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Diffstat (limited to 'arch/s390/lib/spinlock.c')
-rw-r--r--arch/s390/lib/spinlock.c54
1 files changed, 37 insertions, 17 deletions
diff --git a/arch/s390/lib/spinlock.c b/arch/s390/lib/spinlock.c
index 81c53440b3e6..a81a01c44927 100644
--- a/arch/s390/lib/spinlock.c
+++ b/arch/s390/lib/spinlock.c
@@ -15,6 +15,7 @@
#include <linux/percpu.h>
#include <linux/io.h>
#include <asm/alternative.h>
+#include <asm/asm.h>
int spin_retry = -1;
@@ -75,25 +76,44 @@ static inline int arch_load_niai4(int *lock)
int owner;
asm_inline volatile(
- ALTERNATIVE("nop", ".insn rre,0xb2fa0000,4,0", 49) /* NIAI 4 */
- " l %0,%1\n"
- : "=d" (owner) : "Q" (*lock) : "memory");
+ ALTERNATIVE("nop", ".insn rre,0xb2fa0000,4,0", ALT_FACILITY(49)) /* NIAI 4 */
+ " l %[owner],%[lock]\n"
+ : [owner] "=d" (owner) : [lock] "R" (*lock) : "memory");
return owner;
}
-static inline int arch_cmpxchg_niai8(int *lock, int old, int new)
+#ifdef __HAVE_ASM_FLAG_OUTPUTS__
+
+static inline int arch_try_cmpxchg_niai8(int *lock, int old, int new)
+{
+ int cc;
+
+ asm_inline volatile(
+ ALTERNATIVE("nop", ".insn rre,0xb2fa0000,8,0", ALT_FACILITY(49)) /* NIAI 8 */
+ " cs %[old],%[new],%[lock]\n"
+ : [old] "+d" (old), [lock] "+Q" (*lock), "=@cc" (cc)
+ : [new] "d" (new)
+ : "memory");
+ return cc == 0;
+}
+
+#else /* __HAVE_ASM_FLAG_OUTPUTS__ */
+
+static inline int arch_try_cmpxchg_niai8(int *lock, int old, int new)
{
int expected = old;
asm_inline volatile(
- ALTERNATIVE("nop", ".insn rre,0xb2fa0000,8,0", 49) /* NIAI 8 */
- " cs %0,%3,%1\n"
- : "=d" (old), "=Q" (*lock)
- : "0" (old), "d" (new), "Q" (*lock)
+ ALTERNATIVE("nop", ".insn rre,0xb2fa0000,8,0", ALT_FACILITY(49)) /* NIAI 8 */
+ " cs %[old],%[new],%[lock]\n"
+ : [old] "+d" (old), [lock] "+Q" (*lock)
+ : [new] "d" (new)
: "cc", "memory");
return expected == old;
}
+#endif /* __HAVE_ASM_FLAG_OUTPUTS__ */
+
static inline struct spin_wait *arch_spin_decode_tail(int lock)
{
int ix, cpu;
@@ -119,7 +139,7 @@ static inline void arch_spin_lock_queued(arch_spinlock_t *lp)
struct spin_wait *node, *next;
int lockval, ix, node_id, tail_id, old, new, owner, count;
- ix = S390_lowcore.spinlock_index++;
+ ix = get_lowcore()->spinlock_index++;
barrier();
lockval = SPINLOCK_LOCKVAL; /* cpu + 1 */
node = this_cpu_ptr(&spin_wait[ix]);
@@ -127,8 +147,8 @@ static inline void arch_spin_lock_queued(arch_spinlock_t *lp)
node_id = node->node_id;
/* Enqueue the node for this CPU in the spinlock wait queue */
+ old = READ_ONCE(lp->lock);
while (1) {
- old = READ_ONCE(lp->lock);
if ((old & _Q_LOCK_CPU_MASK) == 0 &&
(old & _Q_LOCK_STEAL_MASK) != _Q_LOCK_STEAL_MASK) {
/*
@@ -139,7 +159,7 @@ static inline void arch_spin_lock_queued(arch_spinlock_t *lp)
* waiter will get the lock.
*/
new = (old ? (old + _Q_LOCK_STEAL_ADD) : 0) | lockval;
- if (__atomic_cmpxchg_bool(&lp->lock, old, new))
+ if (arch_try_cmpxchg(&lp->lock, &old, new))
/* Got the lock */
goto out;
/* lock passing in progress */
@@ -147,7 +167,7 @@ static inline void arch_spin_lock_queued(arch_spinlock_t *lp)
}
/* Make the node of this CPU the new tail. */
new = node_id | (old & _Q_LOCK_MASK);
- if (__atomic_cmpxchg_bool(&lp->lock, old, new))
+ if (arch_try_cmpxchg(&lp->lock, &old, new))
break;
}
/* Set the 'next' pointer of the tail node in the queue */
@@ -184,7 +204,7 @@ static inline void arch_spin_lock_queued(arch_spinlock_t *lp)
if (!owner) {
tail_id = old & _Q_TAIL_MASK;
new = ((tail_id != node_id) ? tail_id : 0) | lockval;
- if (__atomic_cmpxchg_bool(&lp->lock, old, new))
+ if (arch_try_cmpxchg(&lp->lock, &old, new))
/* Got the lock */
break;
continue;
@@ -205,7 +225,7 @@ static inline void arch_spin_lock_queued(arch_spinlock_t *lp)
}
out:
- S390_lowcore.spinlock_index--;
+ get_lowcore()->spinlock_index--;
}
static inline void arch_spin_lock_classic(arch_spinlock_t *lp)
@@ -226,7 +246,7 @@ static inline void arch_spin_lock_classic(arch_spinlock_t *lp)
/* Try to get the lock if it is free. */
if (!owner) {
new = (old & _Q_TAIL_MASK) | lockval;
- if (arch_cmpxchg_niai8(&lp->lock, old, new)) {
+ if (arch_try_cmpxchg_niai8(&lp->lock, old, new)) {
/* Got the lock */
return;
}
@@ -258,7 +278,7 @@ int arch_spin_trylock_retry(arch_spinlock_t *lp)
owner = READ_ONCE(lp->lock);
/* Try to get the lock if it is free. */
if (!owner) {
- if (__atomic_cmpxchg_bool(&lp->lock, 0, cpu))
+ if (arch_try_cmpxchg(&lp->lock, &owner, cpu))
return 1;
}
}
@@ -300,7 +320,7 @@ void arch_write_lock_wait(arch_rwlock_t *rw)
while (1) {
old = READ_ONCE(rw->cnts);
if ((old & 0x1ffff) == 0 &&
- __atomic_cmpxchg_bool(&rw->cnts, old, old | 0x10000))
+ arch_try_cmpxchg(&rw->cnts, &old, old | 0x10000))
/* Got the lock */
break;
barrier();