1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
use {
    crate::{
        core::{device_owned, Device, DeviceId},
        family::QueueId,
    },
    rendy_core::hal::{device::Device as _, Backend},
};

/// Queue epoch is the point in particluar queue timeline when fence is submitted.

#[derive(Clone, Copy, Debug)]
pub struct FenceEpoch {
    /// Queue that signals fence.

    pub queue: QueueId,

    /// Queue epoch counter.

    pub epoch: u64,
}

#[derive(Clone, Copy, Debug)]
enum FenceState {
    Unsignaled,
    Signaled,
    Submitted(FenceEpoch),
}

/// Fence wrapper.

#[derive(Debug)]
pub struct Fence<B: Backend> {
    device: DeviceId,
    raw: B::Fence,
    state: FenceState,
}

device_owned!(Fence<B>);

impl<B> Fence<B>
where
    B: Backend,
{
    /// Create new fence in signaled or unsignaled state.

    pub fn new(
        device: &Device<B>,
        signaled: bool,
    ) -> Result<Self, rendy_core::hal::device::OutOfMemory> {
        let raw = device.raw().create_fence(false)?;
        Ok(Fence {
            device: device.id(),
            raw,
            state: if signaled {
                FenceState::Signaled
            } else {
                FenceState::Unsignaled
            },
        })
    }

    /// Check if fence was submitted.

    pub fn is_submitted(&self) -> bool {
        match self.state {
            FenceState::Submitted(_) => true,
            _ => false,
        }
    }

    /// Check if fence is signaled.

    pub fn is_signaled(&self) -> bool {
        match self.state {
            FenceState::Signaled => true,
            _ => false,
        }
    }

    /// Check if fence is unsignaled.

    /// It can be submitted as well.

    pub fn is_unsignaled(&self) -> bool {
        !self.is_signaled()
    }

    /// Panics if signaled or submitted.

    /// Becomes `Submitted` after.

    pub(crate) fn mark_submitted(&mut self, epoch: FenceEpoch) {
        match self.state {
            FenceState::Unsignaled => {
                self.state = FenceState::Submitted(epoch);
            }
            _ => panic!("Must be Unsignaled"),
        }
    }

    /// Reset signaled fence.

    /// Panics if not signaled.

    /// Becomes unsigneled.

    pub fn reset(
        &mut self,
        device: &Device<B>,
    ) -> Result<(), rendy_core::hal::device::OutOfMemory> {
        self.assert_device_owner(device);
        match self.state {
            FenceState::Signaled => {
                unsafe { device.reset_fence(&self.raw) }?;
                self.state = FenceState::Unsignaled;
                Ok(())
            }
            _ => panic!("Must be signaled"),
        }
    }

    /// Mark signaled fence as reset.

    /// Panics if not signaled.

    /// Becomes unsigneled.

    /// Fence must be reset using raw fence value.

    pub unsafe fn mark_reset(&mut self) {
        match self.state {
            FenceState::Signaled => {
                self.state = FenceState::Unsignaled;
            }
            _ => panic!("Must be signaled"),
        }
    }

    /// Mark fence as signaled.

    /// Panics if not submitted.

    /// Fence must be checked to be signaled using raw fence value.

    pub unsafe fn mark_signaled(&mut self) -> FenceEpoch {
        match self.state {
            FenceState::Submitted(epoch) => {
                self.state = FenceState::Signaled;
                epoch
            }
            _ => panic!("Must be submitted"),
        }
    }

    /// Wait for fence to become signaled.

    /// Panics if not submitted.

    /// Returns submission epoch on success.

    pub fn wait_signaled(
        &mut self,
        device: &Device<B>,
        timeout_ns: u64,
    ) -> Result<Option<FenceEpoch>, rendy_core::hal::device::OomOrDeviceLost> {
        self.assert_device_owner(device);

        match self.state {
            FenceState::Submitted(epoch) => {
                if unsafe { device.wait_for_fence(&self.raw, timeout_ns) }? {
                    self.state = FenceState::Signaled;
                    Ok(Some(epoch))
                } else {
                    Ok(None)
                }
            }
            _ => panic!("Must be submitted"),
        }
    }

    /// Check if fence has became signaled.

    /// Panics if not submitted.

    /// Returns submission epoch on success.

    pub fn check_signaled(
        &mut self,
        device: &Device<B>,
    ) -> Result<Option<FenceEpoch>, rendy_core::hal::device::DeviceLost> {
        self.assert_device_owner(device);

        match self.state {
            FenceState::Submitted(epoch) => {
                if unsafe { device.get_fence_status(&self.raw) }? {
                    self.state = FenceState::Signaled;
                    Ok(Some(epoch))
                } else {
                    Ok(None)
                }
            }
            _ => panic!("Must be submitted"),
        }
    }

    /// Get raw fence reference.

    /// Use `mark_*` functions to reflect stage changes.

    pub fn raw(&self) -> &B::Fence {
        &self.raw
    }

    /// Get submission epoch.

    /// Panics if not submitted.

    pub fn epoch(&self) -> FenceEpoch {
        match self.state {
            FenceState::Submitted(epoch) => epoch,
            _ => panic!("Must be submitted"),
        }
    }

    /// Unwrap raw fence value.

    /// Panics if submitted.

    pub fn into_inner(self) -> B::Fence {
        match self.state {
            FenceState::Signaled | FenceState::Unsignaled => self.raw,
            _ => panic!("Submitted fence must be waited upon before destroying"),
        }
    }
}