Doc fixes.

[bertos.git] / kern / proc.c

diff --git a/kern/proc.c b/kern/proc.c
index f28b9819fa88e3d3251c427e2df318efa352475c..a9e956243a2677267449f74241541f87f0e55862 100644 (file)
--- a/kern/proc.c
+++ b/kern/proc.c
@@ -264,12 +264,18 @@ void proc_schedule(void)
                 * are idle-spinning, we must allow interrupts, otherwise no
                 * process will ever wake up.
                 *
+                * During idle-spinning, can occur an interrupt, it may be able to
+                * modify \p ProcReadyList. To ensure that compiler reload this
+                * variable every while cycle we call CPU_MEMORY_BARRIER.
+                * The memory barrier ensure that all variables used in this context
+                * are reloaded.
                 * \todo If there was a way to write sig_wait() so that it does not
                 * disable interrupts while waiting, there would not be any
                 * reason to do this.
                 */
                IRQ_ENABLE;
                CPU_IDLE;
+               MEMORY_BARRIER;
                IRQ_DISABLE;
        }
        IRQ_RESTORE(flags);