tools/arch/arm64/include/asm/barrier.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _TOOLS_LINUX_ASM_AARCH64_BARRIER_H
   3 #define _TOOLS_LINUX_ASM_AARCH64_BARRIER_H
   4
   5 /*
   6  * From tools/perf/perf-sys.h, last modified in:
   7  * f428ebd184c82a7914b2aa7e9f868918aaf7ea78 perf tools: Fix AAAAARGH64 memory barriers
   8  *
   9  * XXX: arch/arm64/include/asm/barrier.h in the kernel sources use dsb, is this
  10  * a case like for arm32 where we do things differently in userspace?
  11  */
  12
  13 #define mb()            asm volatile("dmb ish" ::: "memory")
  14 #define wmb()           asm volatile("dmb ishst" ::: "memory")
  15 #define rmb()           asm volatile("dmb ishld" ::: "memory")
  16
  17 #define smp_store_release(p, v)                                 \
  18 do {                                                            \
  19         union { typeof(*p) __val; char __c[1]; } __u =          \
  20                 { .__val = (__force typeof(*p)) (v) };          \
  21                                                                 \
  22         switch (sizeof(*p)) {                                   \
  23         case 1:                                                 \
  24                 asm volatile ("stlrb %w1, %0"                   \
  25                                 : "=Q" (*p)                     \
  26                                 : "r" (*(__u8 *)__u.__c)        \
  27                                 : "memory");                    \
  28                 break;                                          \
  29         case 2:                                                 \
  30                 asm volatile ("stlrh %w1, %0"                   \
  31                                 : "=Q" (*p)                     \
  32                                 : "r" (*(__u16 *)__u.__c)       \
  33                                 : "memory");                    \
  34                 break;                                          \
  35         case 4:                                                 \
  36                 asm volatile ("stlr %w1, %0"                    \
  37                                 : "=Q" (*p)                     \
  38                                 : "r" (*(__u32 *)__u.__c)       \
  39                                 : "memory");                    \
  40                 break;                                          \
  41         case 8:                                                 \
  42                 asm volatile ("stlr %1, %0"                     \
  43                                 : "=Q" (*p)                     \
  44                                 : "r" (*(__u64 *)__u.__c)       \
  45                                 : "memory");                    \
  46                 break;                                          \
  47         default:                                                \
  48                 /* Only to shut up gcc ... */                   \
  49                 mb();                                           \
  50                 break;                                          \
  51         }                                                       \
  52 } while (0)
  53
  54 #define smp_load_acquire(p)                                     \
  55 ({                                                              \
  56         union { typeof(*p) __val; char __c[1]; } __u;           \
  57                                                                 \
  58         switch (sizeof(*p)) {                                   \
  59         case 1:                                                 \
  60                 asm volatile ("ldarb %w0, %1"                   \
  61                         : "=r" (*(__u8 *)__u.__c)               \
  62                         : "Q" (*p) : "memory");                 \
  63                 break;                                          \
  64         case 2:                                                 \
  65                 asm volatile ("ldarh %w0, %1"                   \
  66                         : "=r" (*(__u16 *)__u.__c)              \
  67                         : "Q" (*p) : "memory");                 \
  68                 break;                                          \
  69         case 4:                                                 \
  70                 asm volatile ("ldar %w0, %1"                    \
  71                         : "=r" (*(__u32 *)__u.__c)              \
  72                         : "Q" (*p) : "memory");                 \
  73                 break;                                          \
  74         case 8:                                                 \
  75                 asm volatile ("ldar %0, %1"                     \
  76                         : "=r" (*(__u64 *)__u.__c)              \
  77                         : "Q" (*p) : "memory");                 \
  78                 break;                                          \
  79         default:                                                \
  80                 /* Only to shut up gcc ... */                   \
  81                 mb();                                           \
  82                 break;                                          \
  83         }                                                       \
  84         __u.__val;                                              \
  85 })
  86
  87 #endif /* _TOOLS_LINUX_ASM_AARCH64_BARRIER_H */