From: Sebastian Andrzej Siewior Date: Wed, 8 Mar 2023 16:29:38 +0100 Subject: [PATCH] preempt: Put preempt_enable() within an instrumentation*() section. Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/6.7/older/patches-6.7-rt6.tar.xz Callers of preempt_enable() can be within an noinstr section leading to: | vmlinux.o: warning: objtool: native_sched_clock+0x97: call to preempt_schedule_notrace_thunk() leaves .noinstr.text section | vmlinux.o: warning: objtool: kvm_clock_read+0x22: call to preempt_schedule_notrace_thunk() leaves .noinstr.text section | vmlinux.o: warning: objtool: local_clock+0xb4: call to preempt_schedule_notrace_thunk() leaves .noinstr.text section | vmlinux.o: warning: objtool: enter_from_user_mode+0xea: call to preempt_schedule_thunk() leaves .noinstr.text section | vmlinux.o: warning: objtool: syscall_enter_from_user_mode+0x140: call to preempt_schedule_thunk() leaves .noinstr.text section | vmlinux.o: warning: objtool: syscall_enter_from_user_mode_prepare+0xf2: call to preempt_schedule_thunk() leaves .noinstr.text section | vmlinux.o: warning: objtool: irqentry_enter_from_user_mode+0xea: call to preempt_schedule_thunk() leaves .noinstr.text section Signed-off-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/20230309072724.3F6zRkvw@linutronix.de --- include/linux/preempt.h | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) --- a/include/linux/preempt.h +++ b/include/linux/preempt.h @@ -230,15 +230,21 @@ do { \ #define preempt_enable() \ do { \ barrier(); \ - if (unlikely(preempt_count_dec_and_test())) \ + if (unlikely(preempt_count_dec_and_test())) { \ + instrumentation_begin(); \ __preempt_schedule(); \ + instrumentation_end(); \ + } \ } while (0) #define preempt_enable_notrace() \ do { \ barrier(); \ - if (unlikely(__preempt_count_dec_and_test())) \ + if (unlikely(__preempt_count_dec_and_test())) { \ + instrumentation_begin(); \ __preempt_schedule_notrace(); \ + instrumentation_end(); \ + } \ } while (0) #define preempt_check_resched() \