Commit Graph

39 Commits

Author SHA1 Message Date
Randy Dunlap 9f1583339a [PATCH] use add_taint() for setting tainted bit flags
Use the add_taint() interface for setting tainted bit flags instead of
doing it manually.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-13 08:22:29 -07:00
Renaud Lienhart 207f36eec9 [PATCH] remove invalid comment in mm/page_alloc.c
free_pages_bulk() doesn't free the entire list if count == 0.

Signed-off-by: Renaud Lienhart <renaud.lienhart@free.fr>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-10 10:06:31 -07:00
Paul Jackson 9bf2229f88 [PATCH] cpusets: formalize intermediate GFP_KERNEL containment
This patch makes use of the previously underutilized cpuset flag
'mem_exclusive' to provide what amounts to another layer of memory placement
resolution.  With this patch, there are now the following four layers of
memory placement available:

 1) The whole system (interrupt and GFP_ATOMIC allocations can use this),
 2) The nearest enclosing mem_exclusive cpuset (GFP_KERNEL allocations can use),
 3) The current tasks cpuset (GFP_USER allocations constrained to here), and
 4) Specific node placement, using mbind and set_mempolicy.

These nest - each layer is a subset (same or within) of the previous.

Layer (2) above is new, with this patch.  The call used to check whether a
zone (its node, actually) is in a cpuset (in its mems_allowed, actually) is
extended to take a gfp_mask argument, and its logic is extended, in the case
that __GFP_HARDWALL is not set in the flag bits, to look up the cpuset
hierarchy for the nearest enclosing mem_exclusive cpuset, to determine if
placement is allowed.  The definition of GFP_USER, which used to be identical
to GFP_KERNEL, is changed to also set the __GFP_HARDWALL bit, in the previous
cpuset_gfp_hardwall_flag patch.

GFP_ATOMIC and GFP_KERNEL allocations will stay within the current tasks
cpuset, so long as any node therein is not too tight on memory, but will
escape to the larger layer, if need be.

The intended use is to allow something like a batch manager to handle several
jobs, each job in its own cpuset, but using common kernel memory for caches
and such.  Swapper and oom_kill activity is also constrained to Layer (2).  A
task in or below one mem_exclusive cpuset should not cause swapping on nodes
in another non-overlapping mem_exclusive cpuset, nor provoke oom_killing of a
task in another such cpuset.  Heavy use of kernel memory for i/o caching and
such by one job should not impact the memory available to jobs in other
non-overlapping mem_exclusive cpusets.

This patch enables providing hardwall, inescapable cpusets for memory
allocations of each job, while sharing kernel memory allocations between
several jobs, in an enclosing mem_exclusive cpuset.

Like Dinakar's patch earlier to enable administering sched domains using the
cpu_exclusive flag, this patch also provides a useful meaning to a cpuset flag
that had previously done nothing much useful other than restrict what cpuset
configurations were allowed.

Signed-off-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:40 -07:00
Ravikiran G Thirumalai 6c231b7bab [PATCH] Additions to .data.read_mostly section
Mark variables which are usually accessed for reads with __readmostly.

Signed-off-by: Alok N Kataria <alokk@calsoftinc.com>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:33 -07:00
Christoph Lameter c3d8c14145 [PATCH] More __read_mostly variables
Move some more frequently read variables that showed up during some of our
performance tests as sometimes ending up in hot cachelines to the
read_mostly section.

Fix: Move the __read_mostly from before hpet_usec_quotient to follow the
variable like the other uses of __read_mostly.

Signed-off-by: Alok N Kataria <alokk@calsoftinc.com>
Signed-off-by: Christoph Lameter <christoph@scalex86.org>
Signed-off-by: Shai Fultheim <shai@scalex86.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 16:57:18 -07:00
Martin Hicks c07e02db76 [PATCH] VM: add page_state info to per-node meminfo
Add page_state info to the per-node meminfo file in sysfs.  This is mostly
just for informational purposes.

The lack of this information was brought up recently during a discussion
regarding pagecache clearing, and I put this patch together to test out one
of the suggestions.

It seems like interesting info to have, so I'm submitting the patch.

Signed-off-by: Martin Hicks <mort@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:05:49 -07:00
Martin Hicks 53e9a6159f [PATCH] VM: zone reclaim atomic ops cleanup
Christoph Lameter and Marcelo Tosatti asked to get rid of the
atomic_inc_and_test() to cleanup the atomic ops in the zone reclaim code.

Signed-off-by: Martin Hicks <mort@sgi.com>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:05:44 -07:00
Nick Piggin 242e546862 [PATCH] mm: remove atomic
This bitop does not need to be atomic because it is performed when there will
be no references to the page (ie.  the page is being freed).

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:05:44 -07:00
Martin J. Bligh e310fd4325 [PATCH] Fix NUMA node sizing in nr_free_zone_pages
We are iterating over all nodes in nr_free_zone_pages().  Because the
fallback zonelists contain all nodes in the system, and we walk all the
zonelists, we're counting memory multiple times (once for each node).  This
caused us to make a size estimate of 32GB for an 8GB AMD64 box, which makes
all the dirty ratio calculations, etc incorrect.

There's still a further bug to fix from e820 holes causing overestimation
as well, but this fix is separate, and good as is, and fixes one class of
problems.  Problem found by Badari, and tested by Ram Pai - thanks!

Signed-off-by:  Martin J. Bligh <mbligh@mbligh.org>
Signed-off-by:  Matt Dobson <colpatch@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-30 10:14:46 -07:00
Andy Whitcroft 12b1c5f382 [PATCH] Remove bogus warning in page_alloc.c
Originally __free_pages_bulk used the relative page number within a zone to
define its buddies.  This meant that to maintain the "maximally aligned"
requirements (that an allocation of size N will be aligned at least to N
physically) zones had to also be aligned to 1<<MAX_ORDER pages.  When
__free_pages_bulk was updated to use the relative page frame numbers of the
free'd pages to pair buddies this released the alignment constraint on the
'left' edge of the zone.  This allows _either_ edge of the zone to contain
partial MAX_ORDER sized buddies.  These simply never will have matching
buddies and thus will never make it to the 'top' of the pyramid.

The patch below removes a now redundant check ensuring that the mem_map was
aligned to MAX_ORDER.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Cc: Christoph Lameter <christoph@lameter.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-27 16:25:54 -07:00
Marcelo Tosatti 37b173a4d0 [PATCH] remove completly bogus comment inside __alloc_pages() try_to_free_pages handling
Remove completly bogus comment from did_some_progress != 0 handling (that
same comment is a few lines below on did_some_progress = 0 case, where it
belongs).

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-07 18:23:35 -07:00
Marcelo Tosatti 79b9ce311e [PATCH] print order information when OOM killing
Dump the current allocation order when OOM killing.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-07 18:23:35 -07:00
Bob Picco 3212c6be25 [PATCH] fix WANT_PAGE_VIRTUAL in memmap_init
I spotted this issue while in memmap_init last week.  I can't say the
change has any test coverage by me.  start_pfn was formerly used in main
"for" loop.  The fix is replace start_pfn with pfn.

Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-27 15:11:42 -07:00
Andy Whitcroft 29751f6991 [PATCH] sparsemem hotplug base
Make sparse's initalization be accessible at runtime.  This allows sparse
mappings to be created after boot in a hotplug situation.

This patch is separated from the previous one just to give an indication how
much of the sparse infrastructure is *just* for hotplug memory.

The section_mem_map doesn't really store a pointer.  It stores something that
is convenient to do some math against to get a pointer.  It isn't valid to
just do *section_mem_map, so I don't think it should be stored as a pointer.

There are a couple of things I'd like to store about a section.  First of all,
the fact that it is !NULL does not mean that it is present.  There could be
such a combination where section_mem_map *is* NULL, but the math gets you
properly to a real mem_map.  So, I don't think that check is safe.

Since we're storing 32-bit-aligned structures, we have a few bits in the
bottom of the pointer to play with.  Use one bit to encode whether there's
really a mem_map there, and the other one to tell whether there's a valid
section there.  We need to distinguish between the two because sometimes
there's a gap between when a section is discovered to be present and when we
can get the mem_map for it.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:05 -07:00
Andy Whitcroft 641c767389 [PATCH] sparsemem swiss cheese numa layouts
The part of the sparsemem patch which modifies memmap_init_zone() has recently
become a problem.  It changes behavior so that there is a call to
pfn_to_page() for each individual page inside of a node's range:
node_start_pfn through node_end_pfn.  It used to simply do this once, at the
beginning of the node, but having sparsemem's non-contiguous mem_map[]s inside
of a node made it necessary to change.

Mike Kravetz recently wrote a patch which made the NUMA code accept some new
kinds of layouts.  The system's memory was laid out like this, with node 0's
memory in two pieces: one before and one after node 1's memory:

	Node 0: +++++     +++++
	Node 1:      +++++

Previous behavior before Mike's patch was to assign nodes like this:

	Node 0: 00000     XXXXX
	Node 1:      11111

Where the 'X' areas were simply thrown away.  The new behavior was to make the
pg_data_t span node 0 across all of its areas, including areas that are really
node 1's: Node 0: 000000000000000 Node 1: 11111

This wastes a little bit of mem_map space, but ends up being OK, and more
fully utilizes the system's memory.  memmap_init_zone() initializes all of the
"struct page"s for node 0, even for the "hole", but those never get used,
because there is no pfn_to_page() that resolves to those pages.  However, only
calling pfn_to_page() once, memmap_init_zone() always uses the pages that were
allocated for node0->node_mem_map because:

	struct page *start = pfn_to_page(start_pfn);
	// effectively start = &node->node_mem_map[0]
	for (page = start; page < (start + size); page++) {
		init_page_here();...
		page++;
	}

Slow, and wasteful, but generally harmless.

But, modify that to call pfn_to_page() for each loop iteration (like sparsemem
does):

	for (pfn = start_pfn; pfn < < (start_pfn + size); pfn++++) {
		page = pfn_to_page(pfn);
	}

And you end up trying to initialize node 1's pages too early, along with bogus
data from node 0.  This patch checks for those weird layouts and declines to
touch the pages, making the more frequent pfn_to_page() calls OK to do.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:05 -07:00
Andy Whitcroft d41dee369b [PATCH] sparsemem memory model
Sparsemem abstracts the use of discontiguous mem_maps[].  This kind of
mem_map[] is needed by discontiguous memory machines (like in the old
CONFIG_DISCONTIGMEM case) as well as memory hotplug systems.  Sparsemem
replaces DISCONTIGMEM when enabled, and it is hoped that it can eventually
become a complete replacement.

A significant advantage over DISCONTIGMEM is that it's completely separated
from CONFIG_NUMA.  When producing this patch, it became apparent in that NUMA
and DISCONTIG are often confused.

Another advantage is that sparse doesn't require each NUMA node's ranges to be
contiguous.  It can handle overlapping ranges between nodes with no problems,
where DISCONTIGMEM currently throws away that memory.

Sparsemem uses an array to provide different pfn_to_page() translations for
each SECTION_SIZE area of physical memory.  This is what allows the mem_map[]
to be chopped up.

In order to do quick pfn_to_page() operations, the section number of the page
is encoded in page->flags.  Part of the sparsemem infrastructure enables
sharing of these bits more dynamically (at compile-time) between the
page_zone() and sparsemem operations.  However, on 32-bit architectures, the
number of bits is quite limited, and may require growing the size of the
page->flags type in certain conditions.  Several things might force this to
occur: a decrease in the SECTION_SIZE (if you want to hotplug smaller areas of
memory), an increase in the physical address space, or an increase in the
number of used page->flags.

One thing to note is that, once sparsemem is present, the NUMA node
information no longer needs to be stored in the page->flags.  It might provide
speed increases on certain platforms and will be stored there if there is
room.  But, if out of room, an alternate (theoretically slower) mechanism is
used.

This patch introduces CONFIG_FLATMEM.  It is used in almost all cases where
there used to be an #ifndef DISCONTIG, because SPARSEMEM and DISCONTIGMEM
often have to compile out the same areas of code.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Martin Bligh <mbligh@aracnet.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Bob Picco <bob.picco@hp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:04 -07:00
Dave Hansen 93b7504e3e [PATCH] Introduce new Kconfig option for NUMA or DISCONTIG
There is some confusion that arose when working on SPARSEMEM patch between
what is needed for DISCONTIG vs. NUMA.

Multiple pg_data_t's are needed for DISCONTIGMEM or NUMA, independently.
All of the current NUMA implementations require an implementation of
DISCONTIG.  Because of this, quite a lot of code which is really needed for
NUMA is actually under DISCONTIG #ifdefs.  For SPARSEMEM, we changed some
of these #ifdefs to CONFIG_NUMA, but that broke the DISCONTIG=y and NUMA=n
case.

Introducing this new NEED_MULTIPLE_NODES config option allows code that is
needed for both NUMA or DISCONTIG to be separated out from code that is
specific to DISCONTIG.

One great advantage of this approach is that it doesn't require every
architecture to be converted over.  All of the current implementations
should "just work", only the ones implementing SPARSEMEM will have to be
fixed up.

The change to free_area_init() makes it work inside, or out of the new
config option.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:03 -07:00
Dave Hansen 348f8b6c48 [PATCH] sparsemem base: reorganize page->flags bit operations
Generify the value fields in the page_flags.  The aim is to allow the location
and size of these fields to be varied.  Additionally we want to move away from
fixed allocations per field whilst still enforcing the overall bit utilisation
limits.  We rely on the compiler to spot and optimise the accessor functions.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:01 -07:00
Dave Hansen 6f167ec721 [PATCH] sparsemem base: simple NUMA remap space allocator
Introduce a simple allocator for the NUMA remap space.  This space is very
scarce, used for structures which are best allocated node local.

This mechanism is also used on non-NUMA ia64 systems with a vmem_map to keep
the pgdat->node_mem_map initialized in a consistent place for all
architectures.

Issues:
o alloc_remap takes a node_id where we might expect a pgdat which was intended
  to allow us to allocate the pgdat's using this mechanism; which we do not yet
  do.  Could have alloc_remap_node() and alloc_remap_nid() for this purpose.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-23 09:45:01 -07:00
Christoph Lameter b7c84c6ada [PATCH] boot_pageset must not be freed.
The boot_pageset needs to be preserved for hotplugging and for off line
processors and nodes. Otherwise pointers will point into memory that has
now a different use. /proc/zoneinfo is currently showing strange results
if processors / nodes are not present.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-22 20:42:32 -07:00
Denis Vlasenko c0d62219a4 [PATCH] Kill stray newline
OOM killer prints a stray newline.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:21 -07:00
Hugh Dickins 334795eca4 [PATCH] bad_page: clear reclaim and slab
Since free_pages_check complains if PG_reclaim or PG_slab is set, bad_page
ought to clear them to avoid repetitive reports (Nikita noticed this too).
Let prep_new_page check page_count and PG_slab as free_pages_check does.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:19 -07:00
Christoph Lameter 2caaad41e4 [PATCH] Reduce size of huge boot per_cpu_pageset
Reduce size of the huge per_cpu_pageset structure in __initdata introduced
into mm1 with the pageset localization patchset.  Use one specially
configured pageset per cpu for all zones and nodes during bootup.

- Avoid duplication of pageset initialization code.
- do the adding to the pageset list before potential free_pages_bulk
  in free_hot_cold_page (otherwise we would have to hold a page
  in a pageset during the period that the boot pagesets are in use).
- remove mistaken __cpuinitdata attribute and revert back to __initdata
  for the boot pageset. A boot pageset is not necessary for cpu hotplug.

Tested for UP SMP NUMA on x86_64 (2.6.12-rc6-mm1): UP SMP NUMA Tested on
IA64 (2.6.12-rc5-mm2): NUMA (2.6.12-rc6-mm1 broken for IA64 because of
sparsemem patches)

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:18 -07:00
Christoph Lameter 4ae7c03943 [PATCH] Periodically drain non local pagesets
The pageset array can potentially acquire a huge amount of memory on large
NUMA systems.  F.e.  on a system with 512 processors and 256 nodes there
will be 256*512 pagesets.  If each pageset only holds 5 pages then we are
talking about 655360 pages.With a 16K page size on IA64 this results in
potentially 10 Gigabytes of memory being trapped in pagesets.  The typical
cases are much less for smaller systems but there is still the potential of
memory being trapped in off node pagesets.  Off node memory may be rarely
used if local memory is available and so we may potentially have memory in
seldom used pagesets without this patch.

The slab allocator flushes its per cpu caches every 2 seconds.  The
following patch flushes the off node pageset caches in the same way by
tying into the slab flush.

The patch also changes /proc/zoneinfo to include the number of pages
currently in each pageset.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:18 -07:00
Janet Morgan 578c2fd6a7 [PATCH] add OOM debug
This patch provides more debug info when the system is OOM.  It displays
memory stats (basically sysrq-m info) from __alloc_pages() when page
allocation fails and during OOM kill.

Thanks to Dave Jones for coming up with the idea.

Signed-off-by: Janet Morgan <janetmor@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:17 -07:00
Benjamin LaHaise c2f29ea111 [PATCH] __read_page_state(): pass unsigned long instead of unsigned
By making the offset argument of __read_page_state an unsigned long instead of
unsigned, we can avoid forcing the compiler to sign extend a usually constant
argument.  This saves 1 instruction on x86-64.

Signed-off-by: Benjamin LaHaise <benjamin.c.lahaise@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:17 -07:00
Benjamin LaHaise 83e5d8f725 [PATCH] __mod_page_state(): pass unsigned long instead of unsigned
By making the offset argument of __mod_page_state an unsigned long instead
of unsigned, we can avoid forcing the compiler to sign extend a usually
constant argument.  This saves 1 instruction on x86-64.

Signed-off-by: Benjamin LaHaise <benjamin.c.lahaise@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:17 -07:00
Darren Hart 1ad539b2bd [PATCH] vm: try_to_free_pages unused argument
try_to_free_pages accepts a third argument, order, but hasn't used it since
before 2.6.0.  The following patch removes the argument and updates all the
calls to try_to_free_pages.

Signed-off-by: Darren Hart <dvhltc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:17 -07:00
Christoph Lameter e7c8d5c995 [PATCH] node local per-cpu-pages
This patch modifies the way pagesets in struct zone are managed.

Each zone has a per-cpu array of pagesets.  So any particular CPU has some
memory in each zone structure which belongs to itself.  Even if that CPU is
not local to that zone.

So the patch relocates the pagesets for each cpu to the node that is nearest
to the cpu instead of allocating the pagesets in the (possibly remote) target
zone.  This means that the operations to manage pages on remote zone can be
done with information available locally.

We play a macro trick so that non-NUMA pmachines avoid the additional
pointer chase on the page allocator fastpath.

AIM7 benchmark on a 32 CPU SGI Altix

w/o patches:
Tasks    jobs/min  jti  jobs/min/task      real       cpu
    1      484.68  100       484.6769     12.01      1.97   Fri Mar 25 11:01:42 2005
  100    27140.46   89       271.4046     21.44    148.71   Fri Mar 25 11:02:04 2005
  200    30792.02   82       153.9601     37.80    296.72   Fri Mar 25 11:02:42 2005
  300    32209.27   81       107.3642     54.21    451.34   Fri Mar 25 11:03:37 2005
  400    34962.83   78        87.4071     66.59    588.97   Fri Mar 25 11:04:44 2005
  500    31676.92   75        63.3538     91.87    742.71   Fri Mar 25 11:06:16 2005
  600    36032.69   73        60.0545     96.91    885.44   Fri Mar 25 11:07:54 2005
  700    35540.43   77        50.7720    114.63   1024.28   Fri Mar 25 11:09:49 2005
  800    33906.70   74        42.3834    137.32   1181.65   Fri Mar 25 11:12:06 2005
  900    34120.67   73        37.9119    153.51   1325.26   Fri Mar 25 11:14:41 2005
 1000    34802.37   74        34.8024    167.23   1465.26   Fri Mar 25 11:17:28 2005

with slab API changes and pageset patch:

Tasks    jobs/min  jti  jobs/min/task      real       cpu
    1      485.00  100       485.0000     12.00      1.96   Fri Mar 25 11:46:18 2005
  100    28000.96   89       280.0096     20.79    150.45   Fri Mar 25 11:46:39 2005
  200    32285.80   79       161.4290     36.05    293.37   Fri Mar 25 11:47:16 2005
  300    40424.15   84       134.7472     43.19    438.42   Fri Mar 25 11:47:59 2005
  400    39155.01   79        97.8875     59.46    590.05   Fri Mar 25 11:48:59 2005
  500    37881.25   82        75.7625     76.82    730.19   Fri Mar 25 11:50:16 2005
  600    39083.14   78        65.1386     89.35    872.79   Fri Mar 25 11:51:46 2005
  700    38627.83   77        55.1826    105.47   1022.46   Fri Mar 25 11:53:32 2005
  800    39631.94   78        49.5399    117.48   1169.94   Fri Mar 25 11:55:30 2005
  900    36903.70   79        41.0041    141.94   1310.78   Fri Mar 25 11:57:53 2005
 1000    36201.23   77        36.2012    160.77   1458.31   Fri Mar 25 12:00:34 2005

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Shobhit Dayal <shobhit@calsoftinc.com>
Signed-off-by: Shai Fultheim <Shai@Scalex86.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:16 -07:00
Martin Hicks 1e7e5a9048 [PATCH] VM: rate limit early reclaim
When early zone reclaim is turned on the LRU is scanned more frequently when a
zone is low on memory.  This limits when the zone reclaim can be called by
skipping the scan if another thread (either via kswapd or sync reclaim) is
already reclaiming from the zone.

Signed-off-by: Martin Hicks <mort@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:14 -07:00
Martin Hicks 0c35bbadc5 [PATCH] VM: add __GFP_NORECLAIM
When using the early zone reclaim, it was noticed that allocating new pages
that should be spread across the whole system caused eviction of local pages.

This adds a new GFP flag to prevent early reclaim from happening during
certain allocation attempts.  The example that is implemented here is for page
cache pages.  We want page cache pages to be spread across the whole system,
and we don't want page cache pages to evict other pages to get local memory.

Signed-off-by:  Martin Hicks <mort@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:14 -07:00
Martin Hicks 753ee72896 [PATCH] VM: early zone reclaim
This is the core of the (much simplified) early reclaim.  The goal of this
patch is to reclaim some easily-freed pages from a zone before falling back
onto another zone.

One of the major uses of this is NUMA machines.  With the default allocator
behavior the allocator would look for memory in another zone, which might be
off-node, before trying to reclaim from the current zone.

This adds a zone tuneable to enable early zone reclaim.  It is selected on a
per-zone basis and is turned on/off via syscall.

Adding some extra throttling on the reclaim was also required (patch
4/4).  Without the machine would grind to a crawl when doing a "make -j"
kernel build.  Even with this patch the System Time is higher on
average, but it seems tolerable.  Here are some numbers for kernbench
runs on a 2-node, 4cpu, 8Gig RAM Altix in the "make -j" run:

			wall  user   sys   %cpu  ctx sw.  sleeps
			----  ----   ---   ----   ------  ------
No patch		1009  1384   847   258   298170   504402
w/patch, no reclaim     880   1376   667   288   254064   396745
w/patch & reclaim       1079  1385   926   252   291625   548873

These numbers are the average of 2 runs of 3 "make -j" runs done right
after system boot.  Run-to-run variability for "make -j" is huge, so
these numbers aren't terribly useful except to seee that with reclaim
the benchmark still finishes in a reasonable amount of time.

I also looked at the NUMA hit/miss stats for the "make -j" runs and the
reclaim doesn't make any difference when the machine is thrashing away.

Doing a "make -j8" on a single node that is filled with page cache pages
takes 700 seconds with reclaim turned on and 735 seconds without reclaim
(due to remote memory accesses).

The simple zone_reclaim syscall program is at
http://www.bork.org/~mort/sgi/zone_reclaim.c

Signed-off-by: Martin Hicks <mort@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:14 -07:00
Nikita Danilov 295ab93497 [PATCH] mm: add /proc/zoneinfo
Add /proc/zoneinfo file to display information about memory zones.  Useful
to analyze VM behaviour.

Signed-off-by: Nikita Danilov <nikita@clusterfs.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-06-21 18:46:14 -07:00
Dean Nelson 7223a93a53 [IA64] Export node_online_map and node_possible_map
Export node_online_map and node_possible_map so that kernel modules can use
the nodemask macros, like, for_each_node() and for_each_online_node().

Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-05-03 12:09:32 -07:00
Pavel Pisa 4dc3b16ba1 [PATCH] DocBook: changes and extensions to the kernel documentation
I have recompiled Linux kernel 2.6.11.5 documentation for me and our
university students again.  The documentation could be extended for more
sources which are equipped by structured comments for recent 2.6 kernels.  I
have tried to proceed with that task.  I have done that more times from 2.6.0
time and it gets boring to do same changes again and again.  Linux kernel
compiles after changes for i386 and ARM targets.  I have added references to
some more files into kernel-api book, I have added some section names as well.
 So please, check that changes do not break something and that categories are
not too much skewed.

I have changed kernel-doc to accept "fastcall" and "asmlinkage" words reserved
by kernel convention.  Most of the other changes are modifications in the
comments to make kernel-doc happy, accept some parameters description and do
not bail out on errors.  Changed <pid> to @pid in the description, moved some
#ifdef before comments to correct function to comments bindings, etc.

You can see result of the modified documentation build at
  http://cmp.felk.cvut.cz/~pisa/linux/lkdb-2.6.11.tar.gz

Some more sources are ready to be included into kernel-doc generated
documentation.  Sources has been added into kernel-api for now.  Some more
section names added and probably some more chaos introduced as result of quick
cleanup work.

Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Signed-off-by: Martin Waitz <tali@admingilde.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:59:25 -07:00
KAMEZAWA Hiroyuki edfbe2b003 [PATCH] count bounce buffer pages in vmstat
This is a patch for counting the number of pages for bounce buffers.  It's
shown in /proc/vmstat.

Currently, the number of bounce pages are not counted anywhere.  So, if
there are many bounce pages, it seems that there are leaked pages.  And
it's difficult for a user to imagine the usage of bounce pages.  So, it's
meaningful to show # of bouce pages.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:58:37 -07:00
Nick Piggin b84a35be02 [PATCH] mempool: NOMEMALLOC and NORETRY
Mempools have 2 problems.

The first is that mempool_alloc can possibly get stuck in __alloc_pages
when they should opt to fail, and take an element from their reserved pool.

The second is that it will happily eat emergency PF_MEMALLOC reserves
instead of going to their reserved pools.

Fix the first by passing __GFP_NORETRY in the allocation calls in
mempool_alloc.  Fix the second by introducing a __GFP_MEMPOOL flag which
directs the page allocator not to allocate from the reserve pool.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:58:36 -07:00
Nick Piggin 8e30f272a9 [PATCH] mm: pcp use non powers of 2 for batch size
Jack Steiner reported this to have fixed his problem (bad colouring):
"The patches fix both problems that I found - bad
 coloring & excessive pages in pagesets."

In most workloads this is not likely to be such a pronounced problem,
however it should help corner cases.  And avoiding powers of 2 in these
types of memory operations is always a good idea.

Signed-off-by: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01 08:58:36 -07:00
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00