Implement and enable context tracking for arm64 (which is a prerequisite for FULL_NOHZ support). This patchset builds upon earlier work by Kevin Hilman and is based on Will Deacon's tree.
Changes v5 to v6:
* Don't save far_el1 in x26 in el0_dbg path (not needed) * TIF_NOHZ processes go through the slow path (so no register save/restore is needed in ct_user_enter)
Changes v4 to v5:
* Improvement to code restoring far_el1 (suggested by Christopher Covington) * Improvement to register save/restore in ct_user_enter
Changes v3 to v4:
* Rename parameter of ct_user_exit from save to restore * Rebased patch to Will Deacon's tree (branch remotes/origin/aarch64 of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux.git)
Changes v2 to v3:
* Save/restore necessary registers in ct_user_enter and ct_user_exit * Annotate "error paths" out of el0_sync with ct_user_exit
Changes v1 to v2:
* Save far_el1 in x26 temporarily
*** BLURB HERE ***
Larry Bassel (2): arm64: adjust el0_sync so that a function can be called arm64: enable context tracking
arch/arm64/Kconfig | 1 + arch/arm64/include/asm/thread_info.h | 4 +++ arch/arm64/kernel/entry.S | 58 +++++++++++++++++++++++++++++++----- 3 files changed, 56 insertions(+), 7 deletions(-)