On 20-May-2014 an earthquake swarm started in Bárðarbunga volcano or a continuum of an earthquake swarm that started on 16-May-2014 as I wrote about here. This earthquake swarm was rather small, with the largest earthquake only having the magnitude of 2,8 according to reviewed results from Icelandic Meteorological Office.
This earthquake swarm activity seems to be due to minor dike intrusion into Bárðarbunga volcano at this location. It does not mean an eruption is about to take place. More earthquake activity might take place this location in next days to weeks.