tile: avoid overflow in ns2cycles
authorHenrik Austad <henrik@austad.us>
Tue, 4 Mar 2014 08:20:53 +0000 (09:20 +0100)
committerChris Metcalf <cmetcalf@tilera.com>
Thu, 6 Mar 2014 16:53:12 +0000 (11:53 -0500)
commit767f30210bee1bb74ab042e237c2a21e77874070
tree83d5b3ea8f10688b80262172dda68e23b68816ff
parent0414855fdc4a40da05221fc6062cccbc0c30f169
tile: avoid overflow in ns2cycles

In commit 4cecf6d401a ("sched, x86: Avoid unnecessary overflow in
sched_clock") and in recent patch "clocksource: avoid unnecessary
overflow in cyclecounter_cyc2ns()" https://lkml.org/lkml/2014/3/4/17,
the mult-shift approach is replaced by 2 steps to avoid storing a large,
intermediate value that could overflow.

arch/tile/kernel/time.c has a similar pattern in cycles2ns, and this
copies the same pattern in this function

CC: John Stultz <johnstul@us.ibm.com>
CC: Mike Galbraith <bitbucket@online.de>
CC: Salman Qazi <sqazi@google.com>
Signed-off-by: Henrik Austad <henrik@austad.us>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
arch/tile/kernel/time.c