diff options
| author | Rik van Riel <[email protected]> | 2015-02-06 15:02:02 -0500 |
|---|---|---|
| committer | Borislav Petkov <[email protected]> | 2015-02-19 11:15:53 +0100 |
| commit | 33e03dedd759cc9396252d9641b25d01909a26bb (patch) | |
| tree | ef6107500bdf187f06191588a03f8d14d2bbcdc2 | |
| parent | 1c927eea4cad83c439cb51e9c96ad19cb005157d (diff) | |
x86/fpu: Introduce task_disable_lazy_fpu_restore() helper
Currently there are a few magic assignments sprinkled through the
code that disable lazy FPU state restoring, some more effective than
others, and all equally mystifying.
It would be easier to have a helper to explicitly disable lazy
FPU state restoring for a task.
Signed-off-by: Rik van Riel <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Borislav Petkov <[email protected]>
| -rw-r--r-- | arch/x86/include/asm/fpu-internal.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/x86/include/asm/fpu-internal.h b/arch/x86/include/asm/fpu-internal.h index 217d6d7b9cb0..9c27f44e1c5c 100644 --- a/arch/x86/include/asm/fpu-internal.h +++ b/arch/x86/include/asm/fpu-internal.h @@ -79,6 +79,16 @@ static inline void __cpu_disable_lazy_restore(unsigned int cpu) per_cpu(fpu_owner_task, cpu) = NULL; } +/* + * Used to indicate that the FPU state in memory is newer than the FPU + * state in registers, and the FPU state should be reloaded next time the + * task is run. Only safe on the current task, or non-running tasks. + */ +static inline void task_disable_lazy_fpu_restore(struct task_struct *tsk) +{ + tsk->thread.fpu.last_cpu = ~0; +} + static inline int fpu_lazy_restore(struct task_struct *new, unsigned int cpu) { return new == this_cpu_read_stable(fpu_owner_task) && |