X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Fasm-x86_64%2Frwlock.h;fp=include%2Fasm-x86_64%2Frwlock.h;h=9942cc393064a825d6f64159b9135b599f592b44;hb=64ba3f394c830ec48a1c31b53dcae312c56f1604;hp=28a080d231191ff32e5d97c030923943bb0fb4d4;hpb=be1e6109ac94a859551f8e1774eb9a8469fe055c;p=linux-2.6.git

diff --git a/include/asm-x86_64/rwlock.h b/include/asm-x86_64/rwlock.h
index 28a080d23..9942cc393 100644
--- a/include/asm-x86_64/rwlock.h
+++ b/include/asm-x86_64/rwlock.h
@@ -18,21 +18,69 @@
 #ifndef _ASM_X86_64_RWLOCK_H
 #define _ASM_X86_64_RWLOCK_H
 
+#include <linux/stringify.h>
+
 #define RW_LOCK_BIAS		 0x01000000
-#define RW_LOCK_BIAS_STR	 "0x01000000"
+#define RW_LOCK_BIAS_STR	"0x01000000"
+
+#define __build_read_lock_ptr(rw, helper)   \
+	asm volatile(LOCK "subl $1,(%0)\n\t" \
+		     "js 2f\n" \
+		     "1:\n" \
+		    LOCK_SECTION_START("") \
+		     "2:\tcall " helper "\n\t" \
+		     "jmp 1b\n" \
+		    LOCK_SECTION_END \
+		     ::"a" (rw) : "memory")
 
-#define __build_read_lock(rw)   \
-	asm volatile(LOCK_PREFIX "subl $1,(%0)\n\t" \
-		     "jns 1f\n" \
-		     "call __read_lock_failed\n" \
+#define __build_read_lock_const(rw, helper)   \
+	asm volatile(LOCK "subl $1,%0\n\t" \
+		     "js 2f\n" \
 		     "1:\n" \
-		     ::"D" (rw), "i" (RW_LOCK_BIAS) : "memory")
+		    LOCK_SECTION_START("") \
+		     "2:\tpushq %%rax\n\t" \
+		     "leaq %0,%%rax\n\t" \
+		     "call " helper "\n\t" \
+		     "popq %%rax\n\t" \
+		     "jmp 1b\n" \
+		    LOCK_SECTION_END \
+		     :"=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(rw) \
-	asm volatile(LOCK_PREFIX "subl %1,(%0)\n\t" \
-		     "jz 1f\n" \
-		     "\tcall __write_lock_failed\n\t" \
+#define __build_write_lock_ptr(rw, helper) \
+	asm volatile(LOCK "subl $" RW_LOCK_BIAS_STR ",(%0)\n\t" \
+		     "jnz 2f\n" \
 		     "1:\n" \
-		     ::"D" (rw), "i" (RW_LOCK_BIAS) : "memory")
+		     LOCK_SECTION_START("") \
+		     "2:\tcall " helper "\n\t" \
+		     "jmp 1b\n" \
+		     LOCK_SECTION_END \
+		     ::"a" (rw) : "memory")
+
+#define __build_write_lock_const(rw, helper) \
+	asm volatile(LOCK "subl $" RW_LOCK_BIAS_STR ",%0\n\t" \
+		     "jnz 2f\n" \
+		     "1:\n" \
+		    LOCK_SECTION_START("") \
+		     "2:\tpushq %%rax\n\t" \
+		     "leaq %0,%%rax\n\t" \
+		     "call " helper "\n\t" \
+		     "popq %%rax\n\t" \
+		     "jmp 1b\n" \
+		    LOCK_SECTION_END \
+		     :"=m" (*((volatile long *)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