Computed @each property isn't updated

I'm using ember 2.1.0 I have 2 models - testGroup and crv.

import DS from 'ember-data';

export default DS.Model.extend({
    tag: DS.attr('string'),
    ctr: DS.attr('number', {defaultValue: 10}),
    convs: DS.attr('number', {defaultValue: 10}),
    testGroup: DS.belongsTo('testGroup')
});

And in template I show all items from testGroup.crvs with ability to change ctr/convs.

{{#each model.crvs as |crv|}}
    <tr>
        <td>{{crv.tag}}</td>
        <td>{{input value=crv.ctr}}</td>
        <td>{{input value=crv.convs}}</td>
    </tr>
{{/each}}

And at the end I want tot show total:

<div>Phases: {{total}}%</div>

For this issue I created a computed property:

total: Ember.computed('model.crvs.@each.convs', function() {
    var crvs = this.get('model').get('crvs');
    if (crvs) {
        var tmp = 0;
        crvs.forEach(function(crv) {
            tmp += parseFloat(crv.get('convs'));
        });
        return tmp;
    } else {
        return 0;
    }
}),

It shows right value when page is rendered but when I change values in crvs collection the computed property isn't changed. I can see new value in ember console.

What's wrong with my property?