Re: + spin_lock_irq-enable-interrupts-while-spinning-i386-implementation.patch added to -mm tree

Andrew Morton
2007-01-07T07:27:24Z

On Sat, 06 Jan 2007 14:35:53 -0800
Daniel Walker <dwalker@mvista.com> wrote:

> On Wed, 2007-01-03 at 13:12 -0800, akpm@osdl.org wrote:
> > -# define __raw_spin_lock_irq(lock) __raw_spin_lock(lock)
> > +
> > +static inline void __raw_spin_lock_irq(raw_spinlock_t *lock)
> > +{
> > + asm volatile("\n1:\t"
> > + LOCK_PREFIX " ; decb %0\n\t"
> > + "jns 3f\n"
> > + STI_STRING "\n"
> > + "2:\t"
> > + "rep;nop\n\t"
> > + "cmpb $0,%0\n\t"
> > + "jle 2b\n\t"
> > + CLI_STRING "\n"
> > + "jmp 1b\n"
> > + "3:\n\t"
> > + : "+m" (lock->slock) : : "memory");
> > +}
> > #endif
> >
>
> This doesn't compile when CONFIG_PARAVIRT is enabled. It changes the
> CLI_STRING and STI_STRING values.
>

diff -puN include/asm-i386/spinlock.h~spin_lock_irq-enable-interrupts-while-spinning-i386-implementation-fix include/asm-i386/spinlock.h
--- a/include/asm-i386/spinlock.h~spin_lock_irq-enable-interrupts-while-spinning-i386-implementation-fix
+++ a/include/asm-i386/spinlock.h
@@ -86,17 +86,19 @@ static inline void __raw_spin_lock_flags
static inline void __raw_spin_lock_irq(raw_spinlock_t *lock)
{
asm volatile("\n1:\t"
- LOCK_PREFIX " ; decb %0\n\t"
+ LOCK_PREFIX " ; decb %[slock]\n\t"
"jns 3f\n"
STI_STRING "\n"
"2:\t"
"rep;nop\n\t"
- "cmpb $0,%0\n\t"
+ "cmpb $0,%[slock]\n\t"
"jle 2b\n\t"
CLI_STRING "\n"
"jmp 1b\n"
"3:\n\t"
- : "+m" (lock->slock) : : "memory");
+ : [slock] "+m" (lock->slock)
+ : __CLI_STI_INPUT_ARGS
+ : "memory" CLI_STI_CLOBBERS);
}
#endif

diff -puN include/asm-i386/paravirt.h~spin_lock_irq-enable-interrupts-while-spinning-i386-implementation-fix include/asm-i386/paravirt.h
--- a/include/asm-i386/paravirt.h~spin_lock_irq-enable-interrupts-while-spinning-i386-implementation-fix
+++ a/include/asm-i386/paravirt.h
@@ -509,10 +509,10 @@ static inline unsigned long __raw_local_
"popl %%edx; popl %%ecx", \
PARAVIRT_IRQ_ENABLE, CLBR_EAX)
#define CLI_STI_CLOBBERS , "%eax"
-#define CLI_STI_INPUT_ARGS \
- , \
+#define __CLI_STI_INPUT_ARGS \
[irq_disable] "i" (offsetof(struct paravirt_ops, irq_disable)), \
[irq_enable] "i" (offsetof(struct paravirt_ops, irq_enable))
+#define CLI_STI_INPUT_ARGS , __CLI_STI_INPUT_ARGS

#else /* __ASSEMBLY__ */

_