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Re: [Ltt-dev] [PATCH 5/10] local_t : MIPS
- From: Mathieu Desnoyers <compudj at krystal dot dyndns dot org>
- To: linux-kernel at vger dot kernel dot org, Andrew Morton <akpm at osdl dot org>, Ingo Molnar <mingo at redhat dot com>, Greg Kroah-Hartman <gregkh at suse dot de>, Christoph Hellwig <hch at infradead dot org>, Linux-MIPS <linux-mips at linux-mips dot org>
- Cc: Douglas Niehaus <niehaus at eecs dot ku dot edu>, "Martin J. Bligh" <mbligh at mbligh dot org>, ltt-dev at shafik dot org, Thomas Gleixner <tglx at linutronix dot de>, systemtap at sources dot redhat dot com
- Date: Thu, 21 Dec 2006 09:04:11 -0500
- Subject: Re: [Ltt-dev] [PATCH 5/10] local_t : MIPS
- References: <20061221001545.GP28643@Krystal> <20061221002508.GU28643@Krystal>
Sorry, I meant MIPS.
* Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca) wrote:
> ia64 architecture local_t extension.
>
> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
>
> --- a/include/asm-mips/system.h
> +++ b/include/asm-mips/system.h
> @@ -253,6 +253,58 @@ static inline unsigned long __cmpxchg_u3
> return retval;
> }
>
> +static inline unsigned long __cmpxchg_u32_local(volatile int * m,
> + unsigned long old, unsigned long new)
> +{
> + __u32 retval;
> +
> + if (cpu_has_llsc && R10000_LLSC_WAR) {
> + __asm__ __volatile__(
> + " .set push \n"
> + " .set noat \n"
> + " .set mips3 \n"
> + "1: ll %0, %2 # __cmpxchg_u32 \n"
> + " bne %0, %z3, 2f \n"
> + " .set mips0 \n"
> + " move $1, %z4 \n"
> + " .set mips3 \n"
> + " sc $1, %1 \n"
> + " beqzl $1, 1b \n"
> + "2: \n"
> + " .set pop \n"
> + : "=&r" (retval), "=R" (*m)
> + : "R" (*m), "Jr" (old), "Jr" (new)
> + : "memory");
> + } else if (cpu_has_llsc) {
> + __asm__ __volatile__(
> + " .set push \n"
> + " .set noat \n"
> + " .set mips3 \n"
> + "1: ll %0, %2 # __cmpxchg_u32 \n"
> + " bne %0, %z3, 2f \n"
> + " .set mips0 \n"
> + " move $1, %z4 \n"
> + " .set mips3 \n"
> + " sc $1, %1 \n"
> + " beqz $1, 1b \n"
> + "2: \n"
> + " .set pop \n"
> + : "=&r" (retval), "=R" (*m)
> + : "R" (*m), "Jr" (old), "Jr" (new)
> + : "memory");
> + } else {
> + unsigned long flags;
> +
> + local_irq_save(flags);
> + retval = *m;
> + if (retval == old)
> + *m = new;
> + local_irq_restore(flags); /* implies memory barrier */
> + }
> +
> + return retval;
> +}
> +
> #ifdef CONFIG_64BIT
> static inline unsigned long __cmpxchg_u64(volatile int * m, unsigned long old,
> unsigned long new)
> @@ -303,10 +355,62 @@ static inline unsigned long __cmpxchg_u6
>
> return retval;
> }
> +
> +static inline unsigned long __cmpxchg_u64_local(volatile int * m,
> + unsigned long old, unsigned long new)
> +{
> + __u64 retval;
> +
> + if (cpu_has_llsc && R10000_LLSC_WAR) {
> + __asm__ __volatile__(
> + " .set push \n"
> + " .set noat \n"
> + " .set mips3 \n"
> + "1: lld %0, %2 # __cmpxchg_u64 \n"
> + " bne %0, %z3, 2f \n"
> + " move $1, %z4 \n"
> + " scd $1, %1 \n"
> + " beqzl $1, 1b \n"
> + "2: \n"
> + " .set pop \n"
> + : "=&r" (retval), "=R" (*m)
> + : "R" (*m), "Jr" (old), "Jr" (new)
> + : "memory");
> + } else if (cpu_has_llsc) {
> + __asm__ __volatile__(
> + " .set push \n"
> + " .set noat \n"
> + " .set mips3 \n"
> + "1: lld %0, %2 # __cmpxchg_u64 \n"
> + " bne %0, %z3, 2f \n"
> + " move $1, %z4 \n"
> + " scd $1, %1 \n"
> + " beqz $1, 1b \n"
> + "2: \n"
> + " .set pop \n"
> + : "=&r" (retval), "=R" (*m)
> + : "R" (*m), "Jr" (old), "Jr" (new)
> + : "memory");
> + } else {
> + unsigned long flags;
> +
> + local_irq_save(flags);
> + retval = *m;
> + if (retval == old)
> + *m = new;
> + local_irq_restore(flags); /* implies memory barrier */
> + }
> +
> + return retval;
> +}
> +
> #else
> extern unsigned long __cmpxchg_u64_unsupported_on_32bit_kernels(
> volatile int * m, unsigned long old, unsigned long new);
> #define __cmpxchg_u64 __cmpxchg_u64_unsupported_on_32bit_kernels
> +extern unsigned long __cmpxchg_u64_local_unsupported_on_32bit_kernels(
> + volatile int * m, unsigned long old, unsigned long new);
> +#define __cmpxchg_u64_local __cmpxchg_u64_local_unsupported_on_32bit_kernels
> #endif
>
> /* This function doesn't exist, so you'll get a linker error
> @@ -326,7 +430,26 @@ static inline unsigned long __cmpxchg(vo
> return old;
> }
>
> -#define cmpxchg(ptr,old,new) ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(old), (unsigned long)(new),sizeof(*(ptr))))
> +static inline unsigned long __cmpxchg_local(volatile void * ptr,
> + unsigned long old, unsigned long new, int size)
> +{
> + switch (size) {
> + case 4:
> + return __cmpxchg_u32_local(ptr, old, new);
> + case 8:
> + return __cmpxchg_u64_local(ptr, old, new);
> + }
> + __cmpxchg_called_with_bad_pointer();
> + return old;
> +}
> +
> +#define cmpxchg(ptr,old,new) \
> + ((__typeof__(*(ptr)))__cmpxchg((ptr), \
> + (unsigned long)(old), (unsigned long)(new),sizeof(*(ptr))))
> +
> +#define cmpxchg_local(ptr,old,new) \
> + ((__typeof__(*(ptr)))__cmpxchg_local((ptr), \
> + (unsigned long)(old), (unsigned long)(new),sizeof(*(ptr))))
>
> extern void set_handler (unsigned long offset, void *addr, unsigned long len);
> extern void set_uncached_handler (unsigned long offset, void *addr, unsigned long len);
> --- a/include/asm-mips/local.h
> +++ b/include/asm-mips/local.h
> @@ -1,60 +1,527 @@
> -#ifndef _ASM_LOCAL_H
> -#define _ASM_LOCAL_H
> +#ifndef _ARCH_POWERPC_LOCAL_H
> +#define _ARCH_POWERPC_LOCAL_H
>
> #include <linux/percpu.h>
> #include <asm/atomic.h>
>
> -#ifdef CONFIG_32BIT
> +typedef struct
> +{
> + local_long_t a;
> +} local_t;
>
> -typedef atomic_t local_t;
> +#define LOCAL_INIT(i) { local_LONG_INIT(i) }
>
> -#define LOCAL_INIT(i) ATOMIC_INIT(i)
> -#define local_read(v) atomic_read(v)
> -#define local_set(v,i) atomic_set(v,i)
> +#define local_read(l) local_long_read(&(l)->a)
> +#define local_set(l,i) local_long_set(&(l)->a, (i))
>
> -#define local_inc(v) atomic_inc(v)
> -#define local_dec(v) atomic_dec(v)
> -#define local_add(i, v) atomic_add(i, v)
> -#define local_sub(i, v) atomic_sub(i, v)
> +#define local_add(i,l) local_long_add((i),(&(l)->a))
> +#define local_sub(i,l) local_long_sub((i),(&(l)->a))
> +#define local_inc(l) local_long_inc(&(l)->a)
> +#define local_dec(l) local_long_dec(&(l)->a)
>
> -#endif
>
> -#ifdef CONFIG_64BIT
> +#ifndef CONFIG_64BITS
>
> -typedef atomic64_t local_t;
> +/*
> + * Same as above, but return the result value
> + */
> +static __inline__ int local_add_return(int 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__ int local_sub_return(int 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;
> +}
> +
> +/*
> + * local_sub_if_positive - conditionally subtract integer from atomic variable
> + * @i: integer value to subtract
> + * @l: pointer of type local_t
> + *
> + * Atomically test @l and subtract @i if @l is greater or equal than @i.
> + * The function returns the old value of @l minus @i.
> + */
> +static __inline__ int local_sub_if_positive(int 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_if_positive\n"
> + " subu %0, %1, %3 \n"
> + " bltz %0, 1f \n"
> + " sc %0, %2 \n"
> + " .set noreorder \n"
> + " beqzl %0, 1b \n"
> + " subu %0, %1, %3 \n"
> + " .set reorder \n"
> + "1: \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_if_positive\n"
> + " subu %0, %1, %3 \n"
> + " bltz %0, 1f \n"
> + " sc %0, %2 \n"
> + " .set noreorder \n"
> + " beqz %0, 1b \n"
> + " subu %0, %1, %3 \n"
> + " .set reorder \n"
> + "1: \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;
> + if (result >= 0)
> + &(l->a.counter) = result;
> + local_irq_restore(flags);
> + }
> +
> + return result;
> +}
> +
> +#define local_cmpxchg(l, o, n) \
> + ((long)cmpxchg(&((l)->a.counter), (o), (n)))
> +#define local_xchg(l, new) (xchg(&((l)->a.counter), new))
> +
> +/**
> + * 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_dec_if_positive - decrement by 1 if old value positive
> + * @l: pointer of type local_t
> + */
> +#define local_dec_if_positive(l) local_sub_if_positive(1, l)
> +
> +/*
> + * 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)
> +
> +#else /* CONFIG_64BITS */
>
> -#define LOCAL_INIT(i) ATOMIC64_INIT(i)
> -#define local_read(v) atomic64_read(v)
> -#define local_set(v,i) atomic64_set(v,i)
> +/*
> + * 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: lld %1, %2 # local_add_return \n"
> + " addu %0, %1, %3 \n"
> + " scd %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: lld %1, %2 # local_add_return \n"
> + " addu %0, %1, %3 \n"
> + " scd %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);
> + }
>
> -#define local_inc(v) atomic64_inc(v)
> -#define local_dec(v) atomic64_dec(v)
> -#define local_add(i, v) atomic64_add(i, v)
> -#define local_sub(i, v) atomic64_sub(i, v)
> + return result;
> +}
>
> -#endif
> +static __inline__ long local_sub_return(long i, local_t * l)
> +{
> + unsigned long result;
>
> -#define __local_inc(v) ((v)->counter++)
> -#define __local_dec(v) ((v)->counter--)
> -#define __local_add(i,v) ((v)->counter+=(i))
> -#define __local_sub(i,v) ((v)->counter-=(i))
> + if (cpu_has_llsc && R10000_LLSC_WAR) {
> + unsigned long temp;
> +
> + __asm__ __volatile__(
> + " .set mips3 \n"
> + "1: lld %1, %2 # local_sub_return \n"
> + " subu %0, %1, %3 \n"
> + " scd %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: lld %1, %2 # local_sub_return \n"
> + " subu %0, %1, %3 \n"
> + " scd %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;
> +}
>
> /*
> - * Use these for per-cpu local_t variables: on some archs they are
> + * local_sub_if_positive - conditionally subtract integer from atomic variable
> + * @i: integer value to subtract
> + * @l: pointer of type local_t
> + *
> + * Atomically test @l and subtract @i if @l is greater or equal than @i.
> + * The function returns the old value of @l minus @i.
> + */
> +static __inline__ long local_sub_if_positive(long i, local_t * l)
> +{
> + unsigned long result;
> +
> + if (cpu_has_llsc && R10000_LLSC_WAR) {
> + unsigned long temp;
> +
> + __asm__ __volatile__(
> + " .set mips3 \n"
> + "1: lld %1, %2 # local_sub_if_positive\n"
> + " dsubu %0, %1, %3 \n"
> + " bltz %0, 1f \n"
> + " scd %0, %2 \n"
> + " .set noreorder \n"
> + " beqzl %0, 1b \n"
> + " dsubu %0, %1, %3 \n"
> + " .set reorder \n"
> + "1: \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: lld %1, %2 # local_sub_if_positive\n"
> + " dsubu %0, %1, %3 \n"
> + " bltz %0, 1f \n"
> + " scd %0, %2 \n"
> + " .set noreorder \n"
> + " beqz %0, 1b \n"
> + " dsubu %0, %1, %3 \n"
> + " .set reorder \n"
> + "1: \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;
> + if (result >= 0)
> + &(l->a.counter) = result;
> + local_irq_restore(flags);
> + }
> +
> + return result;
> +}
> +
> +
> +#define local_cmpxchg(l, o, n) \
> + ((long)cmpxchg(&((l)->a.counter), (o), (n)))
> +#define local_xchg(l, new) (xchg(&((l)->a.counter), new))
> +
> +/**
> + * 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_dec_if_positive - decrement by 1 if old value positive
> + * @l: pointer of type local_t
> + */
> +#define local_dec_if_positive(l) local_sub_if_positive(1, l)
> +
> +/*
> + * 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)
> +
> +#endif /* !CONFIG_64BITS */
> +
> +
> +/* 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.
> + *
> + * This could be done better if we moved the per cpu data directly
> + * after GS.
> */
> -#define cpu_local_read(v) local_read(&__get_cpu_var(v))
> -#define cpu_local_set(v, i) local_set(&__get_cpu_var(v), (i))
>
> -#define cpu_local_inc(v) local_inc(&__get_cpu_var(v))
> -#define cpu_local_dec(v) local_dec(&__get_cpu_var(v))
> -#define cpu_local_add(i, v) local_add((i), &__get_cpu_var(v))
> -#define cpu_local_sub(i, v) local_sub((i), &__get_cpu_var(v))
> +#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(v) __local_inc(&__get_cpu_var(v))
> -#define __cpu_local_dec(v) __local_dec(&__get_cpu_var(v))
> -#define __cpu_local_add(i, v) __local_add((i), &__get_cpu_var(v))
> -#define __cpu_local_sub(i, v) __local_sub((i), &__get_cpu_var(v))
> +#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 /* _ASM_LOCAL_H */
> +#endif /* _ARCH_POWERPC_LOCAL_H */
>
--
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