On 07/01/2020 11.14, Paolo Bonzini wrote: > On 07/01/20 11:03, Thomas Huth wrote: >>> >>> vm = QEMUMachine(iotests.qemu_prog) >>> -vm.add_args('-machine', 'accel=kvm:tcg') >>> +vm.add_args('-accel', 'kvm', '-accel', 'tcg') >> Looking at this, I wonder whether we really want the "-accel" option to >> prioritize the accelerators in the order of appearance? A lot of other >> CLI tools give the highest priority to the last parameter instead, e.g. >> "gcc -O3 -O1" compiles with -O1, and not with -O3. >> >> Also I think it might be quite common that there are shell scripts which >> call "qemu-system-xxx -accel xyz $*" ... and if we don't invert the >> priorities of -accel, it will be impossible to override -accel in that >> case... > > Hmm, it does match "-machine accel=kvm:tcg" and in general I think it's > more self-explanatory. However, it is indeed less friendly to scripts. > On one hand those could be changed to place "-accel xyz" after $* (or > better "$@"), on the other hand we could also add a priority option to > "-accel". What do you think?
I don't think we need a separate priority parameter here. But IMHO it's really rather common practice to prioritize the last option. So while it might be more "self-explanatory" to a CLI newbie if the first occurrence got the highest priority, it might be rather confusing instead for a CLI veteran...? What do others on the list here think about this? Thomas