Re: [PATCH v3 1/2] x86/numa: Introduce numa_fill_memblks()

[Alison Schofield]

On Sat, Jun 24, 2023 at 11:01:38PM -0700, Dan Williams wrote:
> alison.schofield@ wrote:
> > From: Alison Schofield <alison.schofield@xxxxxxxxx>
> > 
> > numa_fill_memblks() fills in the gaps in numa_meminfo memblks
> > over an physical address range.
> [..]
> > diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
> > index 2aadb2019b4f..152398bdecc4 100644
> > --- a/arch/x86/mm/numa.c
> > +++ b/arch/x86/mm/numa.c
> [..]
> > +int __init numa_fill_memblks(u64 start, u64 end)
> > +{
> > +	struct numa_memblk **blk = &numa_memblk_list[0];
> > +	struct numa_meminfo *mi = &numa_meminfo;
> > +	int count = 0;
> > +	u64 prev_end;
> > +
> > +	/*
> > +	 * Create a list of pointers to numa_meminfo memblks that
> > +	 * overlap start, end. Exclude (start == bi->end) since
> > +	 * end addresses in both a CFMWS range and a memblk range
> > +	 * are exclusive.
> > +	 *
> > +	 * This list of pointers is used to make in-place changes
> > +	 * that fill out the numa_meminfo memblks.
> > +	 */
> > +	for (int i = 0; i < mi->nr_blks; i++) {
> > +		struct numa_memblk *bi = &mi->blk[i];
> > +
> > +		if (start < bi->end && end >= bi->start) {
> > +			blk[count] = &mi->blk[i];
> > +			count++;
> > +		}
> > +	}
> > +	if (!count)
> > +		return NUMA_NO_MEMBLK;
> > +
> > +	/* Sort the list of pointers in memblk->start order */
> > +	sort(&blk[0], count, sizeof(blk[0]), cmp_memblk, NULL);
> > +
> > +	/* Make sure the first/last memblks include start/end */
> > +	blk[0]->start = min(blk[0]->start, start);
> > +	blk[count - 1]->end = max(blk[count - 1]->end, end);
> > +
> > +	/*
> > +	 * Fill any gaps by tracking the previous memblks
> > +	 * end address and backfilling to it if needed.
> > +	 */
> > +	prev_end = blk[0]->end;
> > +	for (int i = 1; i < count; i++) {
> > +		struct numa_memblk *curr = blk[i];
> > +
> > +		if (prev_end >= curr->start) {
> > +			if (prev_end < curr->end)
> > +				prev_end = curr->end;
> > +		} else {
> > +			curr->start = prev_end;
> > +			prev_end = curr->end;
> > +		}
> > +	}
> > +	return 0;
> > +}
> > +EXPORT_SYMBOL_GPL(numa_fill_memblks);
> 
> After deleting this export you can add:

Drats! Sorry for missing that.
> 
> Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx>