[feat] Simple Multitask

Makefile

@@ -17,9 +17,11 @@ BOOT_OBJ = build/boot.o
 
 KERNEL_CPP = kernel/entry.cpp kernel/main.cpp kernel/serial.cpp kernel/fs.cpp \
              kernel/memory/heap.cpp kernel/memory/pmm.cpp \
+             kernel/scheduler/scheduler.cpp \
              graphics/context.cpp graphics/draw.cpp \
              fonts/pixel_font.cpp
-KERNEL_OBJ = $(KERNEL_CPP:%.cpp=build/%.o)
+KERNEL_ASM = kernel/scheduler/context_switch.S
+KERNEL_OBJ = $(KERNEL_CPP:%.cpp=build/%.o) $(KERNEL_ASM:%.S=build/%.o)
 
 EFI_TOP_C = $(wildcard efi/lib/*.c)
 EFI_TOP_S = $(wildcard efi/lib/*.S)
@@ -44,6 +46,7 @@ all: _bd $(EFI_OBJ) $(BOOT_OBJ) $(KERNEL_OBJ)
 
 _bd:
 	@mkdir -p build/graphics build/kernel build/fonts build/kernel/memory \
+	          build/kernel/scheduler \
 	          build/efi/lib build/efi/lib/x86_64 build/efi/lib/runtime build/efi/gnuefi
 
 $(EFI_CRT0_OBJ): efi/gnuefi/crt0-efi-x86_64.S | _bd
@@ -86,6 +89,15 @@ build/kernel/memory/%.o: kernel/memory/%.cpp | _bd
 	@echo "Compile CPP $<"
 	@g++ $(KERNEL_CXXFLAGS) -c $< -o $@
 
+build/kernel/scheduler/%.o: kernel/scheduler/%.cpp | _bd
+	@echo "Compile CPP $<"
+	@g++ $(KERNEL_CXXFLAGS) -c $< -o $@
+
+build/kernel/scheduler/%.o: kernel/scheduler/%.S | _bd
+	@echo "Compile AS $<"
+	@gcc -Iinclude -Iefi/inc -ffreestanding -fno-stack-protector -fno-stack-check \
+	    -fshort-wchar -mno-red-zone -fcf-protection=none -c $< -o $@
+
 build/graphics/%.o: graphics/%.cpp | _bd
 	@echo "Compile CPP $<"
 	@g++ $(KERNEL_CXXFLAGS) -c $< -o $@