sched: remove csection and reduce the interrupt disabling time in sch…

…ed_[un]lock reason: 1 Accelerated the implementation of sched_lock, remove enter_critical_section in sched_lock and only enter_critical_section when task scheduling is required. 2 we add sched_lock_wo_note/sched_unlock_wo_note and it does not perform instrumentation logic Signed-off-by: hujun5 <[email protected]>
apache · Jan 22, 2025 · 977ad95 · 977ad95
1 parent 57188e6
commit 977ad95
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Showing 7 changed files with 58 additions and 302 deletions.
diff --git a/arch/xtensa/src/esp32/esp32_ble_adapter.c b/arch/xtensa/src/esp32/esp32_ble_adapter.c
@@ -2353,12 +2353,7 @@ static int32_t esp_task_create_pinned_to_core(void *entry,
   DEBUGASSERT(task_handle != NULL);
 
 #ifdef CONFIG_SMP
-  ret = sched_lock();
-  if (ret)
-    {
-      wlerr("Failed to lock scheduler before creating pinned thread\n");
-      return false;
-    }
+  sched_lock();
 #endif
 
   pid = kthread_create(name, prio, stack_depth, entry,
@@ -2390,12 +2385,7 @@ static int32_t esp_task_create_pinned_to_core(void *entry,
     }
 
 #ifdef CONFIG_SMP
-  ret = sched_unlock();
-  if (ret)
-    {
-      wlerr("Failed to unlock scheduler after creating pinned thread\n");
-      return false;
-    }
+  sched_unlock();
 #endif
 
   return pid > 0;

diff --git a/include/nuttx/sched.h b/include/nuttx/sched.h
@@ -110,6 +110,7 @@
 #define TCB_FLAG_JOIN_COMPLETED    (1 << 13)                     /* Bit 13: Pthread join completed */
 #define TCB_FLAG_FREE_TCB          (1 << 14)                     /* Bit 14: Free tcb after exit */
 #define TCB_FLAG_SIGDELIVER        (1 << 15)                     /* Bit 15: Deliver pending signals */
+#define TCB_FLAG_PREEMPT_SCHED     (1 << 16)                     /* Bit 16: tcb is PREEMPT_SCHED */
 
 /* Values for struct task_group tg_flags */
 

diff --git a/include/sched.h b/include/sched.h
@@ -265,8 +265,8 @@ int    sched_cpucount(FAR const cpu_set_t *set);
 
 /* Task Switching Interfaces (non-standard) */
 
-int    sched_lock(void);
-int    sched_unlock(void);
+void   sched_lock(void);
+void   sched_unlock(void);
 int    sched_lockcount(void);
 
 /* Queries */

diff --git a/sched/sched/sched.h b/sched/sched/sched.h
@@ -415,6 +415,8 @@ void nxsched_update_critmon(FAR struct tcb_s *tcb);
 #if CONFIG_SCHED_CRITMONITOR_MAXTIME_PREEMPTION >= 0
 void nxsched_critmon_preemption(FAR struct tcb_s *tcb, bool state,
                                 FAR void *caller);
+#else
+#  define nxsched_critmon_preemption(t, s, c)
 #endif
 
 #if CONFIG_SCHED_CRITMONITOR_MAXTIME_CSECTION >= 0

diff --git a/sched/sched/sched_lock.c b/sched/sched/sched_lock.c
@@ -64,112 +64,23 @@
  *
  ****************************************************************************/
 
-#ifdef CONFIG_SMP
-
-int sched_lock(void)
+void sched_lock(void)
 {
   FAR struct tcb_s *rtcb;
 
-  /* If the CPU supports suppression of interprocessor interrupts, then
-   * simple disabling interrupts will provide sufficient protection for
-   * the following operation.
-   */
-
-  rtcb = this_task();
-
-  /* Check for some special cases:  (1) rtcb may be NULL only during early
-   * boot-up phases, and (2) sched_lock() should have no effect if called
-   * from the interrupt level.
-   */
-
-  if (rtcb != NULL && !up_interrupt_context())
-    {
-      irqstate_t flags;
-
-      /* Catch attempts to increment the lockcount beyond the range of the
-       * integer type.
-       */
-
-      DEBUGASSERT(rtcb->lockcount < MAX_LOCK_COUNT);
-
-      flags = enter_critical_section();
-
-      /* A counter is used to support locking.  This allows nested lock
-       * operations on this thread
-       */
-
-      rtcb->lockcount++;
-
-      /* Check if we just acquired the lock */
-
-      if (rtcb->lockcount == 1)
-        {
-          /* Note that we have pre-emption locked */
-
-#if CONFIG_SCHED_CRITMONITOR_MAXTIME_PREEMPTION >= 0
-          nxsched_critmon_preemption(rtcb, true, return_address(0));
-#endif
-#ifdef CONFIG_SCHED_INSTRUMENTATION_PREEMPTION
-          sched_note_preemption(rtcb, true);
-#endif
-        }
-
-      /* Move any tasks in the ready-to-run list to the pending task list
-       * where they will not be available to run until the scheduler is
-       * unlocked and nxsched_merge_pending() is called.
-       */
-
-      nxsched_merge_prioritized(list_readytorun(),
-                                list_pendingtasks(),
-                                TSTATE_TASK_PENDING);
-
-      leave_critical_section(flags);
-    }
-
-  return OK;
-}
-
-#else /* CONFIG_SMP */
-
-int sched_lock(void)
-{
-  FAR struct tcb_s *rtcb = this_task();
-
-  /* Check for some special cases:  (1) rtcb may be NULL only during early
-   * boot-up phases, and (2) sched_lock() should have no effect if called
-   * from the interrupt level.
-   */
-
-  if (rtcb != NULL && !up_interrupt_context())
+  if (!up_interrupt_context())
     {
-      /* Catch attempts to increment the lockcount beyond the range of the
-       * integer type.
-       */
-
-      DEBUGASSERT(rtcb->lockcount < MAX_LOCK_COUNT);
-
-      /* A counter is used to support locking.  This allows nested lock
-       * operations on this thread (on any CPU)
-       */
-
-      rtcb->lockcount++;
-
-      /* Check if we just acquired the lock */
-
-      if (rtcb->lockcount == 1)
+      rtcb = this_task();
+      if (rtcb != NULL && rtcb->lockcount++ == 0)
         {
-          /* Note that we have pre-emption locked */
+#if (CONFIG_SCHED_CRITMONITOR_MAXTIME_PREEMPTION >= 0) || \
+    defined(CONFIG_SCHED_INSTRUMENTATION_PREEMPTION)
+          irqstate_t flags = enter_critical_section_wo_note();
 
-#if CONFIG_SCHED_CRITMONITOR_MAXTIME_PREEMPTION >= 0
           nxsched_critmon_preemption(rtcb, true, return_address(0));
-#endif
-#ifdef CONFIG_SCHED_INSTRUMENTATION_PREEMPTION
           sched_note_preemption(rtcb, true);
+          leave_critical_section_wo_note(flags);
 #endif
         }
     }
-
-  return OK;
 }
-
-#endif /* CONFIG_SMP */