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x86/fpu: Use an explicit if/else in switch_fpu_prepare()

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Use an explicit if/else branch after __save_init_fpu(old) in
switch_fpu_prepare(). This makes substituting the assignment with a call
in task_disable_lazy_fpu_restore() in the next patch easier to review.

Signed-off-by: Rik van Riel <riel@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Link: http://lkml.kernel.org/r/1423252925-14451-7-git-send-email-riel@redhat.com
[ Space out stuff for more readability. ]
Signed-off-by: Borislav Petkov <bp@suse.de>
This commit is contained in:
Rik van Riel 2015-02-06 15:02:03 -05:00 committed by Borislav Petkov
parent 33e03dedd7
commit 1361ef29c7
1 changed files with 9 additions and 5 deletions
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14
arch/x86/include/asm/fpu-internal.h
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@ -434,13 +434,17 @@ static inline fpu_switch_t switch_fpu_prepare(struct task_struct *old, struct ta
* If the task has used the math, pre-load the FPU on xsave processors
* or if the past 5 consecutive context-switches used math.
*/
fpu.preload = tsk_used_math(new) && (use_eager_fpu() ||
new->thread.fpu_counter > 5);
fpu.preload = tsk_used_math(new) &&
(use_eager_fpu() || new->thread.fpu_counter > 5);
if (__thread_has_fpu(old)) {
if (!__save_init_fpu(old))
cpu = ~0;
old->thread.fpu.last_cpu = cpu;
old->thread.fpu.has_fpu = 0; /* But leave fpu_owner_task! */
old->thread.fpu.last_cpu = ~0;
else
old->thread.fpu.last_cpu = cpu;
/* But leave fpu_owner_task! */
old->thread.fpu.has_fpu = 0;
/* Don't change CR0.TS if we just switch! */
if (fpu.preload) {