Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 799f933a authored by Johannes Weiner's avatar Johannes Weiner Committed by Linus Torvalds
Browse files

mm: bootmem: try harder to free pages in bulk 



The loop that frees pages to the page allocator while bootstrapping tries
to free higher-order blocks only when the starting address is aligned to
that block size.  Otherwise it will free all pages on that node
one-by-one.

Change it to free individual pages up to the first aligned block and then
try higher-order frees from there.

Signed-off-by: default avatarJohannes Weiner <hannes@cmpxchg.org>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 560a036b

mm/bootmem.c

+10 −12
Original line number Diff line number Diff line
@@ -171,7 +171,6 @@ void __init free_bootmem_late(unsigned long addr, unsigned long size) 


static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)

{

	int aligned;

	struct page *page;

	unsigned long start, end, pages, count = 0;
@@ -181,14 +180,8 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata) 
	start = bdata->node_min_pfn;

	end = bdata->node_low_pfn;



	/*

	 * If the start is aligned to the machines wordsize, we might

	 * be able to free pages in bulks of that order.

	 */

	aligned = !(start & (BITS_PER_LONG - 1));



	bdebug("nid=%td start=%lx end=%lx aligned=%d\n",

		bdata - bootmem_node_data, start, end, aligned);

	bdebug("nid=%td start=%lx end=%lx\n",

		bdata - bootmem_node_data, start, end);



	while (start < end) {

		unsigned long *map, idx, vec;
@@ -196,12 +189,17 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata) 
		map = bdata->node_bootmem_map;

		idx = start - bdata->node_min_pfn;

		vec = ~map[idx / BITS_PER_LONG];



		if (aligned && vec == ~0UL) {

		/*

		 * If we have a properly aligned and fully unreserved

		 * BITS_PER_LONG block of pages in front of us, free

		 * it in one go.

		 */

		if (IS_ALIGNED(start, BITS_PER_LONG) && vec == ~0UL) {

			int order = ilog2(BITS_PER_LONG);



			__free_pages_bootmem(pfn_to_page(start), order);

			count += BITS_PER_LONG;

			start += BITS_PER_LONG;

		} else {

			unsigned long off = 0;
@@ -214,8 +212,8 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata) 
				vec >>= 1;

				off++;

			}

			start = ALIGN(start + 1, BITS_PER_LONG);

		}

		start += BITS_PER_LONG;

	}



	page = virt_to_page(bdata->node_bootmem_map);