# HG changeset patch
# User sos22@xxxxxxxxxxxxxxxxxxxx
# Node ID 5ffe3f16aa52a817e5656c24e9bea9a7033b3737
# Parent ea6d9f29dff5d429c0a7cb6c381628e6f2bb38e1
Make SMP alternatives work under xenolinux rather than just native,
since part of it seems to have gotten lost.
Signed-off-by: Steven Smith, sos22@xxxxxxxxx
diff -r ea6d9f29dff5 -r 5ffe3f16aa52
linux-2.6-xen-sparse/include/asm-xen/asm-i386/spinlock.h
--- a/linux-2.6-xen-sparse/include/asm-xen/asm-i386/spinlock.h Mon Oct 31
16:07:14 2005
+++ b/linux-2.6-xen-sparse/include/asm-xen/asm-i386/spinlock.h Tue Nov 1
12:38:20 2005
@@ -6,6 +6,7 @@
#include <asm/page.h>
#include <linux/config.h>
#include <linux/compiler.h>
+#include <asm/smp_alt.h>
asmlinkage int printk(const char * fmt, ...)
__attribute__ ((format (printf, 1, 2)));
@@ -47,8 +48,9 @@
#define spin_unlock_wait(x) do { barrier(); } while(spin_is_locked(x))
#define spin_lock_string \
- "\n1:\t" \
- "lock ; decb %0\n\t" \
+ "1:\n" \
+ LOCK \
+ "decb %0\n\t" \
"jns 3f\n" \
"2:\t" \
"rep;nop\n\t" \
@@ -58,8 +60,9 @@
"3:\n\t"
#define spin_lock_string_flags \
- "\n1:\t" \
- "lock ; decb %0\n\t" \
+ "1:\n" \
+ LOCK \
+ "decb %0\n\t" \
"jns 4f\n\t" \
"2:\t" \
"testl $0x200, %1\n\t" \
@@ -121,10 +124,34 @@
static inline int _raw_spin_trylock(spinlock_t *lock)
{
char oldval;
- __asm__ __volatile__(
- "xchgb %b0,%1"
+#ifdef CONFIG_SMP_ALTERNATIVES
+ __asm__ __volatile__(
+ "1:movb %1,%b0\n"
+ "movb $0,%1\n"
+ "2:"
+ ".section __smp_alternatives,\"a\"\n"
+ ".long 1b\n"
+ ".long 3f\n"
+ ".previous\n"
+ ".section __smp_replacements,\"a\"\n"
+ "3: .byte 2b - 1b\n"
+ ".byte 5f-4f\n"
+ ".byte 0\n"
+ ".byte 6f-5f\n"
+ ".byte -1\n"
+ "4: xchgb %b0,%1\n"
+ "5: movb %1,%b0\n"
+ "movb $0,%1\n"
+ "6:\n"
+ ".previous\n"
:"=q" (oldval), "=m" (lock->slock)
:"0" (0) : "memory");
+#else
+ __asm__ __volatile__(
+ "xchgb %b0,%1\n"
+ :"=q" (oldval), "=m" (lock->slock)
+ :"0" (0) : "memory");
+#endif
return oldval > 0;
}
@@ -225,8 +252,8 @@
__build_write_lock(rw, "__write_lock_failed");
}
-#define _raw_read_unlock(rw) asm volatile("lock ; incl %0" :"=m"
((rw)->lock) : : "memory")
-#define _raw_write_unlock(rw) asm volatile("lock ; addl $" RW_LOCK_BIAS_STR
",%0":"=m" ((rw)->lock) : : "memory")
+#define _raw_read_unlock(rw) asm volatile(LOCK "incl %0" :"=m" ((rw)->lock)
: : "memory")
+#define _raw_write_unlock(rw) asm volatile(LOCK "addl $" RW_LOCK_BIAS_STR
",%0":"=m" ((rw)->lock) : : "memory")
static inline int _raw_read_trylock(rwlock_t *lock)
{
_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog
|
Home