prevent redundant merging of the filesystems (#5066)

lib/wasix/src/bin_factory/binary_package.rs

@@ -66,6 +66,8 @@ impl BinaryPackageCommand {
 #[derivative(Debug)]
 pub struct BinaryPackage {
     pub id: PackageId,
+    /// Includes the ids of all the packages in the tree
+    pub package_ids: Vec<PackageId>,
 
     pub when_cached: Option<u128>,
     /// The name of the [`BinaryPackageCommand`] which is this package's

lib/wasix/src/runners/wasi.rs

@@ -242,6 +242,7 @@ impl WasiRunner {
         let container_fs = if let Some(pkg) = pkg {
             builder.add_webc(pkg.clone());
             builder.set_module_hash(pkg.hash());
+            builder.include_packages(pkg.package_ids.clone());
             Some(Arc::clone(&pkg.webc_fs))
         } else {
             None

lib/wasix/src/runtime/package_loader/load_package_tree.rs

@@ -42,6 +42,7 @@ pub async fn load_package_tree(
 ) -> Result<BinaryPackage, Error> {
     let mut containers = fetch_dependencies(loader, &resolution.package, &resolution.graph).await?;
     containers.insert(resolution.package.root_package.clone(), root.clone());
+    let package_ids = containers.keys().cloned().collect();
     let fs = filesystem(&containers, &resolution.package, root_is_local_dir)?;
 
     let root = &resolution.package.root_package;
@@ -52,6 +53,7 @@ pub async fn load_package_tree(
 
     let loaded = BinaryPackage {
         id: root.clone(),
+        package_ids,
         when_cached: crate::syscalls::platform_clock_time_get(
             wasmer_wasix_types::wasi::Snapshot0Clockid::Monotonic,
             1_000_000,

lib/wasix/src/state/builder.rs

@@ -1,7 +1,7 @@
 //! Builder system for configuring a [`WasiState`] and creating it.
 
 use std::{
-    collections::HashMap,
+    collections::{HashMap, HashSet},
     path::{Path, PathBuf},
     sync::Arc,
 };
@@ -10,6 +10,7 @@ use rand::Rng;
 use thiserror::Error;
 use virtual_fs::{ArcFile, FileSystem, FsError, TmpFileSystem, VirtualFile};
 use wasmer::{AsStoreMut, Extern, Imports, Instance, Module, Store};
+use wasmer_config::package::PackageId;
 
 #[cfg(feature = "journal")]
 use crate::journal::{DynJournal, SnapshotTrigger};
@@ -69,6 +70,8 @@ pub struct WasiEnvBuilder {
     /// List of webc dependencies to be injected.
     pub(super) uses: Vec<BinaryPackage>,
 
+    pub(super) included_packages: HashSet<PackageId>,
+
     pub(super) module_hash: Option<ModuleHash>,
 
     /// List of host commands to map into the WASI instance.
@@ -323,6 +326,21 @@ impl WasiEnvBuilder {
         self
     }
 
+    /// Adds a package that is already included in the [`WasiEnvBuilder`] filesystem.
+    /// These packages will not be merged to the final filesystem since they are already included.
+    pub fn include_package(&mut self, pkg_id: PackageId) -> &mut Self {
+        self.included_packages.insert(pkg_id);
+        self
+    }
+
+    /// Adds packages that is already included in the [`WasiEnvBuilder`] filesystem.
+    /// These packages will not be merged to the final filesystem since they are already included.
+    pub fn include_packages(&mut self, pkg_ids: impl IntoIterator<Item = PackageId>) -> &mut Self {
+        self.included_packages.extend(pkg_ids.into_iter());
+
+        self
+    }
+
     /// Adds a list of other containers this module inherits from.
     ///
     /// This will make all of the container's files and commands available to the
@@ -841,6 +859,10 @@ impl WasiEnvBuilder {
             wasi_fs.set_current_dir(s);
         }
 
+        for id in &self.included_packages {
+            wasi_fs.has_unioned.lock().unwrap().insert(id.clone());
+        }
+
         let state = WasiState {
             fs: wasi_fs,
             secret: rand::thread_rng().gen::<[u8; 32]>(),

lib/wasix/src/state/env.rs

@@ -1094,9 +1094,9 @@ impl WasiEnv {
         tracing::trace!(package=%pkg.id, "merging package dependency into wasi environment");
         let root_fs = &self.state.fs.root_fs;
 
-        // We first need to copy any files in the package over to the
-        // main file system
-        if let Err(e) = InlineWaker::block_on(root_fs.merge(&pkg.webc_fs)) {
+        // We first need to merge the filesystem in the package into the
+        // main file system, if it has not been merged already.
+        if let Err(e) = InlineWaker::block_on(self.state.fs.conditional_union(pkg)) {
             tracing::warn!(
                 error = &e as &dyn std::error::Error,
                 "Unable to merge the package's filesystem into the main one",