From f1fb4cd810f323ef05092f04906d4ca687de5645 Mon Sep 17 00:00:00 2001 From: Brendan Gregg Date: Mon, 21 Sep 2015 11:51:03 -0700 Subject: [PATCH] add dynamic tracing warning --- man/man8/biosnoop.8 | 3 +++ 1 file changed, 3 insertions(+) diff --git a/man/man8/biosnoop.8 b/man/man8/biosnoop.8 index 00f7634..2713c22 100644 --- a/man/man8/biosnoop.8 +++ b/man/man8/biosnoop.8 @@ -12,6 +12,9 @@ the I/O was first created (which usually identifies the responsible process). This uses in-kernel eBPF maps to cache process details (PID and comm) by I/O request, as well as a starting timestamp for calculating I/O latency. +This works by tracing various kernel blk_*() functions using dynamic tracing, +and will need updating to match any changes to these functions. + Since this uses BPF, only the root user can use this tool. .SH REQUIREMENTS CONFIG_BPF and bcc. -- 2.7.4