Re: [patch] mm: node-setup agnostic free_bootmem()

[Johannes Weiner <hannes@saeurebad.de>]

Hi Ingo,

Ingo Molnar <mingo@elte.hu> writes:

> * Johannes Weiner <hannes@saeurebad.de> wrote:
>
>> > so i very much agree that your changes are cleaner, i just wanted to 
>> > have one that has all the fixes included.
>> 
>> I had planned this to be another patch because there are more then one 
>> boundary check I wanted to tighten.  I can merge them though if you 
>> like.
>
> no, better to have them in separate patches.

Okay.

>> > Would you like to post a patch against current -git or should i 
>> > extract the cleaner reserve_bootmem() from your previous patch?
>> 
>> I just moved and have only sporadic internet access and free time 
>> slots available.  Would be nice if you could do it!
>
> sure, find the merged patch below, against latest -git, boot-tested on 
> x86. Is this what you had in mind?
>
> 	Ingo
>
> ---------------->
> Subject: mm: node-setup agnostic free_bootmem()
> From: Johannes Weiner <hannes@saeurebad.de>
> Date: Wed, 16 Apr 2008 13:36:31 +0200
>
> Make free_bootmem() look up the node holding the specified address
> range which lets it work transparently on single-node and multi-node
> configurations.
>
> If the address range exceeds the node range, it well be marked free
> across node boundaries, too.
>
> Signed-off-by: Johannes Weiner <hannes@saeurebad.de>
> CC: Andi Kleen <andi@firstfloor.org>
> CC: Yinghai Lu <yhlu.kernel@gmail.com>
> CC: Yasunori Goto <y-goto@jp.fujitsu.com>
> CC: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
> CC: Christoph Lameter <clameter@sgi.com>
> CC: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Ingo Molnar <mingo@elte.hu>
> ---
>  mm/bootmem.c |   27 +++++++++++++++++++++++++--
>  1 file changed, 25 insertions(+), 2 deletions(-)
>
> Index: linux-x86.q/mm/bootmem.c
> ===================================================================
> --- linux-x86.q.orig/mm/bootmem.c
> +++ linux-x86.q/mm/bootmem.c
> @@ -493,8 +493,31 @@ int __init reserve_bootmem(unsigned long
>  void __init free_bootmem(unsigned long addr, unsigned long size)
>  {
>  	bootmem_data_t *bdata;
> -	list_for_each_entry(bdata, &bdata_list, list)
> -		free_bootmem_core(bdata, addr, size);
> +	unsigned long pos = addr;
> +	unsigned long partsize = size;
> +
> +	list_for_each_entry(bdata, &bdata_list, list) {
> +		unsigned long remainder = 0;
> +
> +		if (pos < bdata->node_boot_start)
> +			continue;
> +
> +		if (PFN_DOWN(pos + partsize) > bdata->node_low_pfn) {
> +			remainder = PFN_DOWN(pos + partsize) - bdata->node_low_pfn;
> +			partsize -= remainder;
> +		}
> +
> +		free_bootmem_core(bdata, pos, partsize);
> +
> +		if (!remainder)
> +			return;
> +
> +		pos = PFN_PHYS(bdata->node_low_pfn + 1);
> +	}
> +	printk(KERN_ERR "free_bootmem: request: addr=%lx, size=%lx, "
> +			"state: pos=%lx, partsize=%lx\n", addr, size,
> +			pos, partsize);
> +	BUG();
>  }
>  
>  unsigned long __init free_all_bootmem(void)

Yes, looks good.  But needs explicit testing, I guess.

	Hannes