linux-kernel - [PATCH v2 3/8] x86: Drop 4 unnecessary calls to __pa

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Date:	Thu, 11 Oct 2012 13:50:08 -0700
From:	Alexander Duyck <alexander.h.duyck@...el.com>
To:	tglx@...utronix.de, mingo@...hat.com, hpa@...or.com,
	andi@...stfloor.org
Cc:	linux-kernel@...r.kernel.org, x86@...nel.org,
	Alexander Duyck <alexander.h.duyck@...el.com>
Subject: [PATCH v2 3/8] x86: Drop 4 unnecessary calls to __pa_symbol

While debugging the __pa_symbol inline patch I found that there were a couple
spots where __pa_symbol was used as follows:
__pa_symbol(x) - __pa_symbol(y)

The compiler had reduced them to:
x - y

Since we also support a debug case where __pa_symbol is a function call it
would probably be useful to just change the two cases I found so that they are
always just treated as "x - y".  As such I am casting the values to
phys_addr_t and then doing simple subtraction so that the correct type and
value is returned.

Signed-off-by: Alexander Duyck <alexander.h.duyck@...el.com>
---

 arch/x86/kernel/head32.c |    4 ++--
 arch/x86/kernel/head64.c |    4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/head32.c b/arch/x86/kernel/head32.c
index c18f59d..f15db0c 100644
--- a/arch/x86/kernel/head32.c
+++ b/arch/x86/kernel/head32.c
@@ -30,8 +30,8 @@ static void __init i386_default_early_setup(void)
 
 void __init i386_start_kernel(void)
 {
-	memblock_reserve(__pa_symbol(&_text),
-			 __pa_symbol(&__bss_stop) - __pa_symbol(&_text));
+	memblock_reserve(__pa_symbol(_text),
+			 (phys_addr_t)__bss_stop - (phys_addr_t)_text);
 
 #ifdef CONFIG_BLK_DEV_INITRD
 	/* Reserve INITRD */
diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 037df57..42f5df1 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -97,8 +97,8 @@ void __init x86_64_start_reservations(char *real_mode_data)
 {
 	copy_bootdata(__va(real_mode_data));
 
-	memblock_reserve(__pa_symbol(&_text),
-			 __pa_symbol(&__bss_stop) - __pa_symbol(&_text));
+	memblock_reserve(__pa_symbol(_text),
+			 (phys_addr_t)__bss_stop - (phys_addr_t)_text);
 
 #ifdef CONFIG_BLK_DEV_INITRD
 	/* Reserve INITRD */

--
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