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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
use std::mem;
use std::rc::Rc;
use crate::device::GpuFrameId;
use crate::profiler::GpuProfileTag;
/// Backend-defined identifier of a GPU query object.
#[derive(Copy, Clone, Debug, PartialEq)]
pub struct GpuQueryId(pub(super) u32);
#[derive(Copy, Clone, Debug, PartialEq)]
pub enum GpuQueryKind {
/// GPU time in nanoseconds spent on the commands between begin and end.
TimeElapsed,
/// Number of samples that passed the depth test between begin and end.
SamplesPassed,
}
/// GPU queries and command stream annotations, as provided by a backend
/// for the GPU profiler. At most one query of each kind is active at a time.
pub trait GpuQueryBackend {
fn create_queries(&self, count: usize) -> Vec<GpuQueryId>;
fn delete_queries(&self, queries: &[GpuQueryId]);
fn begin_query(&self, kind: GpuQueryKind, query: GpuQueryId);
fn end_query(&self, kind: GpuQueryKind);
/// Returns the result of a finished query, waiting for it if needed.
fn query_result(&self, query: GpuQueryId) -> u64;
/// Whether the marker methods below annotate the command stream.
fn supports_markers(&self) -> bool;
fn push_marker_group(&self, label: &str);
fn pop_marker_group(&self);
fn insert_marker(&self, label: &str);
}
#[derive(Debug, Clone)]
pub struct GpuTimer {
pub tag: GpuProfileTag,
pub time_ns: u64,
}
#[derive(Debug, Clone)]
pub struct GpuSampler {
pub tag: GpuProfileTag,
pub count: u64,
}
pub struct QuerySet<T> {
set: Vec<GpuQueryId>,
data: Vec<T>,
pending: Option<GpuQueryId>,
}
impl<T> QuerySet<T> {
fn new() -> Self {
QuerySet {
set: Vec::new(),
data: Vec::new(),
pending: None,
}
}
fn reset(&mut self) {
self.data.clear();
self.pending = None;
}
fn add(&mut self, value: T) -> Option<GpuQueryId> {
assert_eq!(self.pending, None);
self.set.get(self.data.len()).cloned().map(|query_id| {
self.data.push(value);
self.pending = Some(query_id);
query_id
})
}
fn take<F: Fn(&mut T, GpuQueryId)>(&mut self, fun: F) -> Vec<T> {
let mut data = mem::replace(&mut self.data, Vec::new());
for (value, &query) in data.iter_mut().zip(self.set.iter()) {
fun(value, query)
}
data
}
}
pub struct GpuFrameProfile {
queries: Rc<dyn GpuQueryBackend>,
timers: QuerySet<GpuTimer>,
samplers: QuerySet<GpuSampler>,
frame_id: GpuFrameId,
inside_frame: bool,
}
impl GpuFrameProfile {
fn new(queries: Rc<dyn GpuQueryBackend>) -> Self {
GpuFrameProfile {
queries,
timers: QuerySet::new(),
samplers: QuerySet::new(),
frame_id: GpuFrameId::new(0),
inside_frame: false,
}
}
fn enable_timers(&mut self, count: usize) {
self.timers.set = self.queries.create_queries(count);
}
fn disable_timers(&mut self) {
if !self.timers.set.is_empty() {
self.queries.delete_queries(&self.timers.set);
}
self.timers.set = Vec::new();
}
fn enable_samplers(&mut self, count: usize) {
self.samplers.set = self.queries.create_queries(count);
}
fn disable_samplers(&mut self) {
if !self.samplers.set.is_empty() {
self.queries.delete_queries(&self.samplers.set);
}
self.samplers.set = Vec::new();
}
fn begin_frame(&mut self, frame_id: GpuFrameId) {
self.frame_id = frame_id;
self.timers.reset();
self.samplers.reset();
self.inside_frame = true;
}
fn end_frame(&mut self) {
self.finish_timer();
self.finish_sampler();
self.inside_frame = false;
}
fn finish_timer(&mut self) {
debug_assert!(self.inside_frame);
if self.timers.pending.is_some() {
self.queries.end_query(GpuQueryKind::TimeElapsed);
self.timers.pending = None;
}
}
fn finish_sampler(&mut self) {
debug_assert!(self.inside_frame);
if self.samplers.pending.is_some() {
self.queries.end_query(GpuQueryKind::SamplesPassed);
self.samplers.pending = None;
}
}
fn start_timer(&mut self, tag: GpuProfileTag) -> GpuTimeQuery {
self.finish_timer();
let marker = GpuMarker::new(&self.queries, tag.label);
if let Some(query) = self.timers.add(GpuTimer { tag, time_ns: 0 }) {
self.queries.begin_query(GpuQueryKind::TimeElapsed, query);
}
GpuTimeQuery(marker)
}
fn start_sampler(&mut self, tag: GpuProfileTag) -> GpuSampleQuery {
self.finish_sampler();
if let Some(query) = self.samplers.add(GpuSampler { tag, count: 0 }) {
self.queries.begin_query(GpuQueryKind::SamplesPassed, query);
}
GpuSampleQuery
}
fn build_samples(&mut self) -> (GpuFrameId, Vec<GpuTimer>, Vec<GpuSampler>) {
debug_assert!(!self.inside_frame);
let queries = &self.queries;
(
self.frame_id,
self.timers.take(|timer, query| {
timer.time_ns = queries.query_result(query)
}),
self.samplers.take(|sampler, query| {
sampler.count = queries.query_result(query)
}),
)
}
}
impl Drop for GpuFrameProfile {
fn drop(&mut self) {
self.disable_timers();
self.disable_samplers();
}
}
const NUM_PROFILE_FRAMES: usize = 4;
pub struct GpuProfiler {
queries: Rc<dyn GpuQueryBackend>,
frames: [GpuFrameProfile; NUM_PROFILE_FRAMES],
next_frame: usize,
}
impl GpuProfiler {
pub fn new(queries: Rc<dyn GpuQueryBackend>) -> Self {
let f = || GpuFrameProfile::new(Rc::clone(&queries));
let frames = [f(), f(), f(), f()];
GpuProfiler {
queries,
next_frame: 0,
frames,
}
}
pub fn enable_timers(&mut self) {
const MAX_TIMERS_PER_FRAME: usize = 256;
for frame in &mut self.frames {
frame.enable_timers(MAX_TIMERS_PER_FRAME);
}
}
pub fn disable_timers(&mut self) {
for frame in &mut self.frames {
frame.disable_timers();
}
}
pub fn enable_samplers(&mut self) {
const MAX_SAMPLERS_PER_FRAME: usize = 16;
if cfg!(target_os = "macos") {
warn!("Expect macOS driver bugs related to sample queries")
}
for frame in &mut self.frames {
frame.enable_samplers(MAX_SAMPLERS_PER_FRAME);
}
}
pub fn disable_samplers(&mut self) {
for frame in &mut self.frames {
frame.disable_samplers();
}
}
pub fn build_samples(&mut self) -> (GpuFrameId, Vec<GpuTimer>, Vec<GpuSampler>) {
self.frames[self.next_frame].build_samples()
}
pub fn begin_frame(&mut self, frame_id: GpuFrameId) {
self.frames[self.next_frame].begin_frame(frame_id);
}
pub fn end_frame(&mut self) {
self.frames[self.next_frame].end_frame();
self.next_frame = (self.next_frame + 1) % self.frames.len();
}
pub fn start_timer(&mut self, tag: GpuProfileTag) -> GpuTimeQuery {
self.frames[self.next_frame].start_timer(tag)
}
pub fn start_sampler(&mut self, tag: GpuProfileTag) -> GpuSampleQuery {
self.frames[self.next_frame].start_sampler(tag)
}
pub fn finish_sampler(&mut self, _sampler: GpuSampleQuery) {
self.frames[self.next_frame].finish_sampler()
}
pub fn start_marker(&mut self, label: &str) -> GpuMarker {
GpuMarker::new(&self.queries, label)
}
pub fn place_marker(&mut self, label: &str) {
GpuMarker::fire(&self.queries, label)
}
}
/// A marker group in the command stream, closed when dropped.
#[must_use]
pub struct GpuMarker {
queries: Option<Rc<dyn GpuQueryBackend>>,
}
impl GpuMarker {
fn new(queries: &Rc<dyn GpuQueryBackend>, message: &str) -> Self {
let queries = if queries.supports_markers() {
queries.push_marker_group(message);
Some(Rc::clone(queries))
} else {
None
};
GpuMarker { queries }
}
fn fire(queries: &Rc<dyn GpuQueryBackend>, message: &str) {
if queries.supports_markers() {
queries.insert_marker(message);
}
}
}
impl Drop for GpuMarker {
fn drop(&mut self) {
if let Some(ref queries) = self.queries {
queries.pop_marker_group();
}
}
}
#[must_use]
pub struct GpuTimeQuery(#[allow(dead_code)] GpuMarker);
#[must_use]
pub struct GpuSampleQuery;