xref: /kernel/linux/linux-5.10/tools/virtio/asm/barrier.h (revision 8c2ecf20)
  • Home
  • History
  • Annotate Annotate
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
  • only in /kernel/linux/linux-5.10/tools/virtio/asm/
18c2ecf20Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0 */
28c2ecf20Sopenharmony_ci#include <stdlib.h>
38c2ecf20Sopenharmony_ci#if defined(__i386__) || defined(__x86_64__)
48c2ecf20Sopenharmony_ci#define barrier() asm volatile("" ::: "memory")
58c2ecf20Sopenharmony_ci#define virt_mb() __sync_synchronize()
68c2ecf20Sopenharmony_ci#define virt_rmb() barrier()
78c2ecf20Sopenharmony_ci#define virt_wmb() barrier()
88c2ecf20Sopenharmony_ci/* Atomic store should be enough, but gcc generates worse code in that case. */
98c2ecf20Sopenharmony_ci#define virt_store_mb(var, value)  do { \
108c2ecf20Sopenharmony_ci	typeof(var) virt_store_mb_value = (value); \
118c2ecf20Sopenharmony_ci	__atomic_exchange(&(var), &virt_store_mb_value, &virt_store_mb_value, \
128c2ecf20Sopenharmony_ci			  __ATOMIC_SEQ_CST); \
138c2ecf20Sopenharmony_ci	barrier(); \
148c2ecf20Sopenharmony_ci} while (0);
158c2ecf20Sopenharmony_ci/* Weak barriers should be used. If not - it's a bug */
168c2ecf20Sopenharmony_ci# define mb() abort()
178c2ecf20Sopenharmony_ci# define dma_rmb() abort()
188c2ecf20Sopenharmony_ci# define dma_wmb() abort()
198c2ecf20Sopenharmony_ci#else
208c2ecf20Sopenharmony_ci#error Please fill in barrier macros
218c2ecf20Sopenharmony_ci#endif
228c2ecf20Sopenharmony_ci
23

Indexes created Thu Nov 07 10:32:03 CST 2024