Messages in this thread |  | | | Subject | Re: [PATCH 3/5] writeback: fix dirtied pages accounting on sub-page writes | | From | Peter Zijlstra <> | | Date | Tue, 22 Nov 2011 13:57:42 +0100 |
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On Tue, 2011-11-22 at 13:21 +0100, Jan Kara wrote: > > + __get_cpu_var(bdp_ratelimits)++; > I think you need preempt_disable() and preempt_enable() pair around > __get_cpu_var(). Otherwise a process could get rescheduled in the middle of > read-modify-write cycle...
there's of course the this_cpu_inc(bdp_ratelimits); thing.
On x86 that'll turn into a single insn, on others it will add the required preempt_disable/enable bits.
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