linux_dsm_epyc7002/arch/s390/include/asm/preempt.h
Thomas Gleixner fa68645305 sched/rt, s390: Use CONFIG_PREEMPTION
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>
2019-12-08 14:37:35 +01:00

141 lines
3.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_PREEMPT_H
#define __ASM_PREEMPT_H
#include <asm/current.h>
#include <linux/thread_info.h>
#include <asm/atomic_ops.h>
#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
/* We use the MSB mostly because its available */
#define PREEMPT_NEED_RESCHED 0x80000000
#define PREEMPT_ENABLED (0 + PREEMPT_NEED_RESCHED)
static inline int preempt_count(void)
{
return READ_ONCE(S390_lowcore.preempt_count) & ~PREEMPT_NEED_RESCHED;
}
static inline void preempt_count_set(int pc)
{
int old, new;
do {
old = READ_ONCE(S390_lowcore.preempt_count);
new = (old & PREEMPT_NEED_RESCHED) |
(pc & ~PREEMPT_NEED_RESCHED);
} while (__atomic_cmpxchg(&S390_lowcore.preempt_count,
old, new) != old);
}
#define init_task_preempt_count(p) do { } while (0)
#define init_idle_preempt_count(p, cpu) do { \
S390_lowcore.preempt_count = PREEMPT_ENABLED; \
} while (0)
static inline void set_preempt_need_resched(void)
{
__atomic_and(~PREEMPT_NEED_RESCHED, &S390_lowcore.preempt_count);
}
static inline void clear_preempt_need_resched(void)
{
__atomic_or(PREEMPT_NEED_RESCHED, &S390_lowcore.preempt_count);
}
static inline bool test_preempt_need_resched(void)
{
return !(READ_ONCE(S390_lowcore.preempt_count) & PREEMPT_NEED_RESCHED);
}
static inline void __preempt_count_add(int val)
{
if (__builtin_constant_p(val) && (val >= -128) && (val <= 127))
__atomic_add_const(val, &S390_lowcore.preempt_count);
else
__atomic_add(val, &S390_lowcore.preempt_count);
}
static inline void __preempt_count_sub(int val)
{
__preempt_count_add(-val);
}
static inline bool __preempt_count_dec_and_test(void)
{
return __atomic_add(-1, &S390_lowcore.preempt_count) == 1;
}
static inline bool should_resched(int preempt_offset)
{
return unlikely(READ_ONCE(S390_lowcore.preempt_count) ==
preempt_offset);
}
#else /* CONFIG_HAVE_MARCH_Z196_FEATURES */
#define PREEMPT_ENABLED (0)
static inline int preempt_count(void)
{
return READ_ONCE(S390_lowcore.preempt_count);
}
static inline void preempt_count_set(int pc)
{
S390_lowcore.preempt_count = pc;
}
#define init_task_preempt_count(p) do { } while (0)
#define init_idle_preempt_count(p, cpu) do { \
S390_lowcore.preempt_count = PREEMPT_ENABLED; \
} while (0)
static inline void set_preempt_need_resched(void)
{
}
static inline void clear_preempt_need_resched(void)
{
}
static inline bool test_preempt_need_resched(void)
{
return false;
}
static inline void __preempt_count_add(int val)
{
S390_lowcore.preempt_count += val;
}
static inline void __preempt_count_sub(int val)
{
S390_lowcore.preempt_count -= val;
}
static inline bool __preempt_count_dec_and_test(void)
{
return !--S390_lowcore.preempt_count && tif_need_resched();
}
static inline bool should_resched(int preempt_offset)
{
return unlikely(preempt_count() == preempt_offset &&
tif_need_resched());
}
#endif /* CONFIG_HAVE_MARCH_Z196_FEATURES */
#ifdef CONFIG_PREEMPTION
extern asmlinkage void preempt_schedule(void);
#define __preempt_schedule() preempt_schedule()
extern asmlinkage void preempt_schedule_notrace(void);
#define __preempt_schedule_notrace() preempt_schedule_notrace()
#endif /* CONFIG_PREEMPTION */
#endif /* __ASM_PREEMPT_H */