tree 88062deeeb7f8d6973056422f08d47f8c5a27c51
parent f75664570d8b75469cc468f23c2b27220984983b
author Jens Axboe <jaxboe@fusionio.com> 1302596908 +0200
committer Jens Axboe <jaxboe@fusionio.com> 1302596908 +0200

block: readd plug trace event

This was removed with the queue plug state. But we can easily readd
by checking if this is the first request going to this queue. It's
good information to have when tracing to see how effective the
plugging is.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>