Leinster cruised into the Heineken Champions Cup round of 16 after sweeping aside Gloucester at Kingsholm.The four-time European champions were never seriously threatened as they followed up a 57-0 victory over the same opponents before Christmas with another comprehensive success.Leo Cullen's side secured a bonus-point by half-time through tries from wing Jordan Larmour, prop Michael Ala'alatoa, centre Jamie Osborne and number eight Caelan Doris.Fly-half Ross Byrne converted all four scores and, although Gloucester claimed two penalty tries from collapsed mauls, it was damage limitation from an early stage.Leinster full-back Hugo Keenan crossed early in the second period for a try that Byrne again converted, then flanker Josh van der Flier touched down, with replacement Harry Byrne adding the extras.And Ronan Kelleher added a seventh Leinster try on the stroke of full-time, converted by Harry Byrne, leaving Gloucester to reflect on their heaviest home defeat in top-flight European competition.With eight teams qualifying from each of two pools, though, Gloucester could still reach the Champions Cup knockout phase if they beat Bordeaux-Begles in France next weekend.But for Leinster, it is already a case of mission accomplished in terms of progressing from their group, and a record-equalling fifth European title is certainly not beyond them on current form.Gloucester showed two changes from the team edged out by Gallagher Premiership opponents Saracens, with George Barton replacing full-back Lloyd Evans and Seb Atkinson starting at inside centre instead of Giorgi Kveseladze.Centre Garry Ringrose returned to captain Leinster, while prop Cian Healy was set to make his 100th appearance for the province after being named among