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/* SPDX-License-Identifier: GPL-2.0-only */
#ifndef __ASM_VDSO_PROCESSOR_H
#define __ASM_VDSO_PROCESSOR_H
#ifndef __ASSEMBLY__
#include <linux/jump_label.h>
#include <asm/barrier.h>
#include <asm/hwcap.h>
static inline void cpu_relax(void)
{
if (!static_branch_likely(&riscv_isa_ext_keys[RISCV_ISA_EXT_KEY_ZIHINTPAUSE])) {
#ifdef __riscv_muldiv
int dummy;
/* In lieu of a halt instruction, induce a long-latency stall. */
__asm__ __volatile__ ("div %0, %0, zero" : "=r" (dummy));
#endif
} else {
/*
* Reduce instruction retirement.
* This assumes the PC changes.
*/
#ifdef CONFIG_TOOLCHAIN_HAS_ZIHINTPAUSE
__asm__ __volatile__ ("pause");
#else
/* Encoding of the pause instruction */
__asm__ __volatile__ (".4byte 0x100000F");
#endif
}
barrier();
}
#endif /* __ASSEMBLY__ */
#endif /* __ASM_VDSO_PROCESSOR_H */
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