From acb4833aae0476d7ed2d61871036aff3eaf77c5d Mon Sep 17 00:00:00 2001
From: Chen Chengjun <chenchengjun.ccj@antgroup.com>
Date: Fri, 2 Aug 2024 11:14:14 +0800
Subject: [PATCH] Optimize trim_mappings

---
 kernel/aster-nix/src/vm/vmar/mod.rs        | 10 +++++-----
 kernel/aster-nix/src/vm/vmar/vm_mapping.rs | 12 ++++++------
 2 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/kernel/aster-nix/src/vm/vmar/mod.rs b/kernel/aster-nix/src/vm/vmar/mod.rs
index be3428937..72e66d72f 100644
--- a/kernel/aster-nix/src/vm/vmar/mod.rs
+++ b/kernel/aster-nix/src/vm/vmar/mod.rs
@@ -323,8 +323,8 @@ impl Vmar_ {
             .child_vmar_s
             .retain(|_, child_vmar_| !child_vmar_.is_destroyed());
 
-        let mut mappings_to_remove = BTreeSet::new();
-        let mut mappings_to_append = BTreeMap::new();
+        let mut mappings_to_remove = LinkedList::new();
+        let mut mappings_to_append = LinkedList::new();
 
         for vm_mapping in inner.vm_mappings.find(&range) {
             let vm_mapping_range = vm_mapping.range();
@@ -666,9 +666,9 @@ impl Vmar_ {
 
     fn trim_existing_mappings(&self, trim_range: Range<usize>) -> Result<()> {
         let mut inner = self.inner.lock();
-        let mut mappings_to_remove = BTreeSet::new();
-        let mut mappings_to_append = BTreeMap::new();
-        for vm_mapping in inner.vm_mappings.values() {
+        let mut mappings_to_remove = LinkedList::new();
+        let mut mappings_to_append = LinkedList::new();
+        for vm_mapping in inner.vm_mappings.find(&trim_range) {
             vm_mapping.trim_mapping(
                 &trim_range,
                 &mut mappings_to_remove,
diff --git a/kernel/aster-nix/src/vm/vmar/vm_mapping.rs b/kernel/aster-nix/src/vm/vmar/vm_mapping.rs
index bdec0e5b9..46e83498c 100644
--- a/kernel/aster-nix/src/vm/vmar/vm_mapping.rs
+++ b/kernel/aster-nix/src/vm/vmar/vm_mapping.rs
@@ -409,8 +409,8 @@ impl VmMapping {
     pub fn trim_mapping(
         self: &Arc<Self>,
         trim_range: &Range<usize>,
-        mappings_to_remove: &mut BTreeSet<Vaddr>,
-        mappings_to_append: &mut BTreeMap<Vaddr, Arc<VmMapping>>,
+        mappings_to_remove: &mut LinkedList<Vaddr>,
+        mappings_to_append: &mut LinkedList<(Vaddr, Arc<VmMapping>)>,
     ) -> Result<()> {
         let map_to_addr = self.map_to_addr();
         let map_size = self.map_size();
@@ -421,15 +421,15 @@ impl VmMapping {
         if trim_range.start <= map_to_addr && trim_range.end >= map_to_addr + map_size {
             // Fast path: the whole mapping was trimed.
             self.unmap(trim_range, true)?;
-            mappings_to_remove.insert(map_to_addr);
+            mappings_to_remove.push_back(map_to_addr);
             return Ok(());
         }
         if trim_range.start <= range.start {
-            mappings_to_remove.insert(map_to_addr);
+            mappings_to_remove.push_back(map_to_addr);
             if trim_range.end <= range.end {
                 // Overlap vm_mapping from left.
                 let new_map_addr = self.trim_left(trim_range.end)?;
-                mappings_to_append.insert(new_map_addr, self.clone());
+                mappings_to_append.push_back((new_map_addr, self.clone()));
             } else {
                 // The mapping was totally destroyed.
             }
@@ -438,7 +438,7 @@ impl VmMapping {
                 // The trim range was totally inside the old mapping.
                 let another_mapping = Arc::new(self.try_clone()?);
                 let another_map_to_addr = another_mapping.trim_left(trim_range.end)?;
-                mappings_to_append.insert(another_map_to_addr, another_mapping);
+                mappings_to_append.push_back((another_map_to_addr, another_mapping));
             } else {
                 // Overlap vm_mapping from right.
             }