Commit Graph

15726 Commits

Author SHA1 Message Date
Christoph Hellwig
db6c1fbb92 romfs: cleanup romfs_fs.h
There's no kernel-only content in it anymore, so move it to header-y
and remove the superflous #ifdef __KERNEL__.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-09 10:49:41 -04:00
Al Viro
74dbbdd7fd New helper: deactivate_locked_super()
Does equivalent of up_write(&s->s_umount); deactivate_super(s);
However, it does not does not unlock it until it's all over.
As the result, it's safe to use to dispose of new superblock on ->get_sb()
failure exits - nobody will see the sucker until it's all over.
Equivalent using up_write/deactivate_super is safe for that purpose
if superblock is either	safe to use or has NULL ->s_root when we unlock.
Normally filesystems take the required precautions, but
	a) we do have bugs in that area in some of them.
	b) up_write/deactivate_super sequence is extremely common,
so the helper makes sense anyway.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-09 10:49:39 -04:00
Jeff Mahoney
677c9b2e39 reiserfs: remove privroot hiding in lookup
With Al Viro's patch to move privroot lookup to fs mount, there's no need
 to have special code to hide the privroot in reiserfs_lookup.

 I've also cleaned up the privroot hiding in reiserfs_readdir_dentry and
 removed the last user of reiserfs_xattrs().

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-09 10:49:39 -04:00
Jeff Mahoney
ab17c4f021 reiserfs: fixup xattr_root caching
The xattr_root caching was broken from my previous patch set. It wouldn't
 cause corruption, but could cause decreased performance due to allocating
 a larger chunk of the journal (~ 27 blocks) than it would actually use.

 This patch loads the xattr root dentry at xattr initialization and creates
 it on-demand. Since we're using the cached dentry, there's no point
 in keeping lookup_or_create_dir around, so that's removed.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-09 10:49:39 -04:00
Al Viro
edcc37a047 Always lookup priv_root on reiserfs mount and keep it
... even if it's a negative dentry.  That way we can set ->d_op on
root before anyone could race with us.  Simplify d_compare(), while
we are at it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-09 10:49:38 -04:00
Greg Kroah-Hartman
e67c85626c Revert driver core: move platform_data into platform_device
This reverts commit 006f4571a1:

	This patch moves platform_data from struct device into
	struct platform_device, based on the two ideas:

	1. Now all platform_driver is registered by platform_driver_register,
	   which makes probe()/release()/... of platform_driver passed parameter
	   of platform_device *, so platform driver can get platform_data from
	   platform_device;

	2. Other kind of devices do not need to use platform_data, we can
	   decrease size of device if moving it to platform_device.

	Taking into consideration of thousands of files to be fixed and they
	can't be finished in one night(maybe it will take a long time), so we
	keep platform_data in device to allow two kind of cases coexist until
	all platform devices pass its platfrom data from
	platform_device->platform_data.

	All patches to do this kind of conversion are welcome.

As we don't really want to do it, it was a bad idea.

Cc: David Brownell <david-b@pacbell.net>
Cc: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-05-08 19:22:21 -07:00
Linus Torvalds
d7a5926978 Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6: (32 commits)
  [CIFS] Fix double list addition in cifs posix open code
  [CIFS] Allow raw ntlmssp code to be enabled with sec=ntlmssp
  [CIFS] Fix SMB uid in NTLMSSP authenticate request
  [CIFS] NTLMSSP reenabled after move from connect.c to sess.c
  [CIFS] Remove sparse warning
  [CIFS] remove checkpatch warning
  [CIFS] Fix final user of old string conversion code
  [CIFS] remove cifs_strfromUCS_le
  [CIFS] NTLMSSP support moving into new file, old dead code removed
  [CIFS] Fix endian conversion of vcnum field
  [CIFS] Remove trailing whitespace
  [CIFS] Remove sparse endian warnings
  [CIFS] Add remaining ntlmssp flags and standardize field names
  [CIFS] Fix build warning
  cifs: fix length handling in cifs_get_name_from_search_buf
  [CIFS] Remove unneeded QuerySymlink call and fix mapping for unmapped status
  [CIFS] rename cifs_strndup to cifs_strndup_from_ucs
  Added loop check when mounting DFS tree.
  Enable dfs submounts to handle remote referrals.
  [CIFS] Remove older session setup implementation
  ...
2009-05-07 21:13:24 -07:00
David S. Miller
356d6c2d55 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-2.6 2009-05-05 12:00:53 -07:00
Pablo Neira Ayuso
280f37afa2 netfilter: xt_cluster: fix use of cluster match with 32 nodes
This patch fixes a problem when you use 32 nodes in the cluster
match:

% iptables -I PREROUTING -t mangle -i eth0 -m cluster \
  --cluster-total-nodes  32  --cluster-local-node  32 \
  --cluster-hash-seed 0xdeadbeef -j MARK --set-mark 0xffff
iptables: Invalid argument. Run `dmesg' for more information.
% dmesg | tail -1
xt_cluster: this node mask cannot be higher than the total number of nodes

The problem is related to this checking:

if (info->node_mask >= (1 << info->total_nodes)) {
	printk(KERN_ERR "xt_cluster: this node mask cannot be "
			"higher than the total number of nodes\n");
	return false;
}

(1 << 32) is 1. Thus, the checking fails.

BTW, I said this before but I insist: I have only tested the cluster
match with 2 nodes getting ~45% extra performance in an active-active setup.
The maximum limit of 32 nodes is still completely arbitrary. I'd really
appreciate if people that have more nodes in their setups let me know.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-05-05 17:46:07 +02:00
Linus Torvalds
80445de577 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (30 commits)
  e1000: fix virtualization bug
  bonding: fix alb mode locking regression
  Bluetooth: Fix issue with sysfs handling for connections
  usbnet: CDC EEM support (v5)
  tcp: Fix tcp_prequeue() to get correct rto_min value
  ehea: fix invalid pointer access
  ne2k-pci: Do not register device until initialized.
  Subject: [PATCH] br2684: restore net_dev initialization
  net: Only store high 16 bits of kernel generated filter priorities
  virtio_net: Fix function name typo
  virtio_net: Cleanup command queue scatterlist usage
  bonding: correct the cleanup in bond_create()
  virtio: add missing include to virtio_net.h
  smsc95xx: add support for LAN9512 and LAN9514
  smsc95xx: configure LED outputs
  netconsole: take care of NETDEV_UNREGISTER event
  xt_socket: checks for the state of nf_conntrack
  bonding: bond_slave_info_query() fix
  cxgb3: fixing gcc 4.4 compiler warning: suggest parentheses around operand of ‘!’
  netfilter: use likely() in xt_info_rdlock_bh()
  ...
2009-05-05 08:26:10 -07:00
Patrick McHardy
a7ca7fccac netfilter: add missing linux/types.h include to xt_LED.h
Pointed out by Dave Miller:

  CHECK   include/linux/netfilter (57 files)
/home/davem/src/GIT/net-2.6/usr/include/linux/netfilter/xt_LED.h:6: found __[us]{8,16,32,64} type without #include <linux/types.h>

Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-05-05 14:31:12 +02:00
Omar Laazimani
9f722c0978 usbnet: CDC EEM support (v5)
This introduces a CDC Ethernet Emulation Model (EEM) host side
driver to support USB EEM devices.

EEM is different from the Ethernet Control Model (ECM) currently
supported by the "CDC Ethernet" driver.  One key difference is
that it doesn't require of USB interface alternate settings to
manage interface state; some maldesigned hardware can't handle
that part of USB.  It also avoids a separate USB interface for
control and status updates.

[ dbrownell@users.sourceforge.net: fix skb leaks, add rx packet
checks, improve fault handling, EEM conformance updates, cleanup ]

Signed-off-by: Omar Laazimani <omar.oberthur@gmail.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-04 12:01:43 -07:00
Linus Torvalds
7b39da786a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6:
  ide-cd: fix REQ_QUIET tests in cdrom_decode_status

Fix up trivial conflicts in include/linux/blkdev.h
2009-05-02 16:48:32 -07:00
Linus Torvalds
8c0c3f7ff0 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: document the multi-touch (MT) protocol
  Input: add detailed multi-touch finger data report protocol
  Input: allow certain EV_ABS events to bypass all filtering
  Input: bcm5974 - add documentation for the driver
  Input: bcm5974 - augment debug information
  Input: bcm5974 - Add support for the Macbook 5 (Unibody)
  Input: bcm5974 - add quad-finger tapping
  Input: bcm5974 - prepare for a new trackpad header type
  Input: appletouch - fix DMA to/from stack buffer
  Input: wacom - fix TabletPC touch bug
  Input: lifebook - add DMI entry for Fujitsu B-2130
  Input: ALPS - add signature for Toshiba Satellite Pro M10
  Input: elantech - make sure touchpad is really in absolute mode
  Input: elantech - provide a workaround for jumpy cursor on firmware 2.34
  Input: ucb1400 - use disable_irq_nosync() in irq handler
  Input: tsc2007 - use disable_irq_nosync() in irq handler
  Input: sa1111ps2 - use disable_irq_nosync() in irq handlers
  Input: omap-keypad - use disable_irq_nosync() in irq handler
2009-05-02 16:35:45 -07:00
Trond Myklebust
f75e6745aa SUNRPC: Fix the problem of EADDRNOTAVAIL syslog floods on reconnect
See http://bugzilla.kernel.org/show_bug.cgi?id=13034

If the port gets into a TIME_WAIT state, then we cannot reconnect without
binding to a new port.

Tested-by: Petr Vandrovec <petr@vandrovec.name>
Tested-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-02 16:35:08 -07:00
KOSAKI Motohiro
00a62ce91e mm: fix Committed_AS underflow on large NR_CPUS environment
The Committed_AS field can underflow in certain situations:

>         # while true; do cat /proc/meminfo  | grep _AS; sleep 1; done | uniq -c
>               1 Committed_AS: 18446744073709323392 kB
>              11 Committed_AS: 18446744073709455488 kB
>               6 Committed_AS:    35136 kB
>               5 Committed_AS: 18446744073709454400 kB
>               7 Committed_AS:    35904 kB
>               3 Committed_AS: 18446744073709453248 kB
>               2 Committed_AS:    34752 kB
>               9 Committed_AS: 18446744073709453248 kB
>               8 Committed_AS:    34752 kB
>               3 Committed_AS: 18446744073709320960 kB
>               7 Committed_AS: 18446744073709454080 kB
>               3 Committed_AS: 18446744073709320960 kB
>               5 Committed_AS: 18446744073709454080 kB
>               6 Committed_AS: 18446744073709320960 kB

Because NR_CPUS can be greater than 1000 and meminfo_proc_show() does
not check for underflow.

But NR_CPUS proportional isn't good calculation.  In general,
possibility of lock contention is proportional to the number of online
cpus, not theorical maximum cpus (NR_CPUS).

The current kernel has generic percpu-counter stuff.  using it is right
way.  it makes code simplify and percpu_counter_read_positive() don't
make underflow issue.

Reported-by: Dave Hansen <dave@linux.vnet.ibm.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Eric B Munson <ebmunson@us.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: <stable@kernel.org>		[All kernel versions]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-02 15:36:10 -07:00
Grant Likely
0763ed2355 of: make of_(un)register_platform_driver common code
Some drivers using of_register_platform_driver() wrapper break on sparc
because the wrapper isn't in the header file.  This patch moves it from
Microblaze and PowerPC implementations and makes it common code.

Fixes this sparc64 allmodconfig build error (at least):

drivers/leds/leds-gpio.c: In function `gpio_led_init':
drivers/leds/leds-gpio.c:295: error: implicit declaration of function `of_register_platform_driver'
drivers/leds/leds-gpio.c: In function `gpio_led_exit':
drivers/leds/leds-gpio.c:311: error: implicit declaration of function `of_unregister_platform_driver'

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-02 15:36:10 -07:00
Ivan Kokshaysky
74641f584d alpha: binfmt_aout fix
This fixes the problem introduced by commit 3bfacef412 (get rid of
special-casing the /sbin/loader on alpha): osf/1 ecoff binary segfaults
when binfmt_aout built as module.  That happens because aout binary
handler gets on the top of the binfmt list due to late registration, and
kernel attempts to execute the binary without preparatory work that must
be done by binfmt_loader.

Fixed by changing the registration order of the default binfmt handlers
using list_add_tail() and introducing insert_binfmt() function which
places new handler on the top of the binfmt list.  This might be generally
useful for installing arch-specific frontends for default handlers or just
for overriding them.

Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Richard Henderson <rth@twiddle.net
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-02 15:36:10 -07:00
Daisuke Nishimura
ae3abae64f memcg: fix mem_cgroup_shrink_usage()
Current mem_cgroup_shrink_usage() has two problems.

1. It doesn't call mem_cgroup_out_of_memory and doesn't update
   last_oom_jiffies, so pagefault_out_of_memory invokes global OOM.

2. Considering hierarchy, shrinking has to be done from the
   mem_over_limit, not from the memcg which the page would be charged to.

mem_cgroup_try_charge_swapin() does all of these things properly, so we
use it and call cancel_charge_swapin when it succeeded.

The name of "shrink_usage" is not appropriate for this behavior, so we
change it too.

Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.cn>
Cc: Paul Menage <menage@google.com>
Cc: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Cc: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-02 15:36:09 -07:00
Grant Likely
c047fcd245 virtio: add missing include to virtio_net.h
virtio_net.h uses the macro ETH_ALEN which is defined in linux/if_ether.h.
Discovered when hacking on virtio-over-pci patches.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-01 15:34:02 -07:00
Eric Dumazet
0f3d042ed2 netfilter: use likely() in xt_info_rdlock_bh()
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-01 09:10:46 -07:00
Borislav Petkov
96c1674397 ide-cd: fix REQ_QUIET tests in cdrom_decode_status
Original patch (dfa4411cc3) was buggy.
This is a more proper fix which introduces blk_rq_quiet() macro
alleviating the need for dumb, too short caching variables.

Thanks to Helge Deller and Bart for debugging this.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Reported-and-tested-by: Helge Deller <deller@gmx.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-04-30 18:24:34 +02:00
Steve French
912bc6ae3d Merge branch 'master' of /pub/scm/linux/kernel/git/torvalds/linux-2.6 2009-04-30 15:36:52 +00:00
Jeff Layton
d37dc42ab6 nls: add a nls_nullsize inline
It's possible for character sets to require a multi-byte null
string terminator. Add a helper function that determines the size
of the null terminator at runtime.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2009-04-30 15:32:11 +00:00
Linus Torvalds
3dacbdad24 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (24 commits)
  e100: do not go D3 in shutdown unless system is powering off
  netfilter: revised locking for x_tables
  Bluetooth: Fix connection establishment with low security requirement
  Bluetooth: Add different pairing timeout for Legacy Pairing
  Bluetooth: Ensure that HCI sysfs add/del is preempt safe
  net: Avoid extra wakeups of threads blocked in wait_for_packet()
  net: Fix typo in net_device_ops description.
  ipv4: Limit size of route cache hash table
  Add reference to CAPI 2.0 standard
  Documentation/isdn/INTERFACE.CAPI
  update Documentation/isdn/00-INDEX
  ixgbe: Fix WoL functionality for 82599 KX4 devices
  veth: prevent oops caused by netdev destructor
  xfrm: wrong hash value for temporary SA
  forcedeth: tx timeout fix
  net: Fix LL_MAX_HEADER for CONFIG_TR_MODULE
  mlx4_en: Handle page allocation failure during receive
  mlx4_en: Fix cleanup flow on cq activation
  vlan: update vlan carrier state for admin up/down
  netfilter: xt_recent: fix stack overread in compat code
  ...
2009-04-29 07:55:45 -07:00
Stephen Hemminger
942e4a2bd6 netfilter: revised locking for x_tables
The x_tables are organized with a table structure and a per-cpu copies
of the counters and rules. On older kernels there was a reader/writer 
lock per table which was a performance bottleneck. In 2.6.30-rc, this
was converted to use RCU and the counters/rules which solved the performance
problems for do_table but made replacing rules much slower because of
the necessary RCU grace period.

This version uses a per-cpu set of spinlocks and counters to allow to
table processing to proceed without the cache thrashing of a global
reader lock and keeps the same performance for table updates.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-28 22:36:33 -07:00
Randy Dunlap
9f6532519f regulator: fix header file missing kernel-doc
Add regulator header file missing kernel-doc:

Warning(include/linux/regulator/driver.h:117): No description found for parameter 'set_mode'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
cc:	Liam Girdwood <lrg@slimlogic.co.uk>
cc:	Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2009-04-28 18:58:06 +01:00
Henrik Rydberg
5e5ee686e3 Input: add detailed multi-touch finger data report protocol
In order to utilize the full power of the new multi-touch devices, a
way to report detailed finger data to user space is needed. This patch
adds a multi-touch (MT) protocol which allows drivers to report details
for an arbitrary number of fingers.

The driver sends a SYN_MT_REPORT event via the input_mt_sync() function
when a complete finger has been reported.

In order to stay compatible with existing applications, the data
reported in a finger packet must not be recognized as single-touch
events. In addition, all finger data must bypass input filtering,
since subsequent events of the same type refer to different fingers.

A set of ABS_MT events with the desired properties are defined. The
events are divided into categories, to allow for partial implementation.
The minimum set consists of ABS_MT_TOUCH_MAJOR, ABS_MT_POSITION_X and
ABS_MT_POSITION_Y, which allows for multiple fingers to be tracked.
If the device supports it, the ABS_MT_WIDTH_MAJOR may be used to provide
the size of the approaching finger. Anisotropy and direction may be
specified with ABS_MT_TOUCH_MINOR, ABS_MT_WIDTH_MINOR and
ABS_MT_ORIENTATION. Devices with more granular information may specify
general shapes as blobs, i.e., as a sequence of rectangular shapes
grouped together by a ABS_MT_BLOB_ID. Finally, the ABS_MT_TOOL_TYPE
may be used to specify whether the touching tool is a finger or a pen.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2009-04-28 09:36:24 -07:00
Henrik Rydberg
6916d97f6e Input: bcm5974 - add quad-finger tapping
The integrated button on the new unibody Macbooks presents a need to
report explicit four-finger actions. Evidently, the finger pressing
the button is also touching the trackpad, so in order to fully support
three-finger actions, the driver must be able to report four-finger
actions. This patch adds a new button, BTN_TOOL_QUADTAP, which
achieves this.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2009-04-28 09:35:12 -07:00
Eric Dumazet
bf368e4e70 net: Avoid extra wakeups of threads blocked in wait_for_packet()
In 2.6.25 we added UDP mem accounting.

This unfortunatly added a penalty when a frame is transmitted, since
we have at TX completion time to call sock_wfree() to perform necessary
memory accounting. This calls sock_def_write_space() and utimately
scheduler if any thread is waiting on the socket.
Thread(s) waiting for an incoming frame was scheduled, then had to sleep
again as event was meaningless.

(All threads waiting on a socket are using same sk_sleep anchor)

This adds lot of extra wakeups and increases latencies, as noted
by Christoph Lameter, and slows down softirq handler.

Reference : http://marc.info/?l=linux-netdev&m=124060437012283&w=2 

Fortunatly, Davide Libenzi recently added concept of keyed wakeups
into kernel, and particularly for sockets (see commit
37e5540b3c 
epoll keyed wakeups: make sockets use keyed wakeups)

Davide goal was to optimize epoll, but this new wakeup infrastructure
can help non epoll users as well, if they care to setup an appropriate
handler.

This patch introduces new DEFINE_WAIT_FUNC() helper and uses it
in wait_for_packet(), so that only relevant event can wakeup a thread
blocked in this function.

Trace of function calls from bnx2 TX completion bnx2_poll_work() is :
__kfree_skb()
 skb_release_head_state()
  sock_wfree()
   sock_def_write_space()
    __wake_up_sync_key()
     __wake_up_common()
      receiver_wake_function() : Stops here since thread is waiting for an INPUT


Reported-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-28 02:24:21 -07:00
Tim Abbott
27b1833279 Remove unused support code for refok sections.
The old refok sections

  .text.init.refok
  .data.init.refok
  .exit.text.refok

have been deprecated since commit
312b1485fb.  After the other patches in
this patch series nothing is put in these sections, so clean things up
by eliminating all the remaining references to them.

Signed-off-by: Tim Abbott <tabbott@mit.edu>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-27 19:51:58 -07:00
Linus Torvalds
3fb8e49200 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI: only save/restore existent registers in the PCIe capability
  x86/PCI: don't bother with root quirks if _CRS is used
  docbooks: add/fix PCI kernel-doc
  PCI: cleanup debug output resources
  x86/PCI: set_pci_bus_resources_arch_default cleanups
  x86/PCI: Move set_pci_bus_resources_arch_default into arch/x86
  x86/PCI: don't call e820_all_mapped with -1 in the mmconfig case
  PCI quirk: disable MSI on VIA VT3364 chipsets
2009-04-27 11:59:46 -07:00
Mike Rapoport
37b607c5ac net: Fix typo in net_device_ops description.
Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-27 05:45:54 -07:00
Adrian Bunk
c759a6b4e1 net: Fix LL_MAX_HEADER for CONFIG_TR_MODULE
Unless I miss anything this should fix a bug.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-27 02:36:20 -07:00
Tim Abbott
c80d471a47 Add new HEAD_TEXT_SECTION macro.
This patch is preparation for replacing all uses of ".head.text" or
".text.head" in the kernel with macros, so that the section name can
later be changed without having to touch a lot of the kernel.

Since some linker scripts do more complex things than referencing
HEAD_TEXT, we add a HEAD_TEXT_SECTION macro that just contains the
actual name.

I've defined HEAD_TEXT_SECTION in a new header,
include/linux/section-names.h, so that this section name only needs to
appear in one place.  I anticipate creating similar macro structures
for a number of other section names.

The long-term goal here is to be able to change the kernel's magic
section names to those that are compatible with -ffunction-sections
-fdata-sections.  This requires renaming all magic sections with names
of the form ".text.foo".

Signed-off-by: Tim Abbott <tabbott@mit.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-26 09:20:38 -07:00
David S. Miller
1c41e238e0 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-2.6 2009-04-25 17:46:34 -07:00
Linus Torvalds
ef54b1bb2e Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (34 commits)
  ACPI, i915: Register ACPI video even when not modesetting
  Revert "ACPICA: delete check for AML access to port 0x81-83"
  I/O port protection: update for windows compatibility.
  sony-laptop: always try to unblock rfkill on load
  sony-laptop: fix bogus error message display on resume
  ACPI: EC: Fix ACPI EC resume non-query interrupt message
  sony-laptop: SNC input event 38 fix
  sony-laptop: SNC 127 Initialization Fix
  sony-laptop: Duplicate SNC 127 Event Fix
  ACPI: prevent processor.max_cstate=0 boot crash
  ACPI/hpet: prevent boot hang when hpet=force used on ICH-4M
  ACPI: delete obsolete "bus master activity" proc field
  ACPI: idle: mark_tsc_unstable() at init-time, not run-time
  ACPI: add /sys/firmware/acpi/interrupts/sci_not counter
  ACPI video: fix an error when the brightness levels on AC and on Battery are same
  acpi-cpufreq: Do not let get_measured perf depend on internal variable
  acpi-cpufreq: style-only: add parens to math expression
  acpi-cpufreq: Cleanup: Use printk_once
  x86, acpi_cpufreq: Fix the NULL pointer dereference in get_measured_perf
  thinkpad-acpi: bump up version to 0.23
  ...
2009-04-24 08:48:17 -07:00
Linus Torvalds
a4277bf122 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: Fix potential inode allocation soft lockup in Orlov allocator
  ext4: Make the extent validity check more paranoid
  jbd: use SWRITE_SYNC_PLUG when writing synchronous revoke records
  jbd2: use SWRITE_SYNC_PLUG when writing synchronous revoke records
  ext4: really print the find_group_flex fallback warning only once
2009-04-24 08:37:40 -07:00
Linus Torvalds
d72cd3a90e Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6:
  USB: pwc : do not pass stack allocated buffers to USB core.
  USB: otg: Fix bug on remove path without transceiver
  USB: correct error handling in cdc-wdm
  USB: removal of tty->low_latency hack dating back to the old serial code
  USB: serial: sierra driver bug fix for composite interface
  USB: gadget: omap_udc uses platform_driver_probe()
  USB: ci13xxx_udc: fix build error
  USB: musb: Prevent multiple includes of musb.h
  USB: pass mem_flags to dma_alloc_coherent
  USB: g_file_storage: fix use-after-free bug when closing files
  USB: ehci-sched.c: EHCI SITD scheduling bugfix
  USB: fix mos7840 problem with minor numbers
  USB: mos7840: add new device id
  USB: musb: fix build when !CONFIG_PM
  USB: musb: Remove my email address from few musb related drivers
  USB: Gadget: MIPS CI13xxx UDC bugfixes
  USB: Unusual Device support for Gold MP3 Player Energy
  USB: serial: fix lifetime and locking problems
2009-04-24 08:36:06 -07:00
Linus Torvalds
12bac708e6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes:
  GFS2: Ensure that the inode goal block settings are updated
  GFS2: Fix bug in block allocation
  bitops: Add __ffs64 bitop
2009-04-24 08:27:02 -07:00
Linus Torvalds
60911731fe Merge branch 'kvm-updates/2.6.30' of git://git.kernel.org/pub/scm/virt/kvm/kvm
* 'kvm-updates/2.6.30' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: Unregister cpufreq notifier on unload
  KVM: x86: release time_page on vcpu destruction
  KVM: Fix overlapping check for memory slots
  KVM: MMU: disable global page optimization
  KVM: ia64: fix locking order entering guest
  KVM: MMU: Fix off-by-one calculating large page count
2009-04-24 08:26:01 -07:00
Pablo Neira Ayuso
71951b64a5 netfilter: nf_ct_dccp: add missing role attributes for DCCP
This patch adds missing role attribute to the DCCP type, otherwise
the creation of entries is not of any use.

The attribute added is CTA_PROTOINFO_DCCP_ROLE which contains the
role of the conntrack original tuple.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>
2009-04-24 16:58:41 +02:00
Linus Torvalds
97c68d00db Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  cfq-iosched: cache prio_tree root in cfqq->p_root
  cfq-iosched: fix bug with aliased request and cooperation detection
  cfq-iosched: clear ->prio_trees[] on cfqd alloc
  block: fix intermittent dm timeout based oops
  umem: fix request_queue lock warning
  block: simplify I/O stat accounting
  pktcdvd.h should include mempool.h
  cfq-iosched: use the default seek distance when there aren't enough seek samples
  cfq-iosched: make seek_mean converge more quickly
  block: make blk_abort_queue() ignore non-request based devices
  block: include empty disks in /proc/diskstats
  bio: use bio_kmalloc() in copy/map functions
  bio: fix bio_kmalloc()
  block: fix queue bounce limit setting
  block: fix SG_IO vector request data length handling
  scatterlist: make sure sg_miter_next() doesn't return 0 sized mappings
2009-04-24 07:48:24 -07:00
Linus Torvalds
f8c3301e83 Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
  powerpc: Fix modular build of ide-pmac when mediabay is built in
  powerpc/pasemi: Fix build error on UP
  powerpc: Make macintosh/mediabay driver depend on CONFIG_BLOCK
  maintainers: Fix PS3 patterns
  powerpc/ps3: Fix CONFIG_PS3_FLASH=n build warning
  powerpc/32: Don't clobber personality flags on exec
  powerpc: Fix crash on CPU hotplug
  powerpc/85xx: Remove defconfigs that mpc85xx_{smp_}defconfig cover
  powerpc/85xx: Added SMP defconfig
  powerpc/85xx: Enabled a bunch of FSL specific drivers/options
  powerpc/85xx: Updated generic mpc85xx_defconfig
  powerpc: don't disable SATA interrupts on Freescale MPC8610 HPCD
  fsl_rio: Pass the proper device to dma mapping routines
  powerpc: Fix of_node_put() exit path in of_irq_map_one()
  powerpc/5200: defconfig updates
  powerpc/5200: Add FLASH nodes to lite5200 device tree
  powerpc/device-tree: Document MTD nodes with multiple "reg" tuples
  powerpc/of-device-tree: Factor MTD physmap bindings out of booting-without-of
  powerpc/5200: Bring the legacy fsl_spi_platform_data hooks back
2009-04-24 07:44:58 -07:00
Jerome Marchand
42dad7647a block: simplify I/O stat accounting
This simplifies I/O stat accounting switching code and separates it
completely from I/O scheduler switch code.

Requests are accounted according to the state of their request queue
at the time of the request allocation. There is no need anymore to
flush the request queue when switching I/O accounting state.

Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-24 08:54:21 +02:00
Alexander Beregalov
097102c2d0 pktcdvd.h should include mempool.h
Fix this build error:
In file included from fs/compat_ioctl.c:104:
include/linux/pktcdvd.h:285: error: expected specifier-qualifier-list before 'mempool_t'

Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-24 08:54:21 +02:00
Len Brown
6e6c348fb2 Merge branch 'irq' into release 2009-04-24 01:34:59 -04:00
Mark A. Greer
fbfc396efb USB: musb: Prevent multiple includes of musb.h
Add #ifndef to musb header file to prevent multiple inclusions.

Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-23 14:15:28 -07:00
Steven Whitehouse
952043ac12 bitops: Add __ffs64 bitop
Finds the first set bit in a 64 bit word. This is required in order
to fix a bug in GFS2, but I think it should be a generic function
in case of future users.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Reviewed-by: Christoph Lameter <cl@linux.com>
Reviewed-by: Willy Tarreau <w@1wt.eu>
2009-04-23 10:06:35 +01:00
Yu Zhao
1b6b8ce2ac PCI: only save/restore existent registers in the PCIe capability
PCIe 1.1 base neither requires the endpoint to implement the entire
PCIe capability structure nor specifies default values of registers
that are not implemented by the device. So we only save and restore
registers that must be implemented by different device types if the
device PCIe capability version is 1.

PCIe 1.1 Capability Structure Expansion ECN and PCIe 2.0 requires
all registers in the PCIe capability to be either implemented or
hardwired to 0. Their PCIe capability version is 2.

Signed-off-by: Yu Zhao <yu.zhao@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2009-04-22 15:59:41 -07:00
Jan Kiszka
4cd481f68d KVM: Fix overlapping check for memory slots
When checking for overlapping slots on registration of a new one, kvm
currently also considers zero-length (ie. deleted) slots and rejects
requests incorrectly. This finally denies user space from joining slots.
Fix the check by skipping deleted slots and advertise this via a
KVM_CAP_JOIN_MEMORY_REGIONS_WORKS.

Cc: stable@kernel.org
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-04-22 13:52:09 +03:00
Tejun Heo
71982a409f block: include empty disks in /proc/diskstats
/proc/diskstats used to show stats for all disks whether they're
zero-sized or not and their non-zero partitions.  Commit
074a7aca7a accidentally changed the
behavior such that it doesn't print out zero sized disks.  This patch
implements DISK_PITER_INCL_EMPTY_PART0 flag to partition iterator and
uses it in diskstats_show() such that empty part0 is shown in
/proc/diskstats.

Reported and bisectd by Dianel Collins.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Daniel Collins <solemnwarning@solemnwarning.no-ip.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-22 08:35:10 +02:00
Tejun Heo
451a9ebf65 bio: fix bio_kmalloc()
Impact: fix bio_kmalloc() and its destruction path

bio_kmalloc() was broken in two ways.

* bvec_alloc_bs() first allocates bvec using kmalloc() and then
  ignores it and allocates again like non-kmalloc bvecs.

* bio_kmalloc_destructor() didn't check for and free bio integrity
  data.

This patch fixes the above problems.  kmalloc patch is separated out
from bio_alloc_bioset() and allocates the requested number of bvecs as
inline bvecs.

* bio_alloc_bioset() no longer takes NULL @bs.  None other than
  bio_kmalloc() used it and outside users can't know how it was
  allocated anyway.

* Define and use BIO_POOL_NONE so that pool index check in
  bvec_free_bs() triggers if inline or kmalloc allocated bvec gets
  there.

* Relocate destructors on top of each allocation function so that how
  they're used is more clear.

Jens Axboe suggested allocating bvecs inline.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-22 08:35:10 +02:00
Paul Mackerras
5bd3ef84d7 Merge branch 'merge' of git://git.secretlab.ca/git/linux-2.6 into merge 2009-04-22 13:02:09 +10:00
Arjan van de Ven
d4d5291c8c driver synchronization: make scsi_wait_scan more advanced
There is currently only one way for userspace to say "wait for my storage
device to get ready for the modules I just loaded": to load the
scsi_wait_scan module. Expectations of userspace are that once this
module is loaded, all the (storage) devices for which the drivers
were loaded before the module load are present.

Now, there are some issues with the implementation, and the async
stuff got caught in the middle of this: The existing code only
waits for the scsy async probing to finish, but it did not take
into account at all that probing might not have begun yet.
(Russell ran into this problem on his computer and the fix works for him)

This patch fixes this more thoroughly than the previous "fix", which
had some bad side effects (namely, for kernel code that wanted to wait for
the scsi scan it would also do an async sync, which would deadlock if you did
it from async context already.. there's a report about that on lkml):
The patch makes the module first wait for all device driver probes, and then it
will wait for the scsi parallel scan to finish.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Tested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 19:40:00 -07:00
Jonathan Corbet
5dd559f020 Trivial: fix a typo in slow-work.h
Fix a comment typo in slow-work.h

...a trivial mistake, but it will mess up kerneldoc if nothing else.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 19:40:00 -07:00
David Howells
5028eaa97d PERCPU: Collect the DECLARE/DEFINE declarations together
Collect the DECLARE/DEFINE declarations together in linux/percpu-defs.h so
that they're in one place, and give them descriptive comments, particularly
the SHARED_ALIGNED variant.

It would be nice to collect these in linux/percpu.h, but that's not possible
without sorting out the severe #include recursion between the x86 arch headers
and the general headers (and possibly other arches too).

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 19:40:00 -07:00
David Howells
9b8de7479d FRV: Fix the section attribute on UP DECLARE_PER_CPU()
In non-SMP mode, the variable section attribute specified by DECLARE_PER_CPU()
does not agree with that specified by DEFINE_PER_CPU().  This means that
architectures that have a small data section references relative to a base
register may throw up linkage errors due to too great a displacement between
where the base register points and the per-CPU variable.

On FRV, the .h declaration says that the variable is in the .sdata section, but
the .c definition says it's actually in the .data section.  The linker throws
up the following errors:

kernel/built-in.o: In function `release_task':
kernel/exit.c:78: relocation truncated to fit: R_FRV_GPREL12 against symbol `per_cpu__process_counts' defined in .data section in kernel/built-in.o
kernel/exit.c:78: relocation truncated to fit: R_FRV_GPREL12 against symbol `per_cpu__process_counts' defined in .data section in kernel/built-in.o

To fix this, DECLARE_PER_CPU() should simply apply the same section attribute
as does DEFINE_PER_CPU().  However, this is made slightly more complex by
virtue of the fact that there are several variants on DEFINE, so these need to
be matched by variants on DECLARE.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 19:39:59 -07:00
David Brownell
6e538aaf50 spi: documentation: emphasise spi_master.setup() semantics
This is a doc-only patch which I hope will reduce the number of
spi_master controller driver patches starting out with a common
implementation bug.

(As in: almost every spi_master driver I see starts out with its
version of this bug.  Sigh.)

It just re-emphasizes that the setup() method may be called for one
device while a transfer is active on another ...  which means that most
driver implementations shouldn't touch any registers.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 13:41:50 -07:00
KAMEZAWA Hiroyuki
e638c13940 memcg: use rcu_dereference to access mm->owner
mm->owner should be accessed with rcu_dereference().

Reported-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 13:41:48 -07:00
dann frazier
4dec302ff7 ipmi: add oem message handling
Enable userspace to receive messages that a BMC transmits using an OEM
medium.  This is used by the HP iLO2.

Based on code originally written by Patrick Schoeller.

Signed-off-by: dann frazier <dannf@hp.com>
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 13:41:48 -07:00
Corey Minyard
40112ae750 ipmi: test for event buffer before using
The IPMI driver would attempt to use the event buffer even if that
didn't exist on the BMC.  This patch modified the IPMI driver to check
for the event buffer's existence before trying to use it.

Signed-off-by: Corey Minyard <minyard@acm.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 13:41:48 -07:00
Magnus Damm
4614e6adaf clocksource: add enable() and disable() callbacks
Add enable() and disable() callbacks for clocksources.

This allows us to put unused clocksources in power save mode.  The
functions clocksource_enable() and clocksource_disable() wrap the
callbacks and are inserted in the timekeeping code to enable before use
and disable after switching to a new clocksource.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 13:41:47 -07:00
Magnus Damm
8e19608e8b clocksource: pass clocksource to read() callback
Pass clocksource pointer to the read() callback for clocksources.  This
allows us to share the callback between multiple instances.

[hugh@veritas.com: fix powerpc build of clocksource pass clocksource mods]
[akpm@linux-foundation.org: cleanup]
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 13:41:47 -07:00
Linus Torvalds
9a41fe3415 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  reiserfs: fix j_last_flush_trans_id type
  fs: Mark get_filesystem_list() as __init function.
  kill vfs_stat_fd / vfs_lstat_fd
  Separate out common fstatat code into vfs_fstatat
  ecryptfs: use memdup_user()
  ncpfs: use memdup_user()
  xfs: use memdup_user()
  sysfs: use memdup_user()
  btrfs: use memdup_user()
  xattr: use memdup_user()
  autofs4: use memchr() in invalid_string()
  Documentation/filesystems: remove out of date reference to BKL being held
  Fix i_mutex vs. readdir handling in nfsd
  fs/compat_ioctl: fix build when !BLOCK
  Fix autofs_expire()
  No need for crossing to mountpoint in audit_tag_tree()
  Safer nfsd_cross_mnt()
  Touch all affected namespaces on propagation of mount
  Fix AUTOFS_DEV_IOCTL_REQUESTER_CMD
2009-04-21 07:56:17 -07:00
Thomas Bogendoerfer
8b9cf76d0f Fix SYSCALL_ALIAS for older MIPS assembler
Older MIPS assembler don't support .set for defining aliases.
Using = works for old and new assembers.

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-21 07:50:58 -07:00
Len Brown
88bea188b8 ACPI: add /sys/firmware/acpi/interrupts/sci_not counter
This counter may prove useful in debugging some
spurious interrupt issues seen in the field.

Signed-off-by: Len Brown <len.brown@intel.com>
2009-04-21 00:35:47 -04:00
Al Viro
be9208dff2 reiserfs: fix j_last_flush_trans_id type
Conversion in commit 600ed41675 had missed
that one, but converted format from %lu to %u.  As the result,
/proc/..../journal got buggered on 64bit boxen.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-20 23:29:41 -04:00
Tetsuo Handa
38e23c95f9 fs: Mark get_filesystem_list() as __init function.
"int get_filesystem_list(char * buf)" is called by only
"static void __init get_fs_names(char *page)".
We can mark get_filesystem_list() as "__init".

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-20 23:02:52 -04:00
Christoph Hellwig
2eae7a1874 kill vfs_stat_fd / vfs_lstat_fd
There's really no reason to keep vfs_stat_fd and vfs_lstat_fd with
Oleg's vfs_fstatat.  Use vfs_fstatat for the few cases having the
directory fd, and switch all others to vfs_stat / vfs_lstat.

Reviewed-by: Christoph Hellwig <hch@lst.de>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-20 23:02:52 -04:00
Oleg Drokin
0112fc2229 Separate out common fstatat code into vfs_fstatat
This is a version incorporating Christoph's suggestion.

Separate out common *fstatat functionality into a single function
instead of duplicating it all over the code.

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-20 23:02:51 -04:00
Linus Torvalds
a939b96ccc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
  PM/Suspend: Introduce two new platform callbacks to avoid breakage
2009-04-20 08:43:06 -07:00
Rafael J. Wysocki
6a7c7eaf71 PM/Suspend: Introduce two new platform callbacks to avoid breakage
Commit 900af0d973 (PM: Change suspend
code ordering) changed the ordering of suspend code in such a way
that the platform .prepare() callback is now executed after the
device drivers' late suspend callbacks have run.  Unfortunately, this
turns out to break ARM platforms that need to talk via I2C to power
control devices during the .prepare() callback.

For this reason introduce two new platform suspend callbacks,
.prepare_late() and .wake(), that will be called just prior to
disabling non-boot CPUs and right after bringing them back on line,
respectively, and use them instead of .prepare() and .finish() for
ACPI suspend.  Make the PM core execute the .prepare() and .finish()
platform suspend callbacks where they were executed previously (that
is, right after calling the regular suspend methods provided by
device drivers and right before executing their regular resume
methods, respectively).

It is not necessary to make analogous changes to the hibernation
code and data structures at the moment, because they are only used
by ACPI platforms.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Len Brown <len.brown@intel.com>
2009-04-19 20:08:42 +02:00
Ralf Baechle
42a17ad276 <linux/seccomp.h> needs to include <linux/errno.h>.
<linux/seccomp.h> uses EINVAL so should include <linux/errno.h>.  This
fixes a build error on 64-bit MIPS if CONFIG_SECCOMP is disabled.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-19 10:47:45 -07:00
Linus Torvalds
74a205a3f1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6:
  UIO: fix specific device driver missing statement for depmod
  Driver core: remove pr_fmt() from dynamic_dev_dbg() printk
  driver core: prevent device_for_each_child from oopsing
  dynamic debug: resurrect old pr_debug() semantics as pr_devel()
  Driver Core: early platform driver
  proc: mounts_poll() make consistent to mdstat_poll
  sysfs: sysfs poll keep the poll rule of regular file.
  driver core: allow non-root users to listen to uevents
  driver core: fix driver_match_device
  sysfs: don't use global workqueue in sysfs_schedule_callback()
2009-04-17 13:53:16 -07:00
Linus Torvalds
dd26bf6d95 Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6: (22 commits)
  WUSB: correct format of wusb_chid sysfs file
  WUSB: fix oops when completing URBs for disconnected devices
  WUSB: disconnect all devices when stopping a WUSB HCD
  USB: whci-hcd: check return value of usb_hcd_link_urb_to_ep()
  USB: whci-hcd: provide a endpoint_reset method
  USB: add reset endpoint operations
  USB device codes for Motorola phone.
  usb-storage: fix mistake in Makefile
  USB: usb-serial ch341: support for DTR/RTS/CTS
  Revert USB: usb-serial ch341: support for DTR/RTS/CTS
  USB: musb: fix possible panic while resuming
  USB: musb: fix isochronous TXDMA (take 2)
  USB: musb: sanitize clearing TXCSR DMA bits (take 2)
  USB: musb: bugfixes for multi-packet TXDMA support
  USB: musb_host, fix ep0 fifo flushing
  USB: usb-storage: augment unusual_devs entry for Simple Tech/Datafab
  USB: musb_host, minor enqueue locking fix (v2)
  USB: fix oops in cdc-wdm in case of malformed descriptors
  USB: qcserial: Add extra device IDs
  USB: option: Add ids for D-Link DWM-652 3.5G modem
  ...
2009-04-17 13:53:00 -07:00
David Vrabel
3444b26afa USB: add reset endpoint operations
Wireless USB endpoint state has a sequence number and a current
window and not just a single toggle bit.  So allow HCDs to provide a
endpoint_reset method and call this or clear the software toggles as
required (after a clear halt, set configuration etc.).

usb_settoggle() and friends are then HCD internal and are moved into
core/hcd.h and all device drivers call usb_reset_endpoint() instead.

If the device endpoint state has been reset (with a clear halt) but
the host endpoint state has not then subsequent data transfers will
not complete. The device will only work again after it is reset or
disconnected.

Signed-off-by: David Vrabel <david.vrabel@csr.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-17 10:50:27 -07:00
Linus Torvalds
91ec65ba33 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: ads7846 - fix unsafe disable_irq
  Input: mainstone-wm97xx - fix condition in pen_up
  Input: pc110pad - remove unused variable dev
  Input: bf54x-keys - remove depreciated IRQF_SAMPLE_RANDOM flag
  Input: ad7877, ad7879 - remove depreciated IRQF_SAMPLE_RANDOM flag
  Input: da9034-ts - make pen {down,up} events more reliable
  Input: da9034-ts - add Bin Yang as co-author of the driver
  Input: atkbd - add forced release keys quirk for Samsung NC20
  Input: atkbd - add forced release keys quirk for Samsung Q45
  Input: gameport - fix attach driver code
  Input: hp_sdc_rtc should depend on serio
  Input: wm97xx - don't specify IRQF_SAMPLE_RANDOM
  Input: ads7846 - introduce platform specific way to synchronize sampling
  Input: remove unnecessary synchronize_rcu() call
  Input: i8042 - add a DMI table for the i8042.reset option
  Input: i8042 - introduce a tougher reset
2009-04-17 10:08:13 -07:00
Linus Torvalds
4d831f53dd Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  kernel/softirq.c: fix sparse warning
  rcu: Make hierarchical RCU less IPI-happy
2009-04-16 17:56:39 -07:00
Jason Baron
7607b1d673 Driver core: remove pr_fmt() from dynamic_dev_dbg() printk
When pr_fmt() was added to the pr_debug() code, we added it not only to the
dynamic_pr_debug() function, but also to the dynamic_dev_dbg() funciton.
However, dev_dbg() doesn't make use of pr_fmt(), so neither should
dynamic_dev_dbg().

Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-16 16:17:11 -07:00
Michael Ellerman
4ccb457966 dynamic debug: resurrect old pr_debug() semantics as pr_devel()
pr_debug() used to produce zero code unless DEBUG was #defined.  This is
now no longer the case in practice[1].

There are places where it's useful to have debugging printks, but we don't
want them to generate any code in production kernels.

So add a new macro, pr_devel(), for _devel_opment, to provide the old
semantics, ie.  if the programmer doesn't explicitly enable debugging, no
code is produced.

[1]: You can turn CONFIG_DYNAMIC_DEBUG off, but it's enabled in at least
     one distro kernel, so it's not really a solution.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Greg Banks <gnb@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-16 16:17:10 -07:00
Magnus Damm
13977091a9 Driver Core: early platform driver
V3 of the early platform driver implementation.

Platform drivers are great for embedded platforms because we can separate
driver configuration from the actual driver.  So base addresses,
interrupts and other configuration can be kept with the processor or board
code, and the platform driver can be reused by many different platforms.

For early devices we have nothing today.  For instance, to configure early
timers and early serial ports we cannot use platform devices.  This
because the setup order during boot.  Timers are needed before the
platform driver core code is available.  The same goes for early printk
support.  Early in this case means before initcalls.

These early drivers today have their configuration either hard coded or
they receive it using some special configuration method.  This is working
quite well, but if we want to support both regular kernel modules and
early devices then we need to have two ways of configuring the same
driver.  A single way would be better.

The early platform driver patch is basically a set of functions that allow
drivers to register themselves and architecture code to locate them and
probe.  Registration happens through early_param().  The time for the
probe is decided by the architecture code.

See Documentation/driver-model/platform.txt for more details.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: David Brownell <david-b@pacbell.net>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-04-16 16:17:10 -07:00
Alan Cox
e3cf95dd6d ata: Report 16/32bit PIO as best we can
The legacy old IDE ioctl API for this is a bit primitive so we try
and map stuff sensibly onto it.

- Set PIO over DMA devices to report 32bit
- Add ability to change the PIO32 settings if the controller permits it
- Add that functionality into the sff drivers
- Add that functionality into the VLB legacy driver
- Turn on the 32bit PIO on the ninja32 and add support there

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-04-16 15:28:23 -04:00
Anton Vorontsov
4124010292 powerpc/5200: Bring the legacy fsl_spi_platform_data hooks back
In commit 364fdbc00f ("spi_mpc83xx:
rework chip selects handling"), I merged activate_cs and deactivate_cs
hooks into cs_control, but I overlooked that mpc52xx_psc_spi driver
is using these hooks too. And that resulted in the following build
failure:

CC      drivers/spi/mpc52xx_psc_spi.o
drivers/spi/mpc52xx_psc_spi.c: In function 'mpc52xx_psc_spi_do_probe':
drivers/spi/mpc52xx_psc_spi.c:398: error: 'struct fsl_spi_platform_data'
has no member named 'activate_cs'
drivers/spi/mpc52xx_psc_spi.c:399: error: 'struct fsl_spi_platform_data'
has no member named 'deactivate_cs'
make[2]: *** [drivers/spi/mpc52xx_psc_spi.o] Error 1

This patch simply adds the legacy hooks back for 2.6.30, and for
2.6.31 we'll convert the driver to ->cs_control.

Reported-by: Subrata Modak <subrata@linux.vnet.ibm.com>
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2009-04-16 09:58:44 -06:00
Dmitry Torokhov
0c387ec88a Merge branch 'next' into for-linus 2009-04-16 08:51:52 -07:00
Chris Mason
35c80d5f40 Add block_write_full_page_endio for passing endio handler
block_write_full_page doesn't allow the caller to control what happens
when the IO is over.  This adds a new call named block_write_full_page_endio
so the buffer head end_io handler can be provided by the caller.

This will be used by the ext3 data=guarded mode to do i_size updates in
a workqueue based end_io handler.  end_buffer_async_write is also
exported so it can be called to do the dirty work of managing page
writeback for the higher level end_io handler.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
Acked-by: Theodore Tso <tytso@mit.edu>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-16 07:47:49 -07:00
Linus Torvalds
cd97824994 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (64 commits)
  phylib: Fix delay argument of schedule_delayed_work
  NET/ixgbe: Fix powering off during shutdown
  NET/e1000e: Fix powering off during shutdown
  NET/e1000: Fix powering off during shutdown
  packet: avoid warnings when high-order page allocation fails
  gianfar: stop send queue before resetting gianfar
  myr10ge: again fix lro_gen_skb() alignment
  declance: convert to net_device_ops
  bfin_mac: convert to net_device_ops
  au1000: convert to net_device_ops
  atarilance: convert to net_device_ops
  a2065: convert to net_device_ops
  ixgbe: update real_num_tx_queues on changing num_rx_queues
  ixgbe: fix tx queue index
  Revert "rose: zero length frame filtering in af_rose.c"
  sfc: Use correct macro to set event bitfield
  sfc: Match calls to netif_napi_add() and netif_napi_del()
  bonding: Remove debug printk
  e1000/e1000: fix compile warning
  ehea: Fix incomplete conversion to net_device_ops
  ...
2009-04-16 07:41:56 -07:00
Linus Torvalds
23da64b471 Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: (28 commits)
  cfq-iosched: add close cooperator code
  cfq-iosched: log responsible 'cfqq' in idle timer arm
  cfq-iosched: tweak kick logic a bit more
  cfq-iosched: no need to save interrupts in cfq_kick_queue()
  brd: fix cacheflushing
  brd: support barriers
  swap: Remove code handling bio_alloc failure with __GFP_WAIT
  gfs2: Remove code handling bio_alloc failure with __GFP_WAIT
  ext4: Remove code handling bio_alloc failure with __GFP_WAIT
  dio: Remove code handling bio_alloc failure with __GFP_WAIT
  block: Remove code handling bio_alloc failure with __GFP_WAIT
  bio: add documentation to bio_alloc()
  splice: add helpers for locking pipe inode
  splice: remove generic_file_splice_write_nolock()
  ocfs2: fix i_mutex locking in ocfs2_splice_to_file()
  splice: fix i_mutex locking in generic_splice_write()
  splice: remove i_mutex locking in splice_from_pipe()
  splice: split up __splice_from_pipe()
  block: fix SG_IO to return a proper error value
  cfq-iosched: don't delay queue kick for a merged request
  ...
2009-04-15 09:03:47 -07:00
Linus Torvalds
a23c218bd3 Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
  powerpc: pseries/dtl.c should include asm/firmware.h
  powerpc: Fix data-corrupting bug in __futex_atomic_op
  powerpc/pseries: Set error_state to pci_channel_io_normal in eeh_report_reset()
  powerpc: Allow 256kB pages with SHMEM
  powerpc: Document new FSL I2C bindings and cleanup
  powerpc/mm: Fix compile warning
  powerpc/85xx: TQM8548: update defconfig
  powerpc/85xx: TQM8548: use proper phy-handles for enet2 and enet3
  powerpc/85xx: TQM85xx: correct address of LM75 I2C device nodes
  powerpc: Add support for early tlbilx opcode
  powerpc: Fix tlbilx opcode
2009-04-15 08:42:40 -07:00
Miklos Szeredi
61e0d47c33 splice: add helpers for locking pipe inode
There are lots of sequences like this, especially in splice code:

	if (pipe->inode)
		mutex_lock(&pipe->inode->i_mutex);
	/* do something */
	if (pipe->inode)
		mutex_unlock(&pipe->inode->i_mutex);

so introduce helpers which do the conditional locking and unlocking.
Also replace the inode_double_lock() call with a pipe_double_lock()
helper to avoid spreading the use of this functionality beyond the
pipe code.

This patch is just a cleanup, and should cause no behavioral changes.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-15 12:10:12 +02:00
Miklos Szeredi
f8cc774ce4 splice: remove generic_file_splice_write_nolock()
Remove the now unused generic_file_splice_write_nolock() function.
It's conceptually broken anyway, because splice may need to wait for
pipe events so holding locks across the whole operation is wrong.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-15 12:10:12 +02:00
Miklos Szeredi
328eaaba4e ocfs2: fix i_mutex locking in ocfs2_splice_to_file()
Rearrange locking of i_mutex on destination and call to
ocfs2_rw_lock() so locks are only held while buffers are copied with
the pipe_to_file() actor, and not while waiting for more data on the
pipe.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-15 12:10:12 +02:00
Miklos Szeredi
b3c2d2ddd6 splice: split up __splice_from_pipe()
Split up __splice_from_pipe() into four helper functions:

  splice_from_pipe_begin()
  splice_from_pipe_next()
  splice_from_pipe_feed()
  splice_from_pipe_end()

splice_from_pipe_next() will wait (if necessary) for more buffers to
be added to the pipe.  splice_from_pipe_feed() will feed the buffers
to the supplied actor and return when there's no more data available
(or if all of the requested data has been copied).

This is necessary so that implementations can do locking around the
non-waiting splice_from_pipe_feed().

This patch should not cause any change in behavior.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-15 12:10:11 +02:00
Jens Axboe
48e70bc18a Document and move the various READ/WRITE types
It's a somewhat twisty maze of hints and behavioural modifiers, try
and clear it up a bit with some documentation.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-15 08:28:10 +02:00
Christoph Hellwig
8f3d8ba20e block: move bio list helpers into bio.h
It's used by DM and MD and generally useful, so move the bio list
helpers into bio.h.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-04-15 08:28:09 +02:00
Linus Torvalds
610f26e751 Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  lockdep: warn about lockdep disabling after kernel taint, fix
2009-04-14 10:12:31 -07:00
Leandro Dorileo
78c5b82ee6 tty: Update some of the USB kernel doc
Updates some usb_serial_port members documentation.

Signed-off-by: Leandro Dorileo <ldorileo@gmail.com>
Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-14 08:48:57 -07:00
Theodore Ts'o
38d726d153 jbd: use SWRITE_SYNC_PLUG when writing synchronous revoke records
The revoke records must be written using the same way as the rest of
the blocks during the commit process; that is, either marked as
synchronous writes or as asynchornous writes.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-14 10:10:47 -04:00
Theodore Ts'o
67c457a8c3 jbd2: use SWRITE_SYNC_PLUG when writing synchronous revoke records
The revoke records must be written using the same way as the rest of
the blocks during the commit process; that is, either marked as
synchronous writes or as asynchornous writes.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-04-14 07:50:56 -04:00
Paul E. McKenney
ef631b0ca0 rcu: Make hierarchical RCU less IPI-happy
This patch fixes a hierarchical-RCU performance bug located by Anton
Blanchard.  The problem stems from a misguided attempt to provide a
work-around for jiffies-counter failure.  This work-around uses a per-CPU
n_rcu_pending counter, which is incremented on each call to rcu_pending(),
which in turn is called from each scheduling-clock interrupt.  Each CPU
then treats this counter as a surrogate for the jiffies counter, so
that if the jiffies counter fails to advance, the per-CPU n_rcu_pending
counter will cause RCU to invoke force_quiescent_state(), which in turn
will (among other things) send resched IPIs to CPUs that have thus far
failed to pass through an RCU quiescent state.

Unfortunately, each CPU resets only its own counter after sending a
batch of IPIs.  This means that the other CPUs will also (needlessly)
send -another- round of IPIs, for a full N-squared set of IPIs in the
worst case every three scheduler-clock ticks until the grace period
finally ends.  It is not reasonable for a given CPU to reset each and
every n_rcu_pending for all the other CPUs, so this patch instead simply
disables the jiffies-counter "training wheels", thus eliminating the
excessive IPIs.

Note that the jiffies-counter IPIs do not have this problem due to
the fact that the jiffies counter is global, so that the CPU sending
the IPIs can easily reset things, thus preventing the other CPUs from
sending redundant IPIs.

Note also that the n_rcu_pending counter remains, as it will continue to
be used for tracing.  It may also see use to update the jiffies counter,
should an appropriate kick-the-jiffies-counter API appear.

Located-by: Anton Blanchard <anton@au1.ibm.com>
Tested-by: Anton Blanchard <anton@au1.ibm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: anton@samba.org
Cc: akpm@linux-foundation.org
Cc: dipankar@in.ibm.com
Cc: manfred@colorfullife.com
Cc: cl@linux-foundation.org
Cc: josht@linux.vnet.ibm.com
Cc: schamp@sgi.com
Cc: niv@us.ibm.com
Cc: dvhltc@us.ibm.com
Cc: ego@in.ibm.com
Cc: laijs@cn.fujitsu.com
Cc: rostedt@goodmis.org
Cc: peterz@infradead.org
Cc: penberg@cs.helsinki.fi
Cc: andi@firstfloor.org
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
LKML-Reference: <12396834793575-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-04-14 11:31:50 +02:00