Merge pull request #19142 from Veykril/push-upwqztrsuwpz

Spawn toolchain querying processes in parallel

crates/project-model/src/lib.rs

@@ -260,19 +260,19 @@ fn parse_cfg(s: &str) -> Result<cfg::CfgAtom, String> {
 }
 
 #[derive(Clone, Debug, PartialEq, Eq)]
-pub enum SysrootSourceWorkspaceConfig {
+pub enum RustSourceWorkspaceConfig {
     CargoMetadata(CargoMetadataConfig),
     Stitched,
 }
 
-impl Default for SysrootSourceWorkspaceConfig {
+impl Default for RustSourceWorkspaceConfig {
     fn default() -> Self {
-        SysrootSourceWorkspaceConfig::default_cargo()
+        RustSourceWorkspaceConfig::default_cargo()
     }
 }
 
-impl SysrootSourceWorkspaceConfig {
+impl RustSourceWorkspaceConfig {
     pub fn default_cargo() -> Self {
-        SysrootSourceWorkspaceConfig::CargoMetadata(Default::default())
+        RustSourceWorkspaceConfig::CargoMetadata(Default::default())
     }
 }

crates/project-model/src/sysroot.rs

@@ -22,38 +22,40 @@ use toolchain::{probe_for_binary, Tool};
 
 use crate::{
     cargo_workspace::CargoMetadataConfig, utf8_stdout, CargoWorkspace, ManifestPath,
-    SysrootSourceWorkspaceConfig,
+    RustSourceWorkspaceConfig,
 };
 
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct Sysroot {
     root: Option<AbsPathBuf>,
-    src_root: Option<AbsPathBuf>,
-    workspace: SysrootWorkspace,
+    rust_lib_src_root: Option<AbsPathBuf>,
+    workspace: RustLibSrcWorkspace,
     error: Option<String>,
 }
 
 #[derive(Debug, Clone, Eq, PartialEq)]
-pub(crate) enum SysrootWorkspace {
+pub enum RustLibSrcWorkspace {
     Workspace(CargoWorkspace),
     Stitched(Stitched),
     Empty,
 }
 
 #[derive(Debug, Clone, Eq, PartialEq)]
-pub(crate) struct Stitched {
-    crates: Arena<SysrootCrateData>,
+pub struct Stitched {
+    crates: Arena<RustLibSrcCrateData>,
 }
 
-impl ops::Index<SysrootCrate> for Stitched {
-    type Output = SysrootCrateData;
-    fn index(&self, index: SysrootCrate) -> &SysrootCrateData {
+impl ops::Index<RustLibSrcCrate> for Stitched {
+    type Output = RustLibSrcCrateData;
+    fn index(&self, index: RustLibSrcCrate) -> &RustLibSrcCrateData {
         &self.crates[index]
     }
 }
 
 impl Stitched {
-    pub(crate) fn public_deps(&self) -> impl Iterator<Item = (CrateName, SysrootCrate, bool)> + '_ {
+    pub(crate) fn public_deps(
+        &self,
+    ) -> impl Iterator<Item = (CrateName, RustLibSrcCrate, bool)> + '_ {
         // core is added as a dependency before std in order to
         // mimic rustcs dependency order
         [("core", true), ("alloc", false), ("std", true), ("test", false)].into_iter().filter_map(
@@ -63,32 +65,37 @@ impl Stitched {
         )
     }
 
-    pub(crate) fn proc_macro(&self) -> Option<SysrootCrate> {
+    pub(crate) fn proc_macro(&self) -> Option<RustLibSrcCrate> {
         self.by_name("proc_macro")
     }
 
-    pub(crate) fn crates(&self) -> impl ExactSizeIterator<Item = SysrootCrate> + '_ {
+    pub(crate) fn crates(&self) -> impl ExactSizeIterator<Item = RustLibSrcCrate> + '_ {
         self.crates.iter().map(|(id, _data)| id)
     }
 
-    fn by_name(&self, name: &str) -> Option<SysrootCrate> {
+    fn by_name(&self, name: &str) -> Option<RustLibSrcCrate> {
         let (id, _data) = self.crates.iter().find(|(_id, data)| data.name == name)?;
         Some(id)
     }
 }
 
-pub(crate) type SysrootCrate = Idx<SysrootCrateData>;
+pub(crate) type RustLibSrcCrate = Idx<RustLibSrcCrateData>;
 
 #[derive(Debug, Clone, Eq, PartialEq)]
-pub(crate) struct SysrootCrateData {
+pub(crate) struct RustLibSrcCrateData {
     pub(crate) name: String,
     pub(crate) root: ManifestPath,
-    pub(crate) deps: Vec<SysrootCrate>,
+    pub(crate) deps: Vec<RustLibSrcCrate>,
 }
 
 impl Sysroot {
     pub const fn empty() -> Sysroot {
-        Sysroot { root: None, src_root: None, workspace: SysrootWorkspace::Empty, error: None }
+        Sysroot {
+            root: None,
+            rust_lib_src_root: None,
+            workspace: RustLibSrcWorkspace::Empty,
+            error: None,
+        }
     }
 
     /// Returns sysroot "root" directory, where `bin/`, `etc/`, `lib/`, `libexec/`
@@ -100,15 +107,15 @@ impl Sysroot {
 
     /// Returns the sysroot "source" directory, where stdlib sources are located, like:
     /// `$HOME/.rustup/toolchains/nightly-2022-07-23-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library`
-    pub fn src_root(&self) -> Option<&AbsPath> {
-        self.src_root.as_deref()
+    pub fn rust_lib_src_root(&self) -> Option<&AbsPath> {
+        self.rust_lib_src_root.as_deref()
     }
 
-    pub fn is_empty(&self) -> bool {
+    pub fn is_rust_lib_src_empty(&self) -> bool {
         match &self.workspace {
-            SysrootWorkspace::Workspace(ws) => ws.packages().next().is_none(),
-            SysrootWorkspace::Stitched(stitched) => stitched.crates.is_empty(),
-            SysrootWorkspace::Empty => true,
+            RustLibSrcWorkspace::Workspace(ws) => ws.packages().next().is_none(),
+            RustLibSrcWorkspace::Stitched(stitched) => stitched.crates.is_empty(),
+            RustLibSrcWorkspace::Empty => true,
         }
     }
 
@@ -118,13 +125,13 @@ impl Sysroot {
 
     pub fn num_packages(&self) -> usize {
         match &self.workspace {
-            SysrootWorkspace::Workspace(ws) => ws.packages().count(),
-            SysrootWorkspace::Stitched(c) => c.crates().count(),
-            SysrootWorkspace::Empty => 0,
+            RustLibSrcWorkspace::Workspace(ws) => ws.packages().count(),
+            RustLibSrcWorkspace::Stitched(c) => c.crates().count(),
+            RustLibSrcWorkspace::Empty => 0,
         }
     }
 
-    pub(crate) fn workspace(&self) -> &SysrootWorkspace {
+    pub(crate) fn workspace(&self) -> &RustLibSrcWorkspace {
         &self.workspace
     }
 }
@@ -133,33 +140,33 @@ impl Sysroot {
     /// Attempts to discover the toolchain's sysroot from the given `dir`.
     pub fn discover(dir: &AbsPath, extra_env: &FxHashMap<String, String>) -> Sysroot {
         let sysroot_dir = discover_sysroot_dir(dir, extra_env);
-        let sysroot_src_dir = sysroot_dir.as_ref().ok().map(|sysroot_dir| {
-            discover_sysroot_src_dir_or_add_component(sysroot_dir, dir, extra_env)
+        let rust_lib_src_dir = sysroot_dir.as_ref().ok().map(|sysroot_dir| {
+            discover_rust_lib_src_dir_or_add_component(sysroot_dir, dir, extra_env)
         });
-        Sysroot::assemble(Some(sysroot_dir), sysroot_src_dir)
+        Sysroot::assemble(Some(sysroot_dir), rust_lib_src_dir)
     }
 
     pub fn discover_with_src_override(
         current_dir: &AbsPath,
         extra_env: &FxHashMap<String, String>,
-        sysroot_src_dir: AbsPathBuf,
+        rust_lib_src_dir: AbsPathBuf,
     ) -> Sysroot {
         let sysroot_dir = discover_sysroot_dir(current_dir, extra_env);
-        Sysroot::assemble(Some(sysroot_dir), Some(Ok(sysroot_src_dir)))
+        Sysroot::assemble(Some(sysroot_dir), Some(Ok(rust_lib_src_dir)))
     }
 
-    pub fn discover_sysroot_src_dir(sysroot_dir: AbsPathBuf) -> Sysroot {
-        let sysroot_src_dir = discover_sysroot_src_dir(&sysroot_dir)
+    pub fn discover_rust_lib_src_dir(sysroot_dir: AbsPathBuf) -> Sysroot {
+        let rust_lib_src_dir = discover_rust_lib_src_dir(&sysroot_dir)
             .ok_or_else(|| format_err!("can't find standard library sources in {sysroot_dir}"));
-        Sysroot::assemble(Some(Ok(sysroot_dir)), Some(sysroot_src_dir))
+        Sysroot::assemble(Some(Ok(sysroot_dir)), Some(rust_lib_src_dir))
     }
 
     pub fn discover_rustc_src(&self) -> Option<ManifestPath> {
         get_rustc_src(self.root()?)
     }
 
-    pub fn new(sysroot_dir: Option<AbsPathBuf>, sysroot_src_dir: Option<AbsPathBuf>) -> Sysroot {
-        Self::assemble(sysroot_dir.map(Ok), sysroot_src_dir.map(Ok))
+    pub fn new(sysroot_dir: Option<AbsPathBuf>, rust_lib_src_dir: Option<AbsPathBuf>) -> Sysroot {
+        Self::assemble(sysroot_dir.map(Ok), rust_lib_src_dir.map(Ok))
     }
 
     /// Returns a command to run a tool preferring the cargo proxies if the sysroot exists.
@@ -200,7 +207,7 @@ impl Sysroot {
 
     fn assemble(
         sysroot_dir: Option<Result<AbsPathBuf, anyhow::Error>>,
-        sysroot_src_dir: Option<Result<AbsPathBuf, anyhow::Error>>,
+        rust_lib_src_dir: Option<Result<AbsPathBuf, anyhow::Error>>,
     ) -> Sysroot {
         let mut errors = String::new();
         let root = match sysroot_dir {
@@ -211,8 +218,8 @@ impl Sysroot {
             }
             None => None,
         };
-        let src_root = match sysroot_src_dir {
-            Some(Ok(sysroot_src_dir)) => Some(sysroot_src_dir),
+        let rust_lib_src_root = match rust_lib_src_dir {
+            Some(Ok(rust_lib_src_dir)) => Some(rust_lib_src_dir),
             Some(Err(e)) => {
                 format_to!(errors, "{e}\n");
                 None
@@ -221,24 +228,28 @@ impl Sysroot {
         };
         Sysroot {
             root,
-            src_root,
-            workspace: SysrootWorkspace::Empty,
+            rust_lib_src_root,
+            workspace: RustLibSrcWorkspace::Empty,
             error: errors.is_empty().not().then_some(errors),
         }
     }
 
-    pub fn load_workspace(&mut self, sysroot_source_config: &SysrootSourceWorkspaceConfig) {
-        assert!(matches!(self.workspace, SysrootWorkspace::Empty), "workspace already loaded");
-        let Self { root: _, src_root: Some(src_root), workspace, error: _ } = self else { return };
-        if let SysrootSourceWorkspaceConfig::CargoMetadata(cargo_config) = sysroot_source_config {
+    pub fn load_workspace(
+        &self,
+        sysroot_source_config: &RustSourceWorkspaceConfig,
+    ) -> Option<RustLibSrcWorkspace> {
+        assert!(matches!(self.workspace, RustLibSrcWorkspace::Empty), "workspace already loaded");
+        let Self { root: _, rust_lib_src_root: Some(src_root), workspace: _, error: _ } = self
+        else {
+            return None;
+        };
+        if let RustSourceWorkspaceConfig::CargoMetadata(cargo_config) = sysroot_source_config {
             let library_manifest = ManifestPath::try_from(src_root.join("Cargo.toml")).unwrap();
             if fs::metadata(&library_manifest).is_ok() {
                 if let Some(loaded) =
                     Self::load_library_via_cargo(library_manifest, src_root, cargo_config)
                 {
-                    *workspace = loaded;
-                    self.load_core_check();
-                    return;
+                    return Some(loaded);
                 }
             }
         }
@@ -255,7 +266,7 @@ impl Sysroot {
                 .find(|it| fs::metadata(it).is_ok());
 
             if let Some(root) = root {
-                stitched.crates.alloc(SysrootCrateData {
+                stitched.crates.alloc(RustLibSrcCrateData {
                     name: name.into(),
                     root,
                     deps: Vec::new(),
@@ -286,21 +297,23 @@ impl Sysroot {
                 }
             }
         }
-        *workspace = SysrootWorkspace::Stitched(stitched);
-        self.load_core_check();
+        Some(RustLibSrcWorkspace::Stitched(stitched))
     }
 
-    fn load_core_check(&mut self) {
+    pub fn set_workspace(&mut self, workspace: RustLibSrcWorkspace) {
+        self.workspace = workspace;
         if self.error.is_none() {
-            if let Some(src_root) = &self.src_root {
+            if let Some(src_root) = &self.rust_lib_src_root {
                 let has_core = match &self.workspace {
-                    SysrootWorkspace::Workspace(ws) => ws.packages().any(|p| ws[p].name == "core"),
-                    SysrootWorkspace::Stitched(stitched) => stitched.by_name("core").is_some(),
-                    SysrootWorkspace::Empty => true,
+                    RustLibSrcWorkspace::Workspace(ws) => {
+                        ws.packages().any(|p| ws[p].name == "core")
+                    }
+                    RustLibSrcWorkspace::Stitched(stitched) => stitched.by_name("core").is_some(),
+                    RustLibSrcWorkspace::Empty => true,
                 };
                 if !has_core {
-                    let var_note = if env::var_os("RUST_SRC_PATH").is_some() {
-                        " (env var `RUST_SRC_PATH` is set and may be incorrect, try unsetting it)"
+                    let var_note = if env::var_os("rust_lib_src_PATH").is_some() {
+                        " (env var `rust_lib_src_PATH` is set and may be incorrect, try unsetting it)"
                     } else {
                         ", try running `rustup component add rust-src` to possibly fix this"
                     };
@@ -314,9 +327,9 @@ impl Sysroot {
 
     fn load_library_via_cargo(
         library_manifest: ManifestPath,
-        sysroot_src_dir: &AbsPathBuf,
+        rust_lib_src_dir: &AbsPathBuf,
         cargo_config: &CargoMetadataConfig,
-    ) -> Option<SysrootWorkspace> {
+    ) -> Option<RustLibSrcWorkspace> {
         tracing::debug!("Loading library metadata: {library_manifest}");
         let mut cargo_config = cargo_config.clone();
         // the sysroot uses `public-dependency`, so we make cargo think it's a nightly
@@ -327,7 +340,7 @@ impl Sysroot {
 
         let (mut res, _) = match CargoWorkspace::fetch_metadata(
             &library_manifest,
-            sysroot_src_dir,
+            rust_lib_src_dir,
             &cargo_config,
             &Sysroot::empty(),
             // Make sure we never attempt to write to the sysroot
@@ -391,7 +404,7 @@ impl Sysroot {
         });
 
         let cargo_workspace = CargoWorkspace::new(res, library_manifest, Default::default());
-        Some(SysrootWorkspace::Workspace(cargo_workspace))
+        Some(RustLibSrcWorkspace::Workspace(cargo_workspace))
     }
 }
 
@@ -407,36 +420,38 @@ fn discover_sysroot_dir(
     Ok(AbsPathBuf::assert(Utf8PathBuf::from(stdout)))
 }
 
-fn discover_sysroot_src_dir(sysroot_path: &AbsPathBuf) -> Option<AbsPathBuf> {
-    if let Ok(path) = env::var("RUST_SRC_PATH") {
+fn discover_rust_lib_src_dir(sysroot_path: &AbsPathBuf) -> Option<AbsPathBuf> {
+    if let Ok(path) = env::var("rust_lib_src_PATH") {
         if let Ok(path) = AbsPathBuf::try_from(path.as_str()) {
             let core = path.join("core");
             if fs::metadata(&core).is_ok() {
-                tracing::debug!("Discovered sysroot by RUST_SRC_PATH: {path}");
+                tracing::debug!("Discovered sysroot by rust_lib_src_PATH: {path}");
                 return Some(path);
             }
-            tracing::debug!("RUST_SRC_PATH is set, but is invalid (no core: {core:?}), ignoring");
+            tracing::debug!(
+                "rust_lib_src_PATH is set, but is invalid (no core: {core:?}), ignoring"
+            );
         } else {
-            tracing::debug!("RUST_SRC_PATH is set, but is invalid, ignoring");
+            tracing::debug!("rust_lib_src_PATH is set, but is invalid, ignoring");
         }
     }
 
-    get_rust_src(sysroot_path)
+    get_rust_lib_src(sysroot_path)
 }
 
-fn discover_sysroot_src_dir_or_add_component(
+fn discover_rust_lib_src_dir_or_add_component(
     sysroot_path: &AbsPathBuf,
     current_dir: &AbsPath,
     extra_env: &FxHashMap<String, String>,
 ) -> Result<AbsPathBuf> {
-    discover_sysroot_src_dir(sysroot_path)
+    discover_rust_lib_src_dir(sysroot_path)
         .or_else(|| {
             let mut rustup = toolchain::command(Tool::Rustup.prefer_proxy(), current_dir);
             rustup.envs(extra_env);
             rustup.args(["component", "add", "rust-src"]);
             tracing::info!("adding rust-src component by {:?}", rustup);
             utf8_stdout(&mut rustup).ok()?;
-            get_rust_src(sysroot_path)
+            get_rust_lib_src(sysroot_path)
         })
         .ok_or_else(|| {
             tracing::error!(%sysroot_path, "can't load standard library, try installing `rust-src`");
@@ -461,11 +476,11 @@ fn get_rustc_src(sysroot_path: &AbsPath) -> Option<ManifestPath> {
     }
 }
 
-fn get_rust_src(sysroot_path: &AbsPath) -> Option<AbsPathBuf> {
-    let rust_src = sysroot_path.join("lib/rustlib/src/rust/library");
-    tracing::debug!("checking sysroot library: {rust_src}");
-    if fs::metadata(&rust_src).is_ok() {
-        Some(rust_src)
+fn get_rust_lib_src(sysroot_path: &AbsPath) -> Option<AbsPathBuf> {
+    let rust_lib_src = sysroot_path.join("lib/rustlib/src/rust/library");
+    tracing::debug!("checking sysroot library: {rust_lib_src}");
+    if fs::metadata(&rust_lib_src).is_ok() {
+        Some(rust_lib_src)
     } else {
         None
     }

crates/project-model/src/tests.rs

@@ -12,9 +12,9 @@ use span::FileId;
 use triomphe::Arc;
 
 use crate::{
-    sysroot::SysrootWorkspace, workspace::ProjectWorkspaceKind, CargoWorkspace, CfgOverrides,
-    ManifestPath, ProjectJson, ProjectJsonData, ProjectWorkspace, Sysroot,
-    SysrootSourceWorkspaceConfig, WorkspaceBuildScripts,
+    sysroot::RustLibSrcWorkspace, workspace::ProjectWorkspaceKind, CargoWorkspace, CfgOverrides,
+    ManifestPath, ProjectJson, ProjectJsonData, ProjectWorkspace, RustSourceWorkspaceConfig,
+    Sysroot, WorkspaceBuildScripts,
 };
 
 fn load_cargo(file: &str) -> (CrateGraph, ProcMacroPaths) {
@@ -125,7 +125,10 @@ fn get_fake_sysroot() -> Sysroot {
     let sysroot_dir = AbsPathBuf::assert(sysroot_path);
     let sysroot_src_dir = sysroot_dir.clone();
     let mut sysroot = Sysroot::new(Some(sysroot_dir), Some(sysroot_src_dir));
-    sysroot.load_workspace(&SysrootSourceWorkspaceConfig::default_cargo());
+    let loaded_sysroot = sysroot.load_workspace(&RustSourceWorkspaceConfig::default_cargo());
+    if let Some(loaded_sysroot) = loaded_sysroot {
+        sysroot.set_workspace(loaded_sysroot);
+    }
     sysroot
 }
 
@@ -271,8 +274,11 @@ fn smoke_test_real_sysroot_cargo() {
         AbsPath::assert(Utf8Path::new(env!("CARGO_MANIFEST_DIR"))),
         &Default::default(),
     );
-    sysroot.load_workspace(&SysrootSourceWorkspaceConfig::default_cargo());
-    assert!(matches!(sysroot.workspace(), SysrootWorkspace::Workspace(_)));
+    let loaded_sysroot = sysroot.load_workspace(&RustSourceWorkspaceConfig::default_cargo());
+    if let Some(loaded_sysroot) = loaded_sysroot {
+        sysroot.set_workspace(loaded_sysroot);
+    }
+    assert!(matches!(sysroot.workspace(), RustLibSrcWorkspace::Workspace(_)));
     let project_workspace = ProjectWorkspace {
         kind: ProjectWorkspaceKind::Cargo {
             cargo: cargo_workspace,

crates/project-model/src/workspace.rs

@@ -2,7 +2,7 @@
 //! metadata` or `rust-project.json`) into representation stored in the salsa
 //! database -- `CrateGraph`.
 
-use std::{collections::VecDeque, fmt, fs, iter, ops::Deref, sync};
+use std::{collections::VecDeque, fmt, fs, iter, ops::Deref, sync, thread};
 
 use anyhow::Context;
 use base_db::{
@@ -23,10 +23,10 @@ use crate::{
     cargo_workspace::{CargoMetadataConfig, DepKind, PackageData, RustLibSource},
     env::{cargo_config_env, inject_cargo_env, inject_cargo_package_env, inject_rustc_tool_env},
     project_json::{Crate, CrateArrayIdx},
-    sysroot::{SysrootCrate, SysrootWorkspace},
+    sysroot::{RustLibSrcCrate, RustLibSrcWorkspace},
     toolchain_info::{rustc_cfg, target_data_layout, target_tuple, version, QueryConfig},
     CargoConfig, CargoWorkspace, CfgOverrides, InvocationStrategy, ManifestPath, Package,
-    ProjectJson, ProjectManifest, Sysroot, SysrootSourceWorkspaceConfig, TargetData, TargetKind,
+    ProjectJson, ProjectManifest, RustSourceWorkspaceConfig, Sysroot, TargetData, TargetKind,
     WorkspaceBuildScripts,
 };
 use tracing::{debug, error, info};
@@ -186,7 +186,7 @@ impl ProjectWorkspace {
                 let project_location = project_json.parent().to_path_buf();
                 let project_json: ProjectJson =
                     ProjectJson::new(Some(project_json.clone()), &project_location, data);
-                ProjectWorkspace::load_inline(project_json, config)
+                ProjectWorkspace::load_inline(project_json, config, progress)
             }
             ProjectManifest::CargoScript(rust_file) => {
                 ProjectWorkspace::load_detached_file(rust_file, config)?
@@ -204,19 +204,33 @@ impl ProjectWorkspace {
         config: &CargoConfig,
         progress: &dyn Fn(String),
     ) -> Result<ProjectWorkspace, anyhow::Error> {
-        let mut sysroot = match (&config.sysroot, &config.sysroot_src) {
+        progress("Discovering sysroot".to_owned());
+        let CargoConfig {
+            features,
+            rustc_source,
+            extra_args,
+            extra_env,
+            set_test,
+            cfg_overrides,
+            extra_includes,
+            sysroot,
+            sysroot_src,
+            target,
+            ..
+        } = config;
+        let mut sysroot = match (sysroot, sysroot_src) {
             (Some(RustLibSource::Discover), None) => {
-                Sysroot::discover(cargo_toml.parent(), &config.extra_env)
+                Sysroot::discover(cargo_toml.parent(), extra_env)
             }
             (Some(RustLibSource::Discover), Some(sysroot_src)) => {
                 Sysroot::discover_with_src_override(
                     cargo_toml.parent(),
-                    &config.extra_env,
+                    extra_env,
                     sysroot_src.clone(),
                 )
             }
             (Some(RustLibSource::Path(path)), None) => {
-                Sysroot::discover_sysroot_src_dir(path.clone())
+                Sysroot::discover_rust_lib_src_dir(path.clone())
             }
             (Some(RustLibSource::Path(sysroot)), Some(sysroot_src)) => {
                 Sysroot::new(Some(sysroot.clone()), Some(sysroot_src.clone()))
@@ -224,100 +238,147 @@ impl ProjectWorkspace {
             (None, _) => Sysroot::empty(),
         };
 
-        let rustc_dir = match &config.rustc_source {
-            Some(RustLibSource::Path(path)) => ManifestPath::try_from(path.clone())
-                .map_err(|p| Some(format!("rustc source path is not absolute: {p}"))),
-            Some(RustLibSource::Discover) => sysroot
-                .discover_rustc_src()
-                .ok_or_else(|| Some("Failed to discover rustc source for sysroot.".to_owned())),
-            None => Err(None),
-        };
-
-        tracing::info!(workspace = %cargo_toml, src_root = ?sysroot.src_root(), root = ?sysroot.root(), "Using sysroot");
+        tracing::info!(workspace = %cargo_toml, src_root = ?sysroot.rust_lib_src_root(), root = ?sysroot.root(), "Using sysroot");
+        progress("Querying project metadata".to_owned());
         let toolchain_config = QueryConfig::Cargo(&sysroot, cargo_toml);
         let targets =
-            target_tuple::get(toolchain_config, config.target.as_deref(), &config.extra_env)
-                .unwrap_or_default();
-        let toolchain = version::get(toolchain_config, &config.extra_env)
-            .inspect_err(|e| {
-                tracing::error!(%e,
-                    "failed fetching toolchain version for {cargo_toml:?} workspace"
-                )
-            })
-            .ok()
-            .flatten();
-        let rustc_cfg =
-            rustc_cfg::get(toolchain_config, targets.first().map(Deref::deref), &config.extra_env);
-        let cfg_overrides = config.cfg_overrides.clone();
-        let data_layout = target_data_layout::get(
-            toolchain_config,
-            targets.first().map(Deref::deref),
-            &config.extra_env,
-        );
-        if let Err(e) = &data_layout {
-            tracing::error!(%e, "failed fetching data layout for {cargo_toml:?} workspace");
-        }
-        sysroot.load_workspace(&SysrootSourceWorkspaceConfig::CargoMetadata(
-            sysroot_metadata_config(&config.extra_env, &targets),
-        ));
+            target_tuple::get(toolchain_config, target.as_deref(), extra_env).unwrap_or_default();
 
-        let rustc = rustc_dir.and_then(|rustc_dir| {
-            info!(workspace = %cargo_toml, rustc_dir = %rustc_dir, "Using rustc source");
-            match CargoWorkspace::fetch_metadata(
-                &rustc_dir,
-                cargo_toml.parent(),
-                &CargoMetadataConfig {
-                    features: crate::CargoFeatures::default(),
-                    targets: targets.clone(),
-                    extra_args: config.extra_args.clone(),
-                    extra_env: config.extra_env.clone(),
-                },
-                &sysroot,
-                false,
-                progress,
-            ) {
-                Ok((meta, _error)) => {
-                    let workspace = CargoWorkspace::new(meta, cargo_toml.clone(), Env::default());
-                    let build_scripts = WorkspaceBuildScripts::rustc_crates(
-                        &workspace,
-                        cargo_toml.parent(),
-                        &config.extra_env,
+        // We spawn a bunch of processes to query various information about the workspace's
+        // toolchain and sysroot
+        // We can speed up loading a bit by spawning all of these processes in parallel (especially
+        // on systems were process spawning is delayed)
+        let join = thread::scope(|s| {
+            let workspace_dir = cargo_toml.parent();
+            let toolchain = s.spawn(|| {
+                version::get(toolchain_config, extra_env)
+                    .inspect_err(|e| {
+                        tracing::error!(%e,
+                            "failed fetching toolchain version for {cargo_toml:?} workspace"
+                        )
+                    })
+                    .ok()
+                    .flatten()
+            });
+
+            let rustc_cfg = s.spawn(|| {
+                rustc_cfg::get(toolchain_config, targets.first().map(Deref::deref), extra_env)
+            });
+            let data_layout = s.spawn(|| {
+                target_data_layout::get(
+                    toolchain_config,
+                    targets.first().map(Deref::deref),
+                    extra_env,
+                ).inspect_err(|e| {
+                    tracing::error!(%e, "failed fetching data layout for {cargo_toml:?} workspace")
+                })
+            });
+
+            let rustc_dir = s.spawn(|| {
+                let rustc_dir = match rustc_source {
+                    Some(RustLibSource::Path(path)) => ManifestPath::try_from(path.clone())
+                        .map_err(|p| Some(format!("rustc source path is not absolute: {p}"))),
+                    Some(RustLibSource::Discover) => {
+                        sysroot.discover_rustc_src().ok_or_else(|| {
+                            Some("Failed to discover rustc source for sysroot.".to_owned())
+                        })
+                    }
+                    None => Err(None),
+                };
+                rustc_dir.and_then(|rustc_dir| {
+                    info!(workspace = %cargo_toml, rustc_dir = %rustc_dir, "Using rustc source");
+                    match CargoWorkspace::fetch_metadata(
+                        &rustc_dir,
+                        workspace_dir,
+                        &CargoMetadataConfig {
+                            features: crate::CargoFeatures::default(),
+                            targets: targets.clone(),
+                            extra_args: extra_args.clone(),
+                            extra_env: extra_env.clone(),
+                        },
                         &sysroot,
-                    );
-                    Ok(Box::new((workspace, build_scripts)))
-                }
-                Err(e) => {
-                    tracing::error!(
-                        %e,
-                        "Failed to read Cargo metadata from rustc source at {rustc_dir}",
-                    );
-                    Err(Some(format!(
-                        "Failed to read Cargo metadata from rustc source at {rustc_dir}: {e}"
-                    )))
-                }
-            }
+                        false,
+                        &|_| (),
+                    ) {
+                        Ok((meta, _error)) => {
+                            let workspace =
+                                CargoWorkspace::new(meta, cargo_toml.clone(), Env::default());
+                            let build_scripts = WorkspaceBuildScripts::rustc_crates(
+                                &workspace,
+                                workspace_dir,
+                                extra_env,
+                                &sysroot,
+                            );
+                            Ok(Box::new((workspace, build_scripts)))
+                        }
+                        Err(e) => {
+                            tracing::error!(
+                                %e,
+                                "Failed to read Cargo metadata from rustc source at {rustc_dir}",
+                            );
+                            Err(Some(format!(
+                            "Failed to read Cargo metadata from rustc source at {rustc_dir}: {e}"
+                        )))
+                        }
+                    }
+                })
+            });
+
+            let cargo_metadata = s.spawn(|| {
+                CargoWorkspace::fetch_metadata(
+                    cargo_toml,
+                    workspace_dir,
+                    &CargoMetadataConfig {
+                        features: features.clone(),
+                        targets: targets.clone(),
+                        extra_args: extra_args.clone(),
+                        extra_env: extra_env.clone(),
+                    },
+                    &sysroot,
+                    false,
+                    &|_| (),
+                )
+            });
+            let loaded_sysroot = s.spawn(|| {
+                sysroot.load_workspace(&RustSourceWorkspaceConfig::CargoMetadata(
+                    sysroot_metadata_config(extra_env, &targets),
+                ))
+            });
+            let cargo_config_extra_env =
+                s.spawn(|| cargo_config_env(cargo_toml, extra_env, &sysroot));
+            thread::Result::Ok((
+                toolchain.join()?,
+                rustc_cfg.join()?,
+                data_layout.join()?,
+                rustc_dir.join()?,
+                loaded_sysroot.join()?,
+                cargo_metadata.join()?,
+                cargo_config_extra_env.join()?,
+            ))
         });
 
-        let (meta, error) = CargoWorkspace::fetch_metadata(
-            cargo_toml,
-            cargo_toml.parent(),
-            &CargoMetadataConfig {
-                features: config.features.clone(),
-                targets,
-                extra_args: config.extra_args.clone(),
-                extra_env: config.extra_env.clone(),
-            },
-            &sysroot,
-            false,
-            progress,
-        )
-        .with_context(|| {
+        let (
+            toolchain,
+            rustc_cfg,
+            data_layout,
+            rustc,
+            loaded_sysroot,
+            cargo_metadata,
+            cargo_config_extra_env,
+        ) = match join {
+            Ok(it) => it,
+            Err(e) => std::panic::resume_unwind(e),
+        };
+
+        let (meta, error) = cargo_metadata.with_context(|| {
             format!(
                 "Failed to read Cargo metadata from Cargo.toml file {cargo_toml}, {toolchain:?}",
             )
         })?;
-        let cargo_config_extra_env = cargo_config_env(cargo_toml, &config.extra_env, &sysroot);
         let cargo = CargoWorkspace::new(meta, cargo_toml.clone(), cargo_config_extra_env);
+        if let Some(loaded_sysroot) = loaded_sysroot {
+            sysroot.set_workspace(loaded_sysroot);
+        }
 
         Ok(ProjectWorkspace {
             kind: ProjectWorkspaceKind::Cargo {
@@ -325,33 +386,67 @@ impl ProjectWorkspace {
                 build_scripts: WorkspaceBuildScripts::default(),
                 rustc,
                 error: error.map(Arc::new),
-                set_test: config.set_test,
+                set_test: *set_test,
             },
             sysroot,
             rustc_cfg,
-            cfg_overrides,
+            cfg_overrides: cfg_overrides.clone(),
             toolchain,
             target_layout: data_layout.map(Arc::from).map_err(|it| Arc::from(it.to_string())),
-            extra_includes: config.extra_includes.clone(),
+            extra_includes: extra_includes.clone(),
         })
     }
 
-    pub fn load_inline(project_json: ProjectJson, config: &CargoConfig) -> ProjectWorkspace {
+    pub fn load_inline(
+        project_json: ProjectJson,
+        config: &CargoConfig,
+        progress: &dyn Fn(String),
+    ) -> ProjectWorkspace {
+        progress("Discovering sysroot".to_owned());
         let mut sysroot =
             Sysroot::new(project_json.sysroot.clone(), project_json.sysroot_src.clone());
-        sysroot.load_workspace(&SysrootSourceWorkspaceConfig::Stitched);
-        let query_config = QueryConfig::Rustc(&sysroot, project_json.path().as_ref());
-        let toolchain = version::get(query_config, &config.extra_env).ok().flatten();
+        let loaded_sysroot = sysroot.load_workspace(&RustSourceWorkspaceConfig::Stitched);
+        if let Some(loaded_sysroot) = loaded_sysroot {
+            sysroot.set_workspace(loaded_sysroot);
+        }
+
+        tracing::info!(workspace = %project_json.manifest_or_root(), src_root = ?sysroot.rust_lib_src_root(), root = ?sysroot.root(), "Using sysroot");
+        progress("Querying project metadata".to_owned());
+        let query_config = QueryConfig::Rustc(&sysroot, project_json.path().as_ref());
+        let targets = target_tuple::get(query_config, config.target.as_deref(), &config.extra_env)
+            .unwrap_or_default();
+
+        // We spawn a bunch of processes to query various information about the workspace's
+        // toolchain and sysroot
+        // We can speed up loading a bit by spawning all of these processes in parallel (especially
+        // on systems were process spawning is delayed)
+        let join = thread::scope(|s| {
+            let toolchain =
+                s.spawn(|| version::get(query_config, &config.extra_env).ok().flatten());
+            let rustc_cfg = s.spawn(|| {
+                rustc_cfg::get(query_config, targets.first().map(Deref::deref), &config.extra_env)
+            });
+            let data_layout = s.spawn(|| {
+                target_data_layout::get(
+                    query_config,
+                    targets.first().map(Deref::deref),
+                    &config.extra_env,
+                )
+            });
+            thread::Result::Ok((toolchain.join()?, rustc_cfg.join()?, data_layout.join()?))
+        });
+
+        let (toolchain, rustc_cfg, target_layout) = match join {
+            Ok(it) => it,
+            Err(e) => std::panic::resume_unwind(e),
+        };
 
-        let target = config.target.as_deref();
-        let rustc_cfg = rustc_cfg::get(query_config, target, &config.extra_env);
-        let data_layout = target_data_layout::get(query_config, target, &config.extra_env);
         ProjectWorkspace {
             kind: ProjectWorkspaceKind::Json(project_json),
             sysroot,
             rustc_cfg,
             toolchain,
-            target_layout: data_layout.map(Arc::from).map_err(|it| Arc::from(it.to_string())),
+            target_layout: target_layout.map(Arc::from).map_err(|it| Arc::from(it.to_string())),
             cfg_overrides: config.cfg_overrides.clone(),
             extra_includes: config.extra_includes.clone(),
         }
@@ -363,7 +458,7 @@ impl ProjectWorkspace {
     ) -> anyhow::Result<ProjectWorkspace> {
         let dir = detached_file.parent();
         let mut sysroot = match &config.sysroot {
-            Some(RustLibSource::Path(path)) => Sysroot::discover_sysroot_src_dir(path.clone()),
+            Some(RustLibSource::Path(path)) => Sysroot::discover_rust_lib_src_dir(path.clone()),
             Some(RustLibSource::Discover) => Sysroot::discover(dir, &config.extra_env),
             None => Sysroot::empty(),
         };
@@ -374,9 +469,12 @@ impl ProjectWorkspace {
             .unwrap_or_default();
         let rustc_cfg = rustc_cfg::get(query_config, None, &config.extra_env);
         let data_layout = target_data_layout::get(query_config, None, &config.extra_env);
-        sysroot.load_workspace(&SysrootSourceWorkspaceConfig::CargoMetadata(
+        let loaded_sysroot = sysroot.load_workspace(&RustSourceWorkspaceConfig::CargoMetadata(
             sysroot_metadata_config(&config.extra_env, &targets),
         ));
+        if let Some(loaded_sysroot) = loaded_sysroot {
+            sysroot.set_workspace(loaded_sysroot);
+        }
 
         let cargo_script = CargoWorkspace::fetch_metadata(
             detached_file,
@@ -545,7 +643,7 @@ impl ProjectWorkspace {
     pub fn to_roots(&self) -> Vec<PackageRoot> {
         let mk_sysroot = || {
             let mut r = match self.sysroot.workspace() {
-                SysrootWorkspace::Workspace(ws) => ws
+                RustLibSrcWorkspace::Workspace(ws) => ws
                     .packages()
                     .filter_map(|pkg| {
                         if ws[pkg].is_local {
@@ -566,12 +664,17 @@ impl ProjectWorkspace {
                         Some(PackageRoot { is_local: false, include, exclude })
                     })
                     .collect(),
-                SysrootWorkspace::Stitched(_) | SysrootWorkspace::Empty => vec![],
+                RustLibSrcWorkspace::Stitched(_) | RustLibSrcWorkspace::Empty => vec![],
             };
 
             r.push(PackageRoot {
                 is_local: false,
-                include: self.sysroot.src_root().map(|it| it.to_path_buf()).into_iter().collect(),
+                include: self
+                    .sysroot
+                    .rust_lib_src_root()
+                    .map(|it| it.to_path_buf())
+                    .into_iter()
+                    .collect(),
                 exclude: Vec::new(),
             });
             r
@@ -1385,7 +1488,7 @@ fn sysroot_to_crate_graph(
 ) -> (SysrootPublicDeps, Option<CrateId>) {
     let _p = tracing::info_span!("sysroot_to_crate_graph").entered();
     match sysroot.workspace() {
-        SysrootWorkspace::Workspace(cargo) => {
+        RustLibSrcWorkspace::Workspace(cargo) => {
             let (mut cg, mut pm) = cargo_to_crate_graph(
                 load,
                 None,
@@ -1460,7 +1563,7 @@ fn sysroot_to_crate_graph(
 
             (SysrootPublicDeps { deps: pub_deps }, libproc_macro)
         }
-        SysrootWorkspace::Stitched(stitched) => {
+        RustLibSrcWorkspace::Stitched(stitched) => {
             let cfg_options = Arc::new({
                 let mut cfg_options = CfgOptions::default();
                 cfg_options.extend(rustc_cfg);
@@ -1468,7 +1571,7 @@ fn sysroot_to_crate_graph(
                 cfg_options.insert_atom(sym::miri.clone());
                 cfg_options
             });
-            let sysroot_crates: FxHashMap<SysrootCrate, CrateId> = stitched
+            let sysroot_crates: FxHashMap<RustLibSrcCrate, CrateId> = stitched
                 .crates()
                 .filter_map(|krate| {
                     let file_id = load(&stitched[krate].root)?;
@@ -1513,7 +1616,7 @@ fn sysroot_to_crate_graph(
                 stitched.proc_macro().and_then(|it| sysroot_crates.get(&it).copied());
             (public_deps, libproc_macro)
         }
-        SysrootWorkspace::Empty => (SysrootPublicDeps { deps: vec![] }, None),
+        RustLibSrcWorkspace::Empty => (SysrootPublicDeps { deps: vec![] }, None),
     }
 }
 

crates/rust-analyzer/src/cli/rustc_tests.rs

@@ -12,8 +12,8 @@ use paths::Utf8PathBuf;
 use profile::StopWatch;
 use project_model::toolchain_info::{target_data_layout, QueryConfig};
 use project_model::{
-    CargoConfig, ManifestPath, ProjectWorkspace, ProjectWorkspaceKind, RustLibSource, Sysroot,
-    SysrootSourceWorkspaceConfig,
+    CargoConfig, ManifestPath, ProjectWorkspace, ProjectWorkspaceKind, RustLibSource,
+    RustSourceWorkspaceConfig, Sysroot,
 };
 
 use load_cargo::{load_workspace, LoadCargoConfig, ProcMacroServerChoice};
@@ -75,7 +75,11 @@ impl Tester {
         };
 
         let mut sysroot = Sysroot::discover(tmp_file.parent().unwrap(), &cargo_config.extra_env);
-        sysroot.load_workspace(&SysrootSourceWorkspaceConfig::default_cargo());
+        let loaded_sysroot = sysroot.load_workspace(&RustSourceWorkspaceConfig::default_cargo());
+        if let Some(loaded_sysroot) = loaded_sysroot {
+            sysroot.set_workspace(loaded_sysroot);
+        }
+
         let data_layout = target_data_layout::get(
             QueryConfig::Rustc(&sysroot, tmp_file.parent().unwrap().as_ref()),
             None,

crates/rust-analyzer/src/reload.rs

@@ -316,6 +316,7 @@ impl GlobalState {
                             let workspace = project_model::ProjectWorkspace::load_inline(
                                 it.clone(),
                                 &cargo_config,
+                                &progress,
                             );
                             Ok(workspace)
                         }

crates/rust-analyzer/tests/slow-tests/main.rs

@@ -1152,7 +1152,11 @@ fn resolve_proc_macro() {
         &AbsPathBuf::assert_utf8(std::env::current_dir().unwrap()),
         &Default::default(),
     );
-    sysroot.load_workspace(&project_model::SysrootSourceWorkspaceConfig::default_cargo());
+    let loaded_sysroot =
+        sysroot.load_workspace(&project_model::RustSourceWorkspaceConfig::default_cargo());
+    if let Some(loaded_sysroot) = loaded_sysroot {
+        sysroot.set_workspace(loaded_sysroot);
+    }
 
     let proc_macro_server_path = sysroot.discover_proc_macro_srv().unwrap();