From ccdf2dc54feb5091599ceb024cc906534bfa1aad Mon Sep 17 00:00:00 2001
From: Yuke Peng <pykfirst@gmail.com>
Date: Sun, 25 Aug 2024 15:37:26 +0800
Subject: [PATCH] Drop the `MutexGuard` of semaphore earlier

---
 kernel/src/ipc/semaphore/system_v/sem.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/src/ipc/semaphore/system_v/sem.rs b/kernel/src/ipc/semaphore/system_v/sem.rs
index bc8d9ad20..b8b672c25 100644
--- a/kernel/src/ipc/semaphore/system_v/sem.rs
+++ b/kernel/src/ipc/semaphore/system_v/sem.rs
@@ -198,6 +198,7 @@ impl Semaphore {
         } else if zero_condition {
             return Ok(());
         }
+        drop(val);
 
         // Need to wait for the semaphore
         if flags.contains(IpcFlags::IPC_NOWAIT) {
@@ -219,7 +220,6 @@ impl Semaphore {
         } else {
             self.pending_alters.lock().push_back(pending_op);
         }
-        drop(val);
 
         // Wait
         if let Some(timeout) = timeout {