Commit 60dbc5a1 authored by Stefan Hajnoczi's avatar Stefan Hajnoczi Committed by Kevin Wolf
Browse files

vl: add qemu_add_vm_change_state_handler_prio() 



Add an API for registering vm change state handlers with a well-defined
ordering.  This is necessary when handlers depend on each other.

Small coding style fixes are included to make checkpatch.pl happy.

Signed-off-by: default avatarStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent df34fe31

include/sysemu/sysemu.h

+2 −0
Original line number Diff line number Diff line
@@ -29,6 +29,8 @@ typedef void VMChangeStateHandler(void *opaque, int running, RunState state); 


VMChangeStateEntry *qemu_add_vm_change_state_handler(VMChangeStateHandler *cb,

                                                     void *opaque);

VMChangeStateEntry *qemu_add_vm_change_state_handler_prio(

        VMChangeStateHandler *cb, void *opaque, int priority);

void qemu_del_vm_change_state_handler(VMChangeStateEntry *e);

void vm_state_notify(int running, RunState state);

vl.c

+47 −12
Original line number Diff line number Diff line
@@ -1365,27 +1365,56 @@ static int machine_help_func(QemuOpts *opts, MachineState *machine) 
struct vm_change_state_entry {

    VMChangeStateHandler *cb;

    void *opaque;

    QLIST_ENTRY (vm_change_state_entry) entries;

    QTAILQ_ENTRY(vm_change_state_entry) entries;

    int priority;

};



static QLIST_HEAD(, vm_change_state_entry) vm_change_state_head;

static QTAILQ_HEAD(, vm_change_state_entry) vm_change_state_head;



VMChangeStateEntry *qemu_add_vm_change_state_handler(VMChangeStateHandler *cb,

                                                     void *opaque)

/**

 * qemu_add_vm_change_state_handler_prio:

 * @cb: the callback to invoke

 * @opaque: user data passed to the callback

 * @priority: low priorities execute first when the vm runs and the reverse is

 *            true when the vm stops

 *

 * Register a callback function that is invoked when the vm starts or stops

 * running.

 *

 * Returns: an entry to be freed using qemu_del_vm_change_state_handler()

 */

VMChangeStateEntry *qemu_add_vm_change_state_handler_prio(

        VMChangeStateHandler *cb, void *opaque, int priority)

{

    VMChangeStateEntry *e;

    VMChangeStateEntry *other;



    e = g_malloc0(sizeof(*e));



    e->cb = cb;

    e->opaque = opaque;

    QLIST_INSERT_HEAD(&vm_change_state_head, e, entries);

    e->priority = priority;



    /* Keep list sorted in ascending priority order */

    QTAILQ_FOREACH(other, &vm_change_state_head, entries) {

        if (priority < other->priority) {

            QTAILQ_INSERT_BEFORE(other, e, entries);

            return e;

        }

    }



    QTAILQ_INSERT_TAIL(&vm_change_state_head, e, entries);

    return e;

}



VMChangeStateEntry *qemu_add_vm_change_state_handler(VMChangeStateHandler *cb,

                                                     void *opaque)

{

    return qemu_add_vm_change_state_handler_prio(cb, opaque, 0);

}



void qemu_del_vm_change_state_handler(VMChangeStateEntry *e)

{

    QLIST_REMOVE (e, entries);

    QTAILQ_REMOVE(&vm_change_state_head, e, entries);

    g_free(e);

}
@@ -1395,9 +1424,15 @@ void vm_state_notify(int running, RunState state) 


    trace_vm_state_notify(running, state, RunState_str(state));



    QLIST_FOREACH_SAFE(e, &vm_change_state_head, entries, next) {

    if (running) {

        QTAILQ_FOREACH_SAFE(e, &vm_change_state_head, entries, next) {

            e->cb(e->opaque, running, state);

        }

    } else {

        QTAILQ_FOREACH_REVERSE_SAFE(e, &vm_change_state_head, entries, next) {

            e->cb(e->opaque, running, state);

        }

    }

}



static ShutdownCause reset_requested;
@@ -2911,7 +2946,7 @@ int main(int argc, char **argv, char **envp) 
        exit(1);

    }



    QLIST_INIT (&vm_change_state_head);

    QTAILQ_INIT(&vm_change_state_head);

    os_setup_early_signal_handling();



    cpu_option = NULL;