linux-kernel - [PATCH 6/6] x86,fpu: remove redundant increments of fpu

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Date:	Mon,  2 Feb 2015 13:00:51 -0500
From:	riel@...hat.com
To:	oleg@...hat.com
Cc:	dave.hansen@...ux.intel.com, sbsiddha@...il.com,
	luto@...capital.net, tglx@...utronix.de, mingo@...hat.com,
	hpa@...or.com, fenghua.yu@...el.com, x86@...nel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH 6/6] x86,fpu: remove redundant increments of fpu_counter

From: Rik van Riel <riel@...hat.com>

fpu.preload only gets set if new->thread.fpu_counter is already
larger than 5. Incrementing it further does absolutely nothing.
Remove those lines.

Signed-off-by: Rik van Riel <riel@...hat.com>
---
 arch/x86/include/asm/fpu-internal.h | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/x86/include/asm/fpu-internal.h b/arch/x86/include/asm/fpu-internal.h
index 085903415cbd..88df5808a2db 100644
--- a/arch/x86/include/asm/fpu-internal.h
+++ b/arch/x86/include/asm/fpu-internal.h
@@ -447,7 +447,6 @@ static inline fpu_switch_t switch_fpu_prepare(struct task_struct *old, struct ta
 
 		/* Don't change CR0.TS if we just switch! */
 		if (fpu.preload) {
-			new->thread.fpu_counter++;
 			__thread_set_has_fpu(new);
 			prefetch(new->thread.fpu.state);
 		} else if (!use_eager_fpu())
@@ -456,7 +455,6 @@ static inline fpu_switch_t switch_fpu_prepare(struct task_struct *old, struct ta
 		old->thread.fpu_counter = 0;
 		task_disable_lazy_fpu_restore(old);
 		if (fpu.preload) {
-			new->thread.fpu_counter++;
 			if (fpu_lazy_restore(new, cpu))
 				fpu.preload = 0;
 			else
-- 
1.9.3

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