Re: [RESEND][PATCH v3] mm: Use aligned zone start for pfn_to_bitidx calculation

2013-01-09 Thread Laura Abbott
On 1/7/2013 2:31 PM, Andrew Morton wrote: On Sat, 5 Jan 2013 11:28:31 -0800 Laura Abbott wrote: The current calculation in pfn_to_bitidx assumes that (pfn - zone->zone_start_pfn) >> pageblock_order will return the same bit for all pfn in a pageblock. If zone_start_pfn is not aligned to pagebl

Re: [RESEND][PATCH v3] mm: Use aligned zone start for pfn_to_bitidx calculation

2013-01-07 Thread Andrew Morton
On Sat, 5 Jan 2013 11:28:31 -0800 Laura Abbott wrote: > The current calculation in pfn_to_bitidx assumes that > (pfn - zone->zone_start_pfn) >> pageblock_order will return the > same bit for all pfn in a pageblock. If zone_start_pfn is not > aligned to pageblock_nr_pages, this may not always be

[RESEND][PATCH v3] mm: Use aligned zone start for pfn_to_bitidx calculation

2013-01-05 Thread Laura Abbott
The current calculation in pfn_to_bitidx assumes that (pfn - zone->zone_start_pfn) >> pageblock_order will return the same bit for all pfn in a pageblock. If zone_start_pfn is not aligned to pageblock_nr_pages, this may not always be correct. Consider the following with pageblock order = 10, zone