lkml.org 
[lkml]   [2012]   [Jan]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH] block: add missing block_bio_complete() tracepoint
From
Hello,

On Mon, Jan 30, 2012 at 10:30 PM, Namhyung Kim <namhyung@gmail.com> wrote:
> Right, but the point is it could make a NULL pointer dereference during
> evaluation of the argument of the TP AFAICS. I'm not sure about the TP
> implementation though, I think I was wrong - T_E_C() cannot protect us from
> it because it happens just before jumping to the TP, right?
>
> So I think we need a conditional jump (with the "likely" annotation) for
> this even when the TP is disabled.

Hmmm... still not following. Where the said NULL dereference happen?
TEC conditional is equivalent to "if (COND) TP;". If you don't use
TEC, it'll be "if (COND) if (TP enabled) TP;". With TEC, it will be
"if (TP enabled) if (COND) TP;". There's no other difference.

Thanks.

--
tejun


\
 
 \ /
  Last update: 2012-01-31 11:43    [W:0.074 / U:4.116 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site