On Fri, 23 Mar 2018 11:02:41 -0400 Steven Rostedt <rost...@goodmis.org> wrote:
> A while ago we had a boot tracer. But it was eventually removed: > commit 30dbb20e68e6f ("tracing: Remove boot tracer"). > > The rational was because there is already a initcall_debug boot option > that causes printk()s of all the initcall functions. "rationale" :) > The problem with the initcall_debug option is that printk() is awfully slow, > and makes it difficult to see the real impact of initcalls. Mainly because > a single printk() is usually slower than most initcall functions. Not understanding this. We do it correctly: calltime = ktime_get(); ret = fn(); rettime = ktime_get(); so the displayed initcall timing is independent of the printk() execution time?