From: James Yang <James.Yang@freescale.com>
To: <benh@kernel.crashing.org>, <scottwood@freescale.com>
Cc: James Yang <James.Yang@freescale.com>, linuxppc-dev@lists.ozlabs.org
Subject: [PATCH] powerpc/ppc64: remove __volatile__ in get_current()
Date: Fri, 9 Aug 2013 23:49:22 -0500 [thread overview]
Message-ID: <1376110162-3462-1-git-send-email-James.Yang@freescale.com> (raw)
Uses of get_current() that normally get optimized away still result in
a load instruction of the current pointer in 64-bit because the inline
asm uses __volatile__. This patch removes __volatile__ so that nop-ed
uses of get_current() don't actually result in a load of the pointer.
Signed-off-by: James Yang <James.Yang@freescale.com>
---
arch/powerpc/include/asm/current.h | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/arch/powerpc/include/asm/current.h b/arch/powerpc/include/asm/current.h
index e2c7f06..bb250c8 100644
--- a/arch/powerpc/include/asm/current.h
+++ b/arch/powerpc/include/asm/current.h
@@ -19,7 +19,7 @@ static inline struct task_struct *get_current(void)
{
struct task_struct *task;
- __asm__ __volatile__("ld %0,%1(13)"
+ __asm__ ("ld %0,%1(13)"
: "=r" (task)
: "i" (offsetof(struct paca_struct, __current)));
--
1.7.0.4
next reply other threads:[~2013-08-10 4:49 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-10 4:49 James Yang [this message]
2013-08-23 23:40 ` [PATCH] powerpc/ppc64: remove __volatile__ in get_current() James Yang
2013-08-23 23:48 ` Scott Wood
2013-08-24 0:22 ` Benjamin Herrenschmidt
2013-08-24 0:20 ` Benjamin Herrenschmidt
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