Re: [PATCH RFC] tracepoint: Introduce tracepoint callbacks executing with preempt on

From: Steven Rostedt
Date: Fri Apr 27 2018 - 12:09:12 EST


On Fri, 27 Apr 2018 11:43:41 -0400 (EDT)
Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx> wrote:

> It does so by disabling preemption in the callbacks, even when it's
> redundant with the guarantees already provided by tracepoint-sched-rcu
> and by kprobes. It's not that great for a fast-path.

Really, preempt_disable() is not bad for a fast path. It's far better
than a local_irq_disable().

-- Steve