Files
codex/codex-rs/core/src/state/service.rs
T
Charlie Marsh 41b4fabbb4 Use latest-wins MCP manager replacement (#27259)
## Summary

We originally addressed startup prewarming holding the read side of
`RwLock<McpConnectionManager>` by snapshotting tool-list state. Review
feedback identified the broader ownership problem: the outer
synchronization should only publish or retrieve the current manager,
while MCP operations rely on the manager's internal synchronization. A
follow-up preserved operation retirement with a separate gate, but
further review questioned whether that synchronization was actually
required and whether we could support latest-wins replacement instead.

This PR now stores the current MCP manager in `ArcSwap`. Each operation
uses `load_full()` to obtain an owned `Arc<McpConnectionManager>`, then
performs MCP I/O without retaining the publication mechanism. Refresh
cancels obsolete startup work, constructs a replacement, and atomically
publishes it. New operations see the latest manager, while operations
that already loaded the previous manager retain a valid handle. Refresh
happens at a turn boundary, so there should be no active user tool calls
to drain.

Git history supports dropping the outer `RwLock`. It was introduced in
`03ffe4d595` on November 17, 2025 for non-blocking MCP startup: the
session published an empty manager, startup initialized that same object
while holding the write lock, and readers waited for initialization.
`7cd2e84026` on February 19, 2026 removed that two-phase initialization
in favor of constructing a fresh manager and swapping it in, explicitly
noting that `Option` or `OnceCell` could replace the placeholder design.
Hot reload later reused the existing lock to publish a replacement, but
I found no indication that the lock was introduced to guarantee
in-flight tool calls finish before refresh or shutdown.

Terminal shutdown remains separate from refresh: it aborts startup
prewarming and active tasks before shutting down the current manager, so
tool calls may be interrupted and no model WebSocket work continues
after shutdown. Focused regression coverage exercises pending tool-list
cancellation, deferred refresh, and startup-prewarm shutdown.
2026-06-10 08:33:21 -07:00

101 lines
4.4 KiB
Rust

use std::collections::HashMap;
use std::sync::Arc;
use crate::SkillsManager;
use crate::agent::AgentControl;
use crate::attestation::AttestationProvider;
use crate::client::ModelClient;
use crate::config::NetworkProxyAuditMetadata;
use crate::config::StartedNetworkProxy;
use crate::exec_policy::ExecPolicyManager;
use crate::guardian::GuardianRejection;
use crate::guardian::GuardianRejectionCircuitBreaker;
use crate::mcp::McpManager;
use crate::tools::code_mode::CodeModeService;
use crate::tools::network_approval::NetworkApprovalService;
use crate::tools::sandboxing::ApprovalStore;
use crate::unified_exec::UnifiedExecProcessManager;
use anyhow::Result;
use arc_swap::ArcSwap;
use arc_swap::ArcSwapOption;
use codex_analytics::AnalyticsEventsClient;
use codex_core_plugins::PluginsManager;
use codex_exec_server::EnvironmentManager;
use codex_extension_api::ExtensionData;
use codex_extension_api::ExtensionRegistry;
use codex_hooks::Hooks;
use codex_login::AuthManager;
use codex_mcp::McpConnectionManager;
use codex_models_manager::manager::SharedModelsManager;
use codex_otel::SessionTelemetry;
use codex_rollout::state_db::StateDbHandle;
use codex_rollout_trace::ThreadTraceContext;
use codex_thread_store::LiveThread;
use codex_thread_store::ThreadStore;
use std::path::PathBuf;
use tokio::runtime::Handle;
use tokio::sync::Mutex;
use tokio::sync::watch;
use tokio_util::sync::CancellationToken;
pub(crate) struct SessionServices {
/// The latest manager; callers retain an owned handle while performing MCP I/O.
pub(crate) mcp_connection_manager: ArcSwap<McpConnectionManager>,
pub(crate) mcp_startup_cancellation_token: Mutex<CancellationToken>,
pub(crate) unified_exec_manager: UnifiedExecProcessManager,
#[cfg_attr(not(unix), allow(dead_code))]
pub(crate) shell_zsh_path: Option<PathBuf>,
#[cfg_attr(not(unix), allow(dead_code))]
pub(crate) main_execve_wrapper_exe: Option<PathBuf>,
pub(crate) analytics_events_client: AnalyticsEventsClient,
pub(crate) hooks: ArcSwap<Hooks>,
pub(crate) rollout_thread_trace: ThreadTraceContext,
pub(crate) user_shell: Arc<crate::shell::Shell>,
pub(crate) shell_snapshot_tx: watch::Sender<Option<Arc<crate::shell_snapshot::ShellSnapshot>>>,
pub(crate) show_raw_agent_reasoning: bool,
pub(crate) exec_policy: Arc<ExecPolicyManager>,
pub(crate) auth_manager: Arc<AuthManager>,
pub(crate) models_manager: SharedModelsManager,
pub(crate) session_telemetry: SessionTelemetry,
pub(crate) tool_approvals: Mutex<ApprovalStore>,
pub(crate) guardian_rejections: Mutex<HashMap<String, GuardianRejection>>,
pub(crate) guardian_rejection_circuit_breaker: Mutex<GuardianRejectionCircuitBreaker>,
pub(crate) runtime_handle: Handle,
pub(crate) skills_manager: Arc<SkillsManager>,
pub(crate) plugins_manager: Arc<PluginsManager>,
pub(crate) mcp_manager: Arc<McpManager>,
pub(crate) extensions: Arc<ExtensionRegistry<crate::config::Config>>,
pub(crate) session_extension_data: ExtensionData,
pub(crate) thread_extension_data: ExtensionData,
pub(crate) agent_control: AgentControl,
pub(crate) network_proxy: ArcSwapOption<StartedNetworkProxy>,
pub(crate) network_proxy_audit_metadata: NetworkProxyAuditMetadata,
pub(crate) managed_network_requirements_configured: bool,
pub(crate) network_approval: Arc<NetworkApprovalService>,
pub(crate) state_db: Option<StateDbHandle>,
pub(crate) live_thread: Option<LiveThread>,
pub(crate) thread_store: Arc<dyn ThreadStore>,
pub(crate) attestation_provider: Option<Arc<dyn AttestationProvider>>,
/// Session-scoped model client shared across turns.
pub(crate) model_client: ModelClient,
pub(crate) code_mode_service: CodeModeService,
/// Shared process-level environment registry. Sessions carry an `Arc` handle so they can pass
/// the same manager through child-thread spawn paths without reconstructing it.
pub(crate) environment_manager: Arc<EnvironmentManager>,
}
impl SessionServices {
/// Installs the manager before validating required servers so startup-time elicitation can
/// resolve through the session's manager while validation waits.
pub(crate) async fn install_mcp_connection_manager(
&self,
manager: McpConnectionManager,
) -> Result<()> {
self.mcp_connection_manager.store(Arc::new(manager));
self.mcp_connection_manager
.load_full()
.validate_required_servers()
.await
}
}