include/urcu/uatomic/riscv.h

   1 // SPDX-FileCopyrightText: 2018 Michael Jeanson <mjeanson@efficios.com>
   2 //
   3 // SPDX-License-Identifier: MIT
   4
   5 /*
   6  * Atomic exchange operations for the RISC-V architecture.
   7  *
   8  * Let the compiler do it.
   9  */
  10
  11 #ifndef _URCU_ARCH_UATOMIC_RISCV_H
  12 #define _URCU_ARCH_UATOMIC_RISCV_H
  13
  14 #include <urcu/compiler.h>
  15 #include <urcu/system.h>
  16
  17 /*
  18  * See <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104831> for details.
  19  *
  20  * The following GCC patches are required to have a working Userspace RCU on
  21  * the RISC-V architecture. The were introduced in GCC 14 and backported to
  22  * 13.3.0.
  23  *
  24  *  - <https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=dcd7b2f5f7233a04c8b14b362d0befa76e9654c0>
  25  *  - <https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=4990cf84c460f064d6281d0813f20b0ef20c7448>
  26  *  - <https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=d199d2e56da2379004e7e0457150409c0c99d3e6>
  27  */
  28 #ifdef URCU_GCC_VERSION
  29 # if (URCU_GCC_VERSION < 130300)
  30 #  error "Implementations of some atomic operations of GCC < 13.3.0 for RISC-V are insufficient for sequential consistency. For this reason Userspace RCU is currently marked as 'broken' for RISC-V on these GCC versions."
  31 # endif
  32 #endif
  33
  34 #ifdef __cplusplus
  35 extern "C" {
  36 #endif
  37
  38 #define UATOMIC_HAS_ATOMIC_BYTE
  39 #define UATOMIC_HAS_ATOMIC_SHORT
  40
  41 #ifdef __cplusplus
  42 }
  43 #endif
  44
  45 #include <urcu/uatomic/generic.h>
  46
  47 #endif /* _URCU_ARCH_UATOMIC_RISCV_H */