From 5b776fdfe8563b8f10f238dca76391921521882d Mon Sep 17 00:00:00 2001
From: Xuan Son Nguyen <son@huggingface.co>
Date: Wed, 19 Aug 2026 12:35:18 +0200
Subject: [PATCH] refactor on_sleeping_state

---
 tools/server/server-context.cpp | 10 ++++------
 tools/server/server-queue.cpp   | 10 ++++++++--
 tools/server/server-queue.h     | 17 +++++------------
 3 files changed, 17 insertions(+), 20 deletions(-)

diff --git a/tools/server/server-context.cpp b/tools/server/server-context.cpp
index c669cf5f81..0abfff2923 100644
--- a/tools/server/server-context.cpp
+++ b/tools/server/server-context.cpp
@@ -898,6 +898,10 @@ private:
     void handle_sleeping_state(bool new_state) {
         GGML_ASSERT(sleeping != new_state);
         if (new_state) {
+            if (callback_state) {
+                callback_state(SERVER_STATE_SLEEPING, {});
+                // note: for sleeping == false, event is emitted by load_model()
+            }
             SRV_INF("%s", "server is entering sleeping state\n");
             destroy();
         } else {
@@ -4142,12 +4146,6 @@ struct server_res_generator : server_res_spipe {
 
 void server_context::set_state_callback(server_state_callback_t callback) {
     impl->callback_state = std::move(callback);
-    impl->queue_tasks.on_sleeping_state([this](bool sleeping) {
-        if (sleeping) {
-            impl->callback_state(SERVER_STATE_SLEEPING, {});
-        }
-        // for sleeping == false, event is emitted by load_model()
-    });
 }
 
 //
diff --git a/tools/server/server-queue.cpp b/tools/server/server-queue.cpp
index 2bcc9bd8f2..b679ef4a30 100644
--- a/tools/server/server-queue.cpp
+++ b/tools/server/server-queue.cpp
@@ -312,7 +312,10 @@ void server_queue::start_loop(int64_t idle_sleep_ms) {
             if (should_sleep()) {
                 QUE_INF("%s", "entering sleeping state\n");
                 sleeping = true;
-                callback_sleeping_state(true);
+                // Call order cb0 -> cb1 -> cb{N}
+                for (auto & cb : callback_sleeping_state) {
+                    cb(true);
+                }
                 req_stop_sleeping = false;
                 // wait until we are requested to exit sleeping state
                 condition_tasks.wait(lock, [&]{
@@ -323,7 +326,10 @@ void server_queue::start_loop(int64_t idle_sleep_ms) {
                 }
                 QUE_INF("%s", "exiting sleeping state\n");
                 req_stop_sleeping = false;
-                callback_sleeping_state(false);
+                // Call order cb{N} -> cb1 -> cb0
+                for (size_t i = callback_sleeping_state.size(); i > 0; i--) {
+                    callback_sleeping_state[i - 1](false);
+                }
                 sleeping = false;
                 time_last_task = ggml_time_ms();
                 condition_tasks.notify_all(); // notify wait_until_no_sleep()
diff --git a/tools/server/server-queue.h b/tools/server/server-queue.h
index 52d30095c1..4ba9ef6f6d 100644
--- a/tools/server/server-queue.h
+++ b/tools/server/server-queue.h
@@ -44,7 +44,7 @@ private:
     // callback functions
     std::function<bool(server_task &&, bool)> callback_new_task;
     std::function<void(void)>                 callback_update_slots;
-    std::function<void(bool)>                 callback_sleeping_state;
+    std::vector<std::function<void(bool)>>    callback_sleeping_state;
 
 public:
     ~server_queue() { worker_stop(); }
@@ -127,18 +127,11 @@ public:
     }
 
     // Register callback for sleeping state change; multiple callbacks are allowed
-    // note: when entering sleeping state, the callback is called AFTER sleeping is set to true
-    //       when leaving sleeping state, the callback is called BEFORE sleeping is set to false
+    // for example: register order cb0, cb1, cb2
+    // entering sleep: queue.sleeping = true --> cb0(true) --> cb1(true) --> cb2(true)
+    // leaving sleep: cb2(false) --> cb1(false) --> cb0(false) --> queue.sleeping = false
     void on_sleeping_state(std::function<void(bool)> callback) {
-        if (callback_sleeping_state) {
-            auto prev_callback = std::move(callback_sleeping_state);
-            callback_sleeping_state = [prev_callback, callback](bool sleeping) {
-                prev_callback(sleeping);
-                callback(sleeping);
-            };
-        } else {
-            callback_sleeping_state = std::move(callback);
-        }
+        callback_sleeping_state.push_back(std::move(callback));
     }
 
 private: