linux-stable.git/include/linux/swap.h, branch linux-2.6.24.y

oom: move prototypes to appropriate header file

2007-10-17T15:42:45+00:00

Move the OOM killer's extern function prototypes to include/linux/oom.h and
include it where necessary.

[clg@fr.ibm.com: build fix]
Cc: Andrea Arcangeli 
Acked-by: Christoph Lameter 
Signed-off-by: David Rientjes 
Signed-off-by: Cedric Le Goater 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Drop 'size' argument from bio_endio and bi_end_io

2007-10-10T07:25:57+00:00

As bi_end_io is only called once when the reqeust is complete,
the 'size' argument is now redundant.  Remove it.

Now there is no need for bio_endio to subtract the size completed
from bi_size.  So don't do that either.

While we are at it, change bi_end_io to return void.

Signed-off-by: Neil Brown 
Signed-off-by: Jens Axboe

Lumpy Reclaim V4

2007-07-17T17:22:59+00:00

When we are out of memory of a suitable size we enter reclaim.  The current
reclaim algorithm targets pages in LRU order, which is great for fairness at
order-0 but highly unsuitable if you desire pages at higher orders.  To get
pages of higher order we must shoot down a very high proportion of memory;
>95% in a lot of cases.

This patch set adds a lumpy reclaim algorithm to the allocator.  It targets
groups of pages at the specified order anchored at the end of the active and
inactive lists.  This encourages groups of pages at the requested orders to
move from active to inactive, and active to free lists.  This behaviour is
only triggered out of direct reclaim when higher order pages have been
requested.

This patch set is particularly effective when utilised with an
anti-fragmentation scheme which groups pages of similar reclaimability
together.

This patch set is based on Peter Zijlstra's lumpy reclaim V2 patch which forms
the foundation.  Credit to Mel Gorman for sanitity checking.

Mel said:

  The patches have an application with hugepage pool resizing.

  When lumpy-reclaim is used used with ZONE_MOVABLE, the hugepages pool can
  be resized with greater reliability.  Testing on a desktop machine with 2GB
  of RAM showed that growing the hugepage pool with ZONE_MOVABLE on it's own
  was very slow as the success rate was quite low.  Without lumpy-reclaim,
  each attempt to grow the pool by 100 pages would yield 1 or 2 hugepages.
  With lumpy-reclaim, getting 40 to 70 hugepages on each attempt was typical.

[akpm@osdl.org: ia64 pfn_to_nid fixes and loop cleanup]
[bunk@stusta.de: static declarations for internal functions]
[a.p.zijlstra@chello.nl: initial lumpy V2 implementation]
Signed-off-by: Andy Whitcroft 
Acked-by: Peter Zijlstra 
Acked-by: Mel Gorman 
Acked-by: Mel Gorman 
Cc: Bob Picco 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] Drop nr_free_pages_pgdat()

2007-02-11T18:51:18+00:00

Function is unnecessary now.  We can use the summing features of the ZVCs to
get the values we need.

Signed-off-by: Christoph Lameter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] Drop free_pages()

2007-02-11T18:51:18+00:00

nr_free_pages is now a simple access to a global variable.  Make it a macro
instead of a function.

The nr_free_pages now requires vmstat.h to be included.  There is one
occurrence in power management where we need to add the include.  Directly
refrer to global_page_state() there to clarify why the #include was added.

[akpm@osdl.org: arm build fix]
[akpm@osdl.org: sparc64 build fix]
Signed-off-by: Christoph Lameter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] swsusp: Do not fail if resume device is not set

2007-01-06T07:55:22+00:00

In the kernels later than 2.6.19 there is a regression that makes swsusp
fail if the resume device is not explicitly specified.

It can be fixed by adding an additional parameter to
mm/swapfile.c:swap_type_of() allowing us to pass the (struct block_device
*) corresponding to the first available swap back to the caller.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Pavel Machek 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] swsusp: use block device offsets to identify swap locations

2006-12-07T16:39:27+00:00

Make swsusp use block device offsets instead of swap offsets to identify swap
locations and make it use the same code paths for writing as well as for
reading data.

This allows us to use the same code for handling swap files and swap
partitions and to simplify the code, eg.  by dropping rw_swap_page_sync().

Signed-off-by: Rafael J. Wysocki 
Cc: Pavel Machek 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] swsusp: use partition device and offset to identify swap areas

2006-12-07T16:39:27+00:00

The Linux kernel handles swap files almost in the same way as it handles swap
partitions and there are only two differences between these two types of swap
areas:

(1) swap files need not be contiguous,

(2) the header of a swap file is not in the first block of the partition
    that holds it.  From the swsusp's point of view (1) is not a problem,
    because it is already taken care of by the swap-handling code, but (2) has
    to be taken into consideration.

In principle the location of a swap file's header may be determined with the
help of appropriate filesystem driver.  Unfortunately, however, it requires
the filesystem holding the swap file to be mounted, and if this filesystem is
journaled, it cannot be mounted during a resume from disk.  For this reason we
need some other means by which swap areas can be identified.

For example, to identify a swap area we can use the partition that holds the
area and the offset from the beginning of this partition at which the swap
header is located.

The following patch allows swsusp to identify swap areas this way.  It changes
swap_type_of() so that it takes an additional argument representing an offset
of the swap header within the partition represented by its first argument.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Pavel Machek 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] new scheme to preempt swap token

2006-12-07T16:39:21+00:00

The new swap token patches replace the current token traversal algo.  The old
algo had a crude timeout parameter that was used to handover the token from
one task to another.  This algo, transfers the token to the tasks that are in
need of the token.  The urgency for the token is based on the number of times
a task is required to swap-in pages.  Accordingly, the priority of a task is
incremented if it has been badly affected due to swap-outs.  To ensure that
the token doesnt bounce around rapidly, the token holders are given a priority
boost.  The priority of tasks is also decremented, if their rate of swap-in's
keeps reducing.  This way, the condition to check whether to pre-empt the swap
token, is a matter of comparing two task's priority fields.

[akpm@osdl.org: cleanups]
Signed-off-by: Ashwin Chaugule 
Cc: Rik van Riel 
Cc: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] swsusp: read speedup

2006-09-26T15:48:58+00:00

Implement async reads for swsusp resuming.

Crufty old PIII testbox:
	15.7 MB/s -> 20.3 MB/s

Sony Vaio:
	14.6 MB/s -> 33.3 MB/s

I didn't implement the post-resume bio_set_pages_dirty().  I don't really
understand why resume needs to run set_page_dirty() against these pages.

It might be a worry that this code modifies PG_Uptodate, PG_Error and
PG_Locked against the image pages.  Can this possibly affect the resumed-into
kernel?  Hopefully not, if we're atomically restoring its mem_map?

Cc: Pavel Machek 
Cc: "Rafael J. Wysocki" 
Cc: Jens Axboe 
Cc: Laurent Riffard 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds