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

use super::DescriptorSetWriteSet;
use super::ManagedDescriptorSetPool;
use super::{DescriptorSetArc, FrameInFlightIndex};
use crate::resources::resource_lookup::{DescriptorSetLayoutResource, ResourceHash};
use crate::resources::{DynDescriptorSet, ResourceArc};
use fnv::FnvHashMap;
use rafx_api::{RafxDeviceContext, RafxResult};

#[derive(Debug)]
pub struct DescriptorSetPoolMetrics {
    pub hash: ResourceHash,
    pub allocated_count: usize,
}

#[derive(Debug)]
pub struct DescriptorSetAllocatorMetrics {
    pub pools: Vec<DescriptorSetPoolMetrics>,
}

pub struct DescriptorSetAllocator {
    device_context: RafxDeviceContext,
    pools: FnvHashMap<ResourceHash, ManagedDescriptorSetPool>,

    // This index represents the set of resources that will be written to when update() is called.
    frame_in_flight_index: FrameInFlightIndex,
}

impl DescriptorSetAllocator {
    pub fn new(device_context: &RafxDeviceContext) -> Self {
        DescriptorSetAllocator {
            device_context: device_context.clone(),
            pools: Default::default(),
            frame_in_flight_index: 0,
        }
    }

    pub fn metrics(&self) -> DescriptorSetAllocatorMetrics {
        let mut registered_descriptor_sets_stats = Vec::with_capacity(self.pools.len());
        for (hash, value) in &self.pools {
            let pool_stats = DescriptorSetPoolMetrics {
                hash: *hash,
                allocated_count: value.slab.allocated_count(),
            };
            registered_descriptor_sets_stats.push(pool_stats);
        }

        DescriptorSetAllocatorMetrics {
            pools: registered_descriptor_sets_stats,
        }
    }

    #[profiling::function]
    pub fn flush_changes(&mut self) -> RafxResult<()> {
        // Now process drops and flush writes to GPU
        for pool in self.pools.values_mut() {
            pool.flush_changes(self.frame_in_flight_index)?;
        }

        Ok(())
    }

    #[profiling::function]
    pub fn on_frame_complete(&mut self) {
        // Bump frame in flight index
        self.frame_in_flight_index =
            super::add_to_frame_in_flight_index(self.frame_in_flight_index, 1);
    }

    pub fn destroy(&mut self) -> RafxResult<()> {
        for pool in self.pools.values_mut() {
            pool.destroy(&self.device_context)?;
        }

        self.pools.clear();
        Ok(())
    }

    //TODO: Is creating and immediately modifying causing multiple writes?
    fn do_create_dyn_descriptor_set(
        &mut self,
        descriptor_set_layout: &ResourceArc<DescriptorSetLayoutResource>,
        write_set: DescriptorSetWriteSet,
    ) -> RafxResult<DynDescriptorSet> {
        let descriptor_set =
            self.create_descriptor_set_with_writes(descriptor_set_layout, write_set.clone())?;

        // Create the DynDescriptorSet
        let dyn_descriptor_set =
            DynDescriptorSet::new(descriptor_set_layout, descriptor_set, write_set);

        Ok(dyn_descriptor_set)
    }

    pub fn create_descriptor_set_with_writes(
        &mut self,
        descriptor_set_layout: &ResourceArc<DescriptorSetLayoutResource>,
        write_set: DescriptorSetWriteSet,
    ) -> RafxResult<DescriptorSetArc> {
        // Get or create the pool for the layout
        let hash = descriptor_set_layout.get_hash().into();
        let device_context = self.device_context.clone();
        let pool = self.pools.entry(hash).or_insert_with(|| {
            ManagedDescriptorSetPool::new(&device_context, descriptor_set_layout.clone())
        });

        // Allocate a descriptor set
        pool.insert(&self.device_context, write_set)
    }

    pub fn create_descriptor_set<'a, T: DescriptorSetInitializer<'a>>(
        &mut self,
        descriptor_set_layout: &ResourceArc<DescriptorSetLayoutResource>,
        args: T,
    ) -> RafxResult<DescriptorSetArc> {
        let descriptor_set = self.create_dyn_descriptor_set_uninitialized(descriptor_set_layout)?;
        T::create_descriptor_set(self, descriptor_set, args)
    }

    pub fn create_dyn_descriptor_set_uninitialized(
        &mut self,
        descriptor_set_layout: &ResourceArc<DescriptorSetLayoutResource>,
    ) -> RafxResult<DynDescriptorSet> {
        let write_set = super::create_uninitialized_write_set_for_layout(
            &descriptor_set_layout.get_raw().descriptor_set_layout_def,
        );
        self.do_create_dyn_descriptor_set(descriptor_set_layout, write_set)
    }

    pub fn create_dyn_descriptor_set<'a, T: DescriptorSetInitializer<'a>>(
        &mut self,
        descriptor_set_layout: &ResourceArc<DescriptorSetLayoutResource>,
        args: T,
    ) -> RafxResult<<T as DescriptorSetInitializer<'a>>::Output> {
        Ok(T::create_dyn_descriptor_set(
            self.create_dyn_descriptor_set_uninitialized(descriptor_set_layout)?,
            args,
        ))
    }
}

// The lifetime here is required so that implementations of it can bind to it
pub trait DescriptorSetInitializer<'a> {
    type Output;

    fn create_dyn_descriptor_set(
        descriptor_set: DynDescriptorSet,
        args: Self,
    ) -> Self::Output;
    fn create_descriptor_set(
        descriptor_set_allocator: &mut DescriptorSetAllocator,
        descriptor_set: DynDescriptorSet,
        args: Self,
    ) -> RafxResult<DescriptorSetArc>;
}