forked from Minki/linux
7837314d14
It was a nice optimization - on paper at least. In practice it results in
branches that may exceed the maximum legal range for a branch. We can
fight that problem with -ffunction-sections but -ffunction-sections again
is incompatible with -pg used by the function tracer.
By rewriting the loop around all simple LL/SC blocks to C we reduce the
amount of inline assembler and at the same time allow GCC to often fill
the branch delay slots with something sensible or whatever else clever
optimization it may have up in its sleeve.
With this optimization gone we also no longer need -ffunction-sections,
so drop it.
This optimization was originally introduced in 2.6.21, commit
5999eca25c1fd4b9b9aca7833b04d10fe4bc877d (linux-mips.org) rsp.
f65e4fa8e0 (kernel.org).
Original fix for the issues which caused me to pull this optimization by
Paul Gortmaker <paul.gortmaker@windriver.com>.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
787 lines
18 KiB
C
787 lines
18 KiB
C
/*
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* Atomic operations that C can't guarantee us. Useful for
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* resource counting etc..
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*
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* But use these as seldom as possible since they are much more slower
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* than regular operations.
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*
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* Copyright (C) 1996, 97, 99, 2000, 03, 04, 06 by Ralf Baechle
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*/
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#ifndef _ASM_ATOMIC_H
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#define _ASM_ATOMIC_H
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#include <linux/irqflags.h>
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#include <linux/types.h>
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#include <asm/barrier.h>
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#include <asm/cpu-features.h>
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#include <asm/war.h>
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#include <asm/system.h>
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#define ATOMIC_INIT(i) { (i) }
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/*
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* atomic_read - read atomic variable
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* @v: pointer of type atomic_t
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*
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* Atomically reads the value of @v.
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*/
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#define atomic_read(v) (*(volatile int *)&(v)->counter)
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/*
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* atomic_set - set atomic variable
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* @v: pointer of type atomic_t
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* @i: required value
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*
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* Atomically sets the value of @v to @i.
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*/
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#define atomic_set(v, i) ((v)->counter = (i))
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/*
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* atomic_add - add integer to atomic variable
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* @i: integer value to add
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* @v: pointer of type atomic_t
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*
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* Atomically adds @i to @v.
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*/
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static __inline__ void atomic_add(int i, atomic_t * v)
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{
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if (kernel_uses_llsc && R10000_LLSC_WAR) {
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int temp;
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__asm__ __volatile__(
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" .set mips3 \n"
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"1: ll %0, %1 # atomic_add \n"
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" addu %0, %2 \n"
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" sc %0, %1 \n"
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" beqzl %0, 1b \n"
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" .set mips0 \n"
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: "=&r" (temp), "=m" (v->counter)
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: "Ir" (i), "m" (v->counter));
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} else if (kernel_uses_llsc) {
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int temp;
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do {
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__asm__ __volatile__(
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" .set mips3 \n"
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" ll %0, %1 # atomic_add \n"
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" addu %0, %2 \n"
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" sc %0, %1 \n"
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" .set mips0 \n"
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: "=&r" (temp), "=m" (v->counter)
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: "Ir" (i), "m" (v->counter));
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} while (unlikely(!temp));
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} else {
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unsigned long flags;
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raw_local_irq_save(flags);
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v->counter += i;
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raw_local_irq_restore(flags);
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}
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}
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/*
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* atomic_sub - subtract the atomic variable
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* @i: integer value to subtract
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* @v: pointer of type atomic_t
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*
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* Atomically subtracts @i from @v.
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*/
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static __inline__ void atomic_sub(int i, atomic_t * v)
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{
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if (kernel_uses_llsc && R10000_LLSC_WAR) {
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int temp;
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__asm__ __volatile__(
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" .set mips3 \n"
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"1: ll %0, %1 # atomic_sub \n"
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" subu %0, %2 \n"
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" sc %0, %1 \n"
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" beqzl %0, 1b \n"
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" .set mips0 \n"
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: "=&r" (temp), "=m" (v->counter)
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: "Ir" (i), "m" (v->counter));
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} else if (kernel_uses_llsc) {
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int temp;
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do {
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__asm__ __volatile__(
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" .set mips3 \n"
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" ll %0, %1 # atomic_sub \n"
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" subu %0, %2 \n"
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" sc %0, %1 \n"
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" .set mips0 \n"
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: "=&r" (temp), "=m" (v->counter)
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: "Ir" (i), "m" (v->counter));
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} while (unlikely(!temp));
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} else {
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unsigned long flags;
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raw_local_irq_save(flags);
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v->counter -= i;
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raw_local_irq_restore(flags);
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}
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}
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/*
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* Same as above, but return the result value
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*/
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static __inline__ int atomic_add_return(int i, atomic_t * v)
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{
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int result;
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smp_mb__before_llsc();
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if (kernel_uses_llsc && R10000_LLSC_WAR) {
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int temp;
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__asm__ __volatile__(
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" .set mips3 \n"
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"1: ll %1, %2 # atomic_add_return \n"
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" addu %0, %1, %3 \n"
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" sc %0, %2 \n"
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" beqzl %0, 1b \n"
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" addu %0, %1, %3 \n"
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" .set mips0 \n"
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: "=&r" (result), "=&r" (temp), "=m" (v->counter)
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: "Ir" (i), "m" (v->counter)
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: "memory");
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} else if (kernel_uses_llsc) {
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int temp;
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do {
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__asm__ __volatile__(
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" .set mips3 \n"
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" ll %1, %2 # atomic_add_return \n"
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" addu %0, %1, %3 \n"
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" sc %0, %2 \n"
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" .set mips0 \n"
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: "=&r" (result), "=&r" (temp), "=m" (v->counter)
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: "Ir" (i), "m" (v->counter)
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: "memory");
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} while (unlikely(!result));
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result = temp + i;
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} else {
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unsigned long flags;
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raw_local_irq_save(flags);
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result = v->counter;
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result += i;
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v->counter = result;
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raw_local_irq_restore(flags);
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}
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smp_llsc_mb();
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return result;
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}
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static __inline__ int atomic_sub_return(int i, atomic_t * v)
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{
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int result;
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smp_mb__before_llsc();
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if (kernel_uses_llsc && R10000_LLSC_WAR) {
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int temp;
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__asm__ __volatile__(
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" .set mips3 \n"
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"1: ll %1, %2 # atomic_sub_return \n"
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" subu %0, %1, %3 \n"
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" sc %0, %2 \n"
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" beqzl %0, 1b \n"
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" subu %0, %1, %3 \n"
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" .set mips0 \n"
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: "=&r" (result), "=&r" (temp), "=m" (v->counter)
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: "Ir" (i), "m" (v->counter)
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: "memory");
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result = temp - i;
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} else if (kernel_uses_llsc) {
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int temp;
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do {
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__asm__ __volatile__(
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" .set mips3 \n"
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" ll %1, %2 # atomic_sub_return \n"
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" subu %0, %1, %3 \n"
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" sc %0, %2 \n"
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" .set mips0 \n"
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: "=&r" (result), "=&r" (temp), "=m" (v->counter)
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: "Ir" (i), "m" (v->counter)
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: "memory");
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} while (unlikely(!result));
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result = temp - i;
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} else {
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unsigned long flags;
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raw_local_irq_save(flags);
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result = v->counter;
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result -= i;
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v->counter = result;
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raw_local_irq_restore(flags);
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}
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|
smp_llsc_mb();
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return result;
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}
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/*
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* atomic_sub_if_positive - conditionally subtract integer from atomic variable
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* @i: integer value to subtract
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* @v: pointer of type atomic_t
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*
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* Atomically test @v and subtract @i if @v is greater or equal than @i.
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* The function returns the old value of @v minus @i.
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*/
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static __inline__ int atomic_sub_if_positive(int i, atomic_t * v)
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{
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|
int result;
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|
smp_mb__before_llsc();
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|
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|
if (kernel_uses_llsc && R10000_LLSC_WAR) {
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int temp;
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|
__asm__ __volatile__(
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" .set mips3 \n"
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"1: ll %1, %2 # atomic_sub_if_positive\n"
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" subu %0, %1, %3 \n"
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" bltz %0, 1f \n"
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" sc %0, %2 \n"
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" .set noreorder \n"
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" beqzl %0, 1b \n"
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" subu %0, %1, %3 \n"
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" .set reorder \n"
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"1: \n"
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" .set mips0 \n"
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: "=&r" (result), "=&r" (temp), "=m" (v->counter)
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: "Ir" (i), "m" (v->counter)
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: "memory");
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} else if (kernel_uses_llsc) {
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int temp;
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__asm__ __volatile__(
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" .set mips3 \n"
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"1: ll %1, %2 # atomic_sub_if_positive\n"
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" subu %0, %1, %3 \n"
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" bltz %0, 1f \n"
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" sc %0, %2 \n"
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" .set noreorder \n"
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" beqz %0, 1b \n"
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" subu %0, %1, %3 \n"
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" .set reorder \n"
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"1: \n"
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" .set mips0 \n"
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: "=&r" (result), "=&r" (temp), "=m" (v->counter)
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: "Ir" (i), "m" (v->counter)
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: "memory");
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} else {
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unsigned long flags;
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raw_local_irq_save(flags);
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result = v->counter;
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result -= i;
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if (result >= 0)
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v->counter = result;
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raw_local_irq_restore(flags);
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}
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smp_llsc_mb();
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return result;
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}
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#define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
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#define atomic_xchg(v, new) (xchg(&((v)->counter), (new)))
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/**
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* atomic_add_unless - add unless the number is a given value
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* @v: pointer of type atomic_t
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* @a: the amount to add to v...
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* @u: ...unless v is equal to u.
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*
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* Atomically adds @a to @v, so long as it was not @u.
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* Returns non-zero if @v was not @u, and zero otherwise.
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*/
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static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
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{
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int c, old;
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c = atomic_read(v);
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for (;;) {
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if (unlikely(c == (u)))
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break;
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old = atomic_cmpxchg((v), c, c + (a));
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|
if (likely(old == c))
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break;
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c = old;
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|
}
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return c != (u);
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|
}
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#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
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#define atomic_dec_return(v) atomic_sub_return(1, (v))
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#define atomic_inc_return(v) atomic_add_return(1, (v))
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|
/*
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|
* atomic_sub_and_test - subtract value from variable and test result
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* @i: integer value to subtract
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* @v: pointer of type atomic_t
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*
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|
* Atomically subtracts @i from @v and returns
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* true if the result is zero, or false for all
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|
* other cases.
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*/
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#define atomic_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0)
|
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|
/*
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|
* atomic_inc_and_test - increment and test
|
|
* @v: pointer of type atomic_t
|
|
*
|
|
* Atomically increments @v by 1
|
|
* and returns true if the result is zero, or false for all
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|
* other cases.
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|
*/
|
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#define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
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|
|
|
/*
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|
* atomic_dec_and_test - decrement by 1 and test
|
|
* @v: pointer of type atomic_t
|
|
*
|
|
* Atomically decrements @v by 1 and
|
|
* returns true if the result is 0, or false for all other
|
|
* cases.
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|
*/
|
|
#define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
|
|
|
|
/*
|
|
* atomic_dec_if_positive - decrement by 1 if old value positive
|
|
* @v: pointer of type atomic_t
|
|
*/
|
|
#define atomic_dec_if_positive(v) atomic_sub_if_positive(1, v)
|
|
|
|
/*
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|
* atomic_inc - increment atomic variable
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|
* @v: pointer of type atomic_t
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|
*
|
|
* Atomically increments @v by 1.
|
|
*/
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|
#define atomic_inc(v) atomic_add(1, (v))
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|
|
|
/*
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|
* atomic_dec - decrement and test
|
|
* @v: pointer of type atomic_t
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|
*
|
|
* Atomically decrements @v by 1.
|
|
*/
|
|
#define atomic_dec(v) atomic_sub(1, (v))
|
|
|
|
/*
|
|
* atomic_add_negative - add and test if negative
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|
* @v: pointer of type atomic_t
|
|
* @i: integer value to add
|
|
*
|
|
* Atomically adds @i to @v and returns true
|
|
* if the result is negative, or false when
|
|
* result is greater than or equal to zero.
|
|
*/
|
|
#define atomic_add_negative(i, v) (atomic_add_return(i, (v)) < 0)
|
|
|
|
#ifdef CONFIG_64BIT
|
|
|
|
#define ATOMIC64_INIT(i) { (i) }
|
|
|
|
/*
|
|
* atomic64_read - read atomic variable
|
|
* @v: pointer of type atomic64_t
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|
*
|
|
*/
|
|
#define atomic64_read(v) (*(volatile long *)&(v)->counter)
|
|
|
|
/*
|
|
* atomic64_set - set atomic variable
|
|
* @v: pointer of type atomic64_t
|
|
* @i: required value
|
|
*/
|
|
#define atomic64_set(v, i) ((v)->counter = (i))
|
|
|
|
/*
|
|
* atomic64_add - add integer to atomic variable
|
|
* @i: integer value to add
|
|
* @v: pointer of type atomic64_t
|
|
*
|
|
* Atomically adds @i to @v.
|
|
*/
|
|
static __inline__ void atomic64_add(long i, atomic64_t * v)
|
|
{
|
|
if (kernel_uses_llsc && R10000_LLSC_WAR) {
|
|
long temp;
|
|
|
|
__asm__ __volatile__(
|
|
" .set mips3 \n"
|
|
"1: lld %0, %1 # atomic64_add \n"
|
|
" daddu %0, %2 \n"
|
|
" scd %0, %1 \n"
|
|
" beqzl %0, 1b \n"
|
|
" .set mips0 \n"
|
|
: "=&r" (temp), "=m" (v->counter)
|
|
: "Ir" (i), "m" (v->counter));
|
|
} else if (kernel_uses_llsc) {
|
|
long temp;
|
|
|
|
do {
|
|
__asm__ __volatile__(
|
|
" .set mips3 \n"
|
|
" lld %0, %1 # atomic64_add \n"
|
|
" daddu %0, %2 \n"
|
|
" scd %0, %1 \n"
|
|
" .set mips0 \n"
|
|
: "=&r" (temp), "=m" (v->counter)
|
|
: "Ir" (i), "m" (v->counter));
|
|
} while (unlikely(!temp));
|
|
} else {
|
|
unsigned long flags;
|
|
|
|
raw_local_irq_save(flags);
|
|
v->counter += i;
|
|
raw_local_irq_restore(flags);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* atomic64_sub - subtract the atomic variable
|
|
* @i: integer value to subtract
|
|
* @v: pointer of type atomic64_t
|
|
*
|
|
* Atomically subtracts @i from @v.
|
|
*/
|
|
static __inline__ void atomic64_sub(long i, atomic64_t * v)
|
|
{
|
|
if (kernel_uses_llsc && R10000_LLSC_WAR) {
|
|
long temp;
|
|
|
|
__asm__ __volatile__(
|
|
" .set mips3 \n"
|
|
"1: lld %0, %1 # atomic64_sub \n"
|
|
" dsubu %0, %2 \n"
|
|
" scd %0, %1 \n"
|
|
" beqzl %0, 1b \n"
|
|
" .set mips0 \n"
|
|
: "=&r" (temp), "=m" (v->counter)
|
|
: "Ir" (i), "m" (v->counter));
|
|
} else if (kernel_uses_llsc) {
|
|
long temp;
|
|
|
|
do {
|
|
__asm__ __volatile__(
|
|
" .set mips3 \n"
|
|
" lld %0, %1 # atomic64_sub \n"
|
|
" dsubu %0, %2 \n"
|
|
" scd %0, %1 \n"
|
|
" .set mips0 \n"
|
|
: "=&r" (temp), "=m" (v->counter)
|
|
: "Ir" (i), "m" (v->counter));
|
|
} while (unlikely(!temp));
|
|
} else {
|
|
unsigned long flags;
|
|
|
|
raw_local_irq_save(flags);
|
|
v->counter -= i;
|
|
raw_local_irq_restore(flags);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Same as above, but return the result value
|
|
*/
|
|
static __inline__ long atomic64_add_return(long i, atomic64_t * v)
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{
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long result;
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smp_mb__before_llsc();
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|
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if (kernel_uses_llsc && R10000_LLSC_WAR) {
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long temp;
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__asm__ __volatile__(
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" .set mips3 \n"
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"1: lld %1, %2 # atomic64_add_return \n"
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" daddu %0, %1, %3 \n"
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" scd %0, %2 \n"
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" beqzl %0, 1b \n"
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" daddu %0, %1, %3 \n"
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" .set mips0 \n"
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: "=&r" (result), "=&r" (temp), "=m" (v->counter)
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: "Ir" (i), "m" (v->counter)
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: "memory");
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} else if (kernel_uses_llsc) {
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long temp;
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|
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do {
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__asm__ __volatile__(
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" .set mips3 \n"
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" lld %1, %2 # atomic64_add_return \n"
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" daddu %0, %1, %3 \n"
|
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" scd %0, %2 \n"
|
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" .set mips0 \n"
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: "=&r" (result), "=&r" (temp), "=m" (v->counter)
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: "Ir" (i), "m" (v->counter)
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: "memory");
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} while (unlikely(!result));
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|
|
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result = temp + i;
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} else {
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unsigned long flags;
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|
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raw_local_irq_save(flags);
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result = v->counter;
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result += i;
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v->counter = result;
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raw_local_irq_restore(flags);
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}
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|
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smp_llsc_mb();
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|
|
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return result;
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}
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|
|
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static __inline__ long atomic64_sub_return(long i, atomic64_t * v)
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|
{
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|
long result;
|
|
|
|
smp_mb__before_llsc();
|
|
|
|
if (kernel_uses_llsc && R10000_LLSC_WAR) {
|
|
long temp;
|
|
|
|
__asm__ __volatile__(
|
|
" .set mips3 \n"
|
|
"1: lld %1, %2 # atomic64_sub_return \n"
|
|
" dsubu %0, %1, %3 \n"
|
|
" scd %0, %2 \n"
|
|
" beqzl %0, 1b \n"
|
|
" dsubu %0, %1, %3 \n"
|
|
" .set mips0 \n"
|
|
: "=&r" (result), "=&r" (temp), "=m" (v->counter)
|
|
: "Ir" (i), "m" (v->counter)
|
|
: "memory");
|
|
} else if (kernel_uses_llsc) {
|
|
long temp;
|
|
|
|
do {
|
|
__asm__ __volatile__(
|
|
" .set mips3 \n"
|
|
" lld %1, %2 # atomic64_sub_return \n"
|
|
" dsubu %0, %1, %3 \n"
|
|
" scd %0, %2 \n"
|
|
" .set mips0 \n"
|
|
: "=&r" (result), "=&r" (temp), "=m" (v->counter)
|
|
: "Ir" (i), "m" (v->counter)
|
|
: "memory");
|
|
} while (unlikely(!result));
|
|
|
|
result = temp - i;
|
|
} else {
|
|
unsigned long flags;
|
|
|
|
raw_local_irq_save(flags);
|
|
result = v->counter;
|
|
result -= i;
|
|
v->counter = result;
|
|
raw_local_irq_restore(flags);
|
|
}
|
|
|
|
smp_llsc_mb();
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* atomic64_sub_if_positive - conditionally subtract integer from atomic variable
|
|
* @i: integer value to subtract
|
|
* @v: pointer of type atomic64_t
|
|
*
|
|
* Atomically test @v and subtract @i if @v is greater or equal than @i.
|
|
* The function returns the old value of @v minus @i.
|
|
*/
|
|
static __inline__ long atomic64_sub_if_positive(long i, atomic64_t * v)
|
|
{
|
|
long result;
|
|
|
|
smp_mb__before_llsc();
|
|
|
|
if (kernel_uses_llsc && R10000_LLSC_WAR) {
|
|
long temp;
|
|
|
|
__asm__ __volatile__(
|
|
" .set mips3 \n"
|
|
"1: lld %1, %2 # atomic64_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" (v->counter)
|
|
: "Ir" (i), "m" (v->counter)
|
|
: "memory");
|
|
} else if (kernel_uses_llsc) {
|
|
long temp;
|
|
|
|
__asm__ __volatile__(
|
|
" .set mips3 \n"
|
|
"1: lld %1, %2 # atomic64_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" (v->counter)
|
|
: "Ir" (i), "m" (v->counter)
|
|
: "memory");
|
|
} else {
|
|
unsigned long flags;
|
|
|
|
raw_local_irq_save(flags);
|
|
result = v->counter;
|
|
result -= i;
|
|
if (result >= 0)
|
|
v->counter = result;
|
|
raw_local_irq_restore(flags);
|
|
}
|
|
|
|
smp_llsc_mb();
|
|
|
|
return result;
|
|
}
|
|
|
|
#define atomic64_cmpxchg(v, o, n) \
|
|
((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n)))
|
|
#define atomic64_xchg(v, new) (xchg(&((v)->counter), (new)))
|
|
|
|
/**
|
|
* atomic64_add_unless - add unless the number is a given value
|
|
* @v: pointer of type atomic64_t
|
|
* @a: the amount to add to v...
|
|
* @u: ...unless v is equal to u.
|
|
*
|
|
* Atomically adds @a to @v, so long as it was not @u.
|
|
* Returns non-zero if @v was not @u, and zero otherwise.
|
|
*/
|
|
static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u)
|
|
{
|
|
long c, old;
|
|
c = atomic64_read(v);
|
|
for (;;) {
|
|
if (unlikely(c == (u)))
|
|
break;
|
|
old = atomic64_cmpxchg((v), c, c + (a));
|
|
if (likely(old == c))
|
|
break;
|
|
c = old;
|
|
}
|
|
return c != (u);
|
|
}
|
|
|
|
#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
|
|
|
|
#define atomic64_dec_return(v) atomic64_sub_return(1, (v))
|
|
#define atomic64_inc_return(v) atomic64_add_return(1, (v))
|
|
|
|
/*
|
|
* atomic64_sub_and_test - subtract value from variable and test result
|
|
* @i: integer value to subtract
|
|
* @v: pointer of type atomic64_t
|
|
*
|
|
* Atomically subtracts @i from @v and returns
|
|
* true if the result is zero, or false for all
|
|
* other cases.
|
|
*/
|
|
#define atomic64_sub_and_test(i, v) (atomic64_sub_return((i), (v)) == 0)
|
|
|
|
/*
|
|
* atomic64_inc_and_test - increment and test
|
|
* @v: pointer of type atomic64_t
|
|
*
|
|
* Atomically increments @v by 1
|
|
* and returns true if the result is zero, or false for all
|
|
* other cases.
|
|
*/
|
|
#define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
|
|
|
|
/*
|
|
* atomic64_dec_and_test - decrement by 1 and test
|
|
* @v: pointer of type atomic64_t
|
|
*
|
|
* Atomically decrements @v by 1 and
|
|
* returns true if the result is 0, or false for all other
|
|
* cases.
|
|
*/
|
|
#define atomic64_dec_and_test(v) (atomic64_sub_return(1, (v)) == 0)
|
|
|
|
/*
|
|
* atomic64_dec_if_positive - decrement by 1 if old value positive
|
|
* @v: pointer of type atomic64_t
|
|
*/
|
|
#define atomic64_dec_if_positive(v) atomic64_sub_if_positive(1, v)
|
|
|
|
/*
|
|
* atomic64_inc - increment atomic variable
|
|
* @v: pointer of type atomic64_t
|
|
*
|
|
* Atomically increments @v by 1.
|
|
*/
|
|
#define atomic64_inc(v) atomic64_add(1, (v))
|
|
|
|
/*
|
|
* atomic64_dec - decrement and test
|
|
* @v: pointer of type atomic64_t
|
|
*
|
|
* Atomically decrements @v by 1.
|
|
*/
|
|
#define atomic64_dec(v) atomic64_sub(1, (v))
|
|
|
|
/*
|
|
* atomic64_add_negative - add and test if negative
|
|
* @v: pointer of type atomic64_t
|
|
* @i: integer value to add
|
|
*
|
|
* Atomically adds @i to @v and returns true
|
|
* if the result is negative, or false when
|
|
* result is greater than or equal to zero.
|
|
*/
|
|
#define atomic64_add_negative(i, v) (atomic64_add_return(i, (v)) < 0)
|
|
|
|
#else /* !CONFIG_64BIT */
|
|
|
|
#include <asm-generic/atomic64.h>
|
|
|
|
#endif /* CONFIG_64BIT */
|
|
|
|
/*
|
|
* atomic*_return operations are serializing but not the non-*_return
|
|
* versions.
|
|
*/
|
|
#define smp_mb__before_atomic_dec() smp_mb__before_llsc()
|
|
#define smp_mb__after_atomic_dec() smp_llsc_mb()
|
|
#define smp_mb__before_atomic_inc() smp_mb__before_llsc()
|
|
#define smp_mb__after_atomic_inc() smp_llsc_mb()
|
|
|
|
#include <asm-generic/atomic-long.h>
|
|
|
|
#endif /* _ASM_ATOMIC_H */
|