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Release 4.14 arch/hexagon/include/asm/atomic.h

/*
 * Atomic operations for the Hexagon architecture
 *
 * Copyright (c) 2010-2013, The Linux Foundation. All rights reserved.
 *
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 */

#ifndef _ASM_ATOMIC_H

#define _ASM_ATOMIC_H

#include <linux/types.h>
#include <asm/cmpxchg.h>
#include <asm/barrier.h>


#define ATOMIC_INIT(i)		{ (i) }

/*  Normal writes in our arch don't clear lock reservations  */


static inline void atomic_set(atomic_t *v, int new) { asm volatile( "1: r6 = memw_locked(%0);\n" " memw_locked(%0,p0) = %1;\n" " if (!P0) jump 1b;\n" : : "r" (&v->counter), "r" (new) : "memory", "p0", "r6" ); }

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Richard Kuo17100.00%2100.00%
Total17100.00%2100.00%

#define atomic_set_release(v, i) atomic_set((v), (i)) /** * atomic_read - reads a word, atomically * @v: pointer to atomic value * * Assumes all word reads on our architecture are atomic. */ #define atomic_read(v) READ_ONCE((v)->counter) /** * atomic_xchg - atomic * @v: pointer to memory to change * @new: new value (technically passed in a register -- see xchg) */ #define atomic_xchg(v, new) (xchg(&((v)->counter), (new))) /** * atomic_cmpxchg - atomic compare-and-exchange values * @v: pointer to value to change * @old: desired old value to match * @new: new value to put in * * Parameters are then pointer, value-in-register, value-in-register, * and the output is the old value. * * Apparently this is complicated for archs that don't support * the memw_locked like we do (or it's broken or whatever). * * Kind of the lynchpin of the rest of the generically defined routines. * Remember V2 had that bug with dotnew predicate set by memw_locked. * * "old" is "expected" old val, __oldval is actual old value */
static inline int atomic_cmpxchg(atomic_t *v, int old, int new) { int __oldval; asm volatile( "1: %0 = memw_locked(%1);\n" " { P0 = cmp.eq(%0,%2);\n" " if (!P0.new) jump:nt 2f; }\n" " memw_locked(%1,P0) = %3;\n" " if (!P0) jump 1b;\n" "2:\n" : "=&r" (__oldval) : "r" (&v->counter), "r" (old), "r" (new) : "memory", "p0" ); return __oldval; }

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Richard Kuo26100.00%1100.00%
Total26100.00%1100.00%

#define ATOMIC_OP(op) \ static inline void atomic_##op(int i, atomic_t *v) \ { \ int output; \ \ __asm__ __volatile__ ( \ "1: %0 = memw_locked(%1);\n" \ " %0 = "#op "(%0,%2);\n" \ " memw_locked(%1,P3)=%0;\n" \ " if !P3 jump 1b;\n" \ : "=&r" (output) \ : "r" (&v->counter), "r" (i) \ : "memory", "p3" \ ); \ } \ #define ATOMIC_OP_RETURN(op) \ static inline int atomic_##op##_return(int i, atomic_t *v) \ { \ int output; \ \ __asm__ __volatile__ ( \ "1: %0 = memw_locked(%1);\n" \ " %0 = "#op "(%0,%2);\n" \ " memw_locked(%1,P3)=%0;\n" \ " if !P3 jump 1b;\n" \ : "=&r" (output) \ : "r" (&v->counter), "r" (i) \ : "memory", "p3" \ ); \ return output; \ } #define ATOMIC_FETCH_OP(op) \ static inline int atomic_fetch_##op(int i, atomic_t *v) \ { \ int output, val; \ \ __asm__ __volatile__ ( \ "1: %0 = memw_locked(%2);\n" \ " %1 = "#op "(%0,%3);\n" \ " memw_locked(%2,P3)=%1;\n" \ " if !P3 jump 1b;\n" \ : "=&r" (output), "=&r" (val) \ : "r" (&v->counter), "r" (i) \ : "memory", "p3" \ ); \ return output; \ } #define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op) ATOMIC_OPS(add) ATOMIC_OPS(sub) #undef ATOMIC_OPS #define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op) ATOMIC_OPS(and) ATOMIC_OPS(or) ATOMIC_OPS(xor) #undef ATOMIC_OPS #undef ATOMIC_FETCH_OP #undef ATOMIC_OP_RETURN #undef ATOMIC_OP /** * __atomic_add_unless - add unless the number is a given value * @v: pointer to value * @a: amount to add * @u: unless value is equal to u * * Returns old value. * */
static inline int __atomic_add_unless(atomic_t *v, int a, int u) { int __oldval; register int tmp; asm volatile( "1: %0 = memw_locked(%2);" " {" " p3 = cmp.eq(%0, %4);" " if (p3.new) jump:nt 2f;" " %1 = add(%0, %3);" " }" " memw_locked(%2, p3) = %1;" " {" " if !p3 jump 1b;" " }" "2:" : "=&r" (__oldval), "=&r" (tmp) : "r" (v), "r" (a), "r" (u) : "memory", "p3" ); return __oldval; }

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Richard Kuo30100.00%2100.00%
Total30100.00%2100.00%

#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) #define atomic_inc(v) atomic_add(1, (v)) #define atomic_dec(v) atomic_sub(1, (v)) #define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0) #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) #define atomic_sub_and_test(i, v) (atomic_sub_return(i, (v)) == 0) #define atomic_add_negative(i, v) (atomic_add_return(i, (v)) < 0) #define atomic_inc_return(v) (atomic_add_return(1, v)) #define atomic_dec_return(v) (atomic_sub_return(1, v)) #endif

Overall Contributors

PersonTokensPropCommitsCommitProp
Richard Kuo18771.92%436.36%
Peter Zijlstra7026.92%654.55%
David Howells31.15%19.09%
Total260100.00%11100.00%
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