Commit 80b7d2ef authored by Jan Kiszka's avatar Jan Kiszka Committed by Paolo Bonzini
Browse files

kvm: Switch to unlocked PIO 



Do not take the BQL before dispatching PIO requests of KVM VCPUs.
Instead, address_space_rw will do it if necessary. This enables
completely BQL-free PIO handling in KVM mode for upcoming devices with
fine-grained locking.

Signed-off-by: default avatarJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Message-Id: <1434646046-27150-8-git-send-email-pbonzini@redhat.com>
parent 4b8523ee

kvm-all.c

+1 −2
Original line number Diff line number Diff line
@@ -1804,13 +1804,12 @@ int kvm_cpu_exec(CPUState *cpu) 
        switch (run->exit_reason) {

        case KVM_EXIT_IO:

            DPRINTF("handle_io\n");

            qemu_mutex_lock_iothread();

            /* Called outside BQL */

            kvm_handle_io(run->io.port, attrs,

                          (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: