add a couple of profiling points

Cargo.lock

@@ -996,6 +996,7 @@ dependencies = [
  "ra_db 0.1.0",
  "ra_fmt 0.1.0",
  "ra_hir 0.1.0",
+ "ra_prof 0.1.0",
  "ra_syntax 0.1.0",
  "ra_text_edit 0.1.0",
  "rayon 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",

crates/ra_ide_api/Cargo.toml

@@ -23,6 +23,7 @@ ra_syntax = { path = "../ra_syntax" }
 ra_text_edit = { path = "../ra_text_edit" }
 ra_db = { path = "../ra_db" }
 ra_fmt = { path = "../ra_fmt" }
+ra_prof = { path = "../ra_prof" }
 hir = { path = "../ra_hir", package = "ra_hir" }
 test_utils = { path = "../test_utils" }
 ra_assists = { path = "../ra_assists" }

crates/ra_ide_api/src/change.rs

@@ -9,6 +9,7 @@
     salsa::{Database, SweepStrategy},
 };
 use ra_syntax::SourceFile;
+use ra_prof::profile;
 use relative_path::RelativePathBuf;
 use rayon::prelude::*;
 
@@ -153,6 +154,7 @@ pub fn prepare(
 
 impl RootDatabase {
     pub(crate) fn apply_change(&mut self, change: AnalysisChange) {
+        let _p = profile("RootDatabase::apply_change");
         log::info!("apply_change {:?}", change);
         if !change.new_roots.is_empty() {
             let mut local_roots = Vec::clone(&self.local_roots());

crates/ra_lsp_server/src/main_loop/handlers.rs

@@ -12,6 +12,7 @@
     AssistId,
 };
 use ra_syntax::{AstNode, SyntaxKind, TextUnit};
+use ra_prof::profile;
 use rustc_hash::FxHashMap;
 use serde::{Serialize, Deserialize};
 use serde_json::to_value;
@@ -328,6 +329,7 @@ pub fn handle_completion(
     world: ServerWorld,
     params: req::CompletionParams,
 ) -> Result<Option<req::CompletionResponse>> {
+    let _p = profile("handle_completion");
     let position = {
         let file_id = params.text_document.try_conv_with(&world)?;
         let line_index = world.analysis().file_line_index(file_id);
@@ -564,6 +566,7 @@ pub fn handle_code_action(
     world: ServerWorld,
     params: req::CodeActionParams,
 ) -> Result<Option<CodeActionResponse>> {
+    let _p = profile("handle_code_action");
     let file_id = params.text_document.try_conv_with(&world)?;
     let line_index = world.analysis().file_line_index(file_id);
     let range = params.range.conv_with(&line_index);