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.cSigned-off-by: NMartin Hicks <mort@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Here's the next round of these patches.  These are totally different in
an attempt to meet the "simpler" request after the last patches.  For
reference the earlier threads are:

http://marc.theaimsgroup.com/?l=linux-kernel&m=110839604924587&w=2
http://marc.theaimsgroup.com/?l=linux-mm&m=111461480721249&w=2

This set of patches replaces my other vm- patches that are currently in
-mm.  So they're against 2.6.12-rc5-mm1 about half way through the -mm
patchset.

As I said already this patch is a lot simpler.  The reclaim is turned on
or off on a per-zone basis using a syscall.  I haven't tested the x86
syscall, so it might be wrong.  It uses the existing reclaim/pageout
code with the small addition of a may_swap flag to scan_control
(patch 1/4).

I also added __GFP_NORECLAIM (patch 3/4) so that certain allocation
types can be flagged to never cause reclaim.  This was a deficiency
that was in all of my earlier patch sets.  Previously, doing a big
buffered read would fill one zone with page cache and then start to
reclaim from that same zone, leaving the other zones untouched.

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

This patch:

This adds an extra switch to the scan_control struct.  It simply lets the
reclaim code know if its allowed to swap pages out.

This was required for a simple per-zone reclaimer.  Without this addition
pages would be swapped out as soon as a zone ran out of memory and the early
reclaim kicked in.
Signed-off-by: NMartin Hicks <mort@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Add /proc/zoneinfo file to display information about memory zones.  Useful
to analyze VM behaviour.
Signed-off-by: NNikita Danilov <nikita@clusterfs.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This attempts to merge back the split maps.  This code is mostly copied
from Chrisw's mlock merging from post 2.6.11 trees.  The only difference is
in munmapped_error handling.  Also passed prev to willneed/dontneed,
eventhogh they do not handle it now, since I felt it will be cleaner,
instead of handling prev in madvise_vma in some cases and in subfunction in
some cases.
Signed-off-by: NPrasanna Meda <pmeda@akamai.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This attempts to avoid splittings when it is not needed, that is when
vm_flags are same as new flags.  The idea is from the <2.6.11 mlock_fixup
and others.  This will provide base for the next madvise merging patch.
Signed-off-by: NPrasanna Meda <pmeda@akamai.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix a problem identified by Andrea Arcangeli <andrea@suse.de>

kswapd will set a zone into all_unreclaimable state if it sees that we're not
successfully reclaiming LRU pages.  But that fails to notice that we're
successfully reclaiming slab obects, so we can set all_unreclaimable too soon.

So change shrink_slab() to return a success indication if it actually
reclaimed some objects, and don't assume that the zone is all_unreclaimable if
that is true.  This means that we won't enter all_unreclaimable state if we
are successfully freeing slab objects but we're not yet actually freeing slab
pages, due to internal fragmentation.

(hm, this has a shortcoming.  We could be successfully freeing ZONE_NORMAL
slab objects while being really oom on ZONE_DMA.  If that happens then kswapd
might burn a lot of CPU.  But given that there might be some slab objects in
ZONE_DMA, perhaps that is appropriate.)
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch implements a number of smp_processor_id() cleanup ideas that
Arjan van de Ven and I came up with.

The previous __smp_processor_id/_smp_processor_id/smp_processor_id API
spaghetti was hard to follow both on the implementational and on the
usage side.

Some of the complexity arose from picking wrong names, some of the
complexity comes from the fact that not all architectures defined
__smp_processor_id.

In the new code, there are two externally visible symbols:

 - smp_processor_id(): debug variant.

 - raw_smp_processor_id(): nondebug variant. Replaces all existing
   uses of _smp_processor_id() and __smp_processor_id(). Defined
   by every SMP architecture in include/asm-*/smp.h.

There is one new internal symbol, dependent on DEBUG_PREEMPT:

 - debug_smp_processor_id(): internal debug variant, mapped to
                             smp_processor_id().

Also, i moved debug_smp_processor_id() from lib/kernel_lock.c into a new
lib/smp_processor_id.c file.  All related comments got updated and/or
clarified.

I have build/boot tested the following 8 .config combinations on x86:

 {SMP,UP} x {PREEMPT,!PREEMPT} x {DEBUG_PREEMPT,!DEBUG_PREEMPT}

I have also build/boot tested x64 on UP/PREEMPT/DEBUG_PREEMPT.  (Other
architectures are untested, but should work just fine.)
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NArjan van de Ven <arjan@infradead.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Appended patch will setup compatibility mode TASK_SIZE properly.  This will
fix atleast three known bugs that can be encountered while running
compatibility mode apps.

a) A malicious 32bit app can have an elf section at 0xffffe000.  During
   exec of this app, we will have a memory leak as insert_vm_struct() is
   not checking for return value in syscall32_setup_pages() and thus not
   freeing the vma allocated for the vsyscall page.  And instead of exec
   failing (as it has addresses > TASK_SIZE), we were allowing it to
   succeed previously.

b) With a 32bit app, hugetlb_get_unmapped_area/arch_get_unmapped_area
   may return addresses beyond 32bits, ultimately causing corruption
   because of wrap-around and resulting in SEGFAULT, instead of returning
   ENOMEM.

c) 32bit app doing this below mmap will now fail.

  mmap((void *)(0xFFFFE000UL), 0x10000UL, PROT_READ|PROT_WRITE,
	MAP_FIXED|MAP_PRIVATE|MAP_ANON, 0, 0);
Signed-off-by: NZou Nan hai <nanhai.zou@intel.com>
Signed-off-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch fixes overrun of array pa:
92   		struct idr_layer *pa[MAX_LEVEL];

in

98   		l = idp->layers;
99   		pa[l--] = NULL;

by passing idp->layers, set in
202  		idp->layers = layers;
to function  sub_alloc in
203  		v = sub_alloc(idp, ptr, &id);
Signed-off-by: NZaur Kambarov <zkambarov@coverity.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Fix overrun of static array "ipmi_interfaces" of size 4 at position 4 with
index variable "if_num".

Definitions involved:
297  	#define MAX_IPMI_INTERFACES 4
298  	static ipmi_smi_t ipmi_interfaces[MAX_IPMI_INTERFACES];
Signed-off-by: NZaur Kambarov <zkambarov@coverity.com>
Cc: Corey Minyard <minyard@acm.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

kernel/sched.c: In function `__might_sleep':
kernel/sched.c:5461: warning: int format, long unsigned int arg (arg 3)

We expect irqs_disabled() to return an int (poor man's bool).
Acked-by: NRussell King <rmk@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The implementation is optimal for UltraSPARC-III and later.
It will work, however suboptimally, on UltraSPARC-II and
be treated as a NOP on UltraSPARC-I.

It is not worth code patching this thing as the highest cost
is the code space, and code patching cannot eliminate that.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Here's a much smaller patch to simply disable devfs from the build.  If
this goes well, and there are no complaints for a few weeks, I'll resend
my big "devfs-die-die-die" series of patches that rip the whole thing
out of the kernel tree.
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sit tunnel logging is currently broken:

MAC=01:23:45:67:89:ab->01:23:45:47:89:ac TUNNEL=123.123.  0.123-> 12.123.  6.123

Apart from the broken IP address, MAC addresses are printed differently
for sit tunnels than for everything else.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Drop reference before handing the packets to raw_rcv()
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NKeir Fraser <Keir.Fraser@xl.cam.ac.uk>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I missed this one when fixing up iptable_raw.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since expectation timeouts were made compulsory [1], there is no need to
check for them in ip_conntrack_expect_insert.

[1] https://lists.netfilter.org/pipermail/netfilter-devel/2005-January/018143.htmlSigned-off-by: NPhil Oester <kernel@linuxace.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Netfilter assumes that skb->data == skb->nh.ipv6h
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Here is a simplified version of the patch to fix a bug in IPv6
multicasting. It:

1) adds existence check & EADDRINUSE error for regular joins
2) adds an exception for EADDRINUSE in the source-specific multicast
        join (where a prior join is ok)
3) adds a missing/needed read_lock on sock_mc_list; would've raced
        with destroying the socket on interface down without
4) adds a "leave group" in the (INCLUDE, empty) source filter case.
        This frees unneeded socket buffer memory, but also prevents
        an inappropriate interaction among the 8 socket options that
        mess with this. Some would fail as if in the group when you
        aren't really.

Item #4 had a locking bug in the last version of this patch; rather than
removing the idev->lock read lock only, I've simplified it to remove
all lock state in the path and treat it as a direct "leave group" call for
the (INCLUDE,empty) case it covers. Tested on an MP machine. :-)

Much thanks to HoerdtMickael <hoerdt@clarinet.u-strasbg.fr> who
reported the original bug.
Signed-off-by: NDavid L Stevens <dlstevens@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Essentially netlink at the moment always reports a pid and sequence of 0
always for v6 route activities. 
To understand the repurcassions of this look at:
http://lists.quagga.net/pipermail/quagga-dev/2005-June/003507.html

While fixing this, i took the liberty to resolve the outstanding issue
of IPV6 routes inserted via ioctls to have the correct pids as well.

This patch tries to behave as close as possible to the v4 routes i.e
maintains whatever PID the socket issuing the command owns as opposed to
the process. That made the patch a little bulky.

I have tested against both netlink derived utility to add/del routes as
well as ioctl derived one. The Quagga folks have tested against quagga.
This fixes the problem and so far hasnt been detected to introduce any
new issues.
Signed-off-by: NJamal Hadi Salim <hadi@cyberus.ca>
Acked-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NRobert Olsson <Robert.Olsson@data.slu.se>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/tcp_diag.c uses up to ->args[4]
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Without this change I can't set an attribute exactly PAGE_SIZE in
length. There is no need for zero termination because the interface
uses lengths.

From: Jon Smirl <jonsmirl@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

I think we need this patch or we might "lose" devices to the dpm_irq_off
list if a failure occurs during the suspend process.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

o Following patch sets the attributes for newly allocated inodes for sysfs
  objects. If the object has non-default attributes, inode attributes are
  set as saved in sysfs_dirent->s_iattr, pointer to struct iattr.
Signed-off-by: NManeesh Soni <maneesh@in.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

o This adds ->i_op->setattr VFS method for sysfs inodes. The changed
  attribues are saved in the persistent sysfs_dirent structure as a pointer
  to struct iattr. The struct iattr is allocated only for those sysfs_dirent's
  for which default attributes are getting changed. Thanks to Jon Smirl for
  this suggestion.
Signed-off-by: NManeesh Soni <maneesh@in.ibm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>