On 2012-04-05 12:53, Jonathan Nieder wrote:
> Per Olofsson wrote:
>
>> > I can confirm that the proposed patch[1] fixes the issue for me.
>> >
>> > [1] http://thread.gmane.org/gmane.linux.kernel/1273425
> Thanks! The patch mentioned above is v7. I'm attaching v8, which
> based on the upstream report I assume you have also already tested.
AFAICT they are identical. But maybe I'm missing some small detail.
The patch I tested is the one attached at Redhat's bugzilla:
https://bugzilla.redhat.com/show_bug.cgi?id=785384
I'm attaching it to this mail as well for reference.
--
Pelle
kernel/power/swap.c | 35 ++++++++++++++++++++++++-----------
1 files changed, 24 insertions(+), 11 deletions(-)
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 8742fd0..26d304b 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -6,7 +6,7 @@
*
* Copyright (C) 1998,2001-2005 Pavel Machek <pa...@ucw.cz>
* Copyright (C) 2006 Rafael J. Wysocki <r...@sisk.pl>
- * Copyright (C) 2010 Bojan Smojver <bo...@rexursive.com>
+ * Copyright (C) 2010-2012 Bojan Smojver <bo...@rexursive.com>
*
* This file is released under the GPLv2.
*
@@ -51,6 +51,15 @@
#define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1)
+/*
+ * Number of pages required to be kept free while writing the image. Always
+ * three quarters of all available pages before the writing starts.
+ */
+static inline unsigned long reqd_free_pages(void)
+{
+ return (nr_free_pages() / 4) * 3;
+}
+
struct swap_map_page {
sector_t entries[MAP_PAGE_ENTRIES];
sector_t next_swap;
@@ -72,7 +81,7 @@ struct swap_map_handle {
sector_t cur_swap;
sector_t first_sector;
unsigned int k;
- unsigned long nr_free_pages, written;
+ unsigned long reqd_free_pages;
u32 crc32;
};
@@ -316,8 +325,7 @@ static int get_swap_writer(struct swap_map_handle *handle)
goto err_rel;
}
handle->k = 0;
- handle->nr_free_pages = nr_free_pages() >> 1;
- handle->written = 0;
+ handle->reqd_free_pages = reqd_free_pages();
handle->first_sector = handle->cur_swap;
return 0;
err_rel:
@@ -352,11 +360,15 @@ static int swap_write_page(struct swap_map_handle *handle, void *buf,
handle->cur_swap = offset;
handle->k = 0;
}
- if (bio_chain && ++handle->written > handle->nr_free_pages) {
+ if (bio_chain && nr_free_pages() <= handle->reqd_free_pages) {
error = hib_wait_on_bio_chain(bio_chain);
if (error)
goto out;
- handle->written = 0;
+ /*
+ * Recalculate the number of required free pages, to make sure
+ * we never take more than a quarter.
+ */
+ handle->reqd_free_pages = reqd_free_pages();
}
out:
return error;
@@ -404,7 +416,7 @@ static int swap_writer_finish(struct swap_map_handle *handle,
#define LZO_THREADS 3
/* Maximum number of pages for read buffering. */
-#define LZO_READ_PAGES (MAP_PAGE_ENTRIES * 8)
+#define LZO_READ_PAGES 8192
/**
@@ -615,10 +627,10 @@ static int save_image_lzo(struct swap_map_handle *handle,
}
/*
- * Adjust number of free pages after all allocations have been done.
- * We don't want to run out of pages when writing.
+ * Adjust the number of required free pages after all allocations have
+ * been done. We don't want to run out of pages when writing.
*/
- handle->nr_free_pages = nr_free_pages() >> 1;
+ handle->reqd_free_pages = reqd_free_pages();
/*
* Start the CRC32 thread.
@@ -1129,8 +1141,9 @@ static int load_image_lzo(struct swap_map_handle *handle,
/*
* Adjust number of pages for read buffering, in case we are short.
+ * Never take more than a quarter of all available pages.
*/
- read_pages = (nr_free_pages() - snapshot_get_image_size()) >> 1;
+ read_pages = (nr_free_pages() - snapshot_get_image_size()) / 4;
read_pages = clamp_val(read_pages, LZO_CMP_PAGES, LZO_READ_PAGES);
for (i = 0; i < read_pages; i++) {
