| // SPDX-License-Identifier: GPL-2.0+ |
| // |
| // An earlier version of this file appeared in the companion webpage for |
| // "Frightening small children and disconcerting grown-ups: Concurrency |
| // in the Linux kernel" by Alglave, Maranget, McKenney, Parri, and Stern, |
| // which appeared in ASPLOS 2018. |
| |
| // ONCE |
| READ_ONCE(X) __load{once}(X) |
| WRITE_ONCE(X,V) { __store{once}(X,V); } |
| |
| // Release Acquire and friends |
| smp_store_release(X,V) { __store{release}(*X,V); } |
| smp_load_acquire(X) __load{acquire}(*X) |
| rcu_assign_pointer(X,V) { __store{release}(X,V); } |
| rcu_dereference(X) __load{once}(X) |
| smp_store_mb(X,V) { __store{once}(X,V); __fence{mb}; } |
| |
| // Fences |
| smp_mb() { __fence{mb}; } |
| smp_rmb() { __fence{rmb}; } |
| smp_wmb() { __fence{wmb}; } |
| smp_mb__before_atomic() { __fence{before-atomic}; } |
| smp_mb__after_atomic() { __fence{after-atomic}; } |
| smp_mb__after_spinlock() { __fence{after-spinlock}; } |
| smp_mb__after_unlock_lock() { __fence{after-unlock-lock}; } |
| |
| // Exchange |
| xchg(X,V) __xchg{mb}(X,V) |
| xchg_relaxed(X,V) __xchg{once}(X,V) |
| xchg_release(X,V) __xchg{release}(X,V) |
| xchg_acquire(X,V) __xchg{acquire}(X,V) |
| cmpxchg(X,V,W) __cmpxchg{mb}(X,V,W) |
| cmpxchg_relaxed(X,V,W) __cmpxchg{once}(X,V,W) |
| cmpxchg_acquire(X,V,W) __cmpxchg{acquire}(X,V,W) |
| cmpxchg_release(X,V,W) __cmpxchg{release}(X,V,W) |
| |
| // Spinlocks |
| spin_lock(X) { __lock(X); } |
| spin_unlock(X) { __unlock(X); } |
| spin_trylock(X) __trylock(X) |
| spin_is_locked(X) __islocked(X) |
| |
| // RCU |
| rcu_read_lock() { __fence{rcu-lock}; } |
| rcu_read_unlock() { __fence{rcu-unlock}; } |
| synchronize_rcu() { __fence{sync-rcu}; } |
| synchronize_rcu_expedited() { __fence{sync-rcu}; } |
| |
| // Atomic |
| atomic_read(X) READ_ONCE(*X) |
| atomic_set(X,V) { WRITE_ONCE(*X,V); } |
| atomic_read_acquire(X) smp_load_acquire(X) |
| atomic_set_release(X,V) { smp_store_release(X,V); } |
| |
| atomic_add(V,X) { __atomic_op(X,+,V); } |
| atomic_sub(V,X) { __atomic_op(X,-,V); } |
| atomic_inc(X) { __atomic_op(X,+,1); } |
| atomic_dec(X) { __atomic_op(X,-,1); } |
| |
| atomic_add_return(V,X) __atomic_op_return{mb}(X,+,V) |
| atomic_add_return_relaxed(V,X) __atomic_op_return{once}(X,+,V) |
| atomic_add_return_acquire(V,X) __atomic_op_return{acquire}(X,+,V) |
| atomic_add_return_release(V,X) __atomic_op_return{release}(X,+,V) |
| atomic_fetch_add(V,X) __atomic_fetch_op{mb}(X,+,V) |
| atomic_fetch_add_relaxed(V,X) __atomic_fetch_op{once}(X,+,V) |
| atomic_fetch_add_acquire(V,X) __atomic_fetch_op{acquire}(X,+,V) |
| atomic_fetch_add_release(V,X) __atomic_fetch_op{release}(X,+,V) |
| |
| atomic_inc_return(X) __atomic_op_return{mb}(X,+,1) |
| atomic_inc_return_relaxed(X) __atomic_op_return{once}(X,+,1) |
| atomic_inc_return_acquire(X) __atomic_op_return{acquire}(X,+,1) |
| atomic_inc_return_release(X) __atomic_op_return{release}(X,+,1) |
| atomic_fetch_inc(X) __atomic_fetch_op{mb}(X,+,1) |
| atomic_fetch_inc_relaxed(X) __atomic_fetch_op{once}(X,+,1) |
| atomic_fetch_inc_acquire(X) __atomic_fetch_op{acquire}(X,+,1) |
| atomic_fetch_inc_release(X) __atomic_fetch_op{release}(X,+,1) |
| |
| atomic_sub_return(V,X) __atomic_op_return{mb}(X,-,V) |
| atomic_sub_return_relaxed(V,X) __atomic_op_return{once}(X,-,V) |
| atomic_sub_return_acquire(V,X) __atomic_op_return{acquire}(X,-,V) |
| atomic_sub_return_release(V,X) __atomic_op_return{release}(X,-,V) |
| atomic_fetch_sub(V,X) __atomic_fetch_op{mb}(X,-,V) |
| atomic_fetch_sub_relaxed(V,X) __atomic_fetch_op{once}(X,-,V) |
| atomic_fetch_sub_acquire(V,X) __atomic_fetch_op{acquire}(X,-,V) |
| atomic_fetch_sub_release(V,X) __atomic_fetch_op{release}(X,-,V) |
| |
| atomic_dec_return(X) __atomic_op_return{mb}(X,-,1) |
| atomic_dec_return_relaxed(X) __atomic_op_return{once}(X,-,1) |
| atomic_dec_return_acquire(X) __atomic_op_return{acquire}(X,-,1) |
| atomic_dec_return_release(X) __atomic_op_return{release}(X,-,1) |
| atomic_fetch_dec(X) __atomic_fetch_op{mb}(X,-,1) |
| atomic_fetch_dec_relaxed(X) __atomic_fetch_op{once}(X,-,1) |
| atomic_fetch_dec_acquire(X) __atomic_fetch_op{acquire}(X,-,1) |
| atomic_fetch_dec_release(X) __atomic_fetch_op{release}(X,-,1) |
| |
| atomic_xchg(X,V) __xchg{mb}(X,V) |
| atomic_xchg_relaxed(X,V) __xchg{once}(X,V) |
| atomic_xchg_release(X,V) __xchg{release}(X,V) |
| atomic_xchg_acquire(X,V) __xchg{acquire}(X,V) |
| atomic_cmpxchg(X,V,W) __cmpxchg{mb}(X,V,W) |
| atomic_cmpxchg_relaxed(X,V,W) __cmpxchg{once}(X,V,W) |
| atomic_cmpxchg_acquire(X,V,W) __cmpxchg{acquire}(X,V,W) |
| atomic_cmpxchg_release(X,V,W) __cmpxchg{release}(X,V,W) |
| |
| atomic_sub_and_test(V,X) __atomic_op_return{mb}(X,-,V) == 0 |
| atomic_dec_and_test(X) __atomic_op_return{mb}(X,-,1) == 0 |
| atomic_inc_and_test(X) __atomic_op_return{mb}(X,+,1) == 0 |
| atomic_add_negative(V,X) __atomic_op_return{mb}(X,+,V) < 0 |
