From eb9f8074c0dd9b05be0501ef1d24d85c7740c2bb Mon Sep 17 00:00:00 2001
From: Gregory Nutt <gnutt@nuttx.org>
Date: Thu, 24 Nov 2016 09:56:12 -0600
Subject: [PATCH] Update comments
---
sched/sched/sched_mergepending.c | 4 ++--
sched/sched/sched_removereadytorun.c | 16 +++++++++++-----
2 files changed, 13 insertions(+), 7 deletions(-)
diff --git a/sched/sched/sched_mergepending.c b/sched/sched/sched_mergepending.c
index 07a554ff06..863eb73c27 100644
--- a/sched/sched/sched_mergepending.c
+++ b/sched/sched/sched_mergepending.c
@@ -271,11 +271,11 @@ bool sched_mergepending(void)
return ret;
}
- cpu = sched_cpu_select(ALL_CPUS /* ptcb->affinity */);
+ cpu = sched_cpu_select(ALL_CPUS /* ptcb->affinity */);
rtcb = current_task(cpu);
}
- /* No more pending tasks can be made running. Move any reamaining
+ /* No more pending tasks can be made running. Move any remaining
* tasks in the pending task list to the ready-to-run task list.
*/
diff --git a/sched/sched/sched_removereadytorun.c b/sched/sched/sched_removereadytorun.c
index 85c3d43fac..5b6b663d97 100644
--- a/sched/sched/sched_removereadytorun.c
+++ b/sched/sched/sched_removereadytorun.c
@@ -145,7 +145,7 @@ bool sched_removereadytorun(FAR struct tcb_s *rtcb)
cpu = rtcb->cpu;
tasklist = TLIST_HEAD(rtcb->task_state, cpu);
- /* Check if the TCB to be removed is at the head of a ready to run list.
+ /* Check if the TCB to be removed is at the head of a ready-to-run list.
* For the case of SMP, there are two lists involved: (1) the
* g_readytorun list that holds non-running tasks that have not been
* assigned to a CPU, and (2) and the g_assignedtasks[] lists which hold
@@ -154,9 +154,12 @@ bool sched_removereadytorun(FAR struct tcb_s *rtcb)
* only only removing the head of that list can result in a context
* switch.
*
- * The tasklist RUNNABLE attribute will inform us if the list holds the
- * currently executing and task and, hence, if a context switch could
- * occur.
+ * rtcb->blink == NULL will tell us if the TCB is at the head of the
+ * ready-to-run list and, hence, a candidate for the new running task.
+ *
+ * If so, then the tasklist RUNNABLE attribute will inform us if the list
+ * holds the currently executing task and, hence, if a context switch
+ * should occur.
*/
if (rtcb->blink == NULL && TLIST_ISRUNNABLE(rtcb->task_state))
@@ -205,7 +208,10 @@ bool sched_removereadytorun(FAR struct tcb_s *rtcb)
rtrtcb = (FAR struct tcb_s *)rtrtcb->flink);
/* Did we find a task in the g_readytorun list? Which task should
- * we use? We decide strictly by the priority of the two tasks.
+ * we use? We decide strictly by the priority of the two tasks:
+ * Either (1) the task currently at the head of the g_assignedtasks[cpu]
+ * list (nexttcb) or (2) the highest priority task from the
+ * g_readytorun list with matching affinity (rtrtcb).
*/
if (rtrtcb != NULL && rtrtcb->sched_priority >= nxttcb->sched_priority)