Commit Graph

166668 Commits

Author SHA1 Message Date
Linus Torvalds bfebb14063 Merge branch 'writeback' of git://git.kernel.dk/linux-2.6-block
* 'writeback' of git://git.kernel.dk/linux-2.6-block:
  writeback: pass in super_block to bdi_start_writeback()
2009-09-26 10:11:13 -07:00
Linus Torvalds 07e2e6ba27 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:
  cifs: fix locking and list handling code in cifs_open and its helper
  [CIFS] Remove build warning
  cifs: fix problems with last two commits
  [CIFS] Fix build break when keys support turned off
  cifs: eliminate cifs_init_private
  cifs: convert oplock breaks to use slow_work facility (try #4)
  cifs: have cifsFileInfo hold an extra inode reference
  cifs: take read lock on GlobalSMBSes_lock in is_valid_oplock_break
  cifs: remove cifsInodeInfo.oplockPending flag
  cifs: fix oplock request handling in posix codepath
  [CIFS] Re-enable Lanman security
2009-09-26 10:10:35 -07:00
Linus Torvalds d8f654ef6a 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:
  at91_can: Forgotten git 'add' of at91_can.c
  TI Davinci EMAC: Fix in vector definition for EMAC_VERSION_2
  ax25: Fix ax25_cb refcounting in ax25_ctl_ioctl
  virtio_net: Check for room in the vq before adding buffer
  virtio_net: avoid (most) NETDEV_TX_BUSY by stopping queue early.
  virtio_net: formalize skb_vnet_hdr
  virtio_net: don't free buffers in xmit ring
  virtio_net: return NETDEV_TX_BUSY instead of queueing an extra skb.
  virtio_net: skb_orphan() and nf_reset() in xmit path.
2009-09-26 10:09:39 -07:00
Linus Torvalds 052a0cf6f8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
  sparc64: vio: Kill BUILD_BUG_ON() in vio_dring_avail().

Trivial conflict in arch/sparc/include/asm/vio.h due to David removing
the whole messy BUG_ON that was confused.
2009-09-26 10:08:23 -07:00
Nicolas Pitre 9e6ec39bec make Linux bootable on ARM again
Commit 200b812d00 "Clear the exclusive monitor when returning from an
exception" broke the vast majority of ARM systems in the wild which are
still pre ARMv6.  The kernel is crashing on the first occurrence of an
exception due to the removal of the actual return instruction for them.
Let's add it back.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-26 10:06:53 -07:00
Michael Hennerich a7998cecf5 backlight: new driver for ADP5520/ADP5501 MFD PMICs
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2009-09-26 16:48:08 +01:00
Henrique de Moraes Holschuh 89dfc28ccb backlight: extend event support to also support poll()
Extend the backlight event support to also allow the use of
poll()/select() on actual_brightness.

We already have the entire event hookup anyway, adding a single
function call in one line to get functionality like that is a really
good deal.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2009-09-26 16:48:06 +01:00
Bjorn Helgaas e96c9284bd ACPI: i2c-scmi: don't use acpi_device_uid()
We recently removed the acpi_device_uid() interface because nobody
used it.  I don't think it's essential here either.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-26 01:42:07 -04:00
Len Brown 2b474ad847 Merge branch 'thinkpad-2.6.32-part2' into release 2009-09-26 01:08:55 -04:00
Len Brown ea26105157 Merge branch 'bjorn-HID' into release 2009-09-26 01:08:43 -04:00
Jens Axboe a72bfd4dea writeback: pass in super_block to bdi_start_writeback()
Sometimes we only want to write pages from a specific super_block,
so allow that to be passed in.

This fixes a problem with commit 56a131dcf7
causing writeback on all super_blocks on a bdi, where we only really
want to sync a specific sb from writeback_inodes_sb().

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-26 00:10:40 +02:00
David S. Miller 99c4a6344f at91_can: Forgotten git 'add' of at91_can.c
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-25 13:43:54 -07:00
Sriram 43c2ed8e9e TI Davinci EMAC: Fix in vector definition for EMAC_VERSION_2
In the emac_poll function when looking for interrupt status masks
correct definition must be chosen based on EMAC_VERSION(the bit
mask has changed from version 1 to version 2).

Signed-off-by: Sriram <srk@ti.com>
Acked-by: Chaithrika U S <chaithrika@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-25 13:43:49 -07:00
Jarek Poplawski c0181d420c ax25: Fix ax25_cb refcounting in ax25_ctl_ioctl
Use ax25_cb_put after ax25_find_cb in ax25_ctl_ioctl.

Reported-by: Bernard Pidoux F6BVP <f6bvp@free.fr>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Reviewed-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-25 13:43:48 -07:00
Bjorn Helgaas 57f3674f5e ACPI: simplify building device HID/CID list
Minor code cleanup, no functional change.  Instead of remembering
what HIDs & CIDs to add later, just add them immediately.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 15:09:49 -04:00
Bjorn Helgaas 6622d8cee7 ACPI: remove acpi_device_uid() and related stuff
Nobody uses acpi_device_uid(), so this patch removes it.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 15:09:49 -04:00
Bjorn Helgaas 1131b938f0 ACPI: remove acpi_device.flags.hardware_id
Every acpi_device has at least one ID (if there's no _HID or _CID, we
give it a synthetic or default ID).  So there's no longer a need to
check whether an ID exists; we can just use it.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 15:09:48 -04:00
Bjorn Helgaas b2972f8750 ACPI: remove acpi_device.flags.compatible_ids
We now keep a single list of IDs that includes both the _HID and any
_CIDs.  We no longer need to keep track of whether the device has a _CID.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 15:09:47 -04:00
Bjorn Helgaas 7f47fa6c2f ACPI: maintain a single list of _HID and _CID IDs
There's no need to treat _HID and _CID differently.  Keeping them in
a single list makes code that uses the IDs a little simpler because it
can just traverse the list rather than checking "do we have a HID?",
"do we have any CIDs?"

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Reviewed-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 15:09:31 -04:00
Bjorn Helgaas b1fbfb2ae8 ACPI: make sure every acpi_device has an ID
This makes sure every acpi_device has at least one ID.  If we build an
acpi_device for a namespace node with no _HID or _CID, we sometimes
synthesize an ID like "LNXCPU" or "LNXVIDEO".  If we don't even have
that, give it a default "device" ID.

Note that this means things like:
    /sys/devices/LNXSYSTM:00/LNXSYBUS:00/HWP0001:00/HWP0002:04/device:00
(a PCI slot SxFy device) will have "hid" and "modprobe" entries, where
they didn't before.  These aren't very useful (a HID of "device" doesn't
tell you what *kind* of device it is, so it doesn't help find a driver),
but I don't think they're harmful.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:26:02 -04:00
Bjorn Helgaas ea8d82fd31 ACPI: use acpi_device_hid() when possible
Use acpi_device_hid() rather than accessing acpi_device.pnp.hardware_id
directly.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:25:52 -04:00
Bjorn Helgaas 78b8e141f8 ACPI: fix synthetic HID for \_SB_
This makes \_SB_ show up as /sys/devices/LNXSYSTM:00/LNXSYBUS:00
rather than "device:00".  This has been broken for a loooong time
(at least since 2.6.13) because device->parent is an acpi_device
pointer, not a handle.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:25:29 -04:00
Bjorn Helgaas e3b87f8a9d ACPI: handle re-enumeration, when acpi_devices might already exist
acpi_bus_scan() traverses the namespace to enumerate devices and uses
acpi_add_single_object() to create acpi_devices.  When the platform
notifies us of a hot-plug event, we need to traverse part of the namespace
again to figure out what appeared or disappeared.  (We don't yet call
acpi_bus_scan() during hot-plug, but I plan to do that in the future.)

This patch makes acpi_add_single_object() notice when we already have
an acpi_device, so we don't need to make a new one.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:32 -04:00
Bjorn Helgaas 778cbc1d3a ACPI: factor out device type and status checking
This patch adds acpi_bus_type_and_status(), which determines the type
of the object and whether we want to build an acpi_device for it.  If
it is acpi_device-worthy, it returns the type and the device's current
status.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:31 -04:00
Bjorn Helgaas 402ac53614 ACPI: add acpi_bus_get_status_handle()
Add acpi_bus_get_status_handle() so we can get the status of a namespace
object before building a struct acpi_device.

This removes a use of "device->flags.dynamic_status", a cached indicator of
whether _STA exists.  It seems simpler and more reliable to just evaluate
_STA and catch AE_NOT_FOUND errors.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:30 -04:00
Bjorn Helgaas 51a85faf2d ACPI: use acpi_walk_namespace() to enumerate devices
acpi_bus_scan() currently walks the namespace manually.  This patch changes
it to use acpi_walk_namespace() instead.

Besides removing some complicated code, this means we take advantage of the
namespace locking done by acpi_walk_namespace().  The locking isn't so
important at boot-time, but I hope to eventually use this same path to
handle hot-addition of devices, when it will be important.

Note that acpi_walk_namespace() does not actually visit the starting node
first, so we need to do that by hand first.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:30 -04:00
Bjorn Helgaas 859ac9a4be ACPI: identify device tree root by null parent pointer, not ACPI_BUS_TYPE
We can identify the root of the ACPI device tree by the fact that it
has no parent.  This is simpler than passing around ACPI_BUS_TYPE_SYSTEM
and will help remove special treatment of the device tree root.

Currently, we add the root by hand with ACPI_BUS_TYPE_SYSTEM.  If we
traverse the tree treating the root as just another device and use
acpi_get_type(), the root shows up as ACPI_TYPE_DEVICE.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:29 -04:00
Bjorn Helgaas adc08e2035 ACPI: enumerate namespace before adding functional fixed hardware devices
This patch changes the order so we enumerate in the "root, namespace,
functional fixed" order instead of the "root, functional fixed, namespace"
order.  When I change acpi_bus_scan() to use acpi_walk_namespace(), it
will use the former order, so this patch isolates the order change for
bisectability.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:29 -04:00
Bjorn Helgaas 8e029bf0a6 ACPI: convert acpi_bus_scan() to operate on an acpi_handle
This patch changes acpi_bus_scan() to take an acpi_handle rather than an
acpi_device pointer.  I plan to use acpi_bus_scan() in the hotplug path,
and I'd rather not assume that notifications only go to nodes that already
have acpi_devices.

This will also help remove the special case for adding the root node.  We
currently add the root by hand before acpi_bus_scan(), but using a handle
here means we can start the acpi_bus_scan() directly with the root even
though it doesn't have an acpi_device yet.

Note that acpi_bus_scan() currently adds and/or starts the *children* of
its device argument.  It doesn't do anything with the device itself.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:28 -04:00
Bjorn Helgaas 5c478f499c ACPI: add acpi_bus_get_parent() and remove "parent" arguments
This patch adds acpi_bus_get_parent(), which ascends the namespace until
it finds a parent with an acpi_device.

Then we use acpi_bus_get_parent() in acpi_add_single_object(), so callers
don't have to figure out or keep track of the parent acpi_device.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:28 -04:00
Bjorn Helgaas 77c24888b7 ACPI: remove unnecessary argument checking
acpi_add_single_object() is static, and all callers supply a valid "child"
argument, so we don't need to check it.  This patch also remove some
unnecessary initializations.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:27 -04:00
Bjorn Helgaas c7bcb4e98a ACPI: remove redundant "type" arguments
We now save the ACPI bus "device_type" in the acpi_device structure, so
we don't need to pass it around explicitly anymore.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:26 -04:00
Bjorn Helgaas bc3b07726a ACPI: remove acpi_device_set_context() "type" argument
We only pass the "type" to acpi_device_set_context() so we know whether
the device has a handle to which we can attach the acpi_device pointer.
But it's safer to just check for the handle directly, since it's in the
acpi_device already.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:26 -04:00
Bjorn Helgaas ccba2a36d7 ACPI: use device_type rather than comparing HID
Check the acpi_device device_type rather than the HID.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:25 -04:00
Bjorn Helgaas caaa6efb3d ACPI: save device_type in acpi_device
Most uses of the ACPI bus device_type (ACPI_BUS_TYPE_DEVICE,
ACPI_BUS_TYPE_POWER, etc) are during device initialization, but
we do need it later for notify handler installation, since that
is different for fixed hardware devices vs. namespace devices.

This patch saves the device_type in the acpi_device structure,
so we can check that rather than comparing against the _HID string.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:25 -04:00
Bjorn Helgaas 66b7ed40aa ACPI: remove redundant "handle" and "parent" arguments
In several cases, functions take handle and parent device pointers in
addition to acpi_device pointers.  But the acpi_device structure contains
both the handle and the parent pointer, so it's pointless and error-prone
to pass them all.  This patch removes the unnecessary "handle" and "parent"
arguments.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:24 -04:00
Bjorn Helgaas e8b945c9c1 ACPI: remove unused acpi_bus_scan_fixed() argument
We never use the "root" argument, so just remove it.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:24 -04:00
Bjorn Helgaas 29aaefa68f ACPI: add debug for device addition
Add debug output for adding an ACPI device.  Enable this with
"acpi.debug_layer=0x00010000" (ACPI_BUS_COMPONENT).

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:23 -04:00
Bjorn Helgaas b24715027a ACPICA: fixup after acpi_get_object_info() change
Commit 15b8dd53f5 changed info->hardware_id from a static array to
a pointer.  If hardware_id is non-NULL, it points to a NULL-terminated
string, so we don't need to terminate it explicitly.  However, it may
be NULL; in that case, we *can't* add a NULL terminator.

This causes a NULL pointer dereference oops for devices without _HID.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
CC: Lin Ming <ming.m.lin@intel.com>
CC: Bob Moore <robert.moore@intel.com>
CC: Gary Hade <garyhade@us.ibm.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-25 14:24:22 -04:00
David S. Miller a91eba5b9d Merge branch 'master' of ssh://master.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-davem 2009-09-25 11:09:08 -07:00
Jeff Layton 3321b791b2 cifs: fix locking and list handling code in cifs_open and its helper
The patch to remove cifs_init_private introduced a locking imbalance. It
didn't remove the leftover list addition code and the unlocking in that
function. cifs_new_fileinfo does the list addition now, so there should
be no need to do it outside of that function.

pCifsInode will never be NULL, so we don't need to check for that. This
patch also gets rid of the ugly locking and unlocking across function
calls.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Steve French <sfrench@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2009-09-25 17:59:31 +00:00
Sam Ravnborg de078ef55c alpha: fix build after vmlinux.lds.S cleanup
Add include to get missing THREAD_SIZE definition

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Tim Abbott <tabbott@ksplice.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
2009-09-25 19:54:56 +02:00
Manuel Lauss d71789b6fa mips: fix build of vmlinux.lds
Commit 51b563fc93 ("arm, cris, mips,
sparc, powerpc, um, xtensa: fix build with bash 4.0") removed a few
CPPFLAGS with vital include paths necessary to build vmlinux.lds
on MIPS, and moved the calculation of the 'jiffies' symbol
directly to vmlinux.lds.S but forgot to change make ifdef/... to
cpp macros.

Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
[sam: moved assignment of CPPFLAGS arch/mips/kernel/Makefile]
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Dmitri Vorobiev <dmitri.vorobiev@movial.com>
2009-09-25 19:49:27 +02:00
Linus Torvalds 6d7f18f6ea Merge branch 'writeback' of git://git.kernel.dk/linux-2.6-block
* 'writeback' of git://git.kernel.dk/linux-2.6-block:
  writeback: writeback_inodes_sb() should use bdi_start_writeback()
  writeback: don't delay inodes redirtied by a fast dirtier
  writeback: make the super_block pinning more efficient
  writeback: don't resort for a single super_block in move_expired_inodes()
  writeback: move inodes from one super_block together
  writeback: get rid to incorrect references to pdflush in comments
  writeback: improve readability of the wb_writeback() continue/break logic
  writeback: cleanup writeback_single_inode()
  writeback: kupdate writeback shall not stop when more io is possible
  writeback: stop background writeback when below background threshold
  writeback: balance_dirty_pages() shall write more than dirtied pages
  fs: Fix busyloop in wb_writeback()
2009-09-25 09:27:30 -07:00
Jens Axboe 56a131dcf7 writeback: writeback_inodes_sb() should use bdi_start_writeback()
Pointless to iterate other devices looking for a super, when
we have a bdi mapping.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-25 18:08:26 +02:00
Wu Fengguang b3af9468ae writeback: don't delay inodes redirtied by a fast dirtier
Debug traces show that in per-bdi writeback, the inode under writeback
almost always get redirtied by a busy dirtier.  We used to call
redirty_tail() in this case, which could delay inode for up to 30s.

This is unacceptable because it now happens so frequently for plain cp/dd,
that the accumulated delays could make writeback of big files very slow.

So let's distinguish between data redirty and metadata only redirty.
The first one is caused by a busy dirtier, while the latter one could
happen in XFS, NFS, etc. when they are doing delalloc or updating isize.

The inode being busy dirtied will now be requeued for next io, while
the inode being redirtied by fs will continue to be delayed to avoid
repeated IO.

CC: Jan Kara <jack@suse.cz>
CC: Theodore Ts'o <tytso@mit.edu>
CC: Dave Chinner <david@fromorbit.com>
CC: Chris Mason <chris.mason@oracle.com>
CC: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-25 18:08:26 +02:00
Jens Axboe 9ecc2738ac writeback: make the super_block pinning more efficient
Currently we pin the inode->i_sb for every single inode. This
increases cache traffic on sb->s_umount sem. Lets instead
cache the inode sb pin state and keep the super_block pinned
for as long as keep writing out inodes from the same
super_block.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-25 18:08:26 +02:00
Jens Axboe cf137307cd writeback: don't resort for a single super_block in move_expired_inodes()
If we only moved inodes from a single super_block to the temporary
list, there's no point in doing a resort for multiple super_blocks.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-25 18:08:26 +02:00
Shaohua Li 5c03449d34 writeback: move inodes from one super_block together
__mark_inode_dirty adds inode to wb dirty list in random order. If a disk has
several partitions, writeback might keep spindle moving between partitions.
To reduce the move, better write big chunk of one partition and then move to
another. Inodes from one fs usually are in one partion, so idealy move indoes
from one fs together should reduce spindle move. This patch tries to address
this. Before per-bdi writeback is added, the behavior is write indoes
from one fs first and then another, so the patch restores previous behavior.
The loop in the patch is a bit ugly, should we add a dirty list for each
superblock in bdi_writeback?

Test in a two partition disk with attached fio script shows about 3% ~ 6%
improvement.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-25 18:08:25 +02:00
Jens Axboe 5b0830cb90 writeback: get rid to incorrect references to pdflush in comments
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-25 18:08:25 +02:00