Share your experience!
how to Root Xperia u..??
it depends on the firmware version you are using
if b.10- search root many android in google
b.54 or above see the following link
http://forum.xda-developers.com/showpost.php?p=35339192&postcount=173
gb- f;ash a kernel
If you got time then please visit here:::::::::::::::::
TOP APPS for XPU::::
http://talk.sonymobile.com/thread/58158?tstart=0
Latest firmware ICS here and the guide to install it
http://forum.xda-developers.com/showpost.php?p=35339192&postcount=173
Custom Roms::
http://talk.sonymobile.com/thread/56689?tstart=0
If you are rooted then please visit
http://talk.sonymobile.com/thread/56641?tstart=0
http://talk.sonymobile.com/thread/56642?tstart=0
If you want to root:
http://forum.xda-developers.com/showthread.php?t=1886460
Please Mark
I rooted my Xperia U by following the steps from http://playfuldroid.com/tutorial-how-to-root-sony-xperia-u/ . Quite an easy process compared to other manufacturers.
already tried these but no go 
Please refer this link. I got it done finally.