[docs][utest]:Add comments for smp_bind_affinity

Add comments for smp_bind_affinity, And fixed some comment issues in smp_affinity_pri2_tc.

Signed-off-by: Mengchen Teng <teng_mengchen@163.com>

Author: Tm-C-mT

src/utest/smp/smp_affinity_pri2_tc.c

@@ -22,11 +22,11 @@
  * Test Case Name: [smp_affinity_pri2]
  *
  * Test Objectives:
- * - Verify that threads with low-priority unbound cores do not preempt high-priority threads.
+ * - Verify that a low-priority thread bound to a core does not preempt a higher-priority thread running on the same core.
  *
  * Test Scenarios:
- * - RT_CPUS_NR threads (T0~T(RT_CPUS_NR-1)) are created, with each thread bound to its respective core. Among them,
- * - the thread on core 0 has a medium priority (THIGH_PRIORITY), while the other threads have the highest priority (THREAD_PRIORITY).
+ * - RT_CPUS_NR threads (T0~T(RT_CPUS_NR-1)) are created. T0 is unbound with medium priority (THIGH_PRIORITY), while
+ * - threads T1~T(RT_CPUS_NR-1) are each bound to their respective cores with the highest priority (THREAD_PRIORITY).
  * - All threads share a common entry function thread_entry. In thread_entry, only the threads running on non-core-0 cores
  * - execute an infinite loop (i.e., they do not release core ownership). After running for a certain period of time,
  * - the thread on core 0 checks whether run_flag equals 0 after creating a low-priority (LOW_PRIORITY) thread Tn. The entry

src/utest/smp/smp_bind_affinity_tc.c

@@ -17,6 +17,29 @@
  * @note    Create RT_CPUS_NR threads, thread 0 is bound to core 0, other threads are not bound to specific cores,
  *          after running for a set number of times, count the number of times each core is run on the corresponding core,
  *          thread 0 should always be run on core 0, other threads will be run on different cores.
+ *
+ * Test Case Name: [smp_bind_affinity]
+ *
+ * Test Objectives:
+ * - Verify that threads bound to specific cores run on those cores.
+ *
+ * Test Scenarios:
+ * - RT_CPUS_NR threads (T0~T(RT_CPUS_NR-1)) are created, with only T0 bound to core 0. When thread Tx is running,
+ * - thread_tic[x] increments by 1; if x is equal to the core ID, thread_inc[x] also increments by 1. After the
+ * - program runs for a period of time, observe the value relationship between the thread_inc and thread_tic arrays.
+ * - If thread_inc[x] is equal to thread_tic[x], it indicates that thread Tx is correctly bound to core x. In this test case,
+ * - only thread_inc[0] will be equal to thread_tic[0].
+ *
+ * Verification Metrics:
+ * - Output message: [I/utest] [ PASSED ] [ result ] testcase (core.smp_bind_affinity)
+ *
+ * Dependencies:
+ * - Enable RT_USING_SMP, set RT_THREAD_PRIORITY_MAX = 256.
+ *
+ * Expected Results:
+ * - You will see the relevant PASS message. Additionally, RT_CPUS_NR lines of printed information will be displayed,
+ * - indicating whether each thread Tx has been running on core x all the time. The results show that only T0 has been
+ * - running on core 0 consistently.
  */
 
 /* Number of thread runs */