Commit Graph

598 Commits

Author SHA1 Message Date
Jens Axboe
2056a782f8 [PATCH] Block queue IO tracing support (blktrace) as of 2006-03-23
Signed-off-by: Jens Axboe <axboe@suse.de>
2006-03-23 20:00:26 +01:00
Andrew Morton
d8733c2956 [PATCH] ext3_readdir: use generic readahead
Linus points out that ext3_readdir's readahead only cuts in when
ext3_readdir() is operating at the very start of the directory.  So for large
directories we end up performing no readahead at all and we suck.

So take it all out and use the core VM's page_cache_readahead().  This means
that ext3 directory reads will use all of readahead's dynamic sizing goop.

Note that we're using the directory's filp->f_ra to hold the readahead state,
but readahead is actually being performed against the underlying blockdev's
address_space.  Fortunately the readahead code is all set up to handle this.

Tested with printk.  It works.  I was struggling to find a real workload which
actually cared.

(The patch also exports page_cache_readahead() to GPL modules)

Cc: "Stephen C. Tweedie" <sct@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:09 -08:00
Rafael J. Wysocki
6e1819d615 [PATCH] swsusp: userland interface
This patch introduces a user space interface for swsusp.

The interface is based on a special character device, called the snapshot
device, that allows user space processes to perform suspend and resume-related
operations with the help of some ioctls and the read()/write() functions.
 Additionally it allows these processes to allocate free swap pages from a
selected swap partition, called the resume partition, so that they know which
sectors of the resume partition are available to them.

The interface uses the same low-level system memory snapshot-handling
functions that are used by the built-it swap-writing/reading code of swsusp.

The interface documentation is included in the patch.

The patch assumes that the major and minor numbers of the snapshot device will
be 10 (ie.  misc device) and 231, the registration of which has already been
requested.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:07 -08:00
Rafael J. Wysocki
f577eb30af [PATCH] swsusp: low level interface
Introduce the low level interface that can be used for handling the
snapshot of the system memory by the in-kernel swap-writing/reading code of
swsusp and the userland interface code (to be introduced shortly).

Also change the way in which swsusp records the allocated swap pages and,
consequently, simplifies the in-kernel swap-writing/reading code (this is
necessary for the userland interface too).  To this end, it introduces two
helper functions in mm/swapfile.c, so that the swsusp code does not refer
directly to the swap internals.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23 07:38:07 -08:00
Christoph Lameter
b20a35035f [PATCH] page migration reorg
Centralize the page migration functions in anticipation of additional
tinkering.  Creates a new file mm/migrate.c

1. Extract buffer_migrate_page() from fs/buffer.c

2. Extract central migration code from vmscan.c

3. Extract some components from mempolicy.c

4. Export pageout() and remove_from_swap() from vmscan.c

5. Make it possible to configure NUMA systems without page migration
   and non-NUMA systems with page migration.

I had to so some #ifdeffing in mempolicy.c that may need a cleanup.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:06 -08:00
Paul Jackson
442295c94b [PATCH] mm: slab cache interleave rotor fix
The alien cache rotor in mm/slab.c assumes that the first online node is
node 0.  Eventually for some archs, especially with hotplug, this will no
longer be true.

Fix the interleave rotor to handle the general case of node numbering.

Signed-off-by: Paul Jackson <pj@sgi.com>
Acked-by: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:06 -08:00
Paul Jackson
fdb7cc5908 [PATCH] mm: hugetlb alloc_fresh_huge_page bogus node loop fix
Fix bogus node loop in hugetlb.c alloc_fresh_huge_page(), which was
assuming that nodes are numbered contiguously from 0 to num_online_nodes().
Once the hotplug folks get this far, that will be false.

Signed-off-by: Paul Jackson <pj@sgi.com>
Acked-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:06 -08:00
Akinobu Mita
9b65ef59d4 [PATCH] fix swap cluster offset
When we've allocated SWAPFILE_CLUSTER pages, ->cluster_next should be the
first index of swap cluster.  But current code probably sets it wrong offset.

Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:06 -08:00
Christoph Lameter
879336c393 [PATCH] drain_node_pages: interrupt latency reduction / optimization
1. Only disable interrupts if there is actually something to free

2. Only dirty the pcp cacheline if we actually freed something.

3. Disable interrupts for each single pcp and not for cleaning
  all the pcps in all zones of a node.

drain_node_pages is called every 2 seconds from cache_reap. This
fix should avoid most disabling of interrupts.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:06 -08:00
Christoph Lameter
b18e7e654d [PATCH] slab: fix drain_array() so that it works correctly with the shared_array
The list_lock also protects the shared array and we call drain_array() with
the shared array.  Therefore we cannot go as far as I wanted to but have to
take the lock in a way so that it also protects the array_cache in
drain_pages.

(Note: maybe we should make the array_cache locking more consistent?  I.e.
always take the array cache lock for shared arrays and disable interrupts
for the per cpu arrays?)

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:06 -08:00
Christoph Lameter
1b55253a7f [PATCH] slab: remove drain_array_locked
Remove drain_array_locked and use that opportunity to limit the time the l3
lock is taken further.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:05 -08:00
Christoph Lameter
aab2207cf8 [PATCH] slab: make drain_array more universal by adding more parameters
And a parameter to drain_array to control the freeing of all objects and
then use drain_array() to replace instances of drain_array_locked with
drain_array.  Doing so will avoid taking locks in those locations if the
arrays are empty.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:05 -08:00
Christoph Lameter
35386e3b0f [PATCH] slab: cache_reap(): further reduction in interrupt holdoff
cache_reap takes the l3->list_lock (disabling interrupts) unconditionally
and then does a few checks and maybe does some cleanup.  This patch makes
cache_reap() only take the lock if there is work to do and then the lock is
taken and released for each cleaning action.

The checking of when to do the next reaping is done without any locking and
becomes racy.  Should not matter since reaping can also be skipped if the
slab mutex cannot be acquired.

The same is true for the touched processing.  If we get this wrong once in
awhile then we will mistakenly clean or not clean the shared cache.  This
will impact performance slightly.

Note that the additional drain_array() function introduced here will fall
out in a subsequent patch since array cleaning will now be very similar
from all callers.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:05 -08:00
Rafael J. Wysocki
248a0301e7 [PATCH] mm: make shrink_all_memory try harder
Make shrink_all_memory() repeat the attempts to free more memory if there
seems to be no pages to free.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:05 -08:00
Chen, Kenneth W
d5d4b0aa4e [PATCH] optimize follow_hugetlb_page
follow_hugetlb_page() walks a range of user virtual address and then fills
in list of struct page * into an array that is passed from the argument
list.  It also gets a reference count via get_page().  For compound page,
get_page() actually traverse back to head page via page_private() macro and
then adds a reference count to the head page.  Since we are doing a virt to
pte look up, kernel already has a struct page pointer into the head page.
So instead of traverse into the small unit page struct and then follow a
link back to the head page, optimize that with incrementing the reference
count directly on the head page.

The benefit is that we don't take a cache miss on accessing page struct for
the corresponding user address and more importantly, not to pollute the
cache with a "not very useful" round trip of pointer chasing.  This adds a
moderate performance gain on an I/O intensive database transaction
workload.

Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:04 -08:00
David Gibson
4866920b93 [PATCH] hugepage: Fix hugepage logic in free_pgtables() harder
Turns out the hugepage logic in free_pgtables() was doubly broken.  The
loop coalescing multiple normal page VMAs into one call to free_pgd_range()
had an off by one error, which could mean it would coalesce one hugepage
VMA into the same bundle (checking 'vma' not 'next' in the loop).  I
transferred this bug into the new is_vm_hugetlb_page() based version.
Here's the fix.

This one didn't bite on powerpc previously for the same reason the
is_hugepage_only_range() problem didn't: powerpc's hugetlb_free_pgd_range()
is identical to free_pgd_range().  It didn't bite on ia64 because the
hugepage region is distant enough from any other region that the separated
PMD_SIZE distance test would always prevent coalescing the two together.

No libhugetlbfs testsuite regressions (ppc64, POWER5).

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:04 -08:00
David Gibson
9da61aef0f [PATCH] hugepage: Fix hugepage logic in free_pgtables()
free_pgtables() has special logic to call hugetlb_free_pgd_range() instead
of the normal free_pgd_range() on hugepage VMAs.  However, the test it uses
to do so is incorrect: it calls is_hugepage_only_range on a hugepage sized
range at the start of the vma.  is_hugepage_only_range() will return true
if the given range has any intersection with a hugepage address region, and
in this case the given region need not be hugepage aligned.  So, for
example, this test can return true if called on, say, a 4k VMA immediately
preceding a (nicely aligned) hugepage VMA.

At present we get away with this because the powerpc version of
hugetlb_free_pgd_range() is just a call to free_pgd_range().  On ia64 (the
only other arch with a non-trivial is_hugepage_only_range()) we get away
with it for a different reason; the hugepage area is not contiguous with
the rest of the user address space, and VMAs are not permitted in between,
so the test can't return a false positive there.

Nonetheless this should be fixed.  We do that in the patch below by
replacing the is_hugepage_only_range() test with an explicit test of the
VMA using is_vm_hugetlb_page().

This in turn changes behaviour for platforms where is_hugepage_only_range()
returns false always (everything except powerpc and ia64).  We address this
by ensuring that hugetlb_free_pgd_range() is defined to be identical to
free_pgd_range() (instead of a no-op) on everything except ia64.  Even so,
it will prevent some otherwise possible coalescing of calls down to
free_pgd_range().  Since this only happens for hugepage VMAs, removing this
small optimization seems unlikely to cause any trouble.

This patch causes no regressions on the libhugetlbfs testsuite - ppc64
POWER5 (8-way), ppc64 G5 (2-way) and i386 Pentium M (UP).

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:03 -08:00
David Gibson
27a85ef1b8 [PATCH] hugepage: Make {alloc,free}_huge_page() local
Originally, mm/hugetlb.c just handled the hugepage physical allocation path
and its {alloc,free}_huge_page() functions were used from the arch specific
hugepage code.  These days those functions are only used with mm/hugetlb.c
itself.  Therefore, this patch makes them static and removes their
prototypes from hugetlb.h.  This requires a small rearrangement of code in
mm/hugetlb.c to avoid a forward declaration.

This patch causes no regressions on the libhugetlbfs testsuite (ppc64,
POWER5).

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:03 -08:00
David Gibson
b45b5bd65f [PATCH] hugepage: Strict page reservation for hugepage inodes
These days, hugepages are demand-allocated at first fault time.  There's a
somewhat dubious (and racy) heuristic when making a new mmap() to check if
there are enough available hugepages to fully satisfy that mapping.

A particularly obvious case where the heuristic breaks down is where a
process maps its hugepages not as a single chunk, but as a bunch of
individually mmap()ed (or shmat()ed) blocks without touching and
instantiating the pages in between allocations.  In this case the size of
each block is compared against the total number of available hugepages.
It's thus easy for the process to become overcommitted, because each block
mapping will succeed, although the total number of hugepages required by
all blocks exceeds the number available.  In particular, this defeats such
a program which will detect a mapping failure and adjust its hugepage usage
downward accordingly.

The patch below addresses this problem, by strictly reserving a number of
physical hugepages for hugepage inodes which have been mapped, but not
instatiated.  MAP_SHARED mappings are thus "safe" - they will fail on
mmap(), not later with an OOM SIGKILL.  MAP_PRIVATE mappings can still
trigger an OOM.  (Actually SHARED mappings can technically still OOM, but
only if the sysadmin explicitly reduces the hugepage pool between mapping
and instantiation)

This patch appears to address the problem at hand - it allows DB2 to start
correctly, for instance, which previously suffered the failure described
above.

This patch causes no regressions on the libhugetblfs testsuite, and makes a
test (designed to catch this problem) pass which previously failed (ppc64,
POWER5).

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:03 -08:00
David Gibson
3935baa9bc [PATCH] hugepage: serialize hugepage allocation and instantiation
Currently, no lock or mutex is held between allocating a hugepage and
inserting it into the pagetables / page cache.  When we do go to insert the
page into pagetables or page cache, we recheck and may free the newly
allocated hugepage.  However, since the number of hugepages in the system
is strictly limited, and it's usualy to want to use all of them, this can
still lead to spurious allocation failures.

For example, suppose two processes are both mapping (MAP_SHARED) the same
hugepage file, large enough to consume the entire available hugepage pool.
If they race instantiating the last page in the mapping, they will both
attempt to allocate the last available hugepage.  One will fail, of course,
returning OOM from the fault and thus causing the process to be killed,
despite the fact that the entire mapping can, in fact, be instantiated.

The patch fixes this race by the simple method of adding a (sleeping) mutex
to serialize the hugepage fault path between allocation and insertion into
pagetables and/or page cache.  It would be possible to avoid the
serialization by catching the allocation failures, waiting on some
condition, then rechecking to see if someone else has instantiated the page
for us.  Given the likely frequency of hugepage instantiations, it seems
very doubtful it's worth the extra complexity.

This patch causes no regression on the libhugetlbfs testsuite, and one
test, which can trigger this race now passes where it previously failed.

Actually, the test still sometimes fails, though less often and only as a
shmat() failure, rather processes getting OOM killed by the VM.  The dodgy
heuristic tests in fs/hugetlbfs/inode.c for whether there's enough hugepage
space aren't protected by the new mutex, and would be ugly to do so, so
there's still a race there.  Another patch to replace those tests with
something saner for this reason as well as others coming...

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:03 -08:00
David Gibson
79ac6ba40e [PATCH] hugepage: Small fixes to hugepage clear/copy path
Move the loops used in mm/hugetlb.c to clear and copy hugepages to their
own functions for clarity.  As we do so, we add some checks of need_resched
- we are, after all copying megabytes of memory here.  We also add
might_sleep() accordingly.  We generally dropped locks around the clear and
copy, already but not everyone has PREEMPT enabled, so we should still be
checking explicitly.

For this to work, we need to remove the clear_huge_page() from
alloc_huge_page(), which is called with the page_table_lock held in the COW
path.  We move the clear_huge_page() to just after the alloc_huge_page() in
the hugepage no-page path.  In the COW path, the new page is about to be
copied over, so clearing it was just a waste of time anyway.  So as a side
effect we also fix the fact that we held the page_table_lock for far too
long in this path by calling alloc_huge_page() under it.

It causes no regressions on the libhugetlbfs testsuite (ppc64, POWER5).

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:03 -08:00
Zhang, Yanmin
8f860591ff [PATCH] Enable mprotect on huge pages
2.6.16-rc3 uses hugetlb on-demand paging, but it doesn_t support hugetlb
mprotect.

From: David Gibson <david@gibson.dropbear.id.au>

  Remove a test from the mprotect() path which checks that the mprotect()ed
  range on a hugepage VMA is hugepage aligned (yes, really, the sense of
  is_aligned_hugepage_range() is the opposite of what you'd guess :-/).

  In fact, we don't need this test.  If the given addresses match the
  beginning/end of a hugepage VMA they must already be suitably aligned.  If
  they don't, then mprotect_fixup() will attempt to split the VMA.  The very
  first test in split_vma() will check for a badly aligned address on a
  hugepage VMA and return -EINVAL if necessary.

From: "Chen, Kenneth W" <kenneth.w.chen@intel.com>

  On i386 and x86-64, pte flag _PAGE_PSE collides with _PAGE_PROTNONE.  The
  identify of hugetlb pte is lost when changing page protection via mprotect.
  A page fault occurs later will trigger a bug check in huge_pte_alloc().

  The fix is to always make new pte a hugetlb pte and also to clean up
  legacy code where _PAGE_PRESENT is forced on in the pre-faulting day.

Signed-off-by: Zhang Yanmin <yanmin.zhang@intel.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:03 -08:00
Steven Pratt
aed75ff3ca [PATCH] readahead: fix initial window size calculation
The current current get_init_ra_size is not optimal across different IO
sizes and max_readahead values.  Here is a quick summary of sizes computed
under current design and under the attached patch.  All of these assume 1st
IO at offset 0, or 1st detected sequential IO.

	32k max, 4k request

	old         new
	-----------------
	 8k        8k
	16k       16k
	32k       32k

	128k max, 4k request
	old         new
	-----------------
	32k         16k
	64k         32k
	128k        64k
	128k       128k

	128k max, 32k request
	old         new
	-----------------
	32k         64k    <-----
	64k        128k
	128k       128k

	512k max, 4k request
	old         new
	-----------------
	4k         32k     <----
	16k        64k
	64k       128k
	128k      256k
	512k      512k

Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Steven Pratt <slpratt@austin.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:03 -08:00
Oleg Nesterov
a564da3964 [PATCH] readahead: ->prev_page can overrun the ahead window
If get_next_ra_size() does not grow fast enough, ->prev_page can overrun
the ahead window.  This means the caller will read the pages from
->ahead_start + ->ahead_size to ->prev_page synchronously.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Steven Pratt <slpratt@austin.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:03 -08:00
Hugh Dickins
d15c023b44 [PATCH] shmem: inline to avoid warning
shmem.c was named and shamed in Jesper's "Building 100 kernels" warnings:
shmem_parse_mpol is only used when CONFIG_TMPFS parses mount options; and
only called from that one site, so mark it inline like its non-NUMA stub.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:02 -08:00
Christoph Lameter
6e5ef1a96e [PATCH] vmscan: emove obsolete checks from shrink_list() and fix unlikely in refill_inactive_zone()
As suggested by Marcelo:

1. The optimization introduced recently for not calling
   page_referenced() during zone reclaim makes two additional checks in
   shrink_list unnecessary.

2. The if (unlikely(sc->may_swap)) in refill_inactive_zone is optimized
   for the zone_reclaim case.  However, most peoples system only does swap.
   Undo that.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Marcelo Tosatti <marcelo.tosatti@cyclades.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:02 -08:00
Nick Piggin
b7ab795b7b [PATCH] mm: more CONFIG_DEBUG_VM
Put a few more checks under CONFIG_DEBUG_VM

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:02 -08:00
Andrew Morton
6626c5d53b [PATCH] mm: prep_zero_page() in irq is a bug
prep_zero_page() uses KM_USER0 and hence may not be used from IRQ context, at
least for highmem pages.

Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Christoph Lameter <christoph@lameter.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:02 -08:00
Nick Piggin
17cf44064a [PATCH] mm: cleanup prep_ stuff
Move the prep_ stuff into prep_new_page.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:02 -08:00
Nick Piggin
7835e98b2e [PATCH] remove set_page_count() outside mm/
set_page_count usage outside mm/ is limited to setting the refcount to 1.
Remove set_page_count from outside mm/, and replace those users with
init_page_count() and set_page_refcounted().

This allows more debug checking, and tighter control on how code is allowed
to play around with page->_count.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:02 -08:00
Nick Piggin
84097518d1 [PATCH] mm: nommu use compound pages
Now that compound page handling is properly fixed in the VM, move nommu
over to using compound pages rather than rolling their own refcounting.

nommu vm page refcounting is broken anyway, but there is no need to have
divergent code in the core VM now, nor when it gets fixed.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: David Howells <dhowells@redhat.com>

(Needs testing, please).
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:01 -08:00
Nick Piggin
0f8053a509 [PATCH] mm: make __put_page internal
Remove __put_page from outside the core mm/.  It is dangerous because it does
not handle compound pages nicely, and misses 1->0 transitions.  If a user
later appears that really needs the extra speed we can reevaluate.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:01 -08:00
Hugh Dickins
a6f563db09 [PATCH] remove VM_DONTCOPY bogosities
Now that it's madvisable, remove two pieces of VM_DONTCOPY bogosity:

1. There was and is no logical reason why VM_DONTCOPY should be in the
   list of flags which forbid vma merging (and those drivers which set
   it are also setting VM_IO, which itself forbids the merge).

2. It's hard to understand the purpose of the VM_HUGETLB, VM_DONTCOPY
   block in vm_stat_account: but never mind, it's under CONFIG_HUGETLB,
   which (unlike CONFIG_HUGETLB_PAGE or CONFIG_HUGETLBFS) has never been
   defined.

Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:01 -08:00
Wu Fengguang
fb8d14e172 [PATCH] mm: shrink_inactive_lis() nr_scan accounting fix
In shrink_inactive_list(), nr_scan is not accounted when nr_taken is 0.
But 0 pages taken does not mean 0 pages scanned.

Move the goto statement below the accounting code to fix it.

Signed-off-by: Wu Fengguang <wfg@mail.ustc.edu.cn>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:00 -08:00
Wu Fengguang
c9b02d970c [PATCH] mm: isolate_lru_pages() scan count fix
In isolate_lru_pages(), *scanned reports one more scan because the scan
counter is increased one more time on exit of the while-loop.

Change the while-loop to for-loop to fix it.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Wu Fengguang <wfg@mail.ustc.edu.cn>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:00 -08:00
Christoph Lameter
7fb2d46d39 [PATCH] zone_reclaim: additional comments and cleanup
Add some comments to explain how zone reclaim works.  And it fixes the
following issues:

- PF_SWAPWRITE needs to be set for RECLAIM_SWAP to be able to write
  out pages to swap. Currently RECLAIM_SWAP may not do that.

- remove setting nr_reclaimed pages after slab reclaim since the slab shrinking
  code does not use that and the nr_reclaimed pages is just right for the
  intended follow up action.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:00 -08:00
Andrew Morton
1742f19fa9 [PATCH] vmscan: rename functions
We have:

	try_to_free_pages
	->shrink_caches(struct zone **zones, ..)
	  ->shrink_zone(struct zone *, ...)
	    ->shrink_cache(struct zone *, ...)
	      ->shrink_list(struct list_head *, ...)
	    ->refill_inactive_list((struct zone *, ...)

which is fairly irrational.

Rename things so that we have

 	try_to_free_pages
 	->shrink_zones(struct zone **zones, ..)
 	  ->shrink_zone(struct zone *, ...)
 	    ->shrink_inactive_list(struct zone *, ...)
 	      ->shrink_page_list(struct list_head *, ...)
	    ->shrink_active_list(struct zone *, ...)

Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Christoph Lameter <christoph@lameter.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:00 -08:00
Andrew Morton
05ff51376f [PATCH] vmscan return nr_reclaimed
Change all the vmscan functions to retunr the number-of-reclaimed pages and
remove scan_conrtol.nr_reclaimed.

Saves ten-odd bytes of text and makes things clearer and more consistent.

The patch also changes the behaviour of zone_reclaim() when it falls back to slab shrinking.  Christoph says

  "Setting this to one means that we will rescan and shrink the slab for
  each allocation if we are out of zone memory and RECLAIM_SLAB is set.  Plus
  if we do an order 0 allocation we do not go off node as intended.

  "We better set this to zero.  This means the allocation will go offnode
  despite us having potentially freed lots of memory on the zone.  Future
  allocations can then again be done from this zone."

Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Christoph Lameter <christoph@lameter.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:00 -08:00
Andrew Morton
69e05944af [PATCH] vmscan: use unsigned longs
Turn basically everything in vmscan.c into `unsigned long'.  This is to avoid
the possibility that some piece of code in there might decide to operate upon
more than 4G (or even 2G) of pages in one hit.

This might be silly, but we'll need it one day.

Cc: Christoph Lameter <clameter@sgi.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:00 -08:00
Andrew Morton
179e96395b [PATCH] vmscan: scan_control cleanup
Initialise as much of scan_control as possible at the declaration site.  This
tidies things up a bit and assures us that all unmentioned fields are zeroed
out.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:54:00 -08:00
Christoph Lameter
8695949a1d [PATCH] Thin out scan_control: remove nr_to_scan and priority
Make nr_to_scan and priority a parameter instead of putting it into scan
control.  This allows various small optimizations and IMHO makes the code
easier to read.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:53:59 -08:00
Andrew Morton
a07fa3944b [PATCH] slab: use on_each_cpu()
Slab duplicates on_each_cpu().

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:53:59 -08:00
Christoph Lameter
ac2b898ca6 [PATCH] slab: Remove SLAB_NO_REAP option
SLAB_NO_REAP is documented as an option that will cause this slab not to be
reaped under memory pressure.  However, that is not what happens.  The only
thing that SLAB_NO_REAP controls at the moment is the reclaim of the unused
slab elements that were allocated in batch in cache_reap().  Cache_reap()
is run every few seconds independently of memory pressure.

Could we remove the whole thing?  Its only used by three slabs anyways and
I cannot find a reason for having this option.

There is an additional problem with SLAB_NO_REAP.  If set then the recovery
of objects from alien caches is switched off.  Objects not freed on the
same node where they were initially allocated will only be reused if a
certain amount of objects accumulates from one alien node (not very likely)
or if the cache is explicitly shrunk.  (Strangely __cache_shrink does not
check for SLAB_NO_REAP)

Getting rid of SLAB_NO_REAP fixes the problems with alien cache freeing.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:53:59 -08:00
Randy Dunlap
911851e6ee [PATCH] slab: fix kernel-doc warnings
Fix kernel-doc warnings in mm/slab.c.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:53:59 -08:00
Pekka Enberg
fcc234f888 [PATCH] mm: kill kmem_cache_t usage
We have struct kmem_cache now so use it instead of the old typedef.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:53:58 -08:00
Ravikiran G Thirumalai
b5d8ca7c50 [PATCH] slab: remove cachep->spinlock
Remove cachep->spinlock.  Locking has moved to the kmem_list3 and most of
the structures protected earlier by cachep->spinlock is now protected by
the l3->list_lock.  slab cache tunables like batchcount are accessed always
with the cache_chain_mutex held.

Patch tested on SMP and NUMA kernels with dbench processes running,
constant onlining/offlining, and constant cache tuning, all at the same
time.

Signed-off-by: Ravikiran Thirumalai <kiran@scalex86.org>
Cc: Christoph Lameter <christoph@lameter.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:53:58 -08:00
Andrew Morton
a737b3e2fc [PATCH] slab cleanup
slab.c has become a bit revolting again.  Try to repair it.

- Coding style fixes

- Don't do assignments-in-if-statements.

- Don't typecast assignments to/from void*

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:53:58 -08:00
Pekka Enberg
f30cf7d13e [PATCH] slab: extract setup_cpu_cache
Extract setup_cpu_cache() function from kmem_cache_create() to make the
latter a little less complex.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:53:58 -08:00
Pekka Enberg
8fea4e96a8 [PATCH] slab: object to index mapping cleanup
Clean up the object to index mapping that has been spread around mm/slab.c.

Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:53:58 -08:00
Nick Piggin
a482289d46 [PATCH] hugepage allocator cleanup
Insert "fresh" huge pages into the hugepage allocator by the same means as
they are freed back into it.  This reduces code size and allows
enqueue_huge_page to be inlined into the hugepage free fastpath.

Eliminate occurances of hugepages on the free list with non-zero refcount.
This can allow stricter refcount checks in future.  Also required for
lockless pagecache.

Signed-off-by: Nick Piggin <npiggin@suse.de>

"This patch also eliminates a leak "cleaned up" by re-clobbering the
refcount on every allocation from the hugepage freelists.  With respect to
the lockless pagecache, the crucial aspect is to eliminate unconditional
set_page_count() to 0 on pages with potentially nonzero refcounts, though
closer inspection suggests the assignments removed are entirely spurious."

Acked-by: William Irwin <wli@holomorphy.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-22 07:53:58 -08:00