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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/s390/include/asm/preempt.h | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/s390/include/asm/preempt.h')
-rw-r--r-- | arch/s390/include/asm/preempt.h | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/arch/s390/include/asm/preempt.h b/arch/s390/include/asm/preempt.h new file mode 100644 index 000000000..bf15da0fe --- /dev/null +++ b/arch/s390/include/asm/preempt.h @@ -0,0 +1,139 @@ +/* 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); +} + +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) +{ + /* + * With some obscure config options and CONFIG_PROFILE_ALL_BRANCHES + * enabled, gcc 12 fails to handle __builtin_constant_p(). + */ + if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES)) { + if (__builtin_constant_p(val) && (val >= -128) && (val <= 127)) { + __atomic_add_const(val, &S390_lowcore.preempt_count); + return; + } + } + __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; +} + +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 */ + +#define init_task_preempt_count(p) do { } while (0) +/* Deferred to CPU bringup time */ +#define init_idle_preempt_count(p, cpu) do { } while (0) + +#ifdef CONFIG_PREEMPTION +extern void preempt_schedule(void); +#define __preempt_schedule() preempt_schedule() +extern void preempt_schedule_notrace(void); +#define __preempt_schedule_notrace() preempt_schedule_notrace() +#endif /* CONFIG_PREEMPTION */ + +#endif /* __ASM_PREEMPT_H */ |