Re: [PATCH 2/2] KVM: Convert read-only users of vm_list to RCU

Jan Kiszka
2011-02-15T14:08:28Z

On 2011-02-15 13:32, Marcelo Tosatti wrote:
> On Tue, Feb 08, 2011 at 12:55:39PM +0100, Jan Kiszka wrote:
>> Only for walking the list of VMs, we do not need to hold the preemption
>> disabling kvm_lock. Convert stat services, the cpufreq callback and
>> mmu_shrink to RCU. For the latter, special care is required to
>> synchronize its list_move_tail with kvm_destroy_vm.
>>
>> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
>
> Jan,
>
> What is the motivation for this change?
>

See http://thread.gmane.org/gmane.linux.kernel/1097043

However, this proposal turned out to be incorrect. The strategy is now
to remove the stats users and reduce the lock-holding time of mmu_shrink
differently.

Jan

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