1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
<table class="head">
<tr>
<td class="head-ltitle">DTRACE_VFS(4)</td>
<td class="head-vol">Device Drivers Manual</td>
<td class="head-rtitle">DTRACE_VFS(4)</td>
</tr>
</table>
<div class="manual-text">
<section class="Sh">
<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1>
<p class="Pp"><code class="Nm">dtrace_vfs</code> — <span class="Nd">a
DTrace provider for Virtual File System</span></p>
</section>
<section class="Sh">
<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1>
<table class="Nm">
<tr>
<td><code class="Nm">vfs:<code class="Cm">fplookup</code>:<var class="Ar">function</var>:<var class="Ar">name</var></code></td>
<td></td>
</tr>
</table>
<br/>
<table class="Nm">
<tr>
<td><code class="Nm">vfs:<code class="Cm">namecache</code>:<var class="Ar">function</var>:<var class="Ar">name</var></code></td>
<td></td>
</tr>
</table>
<br/>
<table class="Nm">
<tr>
<td><code class="Nm">vfs:<code class="Cm">namei</code>:<var class="Ar">function</var>:<var class="Ar">name</var></code></td>
<td></td>
</tr>
</table>
<br/>
<table class="Nm">
<tr>
<td><code class="Nm">vfs:<code class="Cm">vop</code>:<var class="Ar">function</var>:<var class="Ar">name</var></code></td>
<td></td>
</tr>
</table>
</section>
<section class="Sh">
<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1>
<p class="Pp">The DTrace <code class="Nm">vfs</code> provider allows users to
trace events in the <a class="Xr">VFS(9)</a> layer, the kernel interface for
file systems on <span class="Ux">FreeBSD</span>.</p>
<p class="Pp">Run ‘<code class="Li">dtrace -l -P vfs</code>’ to
list all <code class="Nm">vfs</code> probes. Add <code class="Fl">-v</code>
to generate program stability reports, which contain information about the
number of probe arguments and their types.</p>
<p class="Pp" id="vfs:fplookup:lookup:done">The <code class="Cm">fplookup</code>
module defines a single probe,
<a class="permalink" href="#vfs:fplookup:lookup:done"><code class="Fn">vfs:fplookup:lookup:done</code></a>(<var class="Fa">struct
nameidata *ndp</var>, <var class="Fa">int line</var>, <var class="Fa">bool
status_code</var>), that instruments the fast path lookup code in
<a class="Xr">VFS(9)</a>.</p>
<p class="Pp">The <code class="Cm">namecache</code> module provides probes
related to the <a class="Xr">VFS(9)</a> cache. Consult the source code in
<span class="Pa">src/sys/kern/vfs_cache.c</span> for more details.</p>
<p class="Pp">The <code class="Cm">namei</code> module manages probes related to
pathname translation and lookup operations. Refer to
<a class="Xr">namei(9)</a> to learn more.</p>
<p class="Pp">The <code class="Cm">vop</code> module contains probes related to
the functions responsible for <a class="Xr">vnode(9)</a> operations.</p>
</section>
<section class="Sh">
<h1 class="Sh" id="COMPATIBILITY"><a class="permalink" href="#COMPATIBILITY">COMPATIBILITY</a></h1>
<p class="Pp">This provider is specific to <span class="Ux">FreeBSD</span>.</p>
</section>
<section class="Sh">
<h1 class="Sh" id="EXAMPLES"><a class="permalink" href="#EXAMPLES">EXAMPLES</a></h1>
<p class="Pp">Check what lookups failed to be handled in a lockless manner:</p>
<div class="Bd Pp Bd-indent Li">
<pre># dtrace -n 'vfs:fplookup:lookup:done { @[arg1, arg2] = count(); }'</pre>
</div>
</section>
<section class="Sh">
<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE
ALSO</a></h1>
<p class="Pp"><a class="Xr">dtrace(1)</a>, <a class="Xr">d(7)</a>,
<a class="Xr">SDT(9)</a>, <a class="Xr">namei(9)</a>,
<a class="Xr">VFS(9)</a></p>
<p class="Pp"><cite class="Rs"><span class="RsA">Brendan Gregg</span> and
<span class="RsA">Jim Mauro</span>, <i class="RsB">DTrace: Dynamic Tracing
in Oracle Solaris, Mac OS X and FreeBSD</i>, <i class="RsI">Prentice
Hall</i>,
<a class="RsU" href="https://www.brendangregg.com/dtracebook/">https://www.brendangregg.com/dtracebook/</a>,
<span class="RsP">pp. 335–351</span>,
<span class="RsD">2011</span>.</cite></p>
</section>
<section class="Sh">
<h1 class="Sh" id="AUTHORS"><a class="permalink" href="#AUTHORS">AUTHORS</a></h1>
<p class="Pp">The <span class="Ux">FreeBSD</span> <code class="Nm">vfs</code>
provider was written by <span class="An">Robert Watson</span>
<<a class="Mt" href="mailto:rwatson@FreeBSD.org">rwatson@FreeBSD.org</a>>.</p>
<p class="Pp">This manual page was written by <span class="An">Mateusz
Piotrowski</span>
<<a class="Mt" href="mailto:0mp@FreeBSD.org">0mp@FreeBSD.org</a>>.</p>
</section>
</div>
<table class="foot">
<tr>
<td class="foot-date">November 3, 2025</td>
<td class="foot-os">FreeBSD 15.0</td>
</tr>
</table>
|
