diff options
| author | Mark Rutland <mark.rutland@arm.com> | 2017-01-03 18:27:01 +0000 |
|---|---|---|
| committer | Amit Pundir <amit.pundir@linaro.org> | 2017-08-15 16:05:28 +0530 |
| commit | b32ed10511d469f0e05b0ada753379f4834c2169 (patch) | |
| tree | b7dbb693c4ba3370a9b76d90a855a8a31fdd9050 /mm/page_alloc.c | |
| parent | 107c1d57f89d1c758723eab704ca9cd44b86ebfe (diff) | |
UPSTREAM: arm64: restore get_current() optimisation
commit 9d84fb27fa135c99c9fe3de33628774a336a70a8 upstream.
Commit c02433dd6de32f04 ("arm64: split thread_info from task stack")
inverted the relationship between get_current() and
current_thread_info(), with sp_el0 now holding the current task_struct
rather than the current thead_info. The new implementation of
get_current() prevents the compiler from being able to optimize repeated
calls to either, resulting in a noticeable penalty in some
microbenchmarks.
This patch restores the previous optimisation by implementing
get_current() in the same way as our old current_thread_info(), using a
non-volatile asm statement.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Diffstat (limited to 'mm/page_alloc.c')
0 files changed, 0 insertions, 0 deletions