| /* Internal macros for atomic operations for GNU C Library. |
| Copyright (C) 2002-2006, 2009 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@redhat.com>, 2002. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library 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 |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #ifndef _ATOMIC_H |
| #define _ATOMIC_H 1 |
| |
| /* This header defines three types of macros: |
| |
| - atomic arithmetic and logic operation on memory. They all |
| have the prefix "atomic_". |
| |
| - conditionally atomic operations of the same kinds. These |
| always behave identical but can be faster when atomicity |
| is not really needed since only one thread has access to |
| the memory location. In that case the code is slower in |
| the multi-thread case. The interfaces have the prefix |
| "catomic_". |
| |
| - support functions like barriers. They also have the preifx |
| "atomic_". |
| |
| Architectures must provide a few lowlevel macros (the compare |
| and exchange definitions). All others are optional. They |
| should only be provided if the architecture has specific |
| support for the operation. |
| |
| As <atomic.h> macros are usually heavily nested and often use local |
| variables to make sure side-effects are evaluated properly, use for |
| macro local variables a per-macro unique prefix. This file uses |
| __atgN_ prefix where N is different in each macro. */ |
| |
| #include <stdlib.h> |
| |
| #include <bits/atomic.h> |
| |
| /* Wrapper macros to call pre_NN_post (mem, ...) where NN is the |
| bit width of *MEM. The calling macro puts parens around MEM |
| and following args. */ |
| #define __atomic_val_bysize(pre, post, mem, ...) \ |
| ({ \ |
| __typeof (*mem) __atg1_result; \ |
| if (sizeof (*mem) == 1) \ |
| __atg1_result = pre##_8_##post (mem, __VA_ARGS__); \ |
| else if (sizeof (*mem) == 2) \ |
| __atg1_result = pre##_16_##post (mem, __VA_ARGS__); \ |
| else if (sizeof (*mem) == 4) \ |
| __atg1_result = pre##_32_##post (mem, __VA_ARGS__); \ |
| else if (sizeof (*mem) == 8) \ |
| __atg1_result = pre##_64_##post (mem, __VA_ARGS__); \ |
| else \ |
| abort (); \ |
| __atg1_result; \ |
| }) |
| #define __atomic_bool_bysize(pre, post, mem, ...) \ |
| ({ \ |
| int __atg2_result; \ |
| if (sizeof (*mem) == 1) \ |
| __atg2_result = pre##_8_##post (mem, __VA_ARGS__); \ |
| else if (sizeof (*mem) == 2) \ |
| __atg2_result = pre##_16_##post (mem, __VA_ARGS__); \ |
| else if (sizeof (*mem) == 4) \ |
| __atg2_result = pre##_32_##post (mem, __VA_ARGS__); \ |
| else if (sizeof (*mem) == 8) \ |
| __atg2_result = pre##_64_##post (mem, __VA_ARGS__); \ |
| else \ |
| abort (); \ |
| __atg2_result; \ |
| }) |
| |
| |
| /* Atomically store NEWVAL in *MEM if *MEM is equal to OLDVAL. |
| Return the old *MEM value. */ |
| #if !defined atomic_compare_and_exchange_val_acq \ |
| && defined __arch_compare_and_exchange_val_32_acq |
| # define atomic_compare_and_exchange_val_acq(mem, newval, oldval) \ |
| __atomic_val_bysize (__arch_compare_and_exchange_val,acq, \ |
| mem, newval, oldval) |
| #endif |
| |
| |
| #ifndef catomic_compare_and_exchange_val_acq |
| # ifdef __arch_c_compare_and_exchange_val_32_acq |
| # define catomic_compare_and_exchange_val_acq(mem, newval, oldval) \ |
| __atomic_val_bysize (__arch_c_compare_and_exchange_val,acq, \ |
| mem, newval, oldval) |
| # else |
| # define catomic_compare_and_exchange_val_acq(mem, newval, oldval) \ |
| atomic_compare_and_exchange_val_acq (mem, newval, oldval) |
| # endif |
| #endif |
| |
| |
| #ifndef catomic_compare_and_exchange_val_rel |
| # ifndef atomic_compare_and_exchange_val_rel |
| # define catomic_compare_and_exchange_val_rel(mem, newval, oldval) \ |
| catomic_compare_and_exchange_val_acq (mem, newval, oldval) |
| # else |
| # define catomic_compare_and_exchange_val_rel(mem, newval, oldval) \ |
| atomic_compare_and_exchange_val_rel (mem, newval, oldval) |
| # endif |
| #endif |
| |
| |
| #ifndef atomic_compare_and_exchange_val_rel |
| # define atomic_compare_and_exchange_val_rel(mem, newval, oldval) \ |
| atomic_compare_and_exchange_val_acq (mem, newval, oldval) |
| #endif |
| |
| |
| /* Atomically store NEWVAL in *MEM if *MEM is equal to OLDVAL. |
| Return zero if *MEM was changed or non-zero if no exchange happened. */ |
| #ifndef atomic_compare_and_exchange_bool_acq |
| # ifdef __arch_compare_and_exchange_bool_32_acq |
| # define atomic_compare_and_exchange_bool_acq(mem, newval, oldval) \ |
| __atomic_bool_bysize (__arch_compare_and_exchange_bool,acq, \ |
| mem, newval, oldval) |
| # else |
| # define atomic_compare_and_exchange_bool_acq(mem, newval, oldval) \ |
| ({ /* Cannot use __oldval here, because macros later in this file might \ |
| call this macro with __oldval argument. */ \ |
| __typeof (oldval) __atg3_old = (oldval); \ |
| atomic_compare_and_exchange_val_acq (mem, newval, __atg3_old) \ |
| != __atg3_old; \ |
| }) |
| # endif |
| #endif |
| |
| |
| #ifndef catomic_compare_and_exchange_bool_acq |
| # ifdef __arch_c_compare_and_exchange_bool_32_acq |
| # define catomic_compare_and_exchange_bool_acq(mem, newval, oldval) \ |
| __atomic_bool_bysize (__arch_c_compare_and_exchange_bool,acq, \ |
| mem, newval, oldval) |
| # else |
| # define catomic_compare_and_exchange_bool_acq(mem, newval, oldval) \ |
| ({ /* Cannot use __oldval here, because macros later in this file might \ |
| call this macro with __oldval argument. */ \ |
| __typeof (oldval) __atg4_old = (oldval); \ |
| catomic_compare_and_exchange_val_acq (mem, newval, __atg4_old) \ |
| != __atg4_old; \ |
| }) |
| # endif |
| #endif |
| |
| |
| #ifndef catomic_compare_and_exchange_bool_rel |
| # ifndef atomic_compare_and_exchange_bool_rel |
| # define catomic_compare_and_exchange_bool_rel(mem, newval, oldval) \ |
| catomic_compare_and_exchange_bool_acq (mem, newval, oldval) |
| # else |
| # define catomic_compare_and_exchange_bool_rel(mem, newval, oldval) \ |
| atomic_compare_and_exchange_bool_rel (mem, newval, oldval) |
| # endif |
| #endif |
| |
| |
| #ifndef atomic_compare_and_exchange_bool_rel |
| # define atomic_compare_and_exchange_bool_rel(mem, newval, oldval) \ |
| atomic_compare_and_exchange_bool_acq (mem, newval, oldval) |
| #endif |
| |
| |
| /* Store NEWVALUE in *MEM and return the old value. */ |
| #ifndef atomic_exchange_acq |
| # define atomic_exchange_acq(mem, newvalue) \ |
| ({ __typeof (*(mem)) __atg5_oldval; \ |
| __typeof (mem) __atg5_memp = (mem); \ |
| __typeof (*(mem)) __atg5_value = (newvalue); \ |
| \ |
| do \ |
| __atg5_oldval = *__atg5_memp; \ |
| while (__builtin_expect \ |
| (atomic_compare_and_exchange_bool_acq (__atg5_memp, __atg5_value, \ |
| __atg5_oldval), 0)); \ |
| \ |
| __atg5_oldval; }) |
| #endif |
| |
| #ifndef atomic_exchange_rel |
| # define atomic_exchange_rel(mem, newvalue) atomic_exchange_acq (mem, newvalue) |
| #endif |
| |
| |
| /* Add VALUE to *MEM and return the old value of *MEM. */ |
| #ifndef atomic_exchange_and_add |
| # define atomic_exchange_and_add(mem, value) \ |
| ({ __typeof (*(mem)) __atg6_oldval; \ |
| __typeof (mem) __atg6_memp = (mem); \ |
| __typeof (*(mem)) __atg6_value = (value); \ |
| \ |
| do \ |
| __atg6_oldval = *__atg6_memp; \ |
| while (__builtin_expect \ |
| (atomic_compare_and_exchange_bool_acq (__atg6_memp, \ |
| __atg6_oldval \ |
| + __atg6_value, \ |
| __atg6_oldval), 0)); \ |
| \ |
| __atg6_oldval; }) |
| #endif |
| |
| |
| #ifndef catomic_exchange_and_add |
| # define catomic_exchange_and_add(mem, value) \ |
| ({ __typeof (*(mem)) __atg7_oldv; \ |
| __typeof (mem) __atg7_memp = (mem); \ |
| __typeof (*(mem)) __atg7_value = (value); \ |
| \ |
| do \ |
| __atg7_oldv = *__atg7_memp; \ |
| while (__builtin_expect \ |
| (catomic_compare_and_exchange_bool_acq (__atg7_memp, \ |
| __atg7_oldv \ |
| + __atg7_value, \ |
| __atg7_oldv), 0)); \ |
| \ |
| __atg7_oldv; }) |
| #endif |
| |
| |
| #ifndef atomic_max |
| # define atomic_max(mem, value) \ |
| do { \ |
| __typeof (*(mem)) __atg8_oldval; \ |
| __typeof (mem) __atg8_memp = (mem); \ |
| __typeof (*(mem)) __atg8_value = (value); \ |
| do { \ |
| __atg8_oldval = *__atg8_memp; \ |
| if (__atg8_oldval >= __atg8_value) \ |
| break; \ |
| } while (__builtin_expect \ |
| (atomic_compare_and_exchange_bool_acq (__atg8_memp, __atg8_value,\ |
| __atg8_oldval), 0)); \ |
| } while (0) |
| #endif |
| |
| |
| #ifndef catomic_max |
| # define catomic_max(mem, value) \ |
| do { \ |
| __typeof (*(mem)) __atg9_oldv; \ |
| __typeof (mem) __atg9_memp = (mem); \ |
| __typeof (*(mem)) __atg9_value = (value); \ |
| do { \ |
| __atg9_oldv = *__atg9_memp; \ |
| if (__atg9_oldv >= __atg9_value) \ |
| break; \ |
| } while (__builtin_expect \ |
| (catomic_compare_and_exchange_bool_acq (__atg9_memp, \ |
| __atg9_value, \ |
| __atg9_oldv), 0)); \ |
| } while (0) |
| #endif |
| |
| |
| #ifndef atomic_min |
| # define atomic_min(mem, value) \ |
| do { \ |
| __typeof (*(mem)) __atg10_oldval; \ |
| __typeof (mem) __atg10_memp = (mem); \ |
| __typeof (*(mem)) __atg10_value = (value); \ |
| do { \ |
| __atg10_oldval = *__atg10_memp; \ |
| if (__atg10_oldval <= __atg10_value) \ |
| break; \ |
| } while (__builtin_expect \ |
| (atomic_compare_and_exchange_bool_acq (__atg10_memp, \ |
| __atg10_value, \ |
| __atg10_oldval), 0)); \ |
| } while (0) |
| #endif |
| |
| |
| #ifndef atomic_add |
| # define atomic_add(mem, value) (void) atomic_exchange_and_add ((mem), (value)) |
| #endif |
| |
| |
| #ifndef catomic_add |
| # define catomic_add(mem, value) \ |
| (void) catomic_exchange_and_add ((mem), (value)) |
| #endif |
| |
| |
| #ifndef atomic_increment |
| # define atomic_increment(mem) atomic_add ((mem), 1) |
| #endif |
| |
| |
| #ifndef catomic_increment |
| # define catomic_increment(mem) catomic_add ((mem), 1) |
| #endif |
| |
| |
| #ifndef atomic_increment_val |
| # define atomic_increment_val(mem) (atomic_exchange_and_add ((mem), 1) + 1) |
| #endif |
| |
| |
| #ifndef catomic_increment_val |
| # define catomic_increment_val(mem) (catomic_exchange_and_add ((mem), 1) + 1) |
| #endif |
| |
| |
| /* Add one to *MEM and return true iff it's now zero. */ |
| #ifndef atomic_increment_and_test |
| # define atomic_increment_and_test(mem) \ |
| (atomic_exchange_and_add ((mem), 1) + 1 == 0) |
| #endif |
| |
| |
| #ifndef atomic_decrement |
| # define atomic_decrement(mem) atomic_add ((mem), -1) |
| #endif |
| |
| |
| #ifndef catomic_decrement |
| # define catomic_decrement(mem) catomic_add ((mem), -1) |
| #endif |
| |
| |
| #ifndef atomic_decrement_val |
| # define atomic_decrement_val(mem) (atomic_exchange_and_add ((mem), -1) - 1) |
| #endif |
| |
| |
| #ifndef catomic_decrement_val |
| # define catomic_decrement_val(mem) (catomic_exchange_and_add ((mem), -1) - 1) |
| #endif |
| |
| |
| /* Subtract 1 from *MEM and return true iff it's now zero. */ |
| #ifndef atomic_decrement_and_test |
| # define atomic_decrement_and_test(mem) \ |
| (atomic_exchange_and_add ((mem), -1) == 1) |
| #endif |
| |
| |
| /* Decrement *MEM if it is > 0, and return the old value. */ |
| #ifndef atomic_decrement_if_positive |
| # define atomic_decrement_if_positive(mem) \ |
| ({ __typeof (*(mem)) __atg11_oldval; \ |
| __typeof (mem) __atg11_memp = (mem); \ |
| \ |
| do \ |
| { \ |
| __atg11_oldval = *__atg11_memp; \ |
| if (__builtin_expect (__atg11_oldval <= 0, 0)) \ |
| break; \ |
| } \ |
| while (__builtin_expect \ |
| (atomic_compare_and_exchange_bool_acq (__atg11_memp, \ |
| __atg11_oldval - 1, \ |
| __atg11_oldval), 0)); \ |
| __atg11_oldval; }) |
| #endif |
| |
| |
| #ifndef atomic_add_negative |
| # define atomic_add_negative(mem, value) \ |
| ({ __typeof (value) __atg12_value = (value); \ |
| atomic_exchange_and_add (mem, __atg12_value) < -__atg12_value; }) |
| #endif |
| |
| |
| #ifndef atomic_add_zero |
| # define atomic_add_zero(mem, value) \ |
| ({ __typeof (value) __atg13_value = (value); \ |
| atomic_exchange_and_add (mem, __atg13_value) == -__atg13_value; }) |
| #endif |
| |
| |
| #ifndef atomic_bit_set |
| # define atomic_bit_set(mem, bit) \ |
| (void) atomic_bit_test_set(mem, bit) |
| #endif |
| |
| |
| #ifndef atomic_bit_test_set |
| # define atomic_bit_test_set(mem, bit) \ |
| ({ __typeof (*(mem)) __atg14_old; \ |
| __typeof (mem) __atg14_memp = (mem); \ |
| __typeof (*(mem)) __atg14_mask = ((__typeof (*(mem))) 1 << (bit)); \ |
| \ |
| do \ |
| __atg14_old = (*__atg14_memp); \ |
| while (__builtin_expect \ |
| (atomic_compare_and_exchange_bool_acq (__atg14_memp, \ |
| __atg14_old | __atg14_mask,\ |
| __atg14_old), 0)); \ |
| \ |
| __atg14_old & __atg14_mask; }) |
| #endif |
| |
| /* Atomically *mem &= mask. */ |
| #ifndef atomic_and |
| # define atomic_and(mem, mask) \ |
| do { \ |
| __typeof (*(mem)) __atg15_old; \ |
| __typeof (mem) __atg15_memp = (mem); \ |
| __typeof (*(mem)) __atg15_mask = (mask); \ |
| \ |
| do \ |
| __atg15_old = (*__atg15_memp); \ |
| while (__builtin_expect \ |
| (atomic_compare_and_exchange_bool_acq (__atg15_memp, \ |
| __atg15_old & __atg15_mask, \ |
| __atg15_old), 0)); \ |
| } while (0) |
| #endif |
| |
| #ifndef catomic_and |
| # define catomic_and(mem, mask) \ |
| do { \ |
| __typeof (*(mem)) __atg20_old; \ |
| __typeof (mem) __atg20_memp = (mem); \ |
| __typeof (*(mem)) __atg20_mask = (mask); \ |
| \ |
| do \ |
| __atg20_old = (*__atg20_memp); \ |
| while (__builtin_expect \ |
| (catomic_compare_and_exchange_bool_acq (__atg20_memp, \ |
| __atg20_old & __atg20_mask,\ |
| __atg20_old), 0)); \ |
| } while (0) |
| #endif |
| |
| /* Atomically *mem &= mask and return the old value of *mem. */ |
| #ifndef atomic_and_val |
| # define atomic_and_val(mem, mask) \ |
| ({ __typeof (*(mem)) __atg16_old; \ |
| __typeof (mem) __atg16_memp = (mem); \ |
| __typeof (*(mem)) __atg16_mask = (mask); \ |
| \ |
| do \ |
| __atg16_old = (*__atg16_memp); \ |
| while (__builtin_expect \ |
| (atomic_compare_and_exchange_bool_acq (__atg16_memp, \ |
| __atg16_old & __atg16_mask,\ |
| __atg16_old), 0)); \ |
| \ |
| __atg16_old; }) |
| #endif |
| |
| /* Atomically *mem |= mask and return the old value of *mem. */ |
| #ifndef atomic_or |
| # define atomic_or(mem, mask) \ |
| do { \ |
| __typeof (*(mem)) __atg17_old; \ |
| __typeof (mem) __atg17_memp = (mem); \ |
| __typeof (*(mem)) __atg17_mask = (mask); \ |
| \ |
| do \ |
| __atg17_old = (*__atg17_memp); \ |
| while (__builtin_expect \ |
| (atomic_compare_and_exchange_bool_acq (__atg17_memp, \ |
| __atg17_old | __atg17_mask, \ |
| __atg17_old), 0)); \ |
| } while (0) |
| #endif |
| |
| #ifndef catomic_or |
| # define catomic_or(mem, mask) \ |
| do { \ |
| __typeof (*(mem)) __atg18_old; \ |
| __typeof (mem) __atg18_memp = (mem); \ |
| __typeof (*(mem)) __atg18_mask = (mask); \ |
| \ |
| do \ |
| __atg18_old = (*__atg18_memp); \ |
| while (__builtin_expect \ |
| (catomic_compare_and_exchange_bool_acq (__atg18_memp, \ |
| __atg18_old | __atg18_mask,\ |
| __atg18_old), 0)); \ |
| } while (0) |
| #endif |
| |
| /* Atomically *mem |= mask and return the old value of *mem. */ |
| #ifndef atomic_or_val |
| # define atomic_or_val(mem, mask) \ |
| ({ __typeof (*(mem)) __atg19_old; \ |
| __typeof (mem) __atg19_memp = (mem); \ |
| __typeof (*(mem)) __atg19_mask = (mask); \ |
| \ |
| do \ |
| __atg19_old = (*__atg19_memp); \ |
| while (__builtin_expect \ |
| (atomic_compare_and_exchange_bool_acq (__atg19_memp, \ |
| __atg19_old | __atg19_mask,\ |
| __atg19_old), 0)); \ |
| \ |
| __atg19_old; }) |
| #endif |
| |
| #ifndef atomic_full_barrier |
| # define atomic_full_barrier() __asm__ ("" ::: "memory") |
| #endif |
| |
| |
| #ifndef atomic_read_barrier |
| # define atomic_read_barrier() atomic_full_barrier () |
| #endif |
| |
| |
| #ifndef atomic_write_barrier |
| # define atomic_write_barrier() atomic_full_barrier () |
| #endif |
| |
| |
| #ifndef atomic_forced_read |
| # define atomic_forced_read(x) \ |
| ({ __typeof (x) __x; __asm__ ("" : "=r" (__x) : "0" (x)); __x; }) |
| #endif |
| |
| |
| #ifndef atomic_delay |
| # define atomic_delay() do { /* nothing */ } while (0) |
| #endif |
| |
| #endif /* atomic.h */ |