KVM: Don't keep reference to irq routing table in irqfd struct
This makes the irqfd code keep a copy of the irq routing table entry
for each irqfd, rather than a reference to the copy in the actual
irq routing table maintained in kvm/virt/irqchip.c. This will enable
us to change the routing table structure in future, or even not have a
routing table at all on some platforms.
The synchronization that was previously achieved using srcu_dereference
on the read side is now achieved using a seqcount_t structure. That
ensures that we don't get a halfway-updated copy of the structure if
we read it while another thread is updating it.
We still use srcu_read_lock/unlock around the read side so that when
changing the routing table we can be sure that after calling
synchronize_srcu, nothing will be using the old routing.
Signed-off-by: Paul Mackerras <[email protected]>
Tested-by: Eric Auger <[email protected]>
Tested-by: Cornelia Huck <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
1 file changed
