fa68645305
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same functionality which today depends on CONFIG_PREEMPT. Switch the preemption and entry code over to use CONFIG_PREEMPTION. Add PREEMPT_RT output to die(). [bigeasy: +Kconfig, dumpstack.c] Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: linux-s390@vger.kernel.org Link: https://lore.kernel.org/r/20191015191821.11479-18-bigeasy@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
141 lines
3.1 KiB
C
141 lines
3.1 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef __ASM_PREEMPT_H
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#define __ASM_PREEMPT_H
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#include <asm/current.h>
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#include <linux/thread_info.h>
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#include <asm/atomic_ops.h>
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#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
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/* We use the MSB mostly because its available */
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#define PREEMPT_NEED_RESCHED 0x80000000
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#define PREEMPT_ENABLED (0 + PREEMPT_NEED_RESCHED)
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static inline int preempt_count(void)
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{
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return READ_ONCE(S390_lowcore.preempt_count) & ~PREEMPT_NEED_RESCHED;
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}
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static inline void preempt_count_set(int pc)
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{
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int old, new;
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do {
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old = READ_ONCE(S390_lowcore.preempt_count);
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new = (old & PREEMPT_NEED_RESCHED) |
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(pc & ~PREEMPT_NEED_RESCHED);
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} while (__atomic_cmpxchg(&S390_lowcore.preempt_count,
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old, new) != old);
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}
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#define init_task_preempt_count(p) do { } while (0)
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#define init_idle_preempt_count(p, cpu) do { \
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S390_lowcore.preempt_count = PREEMPT_ENABLED; \
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} while (0)
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static inline void set_preempt_need_resched(void)
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{
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__atomic_and(~PREEMPT_NEED_RESCHED, &S390_lowcore.preempt_count);
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}
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static inline void clear_preempt_need_resched(void)
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{
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__atomic_or(PREEMPT_NEED_RESCHED, &S390_lowcore.preempt_count);
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}
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static inline bool test_preempt_need_resched(void)
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{
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return !(READ_ONCE(S390_lowcore.preempt_count) & PREEMPT_NEED_RESCHED);
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}
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static inline void __preempt_count_add(int val)
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{
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if (__builtin_constant_p(val) && (val >= -128) && (val <= 127))
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__atomic_add_const(val, &S390_lowcore.preempt_count);
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else
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__atomic_add(val, &S390_lowcore.preempt_count);
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}
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static inline void __preempt_count_sub(int val)
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{
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__preempt_count_add(-val);
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}
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static inline bool __preempt_count_dec_and_test(void)
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{
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return __atomic_add(-1, &S390_lowcore.preempt_count) == 1;
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}
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static inline bool should_resched(int preempt_offset)
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{
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return unlikely(READ_ONCE(S390_lowcore.preempt_count) ==
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preempt_offset);
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}
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#else /* CONFIG_HAVE_MARCH_Z196_FEATURES */
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#define PREEMPT_ENABLED (0)
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static inline int preempt_count(void)
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{
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return READ_ONCE(S390_lowcore.preempt_count);
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}
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static inline void preempt_count_set(int pc)
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{
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S390_lowcore.preempt_count = pc;
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}
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#define init_task_preempt_count(p) do { } while (0)
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#define init_idle_preempt_count(p, cpu) do { \
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S390_lowcore.preempt_count = PREEMPT_ENABLED; \
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} while (0)
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static inline void set_preempt_need_resched(void)
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{
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}
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static inline void clear_preempt_need_resched(void)
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{
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}
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static inline bool test_preempt_need_resched(void)
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{
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return false;
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}
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static inline void __preempt_count_add(int val)
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{
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S390_lowcore.preempt_count += val;
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}
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static inline void __preempt_count_sub(int val)
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{
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S390_lowcore.preempt_count -= val;
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}
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static inline bool __preempt_count_dec_and_test(void)
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{
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return !--S390_lowcore.preempt_count && tif_need_resched();
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}
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static inline bool should_resched(int preempt_offset)
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{
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return unlikely(preempt_count() == preempt_offset &&
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tif_need_resched());
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}
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#endif /* CONFIG_HAVE_MARCH_Z196_FEATURES */
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#ifdef CONFIG_PREEMPTION
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extern asmlinkage void preempt_schedule(void);
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#define __preempt_schedule() preempt_schedule()
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extern asmlinkage void preempt_schedule_notrace(void);
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#define __preempt_schedule_notrace() preempt_schedule_notrace()
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#endif /* CONFIG_PREEMPTION */
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#endif /* __ASM_PREEMPT_H */
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