atomic: update documentation

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2017-09-21 14:44:08 +02:00
parent 05e015f73c
commit db81b99537
1 changed files with 12 additions and 1 deletions

View File

@ -63,11 +63,22 @@ operations:
typeof(*ptr) atomic_fetch_sub(ptr, val)
typeof(*ptr) atomic_fetch_and(ptr, val)
typeof(*ptr) atomic_fetch_or(ptr, val)
typeof(*ptr) atomic_fetch_xor(ptr, val)
typeof(*ptr) atomic_xchg(ptr, val)
typeof(*ptr) atomic_cmpxchg(ptr, old, new)
all of which return the old value of *ptr. These operations are
polymorphic; they operate on any type that is as wide as an int.
polymorphic; they operate on any type that is as wide as a pointer.
Similar operations return the new value of *ptr:
typeof(*ptr) atomic_inc_fetch(ptr)
typeof(*ptr) atomic_dec_fetch(ptr)
typeof(*ptr) atomic_add_fetch(ptr, val)
typeof(*ptr) atomic_sub_fetch(ptr, val)
typeof(*ptr) atomic_and_fetch(ptr, val)
typeof(*ptr) atomic_or_fetch(ptr, val)
typeof(*ptr) atomic_xor_fetch(ptr, val)
Sequentially consistent loads and stores can be done using: