Commit aee35e4b authored by Qu Wenruo's avatar Qu Wenruo Committed by David Sterba
Browse files

btrfs: raid56: avoid double for loop inside alloc_rbio_essential_pages() 



The double loop is just checking if the page for the vertical stripe
is allocated.

We can easily convert it to single loop and get rid of @stripe variable.

Signed-off-by: default avatarQu Wenruo <wqu@suse.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent ef340fcc

fs/btrfs/raid56.c

+14 −15
Original line number Diff line number Diff line
@@ -2380,24 +2380,23 @@ void raid56_add_scrub_pages(struct btrfs_raid_bio *rbio, struct page *page, 
static int alloc_rbio_essential_pages(struct btrfs_raid_bio *rbio)

{

	const u32 sectorsize = rbio->bioc->fs_info->sectorsize;

	int stripe;

	int sectornr;

	int total_sector_nr;



	for_each_set_bit(sectornr, &rbio->dbitmap, rbio->stripe_nsectors) {

		for (stripe = 0; stripe < rbio->real_stripes; stripe++) {

	for (total_sector_nr = 0; total_sector_nr < rbio->nr_sectors;

	     total_sector_nr++) {

		struct page *page;

			int index = (stripe * rbio->stripe_nsectors + sectornr) *

				    sectorsize >> PAGE_SHIFT;

		int sectornr = total_sector_nr % rbio->stripe_nsectors;

		int index = (total_sector_nr * sectorsize) >> PAGE_SHIFT;



		if (!test_bit(sectornr, &rbio->dbitmap))

			continue;

		if (rbio->stripe_pages[index])

			continue;



		page = alloc_page(GFP_NOFS);

		if (!page)

			return -ENOMEM;

		rbio->stripe_pages[index] = page;

	}

	}

	index_stripe_sectors(rbio);

	return 0;

}