kernel/CMakeLists.txt

# SPDX-License-Identifier: Apache-2.0

# kernel is a normal CMake library and not a zephyr_library because it
# should usually not be --whole-archive'd

zephyr_syscall_header(
  ${ZEPHYR_BASE}/include/zephyr/device.h
  ${ZEPHYR_BASE}/include/zephyr/kernel.h
  ${ZEPHYR_BASE}/include/zephyr/sys/kobject.h
  ${ZEPHYR_BASE}/include/zephyr/sys/time_units.h
)

# Helper macro to append files to the kernel_files list
macro(kernel_sources_ifdef feature_toggle)
  if(${${feature_toggle}})
    list(APPEND kernel_files ${ARGN})
  endif()
endmacro()

macro(kernel_sources)
  list(APPEND kernel_files ${ARGN})
endmacro()

zephyr_syscall_header_ifdef(
  CONFIG_MMU
  ${ZEPHYR_BASE}/include/zephyr/kernel/mm.h
  ${ZEPHYR_BASE}/include/zephyr/sys/mem_manage.h
)

zephyr_syscall_header_ifdef(
  CONFIG_DEMAND_PAGING
  ${ZEPHYR_BASE}/include/zephyr/kernel/mm/demand_paging.h
)

# If a pre-built static library containing kernel code exists in
# this directory, libkernel.a, link it with the application code
# instead of building from source.
zephyr_library_get_current_dir_lib_name(${ZEPHYR_BASE} libkernel_stem)
set(libkernel ${CMAKE_CURRENT_SOURCE_DIR}/lib${libkernel_stem}${CMAKE_STATIC_LIBRARY_SUFFIX})
unset(libkernel_stem)

if(EXISTS ${libkernel})

  add_library(kernel INTERFACE)
  target_link_libraries(kernel INTERFACE ${libkernel})

else()
  # Own the kernel target in this directory so subdirectories can
  # contribute sources via target_sources().
  add_library(kernel)
  # FIXME: SHADOW_VARS: Remove this once we have enabled -Wshadow globally.
  add_compile_options($<TARGET_PROPERTY:compiler,warning_shadow_variables>)

  kernel_sources(
    main_weak.c
    busy_wait.c
    device.c
    fatal.c
    init.c
    kheap.c
    mem_slab.c
    float.c
    version.c
    )

  # Toolchain workaround: on ARM Thumb, when frame pointers are enabled,
  # both gcc and clang disallow clobbering the r7 frame pointer register
  # in inline assembly (vs. just spilling/filling as needed). Our
  # optimized arch_switch requires the ability to clobber this
  # (callee-saved) register. Turn the flag back on for the files that
  # need it. gcc enables frame pointers only at -O0; clang (pre-v20)
  # enables them at all optimization levels. (The error behavior only
  # gets modified at the level of a whole file, I tried #pragmas and
  # attributes to change the code generation for the specific functions
  # without success).
  if(CONFIG_CPU_CORTEX_M)
    if((${COMPILER} STREQUAL "gcc" AND CONFIG_NO_OPTIMIZATIONS) OR ${COMPILER} STREQUAL "clang")
      set_source_files_properties(init.c PROPERTIES COMPILE_OPTIONS -fomit-frame-pointer)
      set_source_files_properties(sched.c PROPERTIES COMPILE_OPTIONS -fomit-frame-pointer)
      set_source_files_properties(sleep.c PROPERTIES COMPILE_OPTIONS -fomit-frame-pointer)
      set_source_files_properties(thread.c PROPERTIES COMPILE_OPTIONS -fomit-frame-pointer)
    endif()
  endif()

  kernel_sources_ifdef(CONFIG_MULTITHREADING
    idle.c
    mailbox.c
    msg_q.c
    mutex.c
    queue.c
    sem.c
    stack.c
    system_work_q.c
    work.c
    condvar.c
    thread.c
    sched.c
    sleep.c
    pipe.c
    scheduler.c
    )

  if(CONFIG_MULTITHREADING)
    if(CONFIG_SCHED_SCALABLE OR CONFIG_WAITQ_SCALABLE)
      kernel_sources(priority_queues.c)
    endif()
    add_subdirectory_ifdef(CONFIG_SMP smp)
  else() # CONFIG_MULTITHREADING
    kernel_sources(nothread.c)
  endif() # CONFIG_MULTITHREADING


  kernel_sources_ifdef(CONFIG_TIMESLICING timeslicing.c)
  kernel_sources_ifdef(CONFIG_SCHED_DEADLINE deadline.c)
  kernel_sources_ifdef(CONFIG_SPIN_VALIDATE spinlock_validate.c)
  kernel_sources_ifdef(CONFIG_IRQ_OFFLOAD irq_offload.c)
  kernel_sources_ifdef(CONFIG_THREAD_MONITOR thread_monitor.c)
  kernel_sources_ifdef(CONFIG_DEMAND_PAGING_STATS paging/statistics.c)

  target_sources(kernel PRIVATE ${kernel_files})

  # Kernel files has the macro __ZEPHYR_SUPERVISOR__ set so that it
  # optimizes the code when userspace is enabled.

  set_target_properties(
    kernel
    PROPERTIES
    COMPILE_DEFINITIONS
    __ZEPHYR_SUPERVISOR__
    )

  target_sources_ifdef(CONFIG_REQUIRES_STACK_CANARIES   kernel PRIVATE compiler_stack_protect.c)
  target_sources_ifdef(CONFIG_SYS_CLOCK_EXISTS      kernel PRIVATE timeout.c timer.c)
  if(CONFIG_TIMER_READS_ITS_FREQUENCY_AT_RUNTIME OR CONFIG_SYSTEM_CLOCK_HW_CYCLES_PER_SEC_RUNTIME_UPDATE)
    target_sources(kernel PRIVATE sys_clock_hw_cycles.c)
  endif()
  target_sources_ifdef(CONFIG_MMU                   kernel PRIVATE mmu.c)
  target_sources_ifdef(CONFIG_POLL                  kernel PRIVATE poll.c)
  target_sources_ifdef(CONFIG_EVENTS                kernel PRIVATE events.c)
  target_sources_ifdef(CONFIG_SCHED_THREAD_USAGE    kernel PRIVATE usage.c)
  target_sources_ifdef(CONFIG_OBJ_CORE              kernel PRIVATE obj_core.c)

  if(${CONFIG_KERNEL_MEM_POOL})
    target_sources(kernel PRIVATE mempool.c)

    if(CONFIG_HEAP_MEM_POOL_IGNORE_MIN)
      set(final_heap_size ${CONFIG_HEAP_MEM_POOL_SIZE})
    else()
      # Import all custom HEAP_MEM_POOL size requirements
      import_kconfig(CONFIG_HEAP_MEM_POOL_ADD_SIZE_ ${DOTCONFIG} add_size_keys)

      # Calculate the sum of all "ADD_SIZE" requirements
      set(add_size_sum 0)
      foreach(add_size ${add_size_keys})
        math(EXPR add_size_sum "${add_size_sum} + ${${add_size}}")
      endforeach()

      if(CONFIG_HEAP_MEM_POOL_SIZE LESS "${add_size_sum}")
        # Only warn if default value 0 has been modified
        if(NOT CONFIG_HEAP_MEM_POOL_SIZE EQUAL 0)
          message(WARNING "
          CONFIG_HEAP_MEM_POOL_SIZE is less than requested minimum:
            ${CONFIG_HEAP_MEM_POOL_SIZE} < ${add_size_sum}
          Setting the system heap size to ${add_size_sum}")
        endif()

        set(final_heap_size ${add_size_sum})
      else()
        # CONFIG_HEAP_MEM_POOL_SIZE was greater than the sum of the requirements
        set(final_heap_size ${CONFIG_HEAP_MEM_POOL_SIZE})
      endif()

    endif()

    zephyr_linker_include_var(VAR K_HEAP_MEM_POOL_SIZE VALUE ${final_heap_size})
    zephyr_compile_definitions(K_HEAP_MEM_POOL_SIZE=${final_heap_size})
  endif()

  add_subdirectory_ifdef(CONFIG_USERSPACE userspace)
  add_subdirectory(sys)

  if(${CONFIG_DYNAMIC_THREAD})
    target_sources(kernel PRIVATE dynamic.c)
  else()
    target_sources(kernel PRIVATE dynamic_disabled.c)
  endif()

  target_include_directories(kernel PRIVATE
    ${ZEPHYR_BASE}/kernel/include
    ${ARCH_DIR}/${ARCH}/include
    )

  target_link_libraries(kernel zephyr_interface)

endif()

# Optionally build kernel sources without LTO
if(CONFIG_KERNEL_NO_LTO)
  set_target_properties(kernel PROPERTIES LTO 0)
endif()

add_dependencies(kernel zephyr_generated_headers)

unset(libkernel)