1
=== modified file 'src/client/frame_clock.cpp'
2
--- src/client/frame_clock.cpp	2016-11-29 08:00:45 +0000
3
+++ src/client/frame_clock.cpp	2017-02-27 08:17:57 +0000
4
@@ -103,7 +103,7 @@
5
103
     * Crucially this is not required on most frames, so that even if it is
103
     * Crucially this is not required on most frames, so that even if it is
6
104
     * implemented as a round trip to the server, that won't happen often.
104
     * implemented as a round trip to the server, that won't happen often.
7
105
     */
105
     */
9
106
    if (missed_frames > 1 || config_changed)
106
    if (missed_frames > 1 || config_changed || demerits > 0)
10
107
    {
107
    {
11
108
        lock.unlock();
108
        lock.unlock();
12
109
        auto const server_frame = resync_callback();
109
        auto const server_frame = resync_callback();
13
@@ -151,6 +151,12 @@
14
151
        // FIXME? Missing += operator
151
        // FIXME? Missing += operator
15
152
        target = target + missed_frames * period;
152
        target = target + missed_frames * period;
16
153
    }
153
    }
17
154
    else
18
155
    {
19
156
        demerits = 0;
20
157
    }
21
158
22
159
    demerits += missed_frames;
23
154
160
24
155
    return target;
161
    return target;
25
156
}
162
}
26
157
163
27
=== modified file 'src/client/frame_clock.h'
28
--- src/client/frame_clock.h	2016-12-15 08:15:54 +0000
29
+++ src/client/frame_clock.h	2017-02-27 08:17:57 +0000
30
@@ -66,6 +66,7 @@
31
66
    mutable bool config_changed;
66
    mutable bool config_changed;
32
67
    std::chrono::nanoseconds period;
67
    std::chrono::nanoseconds period;
33
68
    ResyncCallback resync_callback;
68
    ResyncCallback resync_callback;
34
69
    mutable long demerits = 0;
35
69
};
70
};
36
70
71
37
71
}} // namespace mir::client
72
}} // namespace mir::client
38
72
73
39
=== modified file 'tests/unit-tests/client/test_frame_clock.cpp'
40
--- tests/unit-tests/client/test_frame_clock.cpp	2016-11-29 08:17:27 +0000
41
+++ tests/unit-tests/client/test_frame_clock.cpp	2017-02-27 08:17:57 +0000
42
@@ -395,6 +395,94 @@
43
395
    EXPECT_EQ(one_frame, e - d);        // No frame skipped. We have recovered.
395
    EXPECT_EQ(one_frame, e - d);        // No frame skipped. We have recovered.
44
396
}
396
}
45
397
397
46
398
TEST_F(FrameClockTest, repeatedly_missing_frame_deadline_targets_the_future)
47
399
{   // Regression test for LP: #1665802
48
400
    FrameClock clock(with_fake_time);
49
401
    clock.set_period(one_frame);
50
402
51
403
    PosixTimestamp a;
52
404
    auto b = clock.next_frame_after(a);
53
405
54
406
    fake_sleep_until(b);
55
407
    fake_sleep_for(one_frame * 3 / 2);  // Render time: 1.5 frames
56
408
57
409
    auto c = clock.next_frame_after(b);
58
410
    ASSERT_EQ(one_frame, c - b);        // No frame skipped
59
411
60
412
    fake_sleep_until(c);
61
413
    fake_sleep_for(one_frame * 8 / 5);  // Render time: 1.6 frames
62
414
63
415
    auto d = clock.next_frame_after(c);
64
416
    ASSERT_EQ(2*one_frame, d - c);      // One frame skipped
65
417
66
418
    /*
67
419
     * Ensure that a client repeatedly missing the frame deadline does not
68
420
     * repeatedly try to catch up, which may saturate the GPU (as found
69
421
     * on Adreno) when using a sub-par driver (like Freedreno/Gallium drivers),
70
422
     * starving the server of GPU time. (LP: #1665802)
71
423
     */
72
424
    for (int slow_frame = 0; slow_frame < 100; ++slow_frame)
73
425
    {
74
426
        fake_sleep_for(one_frame * 8 / 5);  // Render time: 1.6 frames
75
427
        c = d;
76
428
        d = clock.next_frame_after(d);
77
429
        auto& now = fake_time[d.clock_id];
78
430
        ASSERT_GT(d, now) << "slow frame #" << slow_frame;
79
431
        ASSERT_EQ(2*one_frame, d - c) << "slow frame #" << slow_frame;
80
432
        fake_sleep_until(d);
81
433
    }
82
434
83
435
    auto e = d;
84
436
85
437
    /*
86
438
     * If the client speeds up, we should quickly allow it to regain full
87
439
     * frame rate:
88
440
     */
89
441
    for (int fast_frame = 0; fast_frame < 100; ++fast_frame)
90
442
    {
91
443
        fake_sleep_for(one_frame/4);  // Short render time, immediate recovery
92
444
        e = clock.next_frame_after(d);
93
445
        ASSERT_EQ(one_frame, e - d) << "fast frame #" << fast_frame;
94
446
        fake_sleep_until(e);
95
447
        d = e;
96
448
    }
97
449
98
450
    auto f = e;
99
451
100
452
    /*
101
453
     * In the original bug report the Adreno could only sustain 15 FPS without
102
454
     * saturating the GPU. When it was trying to catch up and maintain
103
455
     * 20-30 FPS, that was enough to saturate the GPU and the server couldn't
104
456
     * display anything...
105
457
     */
106
458
    for (int really_slow_frame = 0; really_slow_frame < 100; ++really_slow_frame)
107
459
    {
108
460
        fake_sleep_for(one_frame * 17 / 5);  // Render time: 3.4 frames
109
461
        f = clock.next_frame_after(e);
110
462
        auto& now = fake_time[f.clock_id];
111
463
        ASSERT_GT(f, now) << "really slow frame #" << really_slow_frame;
112
464
        ASSERT_EQ(4*one_frame, f - e) << "really slow frame #" << really_slow_frame;
113
465
        fake_sleep_until(f);
114
466
        e = f;
115
467
    }
116
468
117
469
    auto g = f;
118
470
119
471
    /*
120
472
     * If the client speeds up, we should quickly allow it to regain full
121
473
     * frame rate:
122
474
     */
123
475
    for (int fast_frame = 0; fast_frame < 100; ++fast_frame)
124
476
    {
125
477
        fake_sleep_for(one_frame/4);  // Short render time, immediate recovery
126
478
        g = clock.next_frame_after(f);
127
479
        ASSERT_EQ(one_frame, g - f) << "fast frame #" << fast_frame;
128
480
        fake_sleep_until(g);
129
481
        f = g;
130
482
    }
131
483
132
484
}
133
485
134
398
TEST_F(FrameClockTest, nesting_adds_zero_lag)
486
TEST_F(FrameClockTest, nesting_adds_zero_lag)
135
399
{
487
{
136
400
    FrameClock inner(with_fake_time);
488
    FrameClock inner(with_fake_time);
Reviewer	Review Type	Status
Mir CI Bot	continuous-integration	Needs Fixing on 2017-02-24
Daniel van Vugt		Disapprove on 2017-02-23
Review via email: mp+318084@code.launchpad.net