From fbd5fbd703272caa7a3afdccf7843d21e479f2b2 Mon Sep 17 00:00:00 2001
From: Antonio Scandurra <me@as-cii.com>
Date: Fri, 16 Apr 2021 16:11:55 +0200
Subject: [PATCH] Parallelize scanning of changed directories

---
 zed/src/worktree.rs | 75 +++++++++++++++++++++------------------------
 1 file changed, 35 insertions(+), 40 deletions(-)

diff --git a/zed/src/worktree.rs b/zed/src/worktree.rs
index 0b4df17f91..ba2a3e771c 100644
--- a/zed/src/worktree.rs
+++ b/zed/src/worktree.rs
@@ -434,7 +434,6 @@ impl BackgroundScanner {
             Duration::from_millis(100),
             |events| {
                 if let Err(err) = scanner.process_events(events) {
-                    dbg!(err);
                     // TODO: handle errors
                     false
                 } else {
@@ -637,6 +636,7 @@ impl BackgroundScanner {
         let mut paths = events.into_iter().map(|e| &*e.path).collect::<Vec<_>>();
         paths.sort_unstable();
 
+        let (scan_queue_tx, scan_queue_rx) = crossbeam_channel::unbounded();
         let mut paths = paths.into_iter().peekable();
         while let Some(path) = paths.next() {
             let relative_path = path.strip_prefix(&root_path)?.to_path_buf();
@@ -685,45 +685,16 @@ impl BackgroundScanner {
                         };
                         self.insert_entries(Some(dir_entry.clone()));
 
-                        let (tx, rx) = crossbeam_channel::unbounded();
-
-                        tx.send(Ok(ScanJob {
-                            ino: inode,
-                            path: Arc::from(path),
-                            relative_path,
-                            dir_entry,
-                            ignore: Some(ignore),
-                            scan_queue: tx.clone(),
-                        }))
-                        .unwrap();
-                        drop(tx);
-
-                        let mut inodes = Vec::new();
-                        inodes.resize_with(self.thread_pool.workers(), || Ok(Vec::new()));
-                        self.thread_pool.scoped(|pool| {
-                            for worker_inodes in &mut inodes {
-                                pool.execute(|| {
-                                    let worker_inodes = worker_inodes;
-                                    while let Ok(job) = rx.recv() {
-                                        if let Err(err) = job.and_then(|job| {
-                                            self.scan_dir(
-                                                job,
-                                                Some(worker_inodes.as_mut().unwrap()),
-                                            )
-                                        }) {
-                                            *worker_inodes = Err(err);
-                                            break;
-                                        }
-                                    }
-                                });
-                            }
-                        });
-
-                        for worker_inodes in inodes {
-                            for inode in worker_inodes? {
-                                removed.remove(&inode);
-                            }
-                        }
+                        scan_queue_tx
+                            .send(Ok(ScanJob {
+                                ino: inode,
+                                path: Arc::from(path),
+                                relative_path,
+                                dir_entry,
+                                ignore: Some(ignore),
+                                scan_queue: scan_queue_tx.clone(),
+                            }))
+                            .unwrap();
                     } else {
                         self.insert_entries(Some(Entry::File {
                             parent,
@@ -742,7 +713,31 @@ impl BackgroundScanner {
                 }
             }
         }
+        drop(scan_queue_tx);
 
+        let mut inodes = Vec::new();
+        inodes.resize_with(self.thread_pool.workers(), || Ok(Vec::new()));
+        self.thread_pool.scoped(|pool| {
+            for worker_inodes in &mut inodes {
+                pool.execute(|| {
+                    let worker_inodes = worker_inodes;
+                    while let Ok(job) = scan_queue_rx.recv() {
+                        if let Err(err) = job.and_then(|job| {
+                            self.scan_dir(job, Some(worker_inodes.as_mut().unwrap()))
+                        }) {
+                            *worker_inodes = Err(err);
+                            break;
+                        }
+                    }
+                });
+            }
+        });
+
+        for worker_inodes in inodes {
+            for inode in worker_inodes? {
+                removed.remove(&inode);
+            }
+        }
         self.remove_entries(removed);
 
         Ok(self.notify.receiver_count() != 0)