Some candidates would be:
Clive Lloyd in 1974: 636 runs @ 79.50 in 5 tests, two 100s, one 50, top score of 242*
Mike Gatting in 1984: 575 runs @ 95.83 in 5 tests, two 100s, one 50, top score of 207
Alistair Cook in 2012: 562 runs @ 80.28 in 4 tests, three 100s, top score of 190
Matthew Hayden in 2001: 549 runs @ 109.80 in 3 tests, two 100s, two 50s, top score of 203
Andy Flower in 2000: 540 runs @ 270 in 2 tests, two 100s, two 50s, top score of 232*
Hashim Amla in 2010: 490 runs @ 490 in 2 tests, three 100s, top score of 253*
Younis Khan in 2005: 508 runs @ 101.60 in 3 tests, two 100s, one 50, top score of 267
Weekes and Sobers also had huge 5 test series in the 40s and 50s respectively, 779 @ 111.28 for Weekes with four 100s and 557 @ 92.83 for Sobers with three 100s. But India probably not the same force at home at that point that they are today.
Smith so far has 446 @ 89.20 with two 100s and one 50. So somewhere in that pack, tough conditions for two tests but easier runs since then. Better than average Indian attack overall I'd say, even if Ashwin hasn't been at his best.
The only series on that list I've really watched the whole way through is the one with Hayden, and I think Smith's performance this series has been better than Hayden's.