Always profile commands and generate Chrome profile when tracing is enabled

Author: Kobzol

src/bootstrap/src/bin/main.rs

@@ -16,19 +16,15 @@ use bootstrap::{
     find_recent_config_change_ids, human_readable_changes, symlink_dir, t,
 };
 
-fn is_profiling_enabled() -> bool {
-    env::var("BOOTSTRAP_PROFILE").is_ok_and(|v| v == "1")
-}
-
 fn is_tracing_enabled() -> bool {
-    is_profiling_enabled() || cfg!(feature = "tracing")
+    cfg!(feature = "tracing")
 }
 
 fn main() {
     #[cfg(feature = "tracing")]
-    let guard = bootstrap::setup_tracing(is_profiling_enabled());
+    let guard = bootstrap::setup_tracing("BOOTSTRAP_TRACING");
 
-    let start_time = Instant::now();
+    let _start_time = Instant::now();
 
     let args = env::args().skip(1).collect::<Vec<_>>();
 
@@ -175,19 +171,11 @@ fn main() {
         }
     }
 
-    if is_profiling_enabled() {
-        build.report_summary(&tracing_dir.join("command-stats.txt"), start_time);
-    }
-
     #[cfg(feature = "tracing")]
     {
+        build.report_summary(&tracing_dir.join("command-stats.txt"), _start_time);
         build.report_step_graph(&tracing_dir);
-        if let Some(guard) = guard {
-            guard.copy_to_dir(&tracing_dir);
-        }
-    }
-
-    if tracing_enabled {
+        guard.copy_to_dir(&tracing_dir);
         eprintln!("Tracing/profiling output has been written to {}", latest_trace_dir.display());
     }
 }

src/bootstrap/src/utils/tracing.rs

@@ -92,50 +92,43 @@ mod inner {
     use crate::STEP_SPAN_TARGET;
     use crate::utils::tracing::COMMAND_SPAN_TARGET;
 
-    pub fn setup_tracing(profiling_enabled: bool) -> Option<TracingGuard> {
-        let filter = EnvFilter::from_env("BOOTSTRAP_TRACING");
+    pub fn setup_tracing(env_name: &str) -> TracingGuard {
+        let filter = EnvFilter::from_env(env_name);
 
         let registry = tracing_subscriber::registry().with(filter).with(TracingPrinter::default());
 
-        let guard = if profiling_enabled {
-            // When we're creating this layer, we do not yet know the location of the tracing output
-            // directory, because it is stored in the output directory determined after Config is parsed,
-            // but we already want to make tracing calls during (and before) config parsing.
-            // So we store the output into a temporary file, and then move it to the tracing directory
-            // before bootstrap ends.
-            let tempdir = tempfile::TempDir::new().expect("Cannot create temporary directory");
-            let chrome_tracing_path = tempdir.path().join("bootstrap-trace.json");
-            let file = std::io::BufWriter::new(File::create(&chrome_tracing_path).unwrap());
-
-            let chrome_layer = tracing_chrome::ChromeLayerBuilder::new()
-                .writer(file)
-                .include_args(true)
-                .name_fn(Box::new(|event_or_span| match event_or_span {
-                    tracing_chrome::EventOrSpan::Event(e) => e.metadata().name().to_string(),
-                    tracing_chrome::EventOrSpan::Span(s) => {
-                        if s.metadata().target() == STEP_SPAN_TARGET
-                            && let Some(extension) = s.extensions().get::<StepNameExtension>()
-                        {
-                            extension.0.clone()
-                        } else if s.metadata().target() == COMMAND_SPAN_TARGET
-                            && let Some(extension) = s.extensions().get::<CommandNameExtension>()
-                        {
-                            extension.0.clone()
-                        } else {
-                            s.metadata().name().to_string()
-                        }
+        // When we're creating this layer, we do not yet know the location of the tracing output
+        // directory, because it is stored in the output directory determined after Config is parsed,
+        // but we already want to make tracing calls during (and before) config parsing.
+        // So we store the output into a temporary file, and then move it to the tracing directory
+        // before bootstrap ends.
+        let tempdir = tempfile::TempDir::new().expect("Cannot create temporary directory");
+        let chrome_tracing_path = tempdir.path().join("bootstrap-trace.json");
+        let file = std::io::BufWriter::new(File::create(&chrome_tracing_path).unwrap());
+
+        let chrome_layer = tracing_chrome::ChromeLayerBuilder::new()
+            .writer(file)
+            .include_args(true)
+            .name_fn(Box::new(|event_or_span| match event_or_span {
+                tracing_chrome::EventOrSpan::Event(e) => e.metadata().name().to_string(),
+                tracing_chrome::EventOrSpan::Span(s) => {
+                    if s.metadata().target() == STEP_SPAN_TARGET
+                        && let Some(extension) = s.extensions().get::<StepNameExtension>()
+                    {
+                        extension.0.clone()
+                    } else if s.metadata().target() == COMMAND_SPAN_TARGET
+                        && let Some(extension) = s.extensions().get::<CommandNameExtension>()
+                    {
+                        extension.0.clone()
+                    } else {
+                        s.metadata().name().to_string()
                     }
-                }));
-            let (chrome_layer, guard) = chrome_layer.build();
-
-            tracing::subscriber::set_global_default(registry.with(chrome_layer)).unwrap();
-            Some(TracingGuard { guard, _tempdir: tempdir, chrome_tracing_path })
-        } else {
-            tracing::subscriber::set_global_default(registry).unwrap();
-            None
-        };
+                }
+            }));
+        let (chrome_layer, guard) = chrome_layer.build();
 
-        guard
+        tracing::subscriber::set_global_default(registry.with(chrome_layer)).unwrap();
+        TracingGuard { guard, _tempdir: tempdir, chrome_tracing_path }
     }
 
     pub struct TracingGuard {