blob: edc08f04aef7745045f9d76fc4491adb851fa759 [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef _ASM_POWERPC_PARAVIRT_H
#define _ASM_POWERPC_PARAVIRT_H
#include <linux/jump_label.h>
#include <asm/smp.h>
#ifdef CONFIG_PPC64
#include <asm/paca.h>
#include <asm/hvcall.h>
#endif
#ifdef CONFIG_PPC_SPLPAR
#include <asm/kvm_guest.h>
#include <asm/cputhreads.h>
DECLARE_STATIC_KEY_FALSE(shared_processor);
static inline bool is_shared_processor(void)
{
return static_branch_unlikely(&shared_processor);
}
/* If bit 0 is set, the cpu has been preempted */
static inline u32 yield_count_of(int cpu)
{
__be32 yield_count = READ_ONCE(lppaca_of(cpu).yield_count);
return be32_to_cpu(yield_count);
}
static inline void yield_to_preempted(int cpu, u32 yield_count)
{
plpar_hcall_norets(H_CONFER, get_hard_smp_processor_id(cpu), yield_count);
}
static inline void prod_cpu(int cpu)
{
plpar_hcall_norets(H_PROD, get_hard_smp_processor_id(cpu));
}
static inline void yield_to_any(void)
{
plpar_hcall_norets(H_CONFER, -1, 0);
}
#else
static inline bool is_shared_processor(void)
{
return false;
}
static inline u32 yield_count_of(int cpu)
{
return 0;
}
extern void ___bad_yield_to_preempted(void);
static inline void yield_to_preempted(int cpu, u32 yield_count)
{
___bad_yield_to_preempted(); /* This would be a bug */
}
extern void ___bad_yield_to_any(void);
static inline void yield_to_any(void)
{
___bad_yield_to_any(); /* This would be a bug */
}
extern void ___bad_prod_cpu(void);
static inline void prod_cpu(int cpu)
{
___bad_prod_cpu(); /* This would be a bug */
}
#endif
#define vcpu_is_preempted vcpu_is_preempted
static inline bool vcpu_is_preempted(int cpu)
{
if (!is_shared_processor())
return false;
#ifdef CONFIG_PPC_SPLPAR
if (!is_kvm_guest()) {
int first_cpu = cpu_first_thread_sibling(smp_processor_id());
/*
* Preemption can only happen at core granularity. This CPU
* is not preempted if one of the CPU of this core is not
* preempted.
*/
if (cpu_first_thread_sibling(cpu) == first_cpu)
return false;
}
#endif
if (yield_count_of(cpu) & 1)
return true;
return false;
}
static inline bool pv_is_native_spin_unlock(void)
{
return !is_shared_processor();
}
#endif /* _ASM_POWERPC_PARAVIRT_H */