tree bb6e80bf8f9779b33c8c54baa6c09fa049c9ec33
parent b4789b8e6be3151a955ade74872822f30e8cd914
author Hendrik Brueckner <brueckner@linux.vnet.ibm.com> 1384860369 +0100
committer Martin Schwidefsky <schwidefsky@de.ibm.com> 1384934693 +0100

s390/signal: always restore saved runtime instrumentation psw bit

Commit "s390: fix handling of runtime instrumentation psw bit" (5ebf250dab)
changed the behavior of setting the runtime instrumentation psw bit.  This
commit restores the original logic:

1. When returning from the signal handler, the runtime instrumentation psw bit
   is restored to its saved state.
2. If the runtime instrumentation psw bit is enabled during the signal handler,
   it is always turned off when leaving the signal handler.  The saved state
   is restored as described in 1.  That also implies that turning on runtime
   instrumentation in the signal handler is only effective while running in the
   signal context.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>