Messages in this thread | | | Date | Wed, 18 Jul 2012 13:43:08 +0300 | From | "Michael S. Tsirkin" <> | Subject | Re: [PATCH v5 0/4] kvm: level irqfd and new eoifd |
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On Mon, Jul 16, 2012 at 02:33:38PM -0600, Alex Williamson wrote: > v5: > - irqfds now have a one-to-one mapping with eoifds to prevent users > from consuming all of kernel memory by repeatedly creating eoifds > from a single irqfd. > - implement a kvm_clear_irq() which does a test_and_clear_bit of > the irq_state, only updating the pic/ioapic if changes and allowing > the caller to know if anything was done. I added this onto the end > as it's essentially an optimization on the previous design. It's > hard to tell if there's an actual performance benefit to this.
I have to agree to this, but we need to avoid invoking kvm_set_irq in atomic context, without introducing sprurious eois.
Can bool + spinlock that previous patch has be replaced by an atomic?
> - dropped eoifd gsi support patch as it was only an FYI. > > Thanks, > > Alex > > --- > > Alex Williamson (4): > kvm: Convert eoifd to use kvm_clear_irq > kvm: Create kvm_clear_irq() > kvm: KVM_EOIFD, an eventfd for EOIs > kvm: Extend irqfd to support level interrupts > > > Documentation/virtual/kvm/api.txt | 28 +++ > arch/x86/kvm/x86.c | 3 > include/linux/kvm.h | 18 ++ > include/linux/kvm_host.h | 16 ++ > virt/kvm/eventfd.c | 333 +++++++++++++++++++++++++++++++++++++ > virt/kvm/irq_comm.c | 78 +++++++++ > virt/kvm/kvm_main.c | 11 + > 7 files changed, 483 insertions(+), 4 deletions(-)
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