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Diffstat (limited to 'arch/arm/include/asm/atomic.h')
-rw-r--r--arch/arm/include/asm/atomic.h373
1 files changed, 319 insertions, 54 deletions
diff --git a/arch/arm/include/asm/atomic.h b/arch/arm/include/asm/atomic.h
index d0daeab2234..3040359094d 100644
--- a/arch/arm/include/asm/atomic.h
+++ b/arch/arm/include/asm/atomic.h
@@ -12,8 +12,11 @@
#define __ASM_ARM_ATOMIC_H
#include <linux/compiler.h>
+#include <linux/prefetch.h>
#include <linux/types.h>
-#include <asm/system.h>
+#include <linux/irqflags.h>
+#include <asm/barrier.h>
+#include <asm/cmpxchg.h>
#define ATOMIC_INIT(i) { (i) }
@@ -24,7 +27,7 @@
* strex/ldrex monitor on some implementations. The reason we can use it for
* atomic_set() is the clrex or dummy strex done on every exception return.
*/
-#define atomic_read(v) ((v)->counter)
+#define atomic_read(v) (*(volatile int *)&(v)->counter)
#define atomic_set(v,i) (((v)->counter) = (i))
#if __LINUX_ARM_ARCH__ >= 6
@@ -39,13 +42,14 @@ static inline void atomic_add(int i, atomic_t *v)
unsigned long tmp;
int result;
+ prefetchw(&v->counter);
__asm__ __volatile__("@ atomic_add\n"
-"1: ldrex %0, [%2]\n"
-" add %0, %0, %3\n"
-" strex %1, %0, [%2]\n"
+"1: ldrex %0, [%3]\n"
+" add %0, %0, %4\n"
+" strex %1, %0, [%3]\n"
" teq %1, #0\n"
" bne 1b"
- : "=&r" (result), "=&r" (tmp)
+ : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter)
: "r" (&v->counter), "Ir" (i)
: "cc");
}
@@ -56,14 +60,15 @@ static inline int atomic_add_return(int i, atomic_t *v)
int result;
smp_mb();
+ prefetchw(&v->counter);
__asm__ __volatile__("@ atomic_add_return\n"
-"1: ldrex %0, [%2]\n"
-" add %0, %0, %3\n"
-" strex %1, %0, [%2]\n"
+"1: ldrex %0, [%3]\n"
+" add %0, %0, %4\n"
+" strex %1, %0, [%3]\n"
" teq %1, #0\n"
" bne 1b"
- : "=&r" (result), "=&r" (tmp)
+ : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter)
: "r" (&v->counter), "Ir" (i)
: "cc");
@@ -77,13 +82,14 @@ static inline void atomic_sub(int i, atomic_t *v)
unsigned long tmp;
int result;
+ prefetchw(&v->counter);
__asm__ __volatile__("@ atomic_sub\n"
-"1: ldrex %0, [%2]\n"
-" sub %0, %0, %3\n"
-" strex %1, %0, [%2]\n"
+"1: ldrex %0, [%3]\n"
+" sub %0, %0, %4\n"
+" strex %1, %0, [%3]\n"
" teq %1, #0\n"
" bne 1b"
- : "=&r" (result), "=&r" (tmp)
+ : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter)
: "r" (&v->counter), "Ir" (i)
: "cc");
}
@@ -94,14 +100,15 @@ static inline int atomic_sub_return(int i, atomic_t *v)
int result;
smp_mb();
+ prefetchw(&v->counter);
__asm__ __volatile__("@ atomic_sub_return\n"
-"1: ldrex %0, [%2]\n"
-" sub %0, %0, %3\n"
-" strex %1, %0, [%2]\n"
+"1: ldrex %0, [%3]\n"
+" sub %0, %0, %4\n"
+" strex %1, %0, [%3]\n"
" teq %1, #0\n"
" bne 1b"
- : "=&r" (result), "=&r" (tmp)
+ : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter)
: "r" (&v->counter), "Ir" (i)
: "cc");
@@ -112,17 +119,19 @@ static inline int atomic_sub_return(int i, atomic_t *v)
static inline int atomic_cmpxchg(atomic_t *ptr, int old, int new)
{
- unsigned long oldval, res;
+ int oldval;
+ unsigned long res;
smp_mb();
+ prefetchw(&ptr->counter);
do {
__asm__ __volatile__("@ atomic_cmpxchg\n"
- "ldrex %1, [%2]\n"
+ "ldrex %1, [%3]\n"
"mov %0, #0\n"
- "teq %1, %3\n"
- "strexeq %0, %4, [%2]\n"
- : "=&r" (res), "=&r" (oldval)
+ "teq %1, %4\n"
+ "strexeq %0, %5, [%3]\n"
+ : "=&r" (res), "=&r" (oldval), "+Qo" (ptr->counter)
: "r" (&ptr->counter), "Ir" (old), "r" (new)
: "cc");
} while (res);
@@ -132,19 +141,31 @@ static inline int atomic_cmpxchg(atomic_t *ptr, int old, int new)
return oldval;
}
-static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
- unsigned long tmp, tmp2;
+ int oldval, newval;
+ unsigned long tmp;
- __asm__ __volatile__("@ atomic_clear_mask\n"
-"1: ldrex %0, [%2]\n"
-" bic %0, %0, %3\n"
-" strex %1, %0, [%2]\n"
-" teq %1, #0\n"
-" bne 1b"
- : "=&r" (tmp), "=&r" (tmp2)
- : "r" (addr), "Ir" (mask)
+ smp_mb();
+ prefetchw(&v->counter);
+
+ __asm__ __volatile__ ("@ atomic_add_unless\n"
+"1: ldrex %0, [%4]\n"
+" teq %0, %5\n"
+" beq 2f\n"
+" add %1, %0, %6\n"
+" strex %2, %1, [%4]\n"
+" teq %2, #0\n"
+" bne 1b\n"
+"2:"
+ : "=&r" (oldval), "=&r" (newval), "=&r" (tmp), "+Qo" (v->counter)
+ : "r" (&v->counter), "r" (u), "r" (a)
: "cc");
+
+ if (oldval != u)
+ smp_mb();
+
+ return oldval;
}
#else /* ARM_ARCH_6 */
@@ -195,29 +216,19 @@ static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
return ret;
}
-static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
-{
- unsigned long flags;
-
- raw_local_irq_save(flags);
- *addr &= ~mask;
- raw_local_irq_restore(flags);
-}
-
-#endif /* __LINUX_ARM_ARCH__ */
-
-#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
-
-static inline int atomic_add_unless(atomic_t *v, int a, int u)
+static inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
int c, old;
c = atomic_read(v);
while (c != u && (old = atomic_cmpxchg((v), c, c + a)) != c)
c = old;
- return c != u;
+ return c;
}
-#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
+#endif /* __LINUX_ARM_ARCH__ */
+
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
#define atomic_inc(v) atomic_add(1, v)
#define atomic_dec(v) atomic_sub(1, v)
@@ -230,11 +241,265 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u)
#define atomic_add_negative(i,v) (atomic_add_return(i, v) < 0)
-#define smp_mb__before_atomic_dec() smp_mb()
-#define smp_mb__after_atomic_dec() smp_mb()
-#define smp_mb__before_atomic_inc() smp_mb()
-#define smp_mb__after_atomic_inc() smp_mb()
+#ifndef CONFIG_GENERIC_ATOMIC64
+typedef struct {
+ long long counter;
+} atomic64_t;
+
+#define ATOMIC64_INIT(i) { (i) }
+
+#ifdef CONFIG_ARM_LPAE
+static inline long long atomic64_read(const atomic64_t *v)
+{
+ long long result;
+
+ __asm__ __volatile__("@ atomic64_read\n"
+" ldrd %0, %H0, [%1]"
+ : "=&r" (result)
+ : "r" (&v->counter), "Qo" (v->counter)
+ );
+
+ return result;
+}
+
+static inline void atomic64_set(atomic64_t *v, long long i)
+{
+ __asm__ __volatile__("@ atomic64_set\n"
+" strd %2, %H2, [%1]"
+ : "=Qo" (v->counter)
+ : "r" (&v->counter), "r" (i)
+ );
+}
+#else
+static inline long long atomic64_read(const atomic64_t *v)
+{
+ long long result;
+
+ __asm__ __volatile__("@ atomic64_read\n"
+" ldrexd %0, %H0, [%1]"
+ : "=&r" (result)
+ : "r" (&v->counter), "Qo" (v->counter)
+ );
+
+ return result;
+}
+
+static inline void atomic64_set(atomic64_t *v, long long i)
+{
+ long long tmp;
+
+ prefetchw(&v->counter);
+ __asm__ __volatile__("@ atomic64_set\n"
+"1: ldrexd %0, %H0, [%2]\n"
+" strexd %0, %3, %H3, [%2]\n"
+" teq %0, #0\n"
+" bne 1b"
+ : "=&r" (tmp), "=Qo" (v->counter)
+ : "r" (&v->counter), "r" (i)
+ : "cc");
+}
+#endif
+
+static inline void atomic64_add(long long i, atomic64_t *v)
+{
+ long long result;
+ unsigned long tmp;
+
+ prefetchw(&v->counter);
+ __asm__ __volatile__("@ atomic64_add\n"
+"1: ldrexd %0, %H0, [%3]\n"
+" adds %Q0, %Q0, %Q4\n"
+" adc %R0, %R0, %R4\n"
+" strexd %1, %0, %H0, [%3]\n"
+" teq %1, #0\n"
+" bne 1b"
+ : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter)
+ : "r" (&v->counter), "r" (i)
+ : "cc");
+}
+
+static inline long long atomic64_add_return(long long i, atomic64_t *v)
+{
+ long long result;
+ unsigned long tmp;
+
+ smp_mb();
+ prefetchw(&v->counter);
+
+ __asm__ __volatile__("@ atomic64_add_return\n"
+"1: ldrexd %0, %H0, [%3]\n"
+" adds %Q0, %Q0, %Q4\n"
+" adc %R0, %R0, %R4\n"
+" strexd %1, %0, %H0, [%3]\n"
+" teq %1, #0\n"
+" bne 1b"
+ : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter)
+ : "r" (&v->counter), "r" (i)
+ : "cc");
+
+ smp_mb();
+
+ return result;
+}
+
+static inline void atomic64_sub(long long i, atomic64_t *v)
+{
+ long long result;
+ unsigned long tmp;
+
+ prefetchw(&v->counter);
+ __asm__ __volatile__("@ atomic64_sub\n"
+"1: ldrexd %0, %H0, [%3]\n"
+" subs %Q0, %Q0, %Q4\n"
+" sbc %R0, %R0, %R4\n"
+" strexd %1, %0, %H0, [%3]\n"
+" teq %1, #0\n"
+" bne 1b"
+ : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter)
+ : "r" (&v->counter), "r" (i)
+ : "cc");
+}
+
+static inline long long atomic64_sub_return(long long i, atomic64_t *v)
+{
+ long long result;
+ unsigned long tmp;
+
+ smp_mb();
+ prefetchw(&v->counter);
+
+ __asm__ __volatile__("@ atomic64_sub_return\n"
+"1: ldrexd %0, %H0, [%3]\n"
+" subs %Q0, %Q0, %Q4\n"
+" sbc %R0, %R0, %R4\n"
+" strexd %1, %0, %H0, [%3]\n"
+" teq %1, #0\n"
+" bne 1b"
+ : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter)
+ : "r" (&v->counter), "r" (i)
+ : "cc");
+
+ smp_mb();
+
+ return result;
+}
+
+static inline long long atomic64_cmpxchg(atomic64_t *ptr, long long old,
+ long long new)
+{
+ long long oldval;
+ unsigned long res;
+
+ smp_mb();
+ prefetchw(&ptr->counter);
+
+ do {
+ __asm__ __volatile__("@ atomic64_cmpxchg\n"
+ "ldrexd %1, %H1, [%3]\n"
+ "mov %0, #0\n"
+ "teq %1, %4\n"
+ "teqeq %H1, %H4\n"
+ "strexdeq %0, %5, %H5, [%3]"
+ : "=&r" (res), "=&r" (oldval), "+Qo" (ptr->counter)
+ : "r" (&ptr->counter), "r" (old), "r" (new)
+ : "cc");
+ } while (res);
+
+ smp_mb();
+
+ return oldval;
+}
+
+static inline long long atomic64_xchg(atomic64_t *ptr, long long new)
+{
+ long long result;
+ unsigned long tmp;
+
+ smp_mb();
+ prefetchw(&ptr->counter);
+
+ __asm__ __volatile__("@ atomic64_xchg\n"
+"1: ldrexd %0, %H0, [%3]\n"
+" strexd %1, %4, %H4, [%3]\n"
+" teq %1, #0\n"
+" bne 1b"
+ : "=&r" (result), "=&r" (tmp), "+Qo" (ptr->counter)
+ : "r" (&ptr->counter), "r" (new)
+ : "cc");
+
+ smp_mb();
+
+ return result;
+}
+
+static inline long long atomic64_dec_if_positive(atomic64_t *v)
+{
+ long long result;
+ unsigned long tmp;
+
+ smp_mb();
+ prefetchw(&v->counter);
+
+ __asm__ __volatile__("@ atomic64_dec_if_positive\n"
+"1: ldrexd %0, %H0, [%3]\n"
+" subs %Q0, %Q0, #1\n"
+" sbc %R0, %R0, #0\n"
+" teq %R0, #0\n"
+" bmi 2f\n"
+" strexd %1, %0, %H0, [%3]\n"
+" teq %1, #0\n"
+" bne 1b\n"
+"2:"
+ : "=&r" (result), "=&r" (tmp), "+Qo" (v->counter)
+ : "r" (&v->counter)
+ : "cc");
+
+ smp_mb();
+
+ return result;
+}
+
+static inline int atomic64_add_unless(atomic64_t *v, long long a, long long u)
+{
+ long long val;
+ unsigned long tmp;
+ int ret = 1;
+
+ smp_mb();
+ prefetchw(&v->counter);
+
+ __asm__ __volatile__("@ atomic64_add_unless\n"
+"1: ldrexd %0, %H0, [%4]\n"
+" teq %0, %5\n"
+" teqeq %H0, %H5\n"
+" moveq %1, #0\n"
+" beq 2f\n"
+" adds %Q0, %Q0, %Q6\n"
+" adc %R0, %R0, %R6\n"
+" strexd %2, %0, %H0, [%4]\n"
+" teq %2, #0\n"
+" bne 1b\n"
+"2:"
+ : "=&r" (val), "+r" (ret), "=&r" (tmp), "+Qo" (v->counter)
+ : "r" (&v->counter), "r" (u), "r" (a)
+ : "cc");
+
+ if (ret)
+ smp_mb();
+
+ return ret;
+}
-#include <asm-generic/atomic-long.h>
+#define atomic64_add_negative(a, v) (atomic64_add_return((a), (v)) < 0)
+#define atomic64_inc(v) atomic64_add(1LL, (v))
+#define atomic64_inc_return(v) atomic64_add_return(1LL, (v))
+#define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
+#define atomic64_sub_and_test(a, v) (atomic64_sub_return((a), (v)) == 0)
+#define atomic64_dec(v) atomic64_sub(1LL, (v))
+#define atomic64_dec_return(v) atomic64_sub_return(1LL, (v))
+#define atomic64_dec_and_test(v) (atomic64_dec_return((v)) == 0)
+#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1LL, 0LL)
+
+#endif /* !CONFIG_GENERIC_ATOMIC64 */
#endif
#endif
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-10 00:03:30 +0000