Makefile: Add SCHED flags to switch scheduler

Author: mlouielu

Makefile

@@ -39,7 +39,7 @@ deps := $(OBJS:%.o=.%.o.d)
 
 .PHONY: all check clean distclean
 
-all: $(CMSIS)/$(TARGET) $(NAME).lds $(NAME).bin
+all: $(CMSIS)/$(TARGET) $(NAME).lds $(NAME).bin SCHED_FLAGS
 
 # generic build rules
 include mk/flags.mk

README.md

@@ -15,3 +15,17 @@ $ python -m tests
 # Run partial test with command line tools
 $ python -m tests fs_1 cond_2
 ```
+
+## Makefile
+
+You can switch scheduler by makefile flags:
+
+```
+# Using bitmap scheduler
+
+$ make SCHED=BITMAP
+
+# Using RR scheduler
+
+$ make SCHED=RR
+```

kernel/main.c

@@ -45,6 +45,11 @@ void init_IRQ(void);
 struct task_info idle_task;
 struct task_info main_task;
 
+/* Select scheduler */
+#ifndef SCHED_CLASS
+#define SCHED_CLASS SCHED_CLASS_BITMAP
+#endif
+
 void print_version(void)
 {
     char buf[] = {0, 0};
@@ -131,7 +136,7 @@ struct thread_info *start_kernel(void)
     kmem_cache_init();
 
     /* select a scheduling policy */
-    sched_select(SCHED_CLASS_BITMAP);
+    sched_select(SCHED_CLASS);
 
     /* idle_thread is not added to the runqueue */
     task_init(&idle_task);

mk/flags.mk

@@ -24,6 +24,13 @@ CFLAGS += \
 CFLAGS += \
     -D CONFIG_KERNEL_STACK_CHECKING
 
+# Scheduler
+ifdef SCHED
+    CFLAGS += -D SCHED_CLASS=SCHED_CLASS_$(SCHED)
+SCHED_FLAGS:
+	$(Q)$(RM) kernel/main.o
+endif
+
 LDFLAGS += \
     -nostartfiles -specs=nano.specs \
     -Wl,-Map=$(NAME).map -Wl,-Tpiko.lds -Wl,--gc-sections