Messages in this thread | | | From | Andi Kleen <> | Subject | Re: [RFC][PATCH 0/5] Introduce checks for preemptable code for this_cpu_read/write() | Date | Mon, 19 Sep 2011 19:20:17 -0700 |
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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
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