On Thu, 2018-11-01 at 08:17 +0200, Mike Rapoport wrote: > On Wed, Oct 31, 2018 at 03:40:02PM +0000, Pasha Tatashin wrote: > > > > > > On 10/17/18 7:54 PM, Alexander Duyck wrote: > > > This patch introduces a new iterator for_each_free_mem_pfn_range_in_zone. > > > > > > This iterator will take care of making sure a given memory range provided > > > is in fact contained within a zone. It takes are of all the bounds checking > > > we were doing in deferred_grow_zone, and deferred_init_memmap. In addition > > > it should help to speed up the search a bit by iterating until the end of a > > > range is greater than the start of the zone pfn range, and will exit > > > completely if the start is beyond the end of the zone. > > > > > > This patch adds yet another iterator called > > > for_each_free_mem_range_in_zone_from and then uses it to support > > > initializing and freeing pages in groups no larger than MAX_ORDER_NR_PAGES. > > > By doing this we can greatly improve the cache locality of the pages while > > > we do several loops over them in the init and freeing process. > > > > > > We are able to tighten the loops as a result since we only really need the > > > checks for first_init_pfn in our first iteration and after that we can > > > assume that all future values will be greater than this. So I have added a > > > function called deferred_init_mem_pfn_range_in_zone that primes the > > > iterators and if it fails we can just exit. > > > > > > On my x86_64 test system with 384GB of memory per node I saw a reduction in > > > initialization time from 1.85s to 1.38s as a result of this patch. > > > > > > Signed-off-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxxxxxxxx> > > > [ ... ] > > > > --- > > > include/linux/memblock.h | 58 +++++++++++++++ > > > mm/memblock.c | 63 ++++++++++++++++ > > > mm/page_alloc.c | 176 ++++++++++++++++++++++++++++++++-------------- > > > 3 files changed, 242 insertions(+), 55 deletions(-) > > > > > > diff --git a/include/linux/memblock.h b/include/linux/memblock.h > > > index aee299a6aa76..2ddd1bafdd03 100644 > > > --- a/include/linux/memblock.h > > > +++ b/include/linux/memblock.h > > > @@ -178,6 +178,25 @@ void __next_reserved_mem_region(u64 *idx, phys_addr_t *out_start, > > > p_start, p_end, p_nid)) > > > > > > /** > > > + * for_each_mem_range_from - iterate through memblock areas from type_a and not > > > + * included in type_b. Or just type_a if type_b is NULL. > > > + * @i: u64 used as loop variable > > > + * @type_a: ptr to memblock_type to iterate > > > + * @type_b: ptr to memblock_type which excludes from the iteration > > > + * @nid: node selector, %NUMA_NO_NODE for all nodes > > > + * @flags: pick from blocks based on memory attributes > > > + * @p_start: ptr to phys_addr_t for start address of the range, can be %NULL > > > + * @p_end: ptr to phys_addr_t for end address of the range, can be %NULL > > > + * @p_nid: ptr to int for nid of the range, can be %NULL > > > + */ > > > +#define for_each_mem_range_from(i, type_a, type_b, nid, flags, \ > > > + p_start, p_end, p_nid) \ > > > + for (i = 0, __next_mem_range(&i, nid, flags, type_a, type_b, \ > > > + p_start, p_end, p_nid); \ > > > + i != (u64)ULLONG_MAX; \ > > > + __next_mem_range(&i, nid, flags, type_a, type_b, \ > > > + p_start, p_end, p_nid)) > > > +/** > > > * for_each_mem_range_rev - reverse iterate through memblock areas from > > > * type_a and not included in type_b. Or just type_a if type_b is NULL. > > > * @i: u64 used as loop variable > > > @@ -248,6 +267,45 @@ void __next_mem_pfn_range(int *idx, int nid, unsigned long *out_start_pfn, > > > i >= 0; __next_mem_pfn_range(&i, nid, p_start, p_end, p_nid)) > > > #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ > > > > > > +#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT > > Sorry for jumping late, but I've noticed this only now. > Do the new iterators have to be restricted by > CONFIG_DEFERRED_STRUCT_PAGE_INIT? They don't have to be. I just wrapped them since I figured it is better to just strip the code if it isn't going to be used rather then leave it floating around taking up space. Thanks. - Alex
