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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 207.211.31.81 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , "Daniel P. Berrange" , Qemu-block , Markus Armbruster , QEMU Developers , Wainer dos Santos Moschetta , Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, Jan 7, 2020 at 1:34 PM Philippe Mathieu-Daud=C3=A9 wrote: > On 1/7/20 1:18 PM, Thomas Huth wrote: > > On 07/01/2020 11.14, Paolo Bonzini wrote: > >> On 07/01/20 11:03, Thomas Huth wrote: > >>>> > >>>> vm =3D QEMUMachine(iotests.qemu_prog) > >>>> -vm.add_args('-machine', 'accel=3Dkvm: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 othe= r > >>> 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 wh= ich > >>> call "qemu-system-xxx -accel xyz $*" ... and if we don't invert the > >>> priorities of -accel, it will be impossible to override -accel in tha= t > >>> case... > >> > >> Hmm, it does match "-machine accel=3Dkvm:tcg" and in general I think i= t's > >> more self-explanatory. However, it is indeed less friendly to scripts= . > >> On one hand those could be changed to place "-accel xyz" after $* (o= r > >> better "$@"), 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? > > We can make CLI more complex by adding a 'priority' option: > > -accel tcg,priority=3D1 -accel kvm,priority=3D0 I meant "more explicit" =3D)