> For the complete documentation index, see [llms.txt](https://book.bsdcn.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://book.bsdcn.org/man/man9/pmap_is_prefaultable.9.md).

# pmap\_is\_prefaultable.9

`pmap_is_prefaultable` — 确定页面是否可以预故障

## 名称

`pmap_is_prefaultable`

## 概要

`#include <sys/param.h>`

`#include <vm/vm.h>`

`#include <vm/pmap.h>`

`Ft bool Fn pmap_is_prefaultable pmap_t pmap vm_offset_t va`

## 描述

`pmap_is_prefaultable` 函数提供了一种确定物理映射 `pmap` 中位于虚拟地址 `va` 处的页面是否可以预故障到主内存的方法。

这是一个由 [vm\_fault\_prefault(9)](/man/man9/vm_fault_prefault.9.md) 调用的辅助函数。

## 参见

[pmap(9)](/man/man9/pmap.9.md), [vm\_fault\_prefault(9)](/man/man9/vm_fault_prefault.9.md)

## 作者

本手册页由 Bruce M Simpson <bms@spc.org> 编写。


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