[PATCH v8 0/2] context tracker support for arm64

Larry Bassel larry.bassel at linaro.org
Tue Jun 3 14:29:49 PDT 2014

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 v7 to v8:

* Fix bug where el1_irq was calling ct_user_exit rather than el0_irq

Changes v6 to v7:

* Rename parameter of ct_user_exit from restore to syscall

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

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(-)


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