target/arm: Only flush tlb if ASID changespull-target-arm-20181019

Since QEMU does not implement ASIDs, changes to the ASID must flush the
tlb.  However, if the ASID does not change there is no reason to flush.

In testing a boot of the Ubuntu installer to the first menu, this reduces
the number of flushes by 30%, or nearly 600k instances.

Reviewed-by: Aaron Lindsay <aaron@os.amperecomputing.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20181019015617.22583-3-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

0 files changed, 0 insertions, 0 deletions