sentences:  The 30th Canto, 160, in translation, reads -
  The monarch of the world circumambulated the shrine thrice and stood there proferring his respects.In front of him the Arya kings released from prison, kings removed from central jail, the Kongu ruler of Kudagu, the king of Malva and "Kayavaku, the king of sea-girt Ceylon, prayed reverently to the deity thus..."
  "Kayavaku" here, despite some disagreement has been conjectured to mean "Gajabahu".The "Silappatikaram", therefore is read to imply that, "Gajabahu" was a contemporary of the Chera king Senguttuvan, the protagonist of the epic.