On 11/18/22 05:17, Janis Schoetterl-Glausch wrote: > +For write accesses, the KVM_S390_MEMOP_F_CMPXCHG might be supported. > +In this case, instead of doing an unconditional write, the access occurs only > +if the target location contains the "size" byte long value pointed to by > +"old_p". This is performed as an atomic cmpxchg. "size" must be a power of two > +up to and including 16. > +The value at the target location is written to the location "old_p" points to. > +If the exchange did not take place because the target value doesn't match the > +old value KVM_S390_MEMOP_R_NO_XCHG is returned. > +The KVM_S390_MEMOP_F_CMPXCHG flag is supported if KVM_CAP_S390_MEM_OP_EXTENSION > +has bit 1 (i.e. bit with value 2) set. > Is KVM_S390_MEMOP_F_CMPXCHG supported with conditions (as you implied)? -- An old man doll... just what I always wanted! - Clara