do_async_mmap_readahead

函数名称：Asynchronous readahead happens when we find the page and PG_readahead,* so we want to possibly extend the readahead further. We return the file that* was pinned if we have to drop the mmap_sem in order to do IO.

函数原型：static struct file *do_async_mmap_readahead(struct vm_fault *vmf, struct page *page)

返回类型：struct file

参数：

类型	参数	名称
struct vm_fault *	vmf
struct page *	page

2434

file等于File we map to (can be NULL).

2435

ra等于f_ra

2436

mapping等于f_mapping

2437

struct file * fpin = NULL

2438

offset等于Logical page offset based on vma

2441

如果Flags, see mm.h. 按位与App will not benefit from clustered reads 则返回:fpin

2443

如果Cache miss stat for mmap accesses 大于0则Cache miss stat for mmap accesses 自减

2445

如果PageReadahead(page)则

2446

fpin等于maybe_unlock_mmap_for_io(vmf, fpin)

2447

page_cache_async_readahead(mapping, ra, file, page, offset, Maximum readahead window )

2450

返回:fpin

**调用者**
名称	描述
filemap_fault	lemap_fault - read in file data for page fault handling@vmf: struct vm_fault containing details of the fault filemap_fault() is invoked via the vma operations vector for a* mapped memory region to read in file data during a page fault

源代码转换工具开放的插件接口	X
支持：c/c++/esqlc/java Oracle/Informix/Mysql 插件可实现：逻辑报告代码生成和批量转换代码

函数逻辑报告