[PATCH] swsusp: simpler calculation of number of pages in PBE list

From: Michal Schmidt
Date: Fri Jul 29 2005 - 14:52:52 EST


The function calc_nr uses an iterative algorithm to calculate the number of pages needed for the image and the pagedir. Exactly the same result can be obtained with a one-line expression.

Signed-off-by: Michal Schmidt <xschmi00@xxxxxxxxxxxxxxxxxx> diff -Nurp -X dontdiff.new linux-mm/kernel/power/swsusp.c linux-mm.mich/kernel/power/swsusp.c
--- linux-mm/kernel/power/swsusp.c 2005-07-28 13:57:53.000000000 +0200
+++ linux-mm.mich/kernel/power/swsusp.c 2005-07-29 21:01:46.000000000 +0200
@@ -737,18 +737,7 @@ static void copy_data_pages(void)

static int calc_nr(int nr_copy)
{
- int extra = 0;
- int mod = !!(nr_copy % PBES_PER_PAGE);
- int diff = (nr_copy / PBES_PER_PAGE) + mod;
-
- do {
- extra += diff;
- nr_copy += diff;
- mod = !!(nr_copy % PBES_PER_PAGE);
- diff = (nr_copy / PBES_PER_PAGE) + mod - extra;
- } while (diff > 0);
-
- return nr_copy;
+ return nr_copy + (nr_copy+PBES_PER_PAGE-2)/(PBES_PER_PAGE-1);
}

/**