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

Commit 41546c17 authored by Johannes Weiner's avatar Johannes Weiner Committed by Linus Torvalds
Browse files

bootmem: clean up free_all_bootmem_core 



Rewrite the code in a more concise way using less variables.

[akpm@linux-foundation.org: fix printk warnings]
Signed-off-by: default avatarJohannes Weiner <hannes@saeurebad.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 636cc40c

mm/bootmem.c

+38 −45
Original line number Diff line number Diff line
@@ -144,66 +144,59 @@ unsigned long __init init_bootmem(unsigned long start, unsigned long pages) 


static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata)

{

	int aligned;

	struct page *page;

	unsigned long pfn;

	unsigned long i, count;

	unsigned long idx, pages;

	unsigned long *map;

	int gofast = 0;



	BUG_ON(!bdata->node_bootmem_map);



	count = 0;

	/* first extant page of the node */

	pfn = PFN_DOWN(bdata->node_boot_start);

	idx = bdata->node_low_pfn - pfn;

	map = bdata->node_bootmem_map;

	unsigned long start, end, pages, count = 0;



	if (!bdata->node_bootmem_map)

		return 0;



	start = PFN_DOWN(bdata->node_boot_start);

	end = bdata->node_low_pfn;



	/*

	 * Check if we are aligned to BITS_PER_LONG pages.  If so, we might

	 * be able to free page orders of that size at once.

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

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

	 */

	if (!(pfn & (BITS_PER_LONG-1)))

		gofast = 1;

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



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

		bdata - bootmem_node_data, start, end, aligned);



	for (i = 0; i < idx; ) {

		unsigned long v = ~map[i / BITS_PER_LONG];

	while (start < end) {

		unsigned long *map, idx, vec;



		map = bdata->node_bootmem_map;

		idx = start - PFN_DOWN(bdata->node_boot_start);

		vec = ~map[idx / BITS_PER_LONG];



		if (gofast && v == ~0UL) {

			int order;

		if (aligned && vec == ~0UL && start + BITS_PER_LONG < end) {

			int order = ilog2(BITS_PER_LONG);



			page = pfn_to_page(pfn);

			__free_pages_bootmem(pfn_to_page(start), order);

			count += BITS_PER_LONG;

			order = ffs(BITS_PER_LONG) - 1;

			__free_pages_bootmem(page, order);

			i += BITS_PER_LONG;

			page += BITS_PER_LONG;

		} else if (v) {

			unsigned long m;



			page = pfn_to_page(pfn);

			for (m = 1; m && i < idx; m<<=1, page++, i++) {

				if (v & m) {

					count++;

		} else {

			unsigned long off = 0;



			while (vec && off < BITS_PER_LONG) {

				if (vec & 1) {

					page = pfn_to_page(start + off);

					__free_pages_bootmem(page, 0);

					count++;

				}

				vec >>= 1;

				off++;

			}

		} else {

			i += BITS_PER_LONG;

		}

		pfn += BITS_PER_LONG;

		start += BITS_PER_LONG;

	}



	/*

	 * Now free the allocator bitmap itself, it's not

	 * needed anymore:

	 */

	page = virt_to_page(bdata->node_bootmem_map);

	pages = bdata->node_low_pfn - PFN_DOWN(bdata->node_boot_start);

	idx = bootmem_bootmap_pages(pages);

	for (i = 0; i < idx; i++, page++)

		__free_pages_bootmem(page, 0);

	count += i;

	bdata->node_bootmem_map = NULL;

	pages = bootmem_bootmap_pages(pages);

	count += pages;

	while (pages--)

		__free_pages_bootmem(page++, 0);



	bdebug("nid=%td released=%lx\n", bdata - bootmem_node_data, count);