rwsem update

rwsem update

[David Howells]

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Hi Linus,

The attached patch fixes the compilation problems Andrew Morton has been
seeing with the rw-semaphores in the kernel when using gcc 2.95.3 with -O1.

David


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diff -uNr linux-2.5.17/include/asm-i386/rwsem.h linux-asmcons/include/asm-i386/rwsem.h
--- linux-2.5.17/include/asm-i386/rwsem.h	Wed May 15 11:20:57 2002
+++ linux-asmcons/include/asm-i386/rwsem.h	Wed May 22 08:41:23 2002
@@ -111,8 +111,8 @@
 		"  jmp       1b\n"
 		LOCK_SECTION_END
 		"# ending down_read\n\t"
-		: "+m"(sem->count)
-		: "a"(sem)
+		: "=m"(sem->count)
+		: "a"(sem), "m"(sem->count)
 		: "memory", "cc");
 }
 
@@ -126,8 +126,8 @@
 	tmp = RWSEM_ACTIVE_WRITE_BIAS;
 	__asm__ __volatile__(
 		"# beginning down_write\n\t"
-LOCK_PREFIX	"  xadd      %0,(%%eax)\n\t" /* subtract 0x0000ffff, returns the old value */
-		"  testl     %0,%0\n\t" /* was the count 0 before? */
+LOCK_PREFIX	"  xadd      %%edx,(%%eax)\n\t" /* subtract 0x0000ffff, returns the old value */
+		"  testl     %%edx,%%edx\n\t" /* was the count 0 before? */
 		"  jnz       2f\n\t" /* jump if we weren't granted the lock */
 		"1:\n\t"
 		LOCK_SECTION_START("")
@@ -138,8 +138,8 @@
 		"  jmp       1b\n"
 		LOCK_SECTION_END
 		"# ending down_write"
-		: "+d"(tmp), "+m"(sem->count)
-		: "a"(sem)
+		: "=m"(sem->count), "=d"(tmp)
+		: "a"(sem), "1"(tmp), "m"(sem->count)
 		: "memory", "cc");
 }
 
@@ -164,8 +164,8 @@
 		"  jmp       1b\n"
 		LOCK_SECTION_END
 		"# ending __up_read\n"
-		: /*"+m"(sem->count),*/ "+d"(tmp)
-		: "a"(sem)
+		: "=m"(sem->count), "=d"(tmp)
+		: "a"(sem), "1"(tmp), "m"(sem->count)
 		: "memory", "cc");
 }
 
@@ -190,8 +190,8 @@
 		"  jmp       1b\n"
 		LOCK_SECTION_END
 		"# ending __up_write\n"
-		: "+m"(sem->count)
-		: "a"(sem), "i"(-RWSEM_ACTIVE_WRITE_BIAS)
+		: "=m"(sem->count)
+		: "a"(sem), "i"(-RWSEM_ACTIVE_WRITE_BIAS), "m"(sem->count)
 		: "memory", "cc", "edx");
 }
 
@@ -202,8 +202,8 @@
 {
 	__asm__ __volatile__(
 LOCK_PREFIX	"addl %1,%0"
-		:"=m"(sem->count)
-		:"ir"(delta), "m"(sem->count));
+		: "=m"(sem->count)
+		: "ir"(delta), "m"(sem->count));
 }
 
 /*