From 537632e0a54a5355cdd0330911d18c3b773f9cf7 Mon Sep 17 00:00:00 2001
From: Boaz Harrosh <bharrosh@panasas.com>
Date: Wed, 11 Jul 2012 15:27:13 +0300
Subject: ore: Unlock r4w pages in exact reverse order of locking
The read-4-write pages are locked in address ascending order.
But where unlocked in a way easiest for coding. Fix that,
locks should be released in opposite order of locking, .i.e
descending address order.
I have not hit this dead-lock. It was found by inspecting the
dbug print-outs. I suspect there is an higher lock at caller that
protects us, but fix it regardless.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
---
fs/exofs/ore_raid.c | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)
(limited to 'fs/exofs')
diff --git a/fs/exofs/ore_raid.c b/fs/exofs/ore_raid.c
index fff2070c6751..5f376d14fdcc 100644
--- a/fs/exofs/ore_raid.c
+++ b/fs/exofs/ore_raid.c
@@ -144,26 +144,26 @@ static void _sp2d_reset(struct __stripe_pages_2d *sp2d,
{
unsigned data_devs = sp2d->data_devs;
unsigned group_width = data_devs + sp2d->parity;
- unsigned p;
+ int p, c;
if (!sp2d->needed)
return;
- for (p = 0; p < sp2d->pages_in_unit; p++) {
- struct __1_page_stripe *_1ps = &sp2d->_1p_stripes[p];
-
- if (_1ps->write_count < group_width) {
- unsigned c;
+ for (c = data_devs - 1; c >= 0; --c)
+ for (p = sp2d->pages_in_unit - 1; p >= 0; --p) {
+ struct __1_page_stripe *_1ps = &sp2d->_1p_stripes[p];
- for (c = 0; c < data_devs; c++)
- if (_1ps->page_is_read[c]) {
- struct page *page = _1ps->pages[c];
+ if (_1ps->page_is_read[c]) {
+ struct page *page = _1ps->pages[c];
- r4w->put_page(priv, page);
- _1ps->page_is_read[c] = false;
- }
+ r4w->put_page(priv, page);
+ _1ps->page_is_read[c] = false;
+ }
}
+ for (p = 0; p < sp2d->pages_in_unit; p++) {
+ struct __1_page_stripe *_1ps = &sp2d->_1p_stripes[p];
+
memset(_1ps->pages, 0, group_width * sizeof(*_1ps->pages));
_1ps->write_count = 0;
_1ps->tx = NULL;
--
cgit