Subject: Re: [PATCH 1/3] powerpc: bare minimum checkpoint/restart implementation

From: "Serge E. Hallyn" <[email-masked]>
Date: Wed, 4 Feb 2009 09:54:06 -0600

Quoting Benjamin Herrenschmidt ([email-masked]):
> 
> > +struct cr_hdr_cpu {
> > +	struct pt_regs pt_regs;
> > +	/* relevant fields from thread_struct */
> > +	double fpr[32][TS_FPRWIDTH];
> > +	unsigned int fpscr;
> > +	int fpexc_mode;
> > +	/* unsigned int align_ctl; this is never updated? */
> > +	unsigned long dabr;
> > +};
> 
> Is there some version or other identification somewhere ? If not there
> should be. ie, we're going to add things here. For example, what about
> the vector registers ? Also, some CPUs will have more HW debug registers
> than just the DABR (we plan to add support for all the BookE architected
> IACs and DACs for example), etc...

The arch-independent checkpoint header does have kernel
maj:min:rev:patch info.  We expect to have to do more,
assuming that the .config can change the arch-dependent
cpu header (i.e. perhaps TS_FPRWIDTH could be changed).

-serge