tracing/fastboot: Document the need of initcall_debug

To use boot tracer, one should pass initcall_debug as well as
ftrace=initcall to the command line.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
LKML-Reference: <4A48735E.9050002@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Li Zefan 2009-06-29 15:55:10 +08:00 committed by Ingo Molnar
parent 82d5308127
commit 238a24f626

View File

@ -226,13 +226,13 @@ config BOOT_TRACER
the timings of the initcalls and traces key events and the identity
of tasks that can cause boot delays, such as context-switches.
Its aim is to be parsed by the /scripts/bootgraph.pl tool to
Its aim is to be parsed by the scripts/bootgraph.pl tool to
produce pretty graphics about boot inefficiencies, giving a visual
representation of the delays during initcalls - but the raw
/debug/tracing/trace text output is readable too.
You must pass in ftrace=initcall to the kernel command line
to enable this on bootup.
You must pass in initcall_debug and ftrace=initcall to the kernel
command line to enable this on bootup.
config TRACE_BRANCH_PROFILING
bool