Index: kernel/arch/ia32/include/arch/atomic.h =================================================================== --- kernel/arch/ia32/include/arch/atomic.h (revision 7328ff41dcbe15332d62c013417ec72bbb613ee6) +++ (revision ) @@ -1,251 +1,0 @@ -/* - * Copyright (c) 2001-2004 Jakub Jermar - * Copyright (c) 2012 Adam Hraska - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * - * - Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * - Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * - The name of the author may not be used to endorse or promote products - * derived from this software without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR - * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES - * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. - * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, - * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT - * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, - * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY - * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF - * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - */ - -/** @addtogroup ia32 - * @{ - */ -/** @file - */ - -#ifndef KERN_ia32_ATOMIC_H_ -#define KERN_ia32_ATOMIC_H_ - -#include -#include -#include -#include - -NO_TRACE static inline void atomic_inc(atomic_t *val) -{ -#ifdef CONFIG_SMP - asm volatile ( - "lock incl %[count]\n" - : [count] "+m" (val->count) - ); -#else - asm volatile ( - "incl %[count]\n" - : [count] "+m" (val->count) - ); -#endif /* CONFIG_SMP */ -} - -NO_TRACE static inline void atomic_dec(atomic_t *val) -{ -#ifdef CONFIG_SMP - asm volatile ( - "lock decl %[count]\n" - : [count] "+m" (val->count) - ); -#else - asm volatile ( - "decl %[count]\n" - : [count] "+m" (val->count) - ); -#endif /* CONFIG_SMP */ -} - -NO_TRACE static inline atomic_count_t atomic_postinc(atomic_t *val) -{ - atomic_count_t r = 1; - - asm volatile ( - "lock xaddl %[r], %[count]\n" - : [count] "+m" (val->count), - [r] "+r" (r) - ); - - return r; -} - -NO_TRACE static inline atomic_count_t atomic_postdec(atomic_t *val) -{ - atomic_count_t r = -1; - - asm volatile ( - "lock xaddl %[r], %[count]\n" - : [count] "+m" (val->count), - [r] "+r" (r) - ); - - return r; -} - -#define atomic_preinc(val) (atomic_postinc(val) + 1) -#define atomic_predec(val) (atomic_postdec(val) - 1) - -NO_TRACE static inline atomic_count_t test_and_set(atomic_t *val) -{ - atomic_count_t v = 1; - - asm volatile ( - "xchgl %[v], %[count]\n" - : [v] "+r" (v), - [count] "+m" (val->count) - ); - - return v; -} - - -/** ia32 specific fast spinlock */ -NO_TRACE static inline void atomic_lock_arch(atomic_t *val) -{ - atomic_count_t tmp; - - preemption_disable(); - asm volatile ( - "0:\n" -#ifndef PROCESSOR_i486 - "pause\n" /* Pentium 4's HT love this instruction */ -#endif - "mov %[count], %[tmp]\n" - "testl %[tmp], %[tmp]\n" - "jnz 0b\n" /* lightweight looping on locked spinlock */ - - "incl %[tmp]\n" /* now use the atomic operation */ - "xchgl %[count], %[tmp]\n" - "testl %[tmp], %[tmp]\n" - "jnz 0b\n" - : [count] "+m" (val->count), - [tmp] "=&r" (tmp) - ); - - /* - * Prevent critical section code from bleeding out this way up. - */ - CS_ENTER_BARRIER(); -} - - -#define _atomic_cas_impl(pptr, exp_val, new_val, old_val, prefix) \ -({ \ - switch (sizeof(typeof(*(pptr)))) { \ - case 1: \ - asm volatile ( \ - prefix " cmpxchgb %[newval], %[ptr]\n" \ - : /* Output operands. */ \ - /* Old/current value is returned in eax. */ \ - [oldval] "=a" (old_val), \ - /* (*ptr) will be read and written to, hence "+" */ \ - [ptr] "+m" (*pptr) \ - : /* Input operands. */ \ - /* Expected value must be in eax. */ \ - [expval] "a" (exp_val), \ - /* The new value may be in any register. */ \ - [newval] "r" (new_val) \ - : "memory" \ - ); \ - break; \ - case 2: \ - asm volatile ( \ - prefix " cmpxchgw %[newval], %[ptr]\n" \ - : /* Output operands. */ \ - /* Old/current value is returned in eax. */ \ - [oldval] "=a" (old_val), \ - /* (*ptr) will be read and written to, hence "+" */ \ - [ptr] "+m" (*pptr) \ - : /* Input operands. */ \ - /* Expected value must be in eax. */ \ - [expval] "a" (exp_val), \ - /* The new value may be in any register. */ \ - [newval] "r" (new_val) \ - : "memory" \ - ); \ - break; \ - case 4: \ - asm volatile ( \ - prefix " cmpxchgl %[newval], %[ptr]\n" \ - : /* Output operands. */ \ - /* Old/current value is returned in eax. */ \ - [oldval] "=a" (old_val), \ - /* (*ptr) will be read and written to, hence "+" */ \ - [ptr] "+m" (*pptr) \ - : /* Input operands. */ \ - /* Expected value must be in eax. */ \ - [expval] "a" (exp_val), \ - /* The new value may be in any register. */ \ - [newval] "r" (new_val) \ - : "memory" \ - ); \ - break; \ - } \ -}) - - -#ifndef local_atomic_cas - -#define local_atomic_cas(pptr, exp_val, new_val) \ -({ \ - /* Use proper types and avoid name clashes */ \ - typeof(*(pptr)) _old_val_cas; \ - typeof(*(pptr)) _exp_val_cas = exp_val; \ - typeof(*(pptr)) _new_val_cas = new_val; \ - _atomic_cas_impl(pptr, _exp_val_cas, _new_val_cas, _old_val_cas, ""); \ - \ - _old_val_cas; \ -}) - -#else -/* Check if arch/atomic.h does not accidentally include /atomic.h .*/ -#error Architecture specific cpu local atomics already defined! Check your includes. -#endif - - -#ifndef local_atomic_exchange -/* - * Issuing a xchg instruction always implies lock prefix semantics. - * Therefore, it is cheaper to use a cmpxchg without a lock prefix - * in a loop. - */ -#define local_atomic_exchange(pptr, new_val) \ -({ \ - /* Use proper types and avoid name clashes */ \ - typeof(*(pptr)) _exp_val_x; \ - typeof(*(pptr)) _old_val_x; \ - typeof(*(pptr)) _new_val_x = new_val; \ - \ - do { \ - _exp_val_x = *pptr; \ - _old_val_x = local_atomic_cas(pptr, _exp_val_x, _new_val_x); \ - } while (_old_val_x != _exp_val_x); \ - \ - _old_val_x; \ -}) - -#else -/* Check if arch/atomic.h does not accidentally include /atomic.h .*/ -#error Architecture specific cpu local atomics already defined! Check your includes. -#endif - - -#endif - -/** @} - */