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D38801.id118005.diff

diff --git a/share/man/man4/dtrace_kinst.4 b/share/man/man4/dtrace_kinst.4
--- a/share/man/man4/dtrace_kinst.4
+++ b/share/man/man4/dtrace_kinst.4
@@ -24,37 +24,38 @@
.\"
.\" $FreeBSD$
.\"
-.Dd October 01, 2022
+.Dd February 27, 2023
.Dt DTRACE_KINST 4
.Os
.Sh NAME
.Nm dtrace_kinst
-.Nd a DTrace provider for tracing arbitrary instructions in a given kernel
-function.
+.Nd a DTrace provider for tracing arbitrary instructions in a given kernel function
.Sh SYNOPSIS
kinst::<function>:<instruction>
.Sh DESCRIPTION
-.Pp
The DTrace
.Nm kinst
provider allows the user to trace any instruction in a given kernel function.
<function> corresponds to the function to be traced, and <instruction> is the
offset to the specific instruction, and can be obtained from the function's
-disassembly using
-.Xr kgdb 1 .
+disassembly using kgdb from the gdb package.
.Pp
.Nm kinst
creates probes on-demand, meaning it searches for and parses the function's
instructions each time
.Xr dtrace 1
-is run, and not at module load time. This is in contrast to FBT's load-time
-parsing, since
+is run, and not at module load time.
+This is in contrast to FBT's load-time parsing, since
.Nm kinst
can potentially create thousands of probes for just a single function, instead
of up to two (entry and return) in the case of FBT.
+A result of this is that
+.Cm dtrace -l -P kinst
+will not match any probes.
+.Sh IMPLEMENTATION NOTES
+The provider is currently implemented only for amd64.
.Sh EXAMPLES
-.Pp
-Find the offset to the third instruction in
+Find the offset corresponding to the third instruction in
.Fn vm_fault
and trace it:
.Bd -literal -offset indent
@@ -66,6 +67,12 @@
0xffffffff80876df4 <+4>: 41 57 push %r15
# dtrace -n 'kinst::vm_fault:4'
+ 2 81500 vm_fault:4
+ 2 81500 vm_fault:4
+ 2 81500 vm_fault:4
+ 2 81500 vm_fault:4
+ 0 81500 vm_fault:4
+ ...
.Ed
.Pp
Trace all instructions in
@@ -73,11 +80,8 @@
.Bd -literal -offset indent
# dtrace -n 'kinst::amd64_syscall:'
.Ed
-.Sh IMPLEMENTATION NOTES
-The provider is currently implemented only for amd64.
.Sh SEE ALSO
-.Xr dtrace 1 ,
-.Xr kgdb 1
+.Xr dtrace 1
.Sh HISTORY
The
.Nm kinst

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