Ingo Molnar 801c141955 sched/headers: Introduce kernel/sched/build_utility.c and build multiple .c files there
Collect all utility functionality source code files into a single kernel/sched/build_utility.c file,
via #include-ing the .c files:

    kernel/sched/clock.c
    kernel/sched/completion.c
    kernel/sched/loadavg.c
    kernel/sched/swait.c
    kernel/sched/wait_bit.c
    kernel/sched/wait.c

CONFIG_CPU_FREQ:
    kernel/sched/cpufreq.c

CONFIG_CPU_FREQ_GOV_SCHEDUTIL:
    kernel/sched/cpufreq_schedutil.c

CONFIG_CGROUP_CPUACCT:
    kernel/sched/cpuacct.c

CONFIG_SCHED_DEBUG:
    kernel/sched/debug.c

CONFIG_SCHEDSTATS:
    kernel/sched/stats.c

CONFIG_SMP:
   kernel/sched/cpupri.c
   kernel/sched/stop_task.c
   kernel/sched/topology.c

CONFIG_SCHED_CORE:
   kernel/sched/core_sched.c

CONFIG_PSI:
   kernel/sched/psi.c

CONFIG_MEMBARRIER:
   kernel/sched/membarrier.c

CONFIG_CPU_ISOLATION:
   kernel/sched/isolation.c

CONFIG_SCHED_AUTOGROUP:
   kernel/sched/autogroup.c

The goal is to amortize the 60+ KLOC header bloat from over a dozen build units into
a single build unit.

The build time of build_utility.c also roughly matches the build time of core.c and
fair.c - allowing better load-balancing of scheduler-only rebuilds.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Peter Zijlstra <peterz@infradead.org>
2022-02-23 10:58:33 +01:00

35 lines
1.4 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
# The compilers are complaining about unused variables inside an if(0) scope
# block. This is daft, shut them up.
ccflags-y += $(call cc-disable-warning, unused-but-set-variable)
# These files are disabled because they produce non-interesting flaky coverage
# that is not a function of syscall inputs. E.g. involuntary context switches.
KCOV_INSTRUMENT := n
# Disable KCSAN to avoid excessive noise and performance degradation. To avoid
# false positives ensure barriers implied by sched functions are instrumented.
KCSAN_SANITIZE := n
KCSAN_INSTRUMENT_BARRIERS := y
ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER),y)
# According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is
# needed for x86 only. Why this used to be enabled for all architectures is beyond
# me. I suspect most platforms don't need this, but until we know that for sure
# I turn this off for IA-64 only. Andreas Schwab says it's also needed on m68k
# to get a correct value for the wait-channel (WCHAN in ps). --davidm
CFLAGS_core.o := $(PROFILING) -fno-omit-frame-pointer
endif
#
# Build efficiency:
#
# These compilation units have roughly the same size and complexity - so their
# build parallelizes well and finishes roughly at once:
#
obj-y += core.o
obj-y += fair.o
obj-y += build_utility.o
obj-y += idle.o rt.o deadline.o cputime.o cpudeadline.o pelt.o