race condition

- critical section
xy-241 · Jan 17, 2025 · 082985c · 082985c
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diff --git a/content/OS/Synchronization/Busy Waiting.md b/content/OS/Synchronization/Busy Waiting.md
@@ -26,4 +26,4 @@ References:
 - Also known as **自旋锁**
 - A type of [[Busy Waiting]] specifically used as a **lock mechanism** where a [[Thread]] **repeatedly checks** and attempts to **acquire a lock** until it becomes available
 - This is in contrast to [[Semaphore (信号量)]] or [[Mutex (互斥体)]], which releases the [[CPU]] and **allows other threads to run** while **waiting for the condition** to be met
-- Usually used to protect short **critical sections** in a [[Kernel]] or [[Device Controller#Device Driver]]
+- Usually used to protect short [[Race Condition (竞态条件)#Critical Section|critical sections]] in a [[Kernel]] or [[Device Controller#Device Driver]]
diff --git a/content/OS/Synchronization/Mutex (互斥体).md b/content/OS/Synchronization/Mutex (互斥体).md
@@ -13,7 +13,7 @@ References:
 ## Abstract
 ---
 - Stands for **Mutual Exclusion**
-- A [[Synchronisation (同步)]] mechanism that controls **access** to **shared resources**, such as variables, data structures, or critical sections of code, in a systems that use [[Concurrency (并发)]]
+- A [[Synchronisation (同步)]] mechanism that controls **access** to **shared resources**, such as variables, data structures, or [[Race Condition (竞态条件)#Critical Section|critical sections of code]], in a systems that use [[Concurrency (并发)]]
 - Powered by [[Atomic Instruction]]
 
 >[!success] Avoid corrupted data

diff --git a/content/OS/Synchronization/Race Condition (竞态条件).md b/content/OS/Synchronization/Race Condition (竞态条件).md
@@ -6,7 +6,7 @@ Author Profile:
 tags:
   - OS
 Creation Date: 2023-11-07T14:27:00
-Last Date: 2025-01-01T20:14:25+08:00
+Last Date: 2025-01-18T00:11:36+08:00
 References: 
 ---
 ## Abstract
@@ -15,10 +15,13 @@ References:
 
 ## Critical Section 
 ---
-- The section of codes where [[Race Condition (竞态条件)]] happens, like changing the common variables, updating a table, wiritng to a share file etc
+- A critical section is a **segment of a program’s code** where **shared resources**, such as variables, files, or devices, are accessed and modified, which may lead to [[Race Condition (竞态条件)|race conditions]]
+
 
 >[!important]
 > At any point of time, at most one [[Process (进程)]] can be in the critical section. 
+> 
+> Or **race conditions can occur in critical sections** due to the [[Concurrency (并发)|concurrent execution]] of [[Thread|threads]] that **access shared resources** without proper [[Synchronisation (同步)|synchronisation mechanisms]].
 
 
 ## References

diff --git a/content/OS/Synchronization/Synchronisation (同步).md b/content/OS/Synchronization/Synchronisation (同步).md
@@ -14,11 +14,11 @@ References:
 - **Coordination of execution** of multiple [[Process (进程)]] or [[Thread]] in a system to ensure that they **access shared resources** in a **controlled and predictable manner** 
 - The table below lists some common synchronisation methods
 
-| Synchronization Method              | Usage                                  | Advantages                       | Disadvantages                                | Example Use Case           |
-| ----------------------------------- | -------------------------------------- | -------------------------------- | -------------------------------------------- | -------------------------- |
-| [[Barrier (屏障)]]                    | Synchronise threads at **a point**     | Simple, ensures synchronisation  | Limited use cases                            | Parallel computing phases  |
-| [[Condition Variable (条件变量)]]       | Wait for condition with mutex          | Handles complex conditions       | Complex, potential [[Race Condition (竞态条件)]] | Producer-consumer problems |
-| [[Mutex (互斥体)]]                     | Protect shared data                    | Simple, effective                | Contention, potential [[Deadlock (死锁)]]      | Critical sections          |
-| [[Semaphore (信号量)]]                 | Control access to resources            | Flexible, versatile              | Complex, potential errors                    | Resource pools             |
-| [[Busy Waiting#Spinlock\|Spinlock]] | [[Busy Waiting]] for **short periods** | Low overhead for **short waits** | Inefficient for long waits                   | Low-level programming      |
+| Synchronization Method              | Usage                                  | Advantages                       | Disadvantages                                | Example Use Case                           |
+| ----------------------------------- | -------------------------------------- | -------------------------------- | -------------------------------------------- | ------------------------------------------ |
+| [[Barrier (屏障)]]                    | Synchronise threads at **a point**     | Simple, ensures synchronisation  | Limited use cases                            | Parallel computing phases                  |
+| [[Condition Variable (条件变量)]]       | Wait for condition with mutex          | Handles complex conditions       | Complex, potential [[Race Condition (竞态条件)]] | Producer-consumer problems                 |
+| [[Mutex (互斥体)]]                     | Protect shared data                    | Simple, effective                | Contention, potential [[Deadlock (死锁)]]      | [[Race Condition (竞态条件)#Critical Section]] |
+| [[Semaphore (信号量)]]                 | Control access to resources            | Flexible, versatile              | Complex, potential errors                    | Resource pools                             |
+| [[Busy Waiting#Spinlock\|Spinlock]] | [[Busy Waiting]] for **short periods** | Low overhead for **short waits** | Inefficient for long waits                   | Low-level programming                      |