Rollup merge of #64840 - michaelwoerister:self-profiling-raii-refactor, r=wesleywiser

SelfProfiler API refactoring and part one of event review

This PR refactors the `SelfProfiler` a little bit so that most profiling methods are RAII-based. The codegen backend code already had something similar, this refactoring pulls this functionality up into `SelfProfiler` itself, for general use.

The second commit of this PR is a review and update of the existing events we are already recording. Names have been made more consistent. CGU names have been removed from event names. They will be added back in when function parameter recording is implemented.

There is still some work to be done for adding new events, especially around trait resolution and the incremental system.

r? @wesleywiser

3 files changed, 12 insertions, 72 deletions

diff --git a/src/librustc_codegen_ssa/back/write.rs b/src/librustc_codegen_ssa/back/write.rs
index 3c5fbfd0f86..f1cfac27033 100644
--- a/src/librustc_codegen_ssa/back/write.rs
+++ b/src/librustc_codegen_ssa/back/write.rs
@@ -19,7 +19,7 @@ use rustc::util::nodemap::FxHashMap;
 use rustc::hir::def_id::{CrateNum, LOCAL_CRATE};
 use rustc::ty::TyCtxt;
 use rustc::util::common::{time_depth, set_time_depth, print_time_passes_entry};
-use rustc::util::profiling::SelfProfiler;
+use rustc::util::profiling::SelfProfilerRef;
 use rustc_fs_util::link_or_copy;
 use rustc_data_structures::svh::Svh;
 use rustc_errors::{Handler, Level, FatalError, DiagnosticId};
@@ -31,7 +31,6 @@ use syntax_pos::symbol::{Symbol, sym};
 use jobserver::{Client, Acquired};
 
 use std::any::Any;
-use std::borrow::Cow;
 use std::fs;
 use std::io;
 use std::mem;
@@ -196,42 +195,13 @@ impl<B: WriteBackendMethods> Clone for TargetMachineFactory<B> {
     }
 }
 
-pub struct ProfileGenericActivityTimer {
-    profiler: Option<Arc<SelfProfiler>>,
-    label: Cow<'static, str>,
-}
-
-impl ProfileGenericActivityTimer {
-    pub fn start(
-        profiler: Option<Arc<SelfProfiler>>,
-        label: Cow<'static, str>,
-    ) -> ProfileGenericActivityTimer {
-        if let Some(profiler) = &profiler {
-            profiler.start_activity(label.clone());
-        }
-
-        ProfileGenericActivityTimer {
-            profiler,
-            label,
-        }
-    }
-}
-
-impl Drop for ProfileGenericActivityTimer {
-    fn drop(&mut self) {
-        if let Some(profiler) = &self.profiler {
-            profiler.end_activity(self.label.clone());
-        }
-    }
-}
-
 /// Additional resources used by optimize_and_codegen (not module specific)
 #[derive(Clone)]
 pub struct CodegenContext<B: WriteBackendMethods> {
     // Resources needed when running LTO
     pub backend: B,
     pub time_passes: bool,
-    pub profiler: Option<Arc<SelfProfiler>>,
+    pub prof: SelfProfilerRef,
     pub lto: Lto,
     pub no_landing_pads: bool,
     pub save_temps: bool,
@@ -283,31 +253,6 @@ impl<B: WriteBackendMethods> CodegenContext<B> {
             ModuleKind::Allocator => &self.allocator_module_config,
         }
     }
-
-    #[inline(never)]
-    #[cold]
-    fn profiler_active<F: FnOnce(&SelfProfiler) -> ()>(&self, f: F) {
-        match &self.profiler {
-            None => bug!("profiler_active() called but there was no profiler active"),
-            Some(profiler) => {
-                f(&*profiler);
-            }
-        }
-    }
-
-    #[inline(always)]
-    pub fn profile<F: FnOnce(&SelfProfiler) -> ()>(&self, f: F) {
-        if unlikely!(self.profiler.is_some()) {
-            self.profiler_active(f)
-        }
-    }
-
-    pub fn profile_activity(
-        &self,
-        label: impl Into<Cow<'static, str>>,
-    ) -> ProfileGenericActivityTimer {
-        ProfileGenericActivityTimer::start(self.profiler.clone(), label.into())
-    }
 }
 
 fn generate_lto_work<B: ExtraBackendMethods>(
@@ -316,7 +261,7 @@ fn generate_lto_work<B: ExtraBackendMethods>(
     needs_thin_lto: Vec<(String, B::ThinBuffer)>,
     import_only_modules: Vec<(SerializedModule<B::ModuleBuffer>, WorkProduct)>
 ) -> Vec<(WorkItem<B>, u64)> {
-    cgcx.profile(|p| p.start_activity("codegen_run_lto"));
+    let _prof_timer = cgcx.prof.generic_activity("codegen_run_lto");
 
     let (lto_modules, copy_jobs) = if !needs_fat_lto.is_empty() {
         assert!(needs_thin_lto.is_empty());
@@ -343,8 +288,6 @@ fn generate_lto_work<B: ExtraBackendMethods>(
         }), 0)
     })).collect();
 
-    cgcx.profile(|p| p.end_activity("codegen_run_lto"));
-
     result
 }
 
@@ -380,6 +323,9 @@ pub fn start_async_codegen<B: ExtraBackendMethods>(
 ) -> OngoingCodegen<B> {
     let (coordinator_send, coordinator_receive) = channel();
     let sess = tcx.sess;
+
+    sess.prof.generic_activity_start("codegen_and_optimize_crate");
+
     let crate_name = tcx.crate_name(LOCAL_CRATE);
     let crate_hash = tcx.crate_hash(LOCAL_CRATE);
     let no_builtins = attr::contains_name(&tcx.hir().krate().attrs, sym::no_builtins);
@@ -1088,7 +1034,7 @@ fn start_executing_work<B: ExtraBackendMethods>(
         save_temps: sess.opts.cg.save_temps,
         opts: Arc::new(sess.opts.clone()),
         time_passes: sess.time_extended(),
-        profiler: sess.self_profiling.clone(),
+        prof: sess.prof.clone(),
         exported_symbols,
         plugin_passes: sess.plugin_llvm_passes.borrow().clone(),
         remark: sess.opts.cg.remark.clone(),
@@ -1645,12 +1591,8 @@ fn spawn_work<B: ExtraBackendMethods>(
         // as a diagnostic was already sent off to the main thread - just
         // surface that there was an error in this worker.
         bomb.result = {
-            let label = work.name();
-            cgcx.profile(|p| p.start_activity(label.clone()));
-            let result = execute_work_item(&cgcx, work).ok();
-            cgcx.profile(|p| p.end_activity(label));
-
-            result
+            let _prof_timer = cgcx.prof.generic_activity(&work.name());
+            execute_work_item(&cgcx, work).ok()
         };
     });
 }
@@ -1835,6 +1777,8 @@ impl<B: ExtraBackendMethods> OngoingCodegen<B> {
             self.backend.print_pass_timings()
         }
 
+        sess.prof.generic_activity_end("codegen_and_optimize_crate");
+
         (CodegenResults {
             crate_name: self.crate_name,
             crate_hash: self.crate_hash,
diff --git a/src/librustc_codegen_ssa/base.rs b/src/librustc_codegen_ssa/base.rs
index d11d8911a93..935087714a7 100644
--- a/src/librustc_codegen_ssa/base.rs
+++ b/src/librustc_codegen_ssa/base.rs
@@ -559,7 +559,7 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
 
     if need_metadata_module {
         // Codegen the encoded metadata.
-        tcx.sess.profiler(|p| p.start_activity("codegen crate metadata"));
+        let _prof_timer = tcx.prof.generic_activity("codegen_crate_metadata");
 
         let metadata_cgu_name = cgu_name_builder.build_cgu_name(LOCAL_CRATE,
                                                                 &["crate"],
@@ -570,7 +570,6 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
             backend.write_compressed_metadata(tcx, &ongoing_codegen.metadata,
                                               &mut metadata_llvm_module);
         });
-        tcx.sess.profiler(|p| p.end_activity("codegen crate metadata"));
 
         let metadata_module = ModuleCodegen {
             name: metadata_cgu_name,
@@ -599,11 +598,9 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
 
         match cgu_reuse {
             CguReuse::No => {
-                tcx.sess.profiler(|p| p.start_activity(format!("codegen {}", cgu.name())));
                 let start_time = Instant::now();
                 backend.compile_codegen_unit(tcx, *cgu.name(), &ongoing_codegen.coordinator_send);
                 total_codegen_time += start_time.elapsed();
-                tcx.sess.profiler(|p| p.end_activity(format!("codegen {}", cgu.name())));
                 false
             }
             CguReuse::PreLto => {
diff --git a/src/librustc_codegen_ssa/lib.rs b/src/librustc_codegen_ssa/lib.rs
index 161d3ce61f0..5017a60ca69 100644
--- a/src/librustc_codegen_ssa/lib.rs
+++ b/src/librustc_codegen_ssa/lib.rs
@@ -21,7 +21,6 @@
 
 #[macro_use] extern crate log;
 #[macro_use] extern crate rustc;
-#[macro_use] extern crate rustc_data_structures;
 #[macro_use] extern crate syntax;
 
 use std::path::PathBuf;