Re: [Crash-utility] crash-4.0.2.12 PPC64 changes to make it understand64k pagesize

[Haren Myneni <hbabu@xxxxxxxxxx>]

crash-utility-bounces@xxxxxxxxxx wrote on 11/17/2005
12:56:01 PM:

> Badari Pulavarty wrote:
> 
> > Hi Dave & Haren,
> >
> > Here are the changes I made to "crash" to function
with PPC64
> > 64k pagesize. Instead of adding whole set of indexs, shifts,
> > masks, macros and new vtop() routines - I generalized 4-level
> > pagetable support and set & compute indexes, shift and masks
> > correctly for 4K and 64K.
> >
> > Tested with 4K pagesize and 64K pagesize kernels on PPC64.
> > Please review.
> 
> The proof is in the pudding, so I trust that it all works and is
> backwards-compatible -- but to cover my own ass, I need you
> to positively confirm that it still works on RHEL3 and RHEL4 kernels.

Let me run crash tool on RHEL4 vmcore (I believe,
I saved vmlinux and vmcore created on RHEL4 kernel). Yes, it should support
backward compatible since we did not change the previous code patch even
though we should be having one vtop with the new approach. But, we will
check on previous vmcore or on live RHEL4 kernel. 
> 
> One minor thing I can suggest, but I'll leave it up to you
> whether you want to add it.  On all of the other architectures,
> their xxx_dump_machdep_table() functions will display the
> contents of the generic machdep_table structure followed
> by the contents of their attached machine_specific structure.
> The ppc64_dump_machdep_table() function just has the
> machspec pointer.  When everything "just works", it's
usually
> never needed, but I've found it invaluable when debugging new
> machine-specific stuff that comes along.
> 
Yes, we will make changes.

> But it's your call... so when you and Haren are happy, just let
> me know.

Badari, Thanks a lot for doing this. This approach
is useful to support easily even for future changes. One minor comment,
instead of hardcoding in ppc64.c source file for 'm->l1_index_size =
9', can we define INDEX  macros in the header file and use them here.
For example, PTE_INDEX_SIZE_L4. I am thinking we can map/understand easily
to see what is l1 or l2. What do you think?

Thanks
Haren
 
> 
> Thanks,
>   Dave
> 
> 
> 
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