aboutsummaryrefslogtreecommitdiff
path: root/arch/mips/include/asm/local.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/mips/include/asm/local.h')
-rw-r--r--arch/mips/include/asm/local.h221
1 files changed, 221 insertions, 0 deletions
diff --git a/arch/mips/include/asm/local.h b/arch/mips/include/asm/local.h
new file mode 100644
index 00000000000..f96fd59e084
--- /dev/null
+++ b/arch/mips/include/asm/local.h
@@ -0,0 +1,221 @@
+#ifndef _ARCH_MIPS_LOCAL_H
+#define _ARCH_MIPS_LOCAL_H
+
+#include <linux/percpu.h>
+#include <linux/bitops.h>
+#include <asm/atomic.h>
+#include <asm/cmpxchg.h>
+#include <asm/war.h>
+
+typedef struct
+{
+ atomic_long_t a;
+} local_t;
+
+#define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) }
+
+#define local_read(l) atomic_long_read(&(l)->a)
+#define local_set(l, i) atomic_long_set(&(l)->a, (i))
+
+#define local_add(i, l) atomic_long_add((i), (&(l)->a))
+#define local_sub(i, l) atomic_long_sub((i), (&(l)->a))
+#define local_inc(l) atomic_long_inc(&(l)->a)
+#define local_dec(l) atomic_long_dec(&(l)->a)
+
+/*
+ * Same as above, but return the result value
+ */
+static __inline__ long local_add_return(long i, local_t * l)
+{
+ unsigned long result;
+
+ if (cpu_has_llsc && R10000_LLSC_WAR) {
+ unsigned long temp;
+
+ __asm__ __volatile__(
+ " .set mips3 \n"
+ "1:" __LL "%1, %2 # local_add_return \n"
+ " addu %0, %1, %3 \n"
+ __SC "%0, %2 \n"
+ " beqzl %0, 1b \n"
+ " addu %0, %1, %3 \n"
+ " .set mips0 \n"
+ : "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
+ : "Ir" (i), "m" (l->a.counter)
+ : "memory");
+ } else if (cpu_has_llsc) {
+ unsigned long temp;
+
+ __asm__ __volatile__(
+ " .set mips3 \n"
+ "1:" __LL "%1, %2 # local_add_return \n"
+ " addu %0, %1, %3 \n"
+ __SC "%0, %2 \n"
+ " beqz %0, 1b \n"
+ " addu %0, %1, %3 \n"
+ " .set mips0 \n"
+ : "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
+ : "Ir" (i), "m" (l->a.counter)
+ : "memory");
+ } else {
+ unsigned long flags;
+
+ local_irq_save(flags);
+ result = l->a.counter;
+ result += i;
+ l->a.counter = result;
+ local_irq_restore(flags);
+ }
+
+ return result;
+}
+
+static __inline__ long local_sub_return(long i, local_t * l)
+{
+ unsigned long result;
+
+ if (cpu_has_llsc && R10000_LLSC_WAR) {
+ unsigned long temp;
+
+ __asm__ __volatile__(
+ " .set mips3 \n"
+ "1:" __LL "%1, %2 # local_sub_return \n"
+ " subu %0, %1, %3 \n"
+ __SC "%0, %2 \n"
+ " beqzl %0, 1b \n"
+ " subu %0, %1, %3 \n"
+ " .set mips0 \n"
+ : "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
+ : "Ir" (i), "m" (l->a.counter)
+ : "memory");
+ } else if (cpu_has_llsc) {
+ unsigned long temp;
+
+ __asm__ __volatile__(
+ " .set mips3 \n"
+ "1:" __LL "%1, %2 # local_sub_return \n"
+ " subu %0, %1, %3 \n"
+ __SC "%0, %2 \n"
+ " beqz %0, 1b \n"
+ " subu %0, %1, %3 \n"
+ " .set mips0 \n"
+ : "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
+ : "Ir" (i), "m" (l->a.counter)
+ : "memory");
+ } else {
+ unsigned long flags;
+
+ local_irq_save(flags);
+ result = l->a.counter;
+ result -= i;
+ l->a.counter = result;
+ local_irq_restore(flags);
+ }
+
+ return result;
+}
+
+#define local_cmpxchg(l, o, n) \
+ ((long)cmpxchg_local(&((l)->a.counter), (o), (n)))
+#define local_xchg(l, n) (xchg_local(&((l)->a.counter), (n)))
+
+/**
+ * local_add_unless - add unless the number is a given value
+ * @l: pointer of type local_t
+ * @a: the amount to add to l...
+ * @u: ...unless l is equal to u.
+ *
+ * Atomically adds @a to @l, so long as it was not @u.
+ * Returns non-zero if @l was not @u, and zero otherwise.
+ */
+#define local_add_unless(l, a, u) \
+({ \
+ long c, old; \
+ c = local_read(l); \
+ while (c != (u) && (old = local_cmpxchg((l), c, c + (a))) != c) \
+ c = old; \
+ c != (u); \
+})
+#define local_inc_not_zero(l) local_add_unless((l), 1, 0)
+
+#define local_dec_return(l) local_sub_return(1, (l))
+#define local_inc_return(l) local_add_return(1, (l))
+
+/*
+ * local_sub_and_test - subtract value from variable and test result
+ * @i: integer value to subtract
+ * @l: pointer of type local_t
+ *
+ * Atomically subtracts @i from @l and returns
+ * true if the result is zero, or false for all
+ * other cases.
+ */
+#define local_sub_and_test(i, l) (local_sub_return((i), (l)) == 0)
+
+/*
+ * local_inc_and_test - increment and test
+ * @l: pointer of type local_t
+ *
+ * Atomically increments @l by 1
+ * and returns true if the result is zero, or false for all
+ * other cases.
+ */
+#define local_inc_and_test(l) (local_inc_return(l) == 0)
+
+/*
+ * local_dec_and_test - decrement by 1 and test
+ * @l: pointer of type local_t
+ *
+ * Atomically decrements @l by 1 and
+ * returns true if the result is 0, or false for all other
+ * cases.
+ */
+#define local_dec_and_test(l) (local_sub_return(1, (l)) == 0)
+
+/*
+ * local_add_negative - add and test if negative
+ * @l: pointer of type local_t
+ * @i: integer value to add
+ *
+ * Atomically adds @i to @l and returns true
+ * if the result is negative, or false when
+ * result is greater than or equal to zero.
+ */
+#define local_add_negative(i, l) (local_add_return(i, (l)) < 0)
+
+/* Use these for per-cpu local_t variables: on some archs they are
+ * much more efficient than these naive implementations. Note they take
+ * a variable, not an address.
+ */
+
+#define __local_inc(l) ((l)->a.counter++)
+#define __local_dec(l) ((l)->a.counter++)
+#define __local_add(i, l) ((l)->a.counter+=(i))
+#define __local_sub(i, l) ((l)->a.counter-=(i))
+
+/* Need to disable preemption for the cpu local counters otherwise we could
+ still access a variable of a previous CPU in a non atomic way. */
+#define cpu_local_wrap_v(l) \
+ ({ local_t res__; \
+ preempt_disable(); \
+ res__ = (l); \
+ preempt_enable(); \
+ res__; })
+#define cpu_local_wrap(l) \
+ ({ preempt_disable(); \
+ l; \
+ preempt_enable(); }) \
+
+#define cpu_local_read(l) cpu_local_wrap_v(local_read(&__get_cpu_var(l)))
+#define cpu_local_set(l, i) cpu_local_wrap(local_set(&__get_cpu_var(l), (i)))
+#define cpu_local_inc(l) cpu_local_wrap(local_inc(&__get_cpu_var(l)))
+#define cpu_local_dec(l) cpu_local_wrap(local_dec(&__get_cpu_var(l)))
+#define cpu_local_add(i, l) cpu_local_wrap(local_add((i), &__get_cpu_var(l)))
+#define cpu_local_sub(i, l) cpu_local_wrap(local_sub((i), &__get_cpu_var(l)))
+
+#define __cpu_local_inc(l) cpu_local_inc(l)
+#define __cpu_local_dec(l) cpu_local_dec(l)
+#define __cpu_local_add(i, l) cpu_local_add((i), (l))
+#define __cpu_local_sub(i, l) cpu_local_sub((i), (l))
+
+#endif /* _ARCH_MIPS_LOCAL_H */