Al Viro bfd170d565 arm: optimized current_pt_regs()
... no need to read current_thread_info()->task only to
feed it to task_thread_page() immediately afterwards.
Moreover, not using current_thread_info() at all ends
up with better assembler - we need a location very close
to the top of kernel stack page and it's actually better
to do or with 0x1fff, followed be subtracting a small
constant than and with ~0x1fff, followed by adding a large
one.  Both & and | would be a couple of insns (mvn lsr/mvn lsl
for |, a pair of bic for &), but the following addition
would cost a pair of add while the subtraction ends up
as a single sub.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-30 22:21:37 -04:00
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2012-07-23 16:08:40 -07:00
2012-07-20 14:01:51 +02:00
2012-08-04 22:52:23 +08:00
2012-06-20 14:39:36 -07:00
2012-08-02 11:48:20 -07:00