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

From: Pavel Machek
Date: Sat Jul 30 2005 - 08:35:17 EST


From: Michal Schmidt <xschmi00@xxxxxxxxxxxxxxxxxx>

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.

Note that this was even proved correct ;-).

Signed-off-by: Michal Schmidt <xschmi00@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Pavel Machek <pavel@xxxxxxx>

---
commit 06695555bdbe1a5ac3b7926867abfdc9e560121f
tree 3be140250bf556a51261ea75b908906e64182ec3
parent 42b960c2ed61b623d5e84b67f95c7f0ddad0565f
author <pavel@amd.(none)> Sat, 30 Jul 2005 15:19:56 +0200
committer <pavel@amd.(none)> Sat, 30 Jul 2005 15:19:56 +0200

kernel/power/swsusp.c | 13 +------------
1 files changed, 1 insertions(+), 12 deletions(-)

diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c
--- a/kernel/power/swsusp.c
+++ b/kernel/power/swsusp.c
@@ -591,18 +591,7 @@ 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);
}

/**

--
teflon -- maybe it is a trademark, but it should not be.
-
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