Doc fixes.

[bertos.git] / kern / proc.c

diff --git a/kern/proc.c b/kern/proc.c
index f86e1ad9113c16805b66e6c90170b6d388315392..a9e956243a2677267449f74241541f87f0e55862 100644 (file)
--- a/kern/proc.c
+++ b/kern/proc.c
@@ -49,6 +49,7 @@
 #include <cpu/types.h>
 #include <cpu/attr.h>
 #include <cfg/debug.h>
+#include <cfg/module.h>
 #include <cfg/arch_config.h>  /* ARCH_EMUL */
 #include <cfg/macros.h>  /* ABS() */
 
@@ -109,6 +110,7 @@ static void proc_init_struct(Process *proc)
 #endif
 }
 
+MOD_DEFINE(proc);
 
 void proc_init(void)
 {
@@ -127,6 +129,7 @@ void proc_init(void)
 
        /* Make sure the assembly routine is up-to-date with us */
        ASSERT(asm_switch_version() == 1);
+       MOD_INIT(proc);
 }
 
 
@@ -240,12 +243,8 @@ void proc_rename(struct Process *proc, const char *name)
  */
 void proc_schedule(void)
 {
-       /* This function must not have any "auto" variables, otherwise
-        * the compiler might put them on the stack of the process
-        * being switched out.
-        */
-       static struct Process *old_process;
-       static cpuflags_t flags;
+       struct Process *old_process;
+       cpuflags_t flags;
 
        /* Remember old process to save its context later */
        old_process = CurrentProcess;
@@ -265,12 +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);
@@ -281,7 +286,7 @@ void proc_schedule(void)
         */
        if (CurrentProcess != old_process)
        {
-               static cpustack_t *dummy;
+               cpustack_t *dummy;
 
 #if CONFIG_KERN_PREEMPTIVE
                /* Reset quantum for this process */
@@ -348,8 +353,7 @@ void proc_exit(void)
  */
 void proc_switch(void)
 {
-       /* Just like proc_schedule, this function must not have auto variables. */
-       static cpuflags_t flags;
+       cpuflags_t flags;
 
        IRQ_SAVE_DISABLE(flags);
        SCHED_ENQUEUE(CurrentProcess);