tree db0e95b8299d997fcb1264126bc8efe10d0ddd51
parent 9cfb9b3c3a7361c793c031e9c3583b177ac5debd
author Martin Schwidefsky <schwidefsky@de.ibm.com> 1230732702 +0100
committer Martin Schwidefsky <schwidefsky@de.ibm.com> 1230732709 +0100

[PATCH] fast vdso implementation for CLOCK_THREAD_CPUTIME_ID

The extract cpu time instruction (ectg) instruction allows the user
process to get the current thread cputime without calling into the
kernel. The code that uses the instruction needs to switch to the
access registers mode to get access to the per-cpu info page that
contains the two base values that are needed to calculate the current
cputime from the CPU timer with the ectg instruction.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>