Re: [PATCH] x86: Merge setup_32/64.c into setup.c

[Ingo Molnar <mingo@elte.hu>]

* Yinghai Lu <yhlu.kernel@gmail.com> wrote:

> 
> Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
> 
> ---
>  arch/x86/kernel/Makefile   |    2 
>  arch/x86/kernel/setup.c    |  676 ++++++++++++++++++++++++++++++++++++++++++++-
>  arch/x86/kernel/setup_32.c |  543 ------------------------------------
>  arch/x86/kernel/setup_64.c |  381 -------------------------
>  include/asm-x86/setup.h    |    2 
>  5 files changed, 670 insertions(+), 934 deletions(-)

very nice!

could we please split this up into several, gradual steps that bring 
setup_32.c and setup_64.c to exactly the same content - where the final 
patch just renames arch/x86/kernel/setup_32.c to arch/x86/kernel/setup.c 
and deletes arch/x86/kernel/setup_64.c ?

it would still result in exactly the same end result - but is much more 
bisectable (and reviewable, etc.). A bit like how arch/x86/mm/ioremap.c 
or arch/x86/mm/pageattr.c was unified.

maybe it can be done in less than 10 patches - but it guess it should be 
rather something in the neighborhood of 20 patches. Changes like this:

-       /*
-        * NOTE: before this point _nobody_ is allowed to allocate
-        * any memory using the bootmem allocator.  Although the
-        * allocator is now initialised only the first 8Mb of the kernel
-        * virtual address space has been mapped.  All allocations before
-        * paging_init() has completed must use the alloc_bootmem_low_pages()
-        * variant (which allocates DMA'able memory) and care must be taken
-        * not to exceed the 8Mb limit.
-        */

should be in a separate patch - you removed this restriction from the 
x86 architecture via your earlier patches, so the removal of the comment 
comes from that (and deserves a separate commit), not purely from the 
mechanic unification in the end.

other changes like this:

-#ifdef CONFIG_X86_FIND_SMP_CONFIG
+#if defined(CONFIG_X86_FIND_SMP_CONFIG) && defined(CONFIG_X86_32) || \
+    defined(CONFIG_X86_MPPARSE) && defined(CONFIG_X86_64)

here you fix coding style:

-        /*
-         * Parse SRAT to discover nodes.
-         */
-        acpi_numa_init();
+       /*
+        * Parse SRAT to discover nodes.
+        */
+       acpi_numa_init();

etc. etc. You do a lot more very useful work than the plain single 
unification patch you sent tells us - all these changes should be split 
up.

[ and in the unlikely event of there being a bug somewhere in this 1600
  lines patch, a splitup is also useful for finding bugs :-) ]

	Ingo