vserver 1.9.5.x5

[linux-2.6.git] / arch / mips / kernel / semaphore.c

diff --git a/arch/mips/kernel/semaphore.c b/arch/mips/kernel/semaphore.c
index 4197b41..9c40fe5 100644 (file)
--- a/arch/mips/kernel/semaphore.c
+++ b/arch/mips/kernel/semaphore.c
@@ -15,16 +15,14 @@
  * indicate that some process(es) are waiting for the semaphore.
  */
 
-#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/sched.h>
 #include <linux/init.h>
 #include <asm/atomic.h>
-#include <asm/semaphore.h>
+#include <asm/cpu-features.h>
 #include <asm/errno.h>
-
-#ifdef CONFIG_CPU_HAS_LLSC
-
+#include <asm/semaphore.h>
+#include <asm/war.h>
 /*
  * Atomically update sem->count.
  * This does the equivalent of the following:
@@ -33,50 +31,51 @@
  *     tmp = MAX(old_count, 0) + incr;
  *     sem->count = tmp;
  *     return old_count;
- */
-static inline int __sem_update_count(struct semaphore *sem, int incr)
-{
-       int old_count, tmp;
-
-       __asm__ __volatile__(
-       "1:     ll      %0, %2                                  \n"
-       "       sra     %1, %0, 31                              \n"
-       "       not     %1                                      \n"
-       "       and     %1, %0, %1                              \n"
-       "       add     %1, %1, %3                              \n"
-       "       sc      %1, %2                                  \n"
-       "       beqz    %1, 1b                                  \n"
-       : "=&r" (old_count), "=&r" (tmp), "=m" (sem->count)
-       : "r" (incr), "m" (sem->count));
-
-       return old_count;
-}
-
-#else
-
-/*
+ *
  * On machines without lld/scd we need a spinlock to make the manipulation of
  * sem->count and sem->waking atomic.  Scalability isn't an issue because
  * this lock is used on UP only so it's just an empty variable.
  */
-static spinlock_t semaphore_lock = SPIN_LOCK_UNLOCKED;
-
 static inline int __sem_update_count(struct semaphore *sem, int incr)
 {
-       unsigned long flags;
        int old_count, tmp;
 
-       spin_lock_irqsave(&semaphore_lock, flags);
-       old_count = atomic_read(&sem->count);
-       tmp = max_t(int, old_count, 0) + incr;
-       atomic_set(&sem->count, tmp);
-       spin_unlock_irqrestore(&semaphore_lock, flags);
+       if (cpu_has_llsc && R10000_LLSC_WAR) {
+               __asm__ __volatile__(
+               "1:     ll      %0, %2                                  \n"
+               "       sra     %1, %0, 31                              \n"
+               "       not     %1                                      \n"
+               "       and     %1, %0, %1                              \n"
+               "       add     %1, %1, %3                              \n"
+               "       sc      %1, %2                                  \n"
+               "       beqzl   %1, 1b                                  \n"
+               : "=&r" (old_count), "=&r" (tmp), "=m" (sem->count)
+               : "r" (incr), "m" (sem->count));
+       } else if (cpu_has_llsc) {
+               __asm__ __volatile__(
+               "1:     ll      %0, %2                                  \n"
+               "       sra     %1, %0, 31                              \n"
+               "       not     %1                                      \n"
+               "       and     %1, %0, %1                              \n"
+               "       add     %1, %1, %3                              \n"
+               "       sc      %1, %2                                  \n"
+               "       beqz    %1, 1b                                  \n"
+               : "=&r" (old_count), "=&r" (tmp), "=m" (sem->count)
+               : "r" (incr), "m" (sem->count));
+       } else {
+               static DEFINE_SPINLOCK(semaphore_lock);
+               unsigned long flags;
+
+               spin_lock_irqsave(&semaphore_lock, flags);
+               old_count = atomic_read(&sem->count);
+               tmp = max_t(int, old_count, 0) + incr;
+               atomic_set(&sem->count, tmp);
+               spin_unlock_irqrestore(&semaphore_lock, flags);
+       }
 
        return old_count;
 }
 
-#endif
-
 void __up(struct semaphore *sem)
 {
        /*