_usecs += fRollingClientUsecs[i]; // This is really a running total to be averaged later
72 max_usecs = JACK_MAX(fRollingClientUsecs[i], max_usecs);
73 }
74
75 fMaxUsecs = JACK_MAX(fMaxUsecs, max_usecs);
76
77 if (max_usecs < ((fPeriodUsecs * 95) / 100)) {
78 // Average the values from our JACK_ENGINE_ROLLING_COUNT array
79 fSpareUsecs = (jack_time_t)(fPeriodUsecs - (avg_usecs / JACK_ENGINE_ROLLING_COUNT));
80 } else {
81 // Use the 'worst case' value (or zero if we exceeded 'fPeriodUsecs')
82 fSpareUsecs = jack_time_t((max_usecs < fPeriodUsecs) ? fPeriodUsecs - max_usecs : 0);
83 }
84
85 fCPULoad = ((1.f - (float(fSpareUsecs) / float(fPeriodUsecs))) * 50.f + (fCPULoad * 0.5f));
86 }
87
88 fRollingClientUsecsCnt++;
89 }
90
91 void JackEngineControl::ResetRollingUsecs()
92 {
93 memset(fRollingClientUsecs, 0, sizeof(fRollingClientUsecs));
94 fRollingClientUsecsIndex = 0;
95 fRollingClientUsecsCnt = 0;
96 fSpareUsecs = 0;
97 fRollingInterval = int(floor((JACK_ENGINE_ROLLING_INTERVAL * 1000.f) / fPeriodUsecs));
98 }
99
100 void JackEngineControl::NotifyXRun(jack_time_t callback_usecs, float delayed_usecs)
101 {
102 ResetFrameTime(callback_usecs);
103 fXrunDelayedUsecs = delayed_usecs;
104 if (delayed_usecs > fMaxDelayedUsecs) {
105 fMaxDelayedUsecs = delayed_usecs;
106 }
107 }
108
109 } // end of namespace