From: Andi Kleen <ak@suse.de>
Date: Tue, 26 Sep 2006 08:52:29 +0000 (+0200)
Subject: [PATCH] i386: Remove const case for rwlocks
X-Git-Tag: v2.6.19-rc1~1077^2~187
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1a015b5644ec6df0a2c4cbeff1f8a3d24ba0478e;p=linux-2.6

[PATCH] i386: Remove const case for rwlocks

rwlocks are now out of line, so it near never triggers.  Also it was
incompatible with the new dwarf2 unwinder because it had unannotiatable
push/pops.

Signed-off-by: Andi Kleen <ak@suse.de>
---

diff --git a/include/asm-i386/rwlock.h b/include/asm-i386/rwlock.h
index 87c069ccba..f40ccbd8cb 100644
--- a/include/asm-i386/rwlock.h
+++ b/include/asm-i386/rwlock.h
@@ -20,52 +20,18 @@
 #define RW_LOCK_BIAS		 0x01000000
 #define RW_LOCK_BIAS_STR	"0x01000000"
 
-#define __build_read_lock_ptr(rw, helper)   \
+#define __build_read_lock(rw, helper)   \
 	asm volatile(LOCK_PREFIX " subl $1,(%0)\n\t" \
 			"jns 1f\n" \
 			"call " helper "\n\t" \
 			"1:\n" \
 			::"a" (rw) : "memory")
 
-#define __build_read_lock_const(rw, helper)   \
-	asm volatile(LOCK_PREFIX " subl $1,%0\n\t" \
-			"jns 1f\n" \
-			"pushl %%eax\n\t" \
-			"leal %0,%%eax\n\t" \
-			"call " helper "\n\t" \
-			"popl %%eax\n\t" \
-			"1:\n" \
-			:"+m" (*(volatile int *)rw) : : "memory")
-
-#define __build_read_lock(rw, helper)	do { \
-						if (__builtin_constant_p(rw)) \
-							__build_read_lock_const(rw, helper); \
-						else \
-							__build_read_lock_ptr(rw, helper); \
-					} while (0)
-
-#define __build_write_lock_ptr(rw, helper) \
+#define __build_write_lock(rw, helper) \
 	asm volatile(LOCK_PREFIX " subl $" RW_LOCK_BIAS_STR ",(%0)\n\t" \
 			"jz 1f\n" \
 			"call " helper "\n\t" \
 			"1:\n" \
 			::"a" (rw) : "memory")
 
-#define __build_write_lock_const(rw, helper) \
-	asm volatile(LOCK_PREFIX " subl $" RW_LOCK_BIAS_STR ",%0\n\t" \
-			"jz 1f\n" \
-			"pushl %%eax\n\t" \
-			"leal %0,%%eax\n\t" \
-			"call " helper "\n\t" \
-			"popl %%eax\n\t" \
-			"1:\n" \
-			:"+m" (*(volatile int *)rw) : : "memory")
-
-#define __build_write_lock(rw, helper)	do { \
-						if (__builtin_constant_p(rw)) \
-							__build_write_lock_const(rw, helper); \
-						else \
-							__build_write_lock_ptr(rw, helper); \
-					} while (0)
-
 #endif