From: tip-bot for Rik van Riel <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: bp@suse.de, riel@redhat.com, mingo@kernel.org,
tglx@linutronix.de, hpa@zytor.com, linux-kernel@vger.kernel.org,
oleg@redhat.com, torvalds@linux-foundation.org
Subject: [tip:x86/fpu] x86/fpu: Use an explicit if/ else in switch_fpu_prepare()
Date: Thu, 19 Feb 2015 03:33:50 -0800 [thread overview]
Message-ID: <tip-1361ef29c7e49ae7cf37220c25fac1904b77f71a@git.kernel.org> (raw)
In-Reply-To: <1423252925-14451-7-git-send-email-riel@redhat.com>
Commit-ID: 1361ef29c7e49ae7cf37220c25fac1904b77f71a
Gitweb: http://git.kernel.org/tip/1361ef29c7e49ae7cf37220c25fac1904b77f71a
Author: Rik van Riel <riel@redhat.com>
AuthorDate: Fri, 6 Feb 2015 15:02:03 -0500
Committer: Borislav Petkov <bp@suse.de>
CommitDate: Thu, 19 Feb 2015 11:15:54 +0100
x86/fpu: Use an explicit if/else in switch_fpu_prepare()
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>
---
arch/x86/include/asm/fpu-internal.h | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/asm/fpu-internal.h b/arch/x86/include/asm/fpu-internal.h
index 9c27f44..04c2807 100644
--- a/arch/x86/include/asm/fpu-internal.h
+++ b/arch/x86/include/asm/fpu-internal.h
@@ -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) {
next prev parent reply other threads:[~2015-02-19 11:34 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-02-06 20:01 [PATCH 0/8] x86,fpu: various small FPU cleanups and optimizations riel
2015-02-06 20:01 ` [PATCH 1/8] x86, fpu: unlazy_fpu: don't reset thread.fpu_counter riel
2015-02-16 17:04 ` Borislav Petkov
2015-02-16 17:58 ` Rik van Riel
2015-02-16 18:14 ` Oleg Nesterov
2015-02-16 18:16 ` Borislav Petkov
2015-02-19 11:32 ` [tip:x86/fpu] x86/fpu: Don't " tip-bot for Oleg Nesterov
2015-02-06 20:01 ` [PATCH 2/8] x86, fpu: unlazy_fpu: don't do __thread_fpu_end() if use_eager_fpu() riel
2015-02-16 20:25 ` Borislav Petkov
2015-02-17 10:47 ` Oleg Nesterov
2015-02-17 12:09 ` Borislav Petkov
2015-02-19 11:32 ` [tip:x86/fpu] x86/fpu: Don't " tip-bot for Oleg Nesterov
2015-02-06 20:02 ` [PATCH 3/8] x86, fpu: kill save_init_fpu(), change math_error() to use unlazy_fpu() riel
2015-02-16 21:09 ` Borislav Petkov
2015-02-16 21:30 ` Rik van Riel
2015-02-17 10:58 ` Oleg Nesterov
2015-02-19 11:32 ` [tip:x86/fpu] x86/fpu: Change math_error() to use unlazy_fpu(), kill (now) unused save_init_fpu() tip-bot for Oleg Nesterov
2015-02-06 20:02 ` [PATCH 4/8] x86,fpu: move lazy restore functions up a few lines riel
2015-02-19 11:33 ` [tip:x86/fpu] x86/fpu: Move " tip-bot for Rik van Riel
2015-02-06 20:02 ` [PATCH 5/8] x86,fpu: introduce task_disable_lazy_fpu_restore helper riel
2015-02-19 11:33 ` [tip:x86/fpu] x86/fpu: Introduce task_disable_lazy_fpu_restore() helper tip-bot for Rik van Riel
2015-02-06 20:02 ` [PATCH 6/8] x86,fpu: use an explicit if/else in switch_fpu_prepare riel
2015-02-17 8:44 ` Borislav Petkov
2015-02-19 11:33 ` tip-bot for Rik van Riel [this message]
2015-02-06 20:02 ` [PATCH 7/8] x86,fpu: use disable_task_lazy_fpu_restore helper riel
2015-02-17 9:00 ` Borislav Petkov
2015-02-17 11:04 ` Oleg Nesterov
2015-02-17 12:11 ` Borislav Petkov
2015-02-19 11:34 ` [tip:x86/fpu] x86/fpu: Use task_disable_lazy_fpu_restore() helper tip-bot for Rik van Riel
2015-02-06 20:02 ` [PATCH 8/8] x86,fpu: also check fpu_lazy_restore when use_eager_fpu riel
2015-02-19 11:34 ` [tip:x86/fpu] x86/fpu: Also check fpu_lazy_restore() when use_eager_fpu() tip-bot for Rik van Riel
2015-02-16 15:26 ` [PATCH 0/8] x86,fpu: various small FPU cleanups and optimizations Rik van Riel
2015-02-16 16:00 ` Borislav Petkov
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