> 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/man4/dtrace_cam.4.md).

# dtrace\_cam.4

`dtrace_cam` — 用于跟踪 CAM 相关事件的 DTrace 提供者

## 名称

`dtrace_cam`

## 概要

`Fn cam::xpt:action union ccb *ccn Fn cam::xpt:done union ccb *ccb Fn cam::xpt:async-cb void *cbarg uint32_t async_code struct cam_path *path void *async_Arg`

## 描述

`cam` 提供者允许跟踪 CAM 事件。Fn cam::xpt\_action 探测在 CAM 控制块（ccb）提交给 CAM SIM 驱动时触发。Fn cam::xpt:done 探测在该请求完成时触发。Fn cam::xpt:async-cb 探测在异步回调被调用之前触发。

## 参见

[dtrace(1)](/man/man1/dtrace.1.md), cam(4), [SDT(9)](https://github.com/FreeBSD-Ask/freebsd-man-sc/tree/main/man9/sdt.9.md)

## 历史

`cam` 提供者首次出现于 FreeBSD 15.1 和 16.0。

## 作者

本手册页由 Warner Losh <imp@FreeBSD.org> 编写。


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