lkml.org 
[lkml]   [2011]   [Sep]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [RFC][PATCH 0/5] Introduce checks for preemptable code for this_cpu_read/write()
Date
Steven Rostedt <rostedt@goodmis.org> writes:

> I just found out that the this_cpu_*() functions do not perform the
> test to see if the usage is in atomic or not. Thus, the blind
> conversion of the per_cpu(*, smp_processor_id()) and the get_cpu_var()
> code to this_cpu_*() introduce the regression to detect the hard
> to find case where a per cpu variable is used in preempt code that
> migrates and causes bugs.


Didn't preempt-rt recently get changed to not migrate in kernel-preempt
regions. How about just fixing the normal preemption to not do this
either.

Then all these complications wouldn't be necessary and a whole lot
of code related to this could be removed too, and you would still
have less bugs.

-Andi

--
ak@linux.intel.com -- Speaking for myself only


\
 
 \ /
  Last update: 2011-09-20 04:23    [from the cache]
©2003-2011 Jasper Spaans