lkml.org 
[lkml]   [2021]   [Oct]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v6 1/2] ftrace: disable preemption when recursion locked
On Wed, 27 Oct 2021 10:34:13 +0800
王贇 <yun.wang@linux.alibaba.com> wrote:

> +/*
> + * Preemption will be enabled (if it was previously enabled).
> + */
> static __always_inline void trace_clear_recursion(int bit)
> {
> + WARN_ON_ONCE(bit < 0);

Can you send a v7 without the WARN_ON.

This is an extremely hot path, and this will cause noticeable overhead.

If something were to call this with bit < 0, then it would crash and
burn rather quickly.

-- Steve


> +
> + preempt_enable_notrace();
> barrier();
> trace_recursion_clear(bit);
> }

\
 
 \ /
  Last update: 2021-10-27 04:56    [W:0.038 / U:4.520 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site