Attachment 576087 Details for Bug 785384 – Better watermark the number of pages used by hibernation I/O

[patch] Better watermark the number of pages used by hibernation I/O

hibernate-pages-watermark.patch (text/plain), 4.22 KB, created by Bojan Smojver on 2012-04-08 23:15:26 UTC

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Creator: Bojan Smojver

Created: 2012-04-08 23:15:26 UTC

Size: 4.22 KB

patch

obsolete

> kernel/power/swap.c |   46 ++++++++++++++++++++++++++++++++--------------
> 1 files changed, 32 insertions(+), 14 deletions(-)
>
>diff --git a/kernel/power/swap.c b/kernel/power/swap.c
>index 8742fd0..21314b4 100644
>--- a/kernel/power/swap.c
>+++ b/kernel/power/swap.c
>@@ -6,7 +6,7 @@
>  *
>  * Copyright (C) 1998,2001-2005 Pavel Machek <pavel@ucw.cz>
>  * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
>- * Copyright (C) 2010 Bojan Smojver <bojan@rexursive.com>
>+ * Copyright (C) 2010-2012 Bojan Smojver <bojan@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;
> };
> 
>@@ -265,14 +274,17 @@ static int write_page(void *buf, sector_t offset, struct bio **bio_chain)
> 		return -ENOSPC;
> 
> 	if (bio_chain) {
>-		src = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
>+		src = (void *)__get_free_page(__GFP_WAIT | __GFP_NOWARN |
>+		                              __GFP_NORETRY);
> 		if (src) {
> 			copy_page(src, buf);
> 		} else {
> 			ret = hib_wait_on_bio_chain(bio_chain); /* Free pages */
> 			if (ret)
> 				return ret;
>-			src = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
>+			src = (void *)__get_free_page(__GFP_WAIT |
>+			                              __GFP_NOWARN |
>+			                              __GFP_NORETRY);
> 			if (src) {
> 				copy_page(src, buf);
> 			} else {
>@@ -316,8 +328,7 @@ 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 +363,15 @@ 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 +419,7 @@ 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 +630,10 @@ 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.
>@@ -1129,14 +1144,17 @@ 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++) {
> 		page[i] = (void *)__get_free_page(i < LZO_CMP_PAGES ?
> 		                                  __GFP_WAIT | __GFP_HIGH :
>-		                                  __GFP_WAIT);
>+		                                  __GFP_WAIT | __GFP_NOWARN |
>+		                                  __GFP_NORETRY);
>+
> 		if (!page[i]) {
> 			if (i < LZO_CMP_PAGES) {
> 				ring_size = i;

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Attachments on bug 785384: 569728 | 570742 | 571226 | 572081 | 572093 | 572114 | 573466 | 573467 | 573507 | 574743 | 575923 | 576087 | 576205 | 576257 | 576266 | 576333