From: Jan Kiszka <jan.kis...@siemens.com>
Do not take the BQL before dispatching PIO requests of KVM VCPUs.
Instead, call the unlocked version of address_space_rw. This enables
completely BQL-free PIO handling in KVM mode for upcoming devices with
fine-grained locking.
Signed-off-by: Jan Kiszka <jan.kis...@siemens.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
kvm-all.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/kvm-all.c b/kvm-all.c
index 8da1deb..2848e5b 100644
--- a/kvm-all.c
+++ b/kvm-all.c
@@ -1647,8 +1647,8 @@ static void kvm_handle_io(uint16_t port, void *data, int
direction, int size,
uint8_t *ptr = data;
for (i = 0; i < count; i++) {
- address_space_rw(&address_space_io, port, ptr, size,
- direction == KVM_EXIT_IO_OUT);
+ address_space_rw_unlocked(&address_space_io, port, ptr, size,
+ direction == KVM_EXIT_IO_OUT);
ptr += size;
}
}
@@ -1804,13 +1804,11 @@ int kvm_cpu_exec(CPUState *cpu)
switch (run->exit_reason) {
case KVM_EXIT_IO:
DPRINTF("handle_io\n");
- qemu_mutex_lock_iothread();
kvm_handle_io(run->io.port,
(uint8_t *)run + run->io.data_offset,
run->io.direction,
run->io.size,
run->io.count);
- qemu_mutex_unlock_iothread();
ret = 0;
break;
case KVM_EXIT_MMIO:
--
2.3.0
