On Fri, Feb 27, 2015 at 03:10:27PM +0100, Andreas Färber wrote: > Am 26.02.2015 um 16:59 schrieb Eduardo Habkost: > > On Wed, Feb 25, 2015 at 11:06:55PM +0100, Andreas Färber wrote: > >> Am 25.02.2015 um 20:58 schrieb Eduardo Habkost: > >>> The function is used only for CONFIG_USER, so make its purpose clear. > >>> > >>> Reviewed-by: Paolo Bonzini <pbonz...@redhat.com> > >>> Signed-off-by: Eduardo Habkost <ehabk...@redhat.com> > >>> --- > >>> target-i386/cpu.c | 2 +- > >>> target-i386/cpu.h | 4 ++-- > >>> 2 files changed, 3 insertions(+), 3 deletions(-) > >> > >> Please don't. I happily got all architectures aligned that it's at least > >> cpu_something_init, and it only happens to be user-only for x86. It is > >> rather the legacy function that was used in both system and user. > > > > If that's a legacy function, what are the steps you plan to follow to > > eliminate it? I would be glad to help eliminating legacy code. > > > > Initialization of CPUs in *-user and *-softmmu is different in i386, so > > we are going to have different code for both. How do you think I should > > name the *-user-specific CPU init function in target-i386, then? > > I would prefer to leave its name as it is (unless we are renaming all, > which would probably be a waste of effort giving the next steps) and > simply not use it in PC code. If you want to enforce this, you could > #ifdef CONFIG_USER_ONLY it. > > For some targets - as can be seen in your uc32 patch - there is already > a cpu_generic_init() that calls into the CPUClass hooks of the given CPU > type. I would like to call that from linux-user directly (or from a > lightweight wrapper to be shared between linux-user and bsd-user, I > assume we're going need some target-specific #ifdefs) and drop > cpu_init() in its current form. In particular I want to somehow move the > realized=true part out of it, which means either inlining it into dozens > of machines or finishing the recursive realization work so that we only > need one central realized=true for /machine.
Moving realized=true outside cpu_generic_init() would make lots of sense for PC, as we already need to perform additional steps in the PC init code before realizing the CPU (and I expect the list of PC-specific CPU initialization steps to grow). And when we do this, cpu_x86_init() (used by CONFIG_USER) and cpu_x86_create() (used by PC) can become the same function. But I don't see how to implement this without requiring changing machine code case-by-case, as existing machine code may expect realized=true to be set very early and break if you don't set it immediately after cpu_*_init(). In other words, even if we implement recursive realization, we may need to inline realize=true on all machines as an intermediate (and automated) step, and then change machines to just rely on recursive realization, one by one. -- Eduardo
