Re: [Qemu-devel] [PATCH v10 5/8] module: implement module loading

["Daniel P. Berrange" <berrange@redhat.com>]

On Mon, Sep 16, 2013 at 12:18:54PM +0200, Paolo Bonzini wrote:
> Il 16/09/2013 12:14, Daniel P. Berrange ha scritto:
> > On Mon, Sep 16, 2013 at 12:09:47PM +0200, Paolo Bonzini wrote:
> >> Il 16/09/2013 11:51, Fam Zheng ha scritto:
> >>> On Mon, 09/16 11:44, Paolo Bonzini wrote:
> >>>> Il 16/09/2013 10:59, Daniel P. Berrange ha scritto:
> >>>>>> The init function of dynamic module is no longer with
> >>>>>> __attribute__((constructor)) as static linked version, and need to be
> >>>>>> explicitly called once loaded. The function name is mangled with per
> >>>>>> configure fingerprint as:
> >>>>>>
> >>>>>>     init_$(date +%s$$$RANDOM)
> >>>>
> >>>> Does this work for a module that calls module_init multiple times?
> >>>
> >>> Why should a module calls module_init, instead of the main function?
> >>
> >> I think you mean "why should a module calls register_module_init", and I
> >> agree that with this patch a module will not call register_module_init.
> >>
> >> But a module is still using the module_init macro.
> >>
> >> With this patch, a module will not be able to use the module_init macro
> >> twice.  I am not sure this is an acceptable limitation, especially if we
> >> do not have a dependency system within modules and/or load them with
> >> G_MODULE_LOCAL/RTLD_LOCAL.
> > 
> > Why would a module ever want to use the module_init macro twice ?
> 
> Because our coding standard is to have each source file do its own
> one-time initialization, using static functions and an invocation of
> module_init per source file.

Is there ever a case where two source files, each using module_init
will be compiled into the same .so loadable module. Looking at the
uses of block_init(), I don't see any obvious candidates for trouble,
all uses look like they'd be going into separate .so files.

Daniel
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