Self-Profiling: Refactor SelfProfiler API to be RAII based where possible.

This commit is contained in:
Michael Woerister 2019-09-27 14:03:09 +02:00
parent bf8491e72e
commit b0b073cdb0
3 changed files with 249 additions and 115 deletions

View File

@ -32,7 +32,7 @@ use syntax::source_map;
use syntax::parse::{self, ParseSess};
use syntax::symbol::Symbol;
use syntax_pos::{MultiSpan, Span};
use crate::util::profiling::SelfProfiler;
use crate::util::profiling::{SelfProfiler, SelfProfilerRef};
use rustc_target::spec::{PanicStrategy, RelroLevel, Target, TargetTriple};
use rustc_data_structures::flock;
@ -129,7 +129,7 @@ pub struct Session {
pub profile_channel: Lock<Option<mpsc::Sender<ProfileQueriesMsg>>>,
/// Used by `-Z self-profile`.
pub self_profiling: Option<Arc<SelfProfiler>>,
pub prof: SelfProfilerRef,
/// Some measurements that are being gathered during compilation.
pub perf_stats: PerfStats,
@ -835,24 +835,6 @@ impl Session {
}
}
#[inline(never)]
#[cold]
fn profiler_active<F: FnOnce(&SelfProfiler) -> ()>(&self, f: F) {
match &self.self_profiling {
None => bug!("profiler_active() called but there was no profiler active"),
Some(profiler) => {
f(&profiler);
}
}
}
#[inline(always)]
pub fn profiler<F: FnOnce(&SelfProfiler) -> ()>(&self, f: F) {
if unlikely!(self.self_profiling.is_some()) {
self.profiler_active(f)
}
}
pub fn print_perf_stats(&self) {
println!(
"Total time spent computing symbol hashes: {}",
@ -1257,7 +1239,7 @@ fn build_session_(
imported_macro_spans: OneThread::new(RefCell::new(FxHashMap::default())),
incr_comp_session: OneThread::new(RefCell::new(IncrCompSession::NotInitialized)),
cgu_reuse_tracker,
self_profiling: self_profiler,
prof: SelfProfilerRef::new(self_profiler),
profile_channel: Lock::new(None),
perf_stats: PerfStats {
symbol_hash_time: Lock::new(Duration::from_secs(0)),

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@ -45,6 +45,7 @@ use crate::ty::CanonicalPolyFnSig;
use crate::util::common::ErrorReported;
use crate::util::nodemap::{DefIdMap, DefIdSet, ItemLocalMap, ItemLocalSet};
use crate::util::nodemap::{FxHashMap, FxHashSet};
use crate::util::profiling::SelfProfilerRef;
use errors::DiagnosticBuilder;
use arena::SyncDroplessArena;
@ -995,6 +996,8 @@ pub struct GlobalCtxt<'tcx> {
pub dep_graph: DepGraph,
pub prof: SelfProfilerRef,
/// Common objects.
pub common: Common<'tcx>,
@ -1225,6 +1228,7 @@ impl<'tcx> TyCtxt<'tcx> {
arena: WorkerLocal::new(|_| Arena::default()),
interners,
dep_graph,
prof: s.prof.clone(),
common,
types: common_types,
lifetimes: common_lifetimes,

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@ -1,9 +1,9 @@
use std::borrow::Cow;
use std::error::Error;
use std::fs;
use std::mem::{self, Discriminant};
use std::path::Path;
use std::process;
use std::sync::Arc;
use std::thread::ThreadId;
use std::u32;
@ -62,6 +62,206 @@ fn thread_id_to_u64(tid: ThreadId) -> u64 {
unsafe { mem::transmute::<ThreadId, u64>(tid) }
}
/// A reference to the SelfProfiler. It can be cloned and sent across thread
/// boundaries at will.
#[derive(Clone)]
pub struct SelfProfilerRef {
// This field is `None` if self-profiling is disabled for the current
// compilation session.
profiler: Option<Arc<SelfProfiler>>,
// We store the filter mask directly in the reference because that doesn't
// cost anything and allows for filtering with checking if the profiler is
// actually enabled.
event_filter_mask: EventFilter,
}
impl SelfProfilerRef {
pub fn new(profiler: Option<Arc<SelfProfiler>>) -> SelfProfilerRef {
// If there is no SelfProfiler then the filter mask is set to NONE,
// ensuring that nothing ever tries to actually access it.
let event_filter_mask = profiler
.as_ref()
.map(|p| p.event_filter_mask)
.unwrap_or(EventFilter::NONE);
SelfProfilerRef {
profiler,
event_filter_mask,
}
}
// This shim makes sure that calls only get executed if the filter mask
// lets them pass. It also contains some trickery to make sure that
// code is optimized for non-profiling compilation sessions, i.e. anything
// past the filter check is never inlined so it doesn't clutter the fast
// path.
#[inline(always)]
fn exec<F>(&self, event_filter: EventFilter, f: F) -> TimingGuard<'_>
where F: for<'a> FnOnce(&'a SelfProfiler) -> TimingGuard<'a>
{
#[inline(never)]
fn cold_call<F>(profiler_ref: &SelfProfilerRef, f: F) -> TimingGuard<'_>
where F: for<'a> FnOnce(&'a SelfProfiler) -> TimingGuard<'a>
{
let profiler = profiler_ref.profiler.as_ref().unwrap();
f(&**profiler)
}
if unlikely!(self.event_filter_mask.contains(event_filter)) {
cold_call(self, f)
} else {
TimingGuard::none()
}
}
/// Start profiling a generic activity. Profiling continues until the
/// TimingGuard returned from this call is dropped.
#[inline(always)]
pub fn generic_activity(&self, event_id: &str) -> TimingGuard<'_> {
self.exec(EventFilter::GENERIC_ACTIVITIES, |profiler| {
let event_id = profiler.profiler.alloc_string(event_id);
TimingGuard::start(
profiler,
profiler.generic_activity_event_kind,
event_id
)
})
}
/// Start profiling a generic activity. Profiling continues until
/// `generic_activity_end` is called. The RAII-based `generic_activity`
/// usually is the better alternative.
#[inline(always)]
pub fn generic_activity_start(&self, event_id: &str) {
self.non_guard_generic_event(
|profiler| profiler.generic_activity_event_kind,
|profiler| profiler.profiler.alloc_string(event_id),
EventFilter::GENERIC_ACTIVITIES,
TimestampKind::Start,
);
}
/// End profiling a generic activity that was started with
/// `generic_activity_start`. The RAII-based `generic_activity` usually is
/// the better alternative.
#[inline(always)]
pub fn generic_activity_end(&self, event_id: &str) {
self.non_guard_generic_event(
|profiler| profiler.generic_activity_event_kind,
|profiler| profiler.profiler.alloc_string(event_id),
EventFilter::GENERIC_ACTIVITIES,
TimestampKind::End,
);
}
/// Start profiling a query provider. Profiling continues until the
/// TimingGuard returned from this call is dropped.
#[inline(always)]
pub fn query_provider(&self, query_name: QueryName) -> TimingGuard<'_> {
self.exec(EventFilter::QUERY_PROVIDERS, |profiler| {
let event_id = SelfProfiler::get_query_name_string_id(query_name);
TimingGuard::start(profiler, profiler.query_event_kind, event_id)
})
}
/// Record a query in-memory cache hit.
#[inline(always)]
pub fn query_cache_hit(&self, query_name: QueryName) {
self.non_guard_query_event(
|profiler| profiler.query_cache_hit_event_kind,
query_name,
EventFilter::QUERY_CACHE_HITS,
TimestampKind::Instant,
);
}
/// Start profiling a query being blocked on a concurrent execution.
/// Profiling continues until `query_blocked_end` is called.
#[inline(always)]
pub fn query_blocked_start(&self, query_name: QueryName) {
self.non_guard_query_event(
|profiler| profiler.query_blocked_event_kind,
query_name,
EventFilter::QUERY_BLOCKED,
TimestampKind::Start,
);
}
/// End profiling a query being blocked on a concurrent execution.
#[inline(always)]
pub fn query_blocked_end(&self, query_name: QueryName) {
self.non_guard_query_event(
|profiler| profiler.query_blocked_event_kind,
query_name,
EventFilter::QUERY_BLOCKED,
TimestampKind::End,
);
}
/// Start profiling how long it takes to load a query result from the
/// incremental compilation on-disk cache. Profiling continues until the
/// TimingGuard returned from this call is dropped.
#[inline(always)]
pub fn incr_cache_loading(&self, query_name: QueryName) -> TimingGuard<'_> {
self.exec(EventFilter::INCR_CACHE_LOADS, |profiler| {
let event_id = SelfProfiler::get_query_name_string_id(query_name);
TimingGuard::start(
profiler,
profiler.incremental_load_result_event_kind,
event_id
)
})
}
#[inline(always)]
fn non_guard_query_event(
&self,
event_kind: fn(&SelfProfiler) -> StringId,
query_name: QueryName,
event_filter: EventFilter,
timestamp_kind: TimestampKind
) {
drop(self.exec(event_filter, |profiler| {
let event_id = SelfProfiler::get_query_name_string_id(query_name);
let thread_id = thread_id_to_u64(std::thread::current().id());
profiler.profiler.record_event(
event_kind(profiler),
event_id,
thread_id,
timestamp_kind,
);
TimingGuard::none()
}));
}
#[inline(always)]
fn non_guard_generic_event<F: FnOnce(&SelfProfiler) -> StringId>(
&self,
event_kind: fn(&SelfProfiler) -> StringId,
event_id: F,
event_filter: EventFilter,
timestamp_kind: TimestampKind
) {
drop(self.exec(event_filter, |profiler| {
let thread_id = thread_id_to_u64(std::thread::current().id());
profiler.profiler.record_event(
event_kind(profiler),
event_id(profiler),
thread_id,
timestamp_kind,
);
TimingGuard::none()
}));
}
}
pub struct SelfProfiler {
profiler: Profiler,
event_filter_mask: EventFilter,
@ -143,103 +343,51 @@ impl SelfProfiler {
let id = SelfProfiler::get_query_name_string_id(query_name);
self.profiler.alloc_string_with_reserved_id(id, query_name.as_str());
}
}
#[must_use]
pub struct TimingGuard<'a>(Option<TimingGuardInternal<'a>>);
struct TimingGuardInternal<'a> {
raw_profiler: &'a Profiler,
event_id: StringId,
event_kind: StringId,
thread_id: u64,
}
impl<'a> TimingGuard<'a> {
#[inline]
pub fn start_activity(
&self,
label: impl Into<Cow<'static, str>>,
) {
if self.event_filter_mask.contains(EventFilter::GENERIC_ACTIVITIES) {
self.record(&label.into(), self.generic_activity_event_kind, TimestampKind::Start);
}
}
#[inline]
pub fn end_activity(
&self,
label: impl Into<Cow<'static, str>>,
) {
if self.event_filter_mask.contains(EventFilter::GENERIC_ACTIVITIES) {
self.record(&label.into(), self.generic_activity_event_kind, TimestampKind::End);
}
}
#[inline]
pub fn record_query_hit(&self, query_name: QueryName) {
if self.event_filter_mask.contains(EventFilter::QUERY_CACHE_HITS) {
self.record_query(query_name, self.query_cache_hit_event_kind, TimestampKind::Instant);
}
}
#[inline]
pub fn start_query(&self, query_name: QueryName) {
if self.event_filter_mask.contains(EventFilter::QUERY_PROVIDERS) {
self.record_query(query_name, self.query_event_kind, TimestampKind::Start);
}
}
#[inline]
pub fn end_query(&self, query_name: QueryName) {
if self.event_filter_mask.contains(EventFilter::QUERY_PROVIDERS) {
self.record_query(query_name, self.query_event_kind, TimestampKind::End);
}
}
#[inline]
pub fn incremental_load_result_start(&self, query_name: QueryName) {
if self.event_filter_mask.contains(EventFilter::INCR_CACHE_LOADS) {
self.record_query(
query_name,
self.incremental_load_result_event_kind,
TimestampKind::Start
);
}
}
#[inline]
pub fn incremental_load_result_end(&self, query_name: QueryName) {
if self.event_filter_mask.contains(EventFilter::INCR_CACHE_LOADS) {
self.record_query(
query_name,
self.incremental_load_result_event_kind,
TimestampKind::End
);
}
}
#[inline]
pub fn query_blocked_start(&self, query_name: QueryName) {
if self.event_filter_mask.contains(EventFilter::QUERY_BLOCKED) {
self.record_query(query_name, self.query_blocked_event_kind, TimestampKind::Start);
}
}
#[inline]
pub fn query_blocked_end(&self, query_name: QueryName) {
if self.event_filter_mask.contains(EventFilter::QUERY_BLOCKED) {
self.record_query(query_name, self.query_blocked_event_kind, TimestampKind::End);
}
}
#[inline]
fn record(&self, event_id: &str, event_kind: StringId, timestamp_kind: TimestampKind) {
let thread_id = thread_id_to_u64(std::thread::current().id());
let event_id = self.profiler.alloc_string(event_id);
self.profiler.record_event(event_kind, event_id, thread_id, timestamp_kind);
}
#[inline]
fn record_query(
&self,
query_name: QueryName,
pub fn start(
profiler: &'a SelfProfiler,
event_kind: StringId,
timestamp_kind: TimestampKind,
) {
let dep_node_name = SelfProfiler::get_query_name_string_id(query_name);
event_id: StringId,
) -> TimingGuard<'a> {
let thread_id = thread_id_to_u64(std::thread::current().id());
let raw_profiler = &profiler.profiler;
raw_profiler.record_event(event_kind, event_id, thread_id, TimestampKind::Start);
self.profiler.record_event(event_kind, dep_node_name, thread_id, timestamp_kind);
TimingGuard(Some(TimingGuardInternal {
raw_profiler,
event_kind,
event_id,
thread_id,
}))
}
#[inline]
pub fn none() -> TimingGuard<'a> {
TimingGuard(None)
}
}
impl<'a> Drop for TimingGuardInternal<'a> {
#[inline]
fn drop(&mut self) {
self.raw_profiler.record_event(
self.event_kind,
self.event_id,
self.thread_id,
TimestampKind::End
);
}
}