[PATCH v6 07/13] LoongArch: Atomic and Locking Routines

[Adhemerval Zanella Netto]

Although it would be to a more streamlined macros, it follows current practice.
Only a small nit below.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

On 08/07/22 03:52, caiyinyu wrote:
> ---
>  .../sysv/linux/loongarch/atomic-machine.h     | 181 ++++++++++++++++++
>  1 file changed, 181 insertions(+)
>  create mode 100644 sysdeps/unix/sysv/linux/loongarch/atomic-machine.h
> 
> diff --git a/sysdeps/unix/sysv/linux/loongarch/atomic-machine.h b/sysdeps/unix/sysv/linux/loongarch/atomic-machine.h
> new file mode 100644
> index 0000000000..60db25587e
> --- /dev/null
> +++ b/sysdeps/unix/sysv/linux/loongarch/atomic-machine.h
> @@ -0,0 +1,181 @@
> +/* Atomic operations.
> +   Copyright (C) 2022 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   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, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#ifndef _LINUX_LOONGARCH_BITS_ATOMIC_H
> +#define _LINUX_LOONGARCH_BITS_ATOMIC_H 1
> +
> +#define atomic_full_barrier() __sync_synchronize ()
> +
> +#define __HAVE_64B_ATOMICS (__loongarch_grlen >=64)

Missing space after >=

> +#define USE_ATOMIC_COMPILER_BUILTINS 1
> +#define ATOMIC_EXCHANGE_USES_CAS 0
> +
> +/* Compare and exchange.
> +   For all "bool" routines, we return FALSE if exchange succesful.  */
> +
> +#define __arch_compare_and_exchange_bool_8_int(mem, newval, oldval, model) \
> +  ({ \
> +    typeof (*mem) __oldval = (oldval); \
> +    !__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
> +				  __ATOMIC_RELAXED); \
> +  })
> +
> +#define __arch_compare_and_exchange_bool_16_int(mem, newval, oldval, model) \
> +  ({ \
> +    typeof (*mem) __oldval = (oldval); \
> +    !__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
> +				  __ATOMIC_RELAXED); \
> +  })
> +
> +#define __arch_compare_and_exchange_bool_32_int(mem, newval, oldval, model) \
> +  ({ \
> +    typeof (*mem) __oldval = (oldval); \
> +    !__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
> +				  __ATOMIC_RELAXED); \
> +  })
> +
> +#define __arch_compare_and_exchange_bool_64_int(mem, newval, oldval, model) \
> +  ({ \
> +    typeof (*mem) __oldval = (oldval); \
> +    !__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
> +				  __ATOMIC_RELAXED); \
> +  })
> +
> +#define __arch_compare_and_exchange_val_8_int(mem, newval, oldval, model) \
> +  ({ \
> +    typeof (*mem) __oldval = (oldval); \
> +    __atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
> +				 __ATOMIC_RELAXED); \
> +    __oldval; \
> +  })
> +
> +#define __arch_compare_and_exchange_val_16_int(mem, newval, oldval, model) \
> +  ({ \
> +    typeof (*mem) __oldval = (oldval); \
> +    __atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
> +				 __ATOMIC_RELAXED); \
> +    __oldval; \
> +  })
> +
> +#define __arch_compare_and_exchange_val_32_int(mem, newval, oldval, model) \
> +  ({ \
> +    typeof (*mem) __oldval = (oldval); \
> +    __atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
> +				 __ATOMIC_RELAXED); \
> +    __oldval; \
> +  })
> +
> +#define __arch_compare_and_exchange_val_64_int(mem, newval, oldval, model) \
> +  ({ \
> +    typeof (*mem) __oldval = (oldval); \
> +    __atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0, model, \
> +				 __ATOMIC_RELAXED); \
> +    __oldval; \
> +  })
> +
> +/* Atomic compare and exchange.  */
> +
> +#define atomic_compare_and_exchange_bool_acq(mem, new, old) \
> +  __atomic_bool_bysize (__arch_compare_and_exchange_bool, int, mem, new, old, \
> +			__ATOMIC_ACQUIRE)
> +
> +#define atomic_compare_and_exchange_val_acq(mem, new, old) \
> +  __atomic_val_bysize (__arch_compare_and_exchange_val, int, mem, new, old, \
> +		       __ATOMIC_ACQUIRE)
> +
> +#define atomic_compare_and_exchange_val_rel(mem, new, old) \
> +  __atomic_val_bysize (__arch_compare_and_exchange_val, int, mem, new, old, \
> +		       __ATOMIC_RELEASE)
> +
> +/* Atomic exchange (without compare).  */
> +
> +#define __arch_exchange_8_int(mem, newval, model) \
> +  __atomic_exchange_n (mem, newval, model)
> +
> +#define __arch_exchange_16_int(mem, newval, model) \
> +  __atomic_exchange_n (mem, newval, model)
> +
> +#define __arch_exchange_32_int(mem, newval, model) \
> +  __atomic_exchange_n (mem, newval, model)
> +
> +#define __arch_exchange_64_int(mem, newval, model) \
> +  __atomic_exchange_n (mem, newval, model)
> +
> +#define atomic_exchange_acq(mem, value) \
> +  __atomic_val_bysize (__arch_exchange, int, mem, value, __ATOMIC_ACQUIRE)
> +
> +#define atomic_exchange_rel(mem, value) \
> +  __atomic_val_bysize (__arch_exchange, int, mem, value, __ATOMIC_RELEASE)
> +
> +/* Atomically add value and return the previous (unincremented) value.  */
> +
> +#define __arch_exchange_and_add_8_int(mem, value, model) \
> +  __atomic_fetch_add (mem, value, model)
> +
> +#define __arch_exchange_and_add_16_int(mem, value, model) \
> +  __atomic_fetch_add (mem, value, model)
> +
> +#define __arch_exchange_and_add_32_int(mem, value, model) \
> +  __atomic_fetch_add (mem, value, model)
> +
> +#define __arch_exchange_and_add_64_int(mem, value, model) \
> +  __atomic_fetch_add (mem, value, model)
> +
> +#define atomic_exchange_and_add_acq(mem, value) \
> +  __atomic_val_bysize (__arch_exchange_and_add, int, mem, value, \
> +		       __ATOMIC_ACQUIRE)
> +
> +#define atomic_exchange_and_add_rel(mem, value) \
> +  __atomic_val_bysize (__arch_exchange_and_add, int, mem, value, \
> +		       __ATOMIC_RELEASE)
> +
> +/* Miscellaneous.  */
> +
> +#define asm_amo(which, mem, value) \
> +  ({ \
> +    __atomic_check_size (mem); \
> +    typeof (*mem) __tmp; \
> +    if (sizeof (__tmp) == 4) \
> +      asm volatile(which ".w" \
> +			 "\t%0, %z2, %1" \
> +		   : "=&r"(__tmp), "+ZB"(*(mem)) \
> +		   : "rJ"(value)); \
> +    else if (sizeof (__tmp) == 8) \

It does not have the case of !__HAVE_64B_ATOMICS, but since only 64-bit
is support I don think this will be troublesome.  Also, the idea is to
remove such atomic macros on next release.

> +      asm volatile(which ".d" \
> +			 "\t%0, %z2, %1" \
> +		   : "=&r"(__tmp), "+ZB"(*(mem)) \
> +		   : "rJ"(value)); \
> +    else \
> +      abort (); \
> +    __tmp; \
> +  })
> +
> +#define atomic_max(mem, value) asm_amo ("ammax_db", mem, value)
> +#define atomic_min(mem, value) asm_amo ("ammin_db", mem, value)
> +
> +#define atomic_bit_test_set(mem, bit) \
> +  ({ \
> +    typeof (*mem) __mask = (typeof (*mem)) 1 << (bit); \
> +    asm_amo ("amor_db", mem, __mask) & __mask; \
> +  })
> +
> +#define catomic_exchange_and_add(mem, value) \
> +  atomic_exchange_and_add (mem, value)
> +#define catomic_max(mem, value) atomic_max (mem, value)
> +
> +#endif /* bits/atomic.h */