Arjan van de Ven [Wed, 30 Sep 2009 15:07:54 +0000 (17:07 +0200)]
x86: Provide an alternative() based cmpxchg64()
cmpxchg64() today generates, to quote Linus, "barf bag" code.
cmpxchg64() is about to get used in the scheduler to fix a bug there,
but it's a prerequisite that cmpxchg64() first be made non-sucking.
This patch turns cmpxchg64() into an efficient implementation that
uses the alternative() mechanism to just use the raw instruction on
all modern systems.
Note: the fallback is NOT smp safe, just like the current fallback
is not SMP safe. (Interested parties with i486 based SMP systems
are welcome to submit fix patches for that.)
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
[ fixed asm constraint bug ] Fixed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: John Stultz <johnstul@us.ibm.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090930170754.0886ff2e@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
.. duplicated by merging the same fix twice, for details see commit 0d9df2515dbceb67d343c0f10fd3ff218380d524 ("Merge
git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fixes")
tty: make the kref destructor occur asynchronously
Due to tty release routines run in a workqueue now, error like the
following will be reported while booting:
INIT open /dev/console Input/output error
It also causes hibernation regression to appear as reported at
http://bugzilla.kernel.org/show_bug.cgi?id=14229
The reason is that now there's latency issue with closing, but when
we open a "closing not finished" tty, -EIO will be returned.
Fix it as per the following Alan's suggestion:
Fun but it's actually not a bug and the fix is wrong in itself as
the port may be closing but not yet being destructed, in which case
it seems to do the wrong thing. Opening a tty that is closing (and
could be closing for long periods) is supposed to return -EIO.
I suspect a better way to deal with this and keep the old console
timing is to split tty->shutdown into two functions.
tty->shutdown() - called synchronously just before we dump the tty
onto the waitqueue for destruction
tty->cleanup() - called when the destructor runs.
We would then do the shutdown part which can occur in IRQ context
fine, before queueing the rest of the release (from tty->magic = 0
... the end) to occur asynchronously
The USB update in -next would then need a call like
if (tty->cleanup)
tty->cleanup(tty);
at the top of the async function and the USB shutdown to be split
between shutdown and cleanup as the USB resource cleanup and final
tidy cannot occur synchronously as it needs to sleep.
In other words the logic becomes
final kref put
make object unfindable
async
clean it up
Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
[ rjw: Rebased on top of 2.6.31-git, reworked the changelog. ] Signed-off-by: "Rafael J. Wysocki" <rjw@sisk.pl>
[ Changed serial naming to match new rules, dropped tty_shutdown as per
comments from Alan Stern - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 3d5b6fb47a8e68fa311ca2c3447e7f8a7c3a9cf3 ("ACPI: Kill overly
verbose "power state" log messages") removed the actual use of this
variable, but didn't remove the variable itself, resulting in build
warnings like
drivers/acpi/processor_idle.c: In function ‘acpi_processor_power_init’:
drivers/acpi/processor_idle.c:1169: warning: unused variable ‘i’
Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Fix hwpoison code related build failure on 32-bit NUMAQ
I was recently lucky enough to get a 64-CPU system, so my kernel log
ends up with 64 lines like:
ACPI: CPU0 (power states: C1[C1] C2[C3])
This is pretty useless clutter because this info is already available
after boot from both /sys/devices/system/cpu/cpu*/cpuidle/state?/ as
well as /proc/acpi/processor/CPU*/power.
So just delete the code that prints the C-states in processor_idle.c.
Signed-off-by: Roland Dreier <rolandd@cisco.com> Signed-off-by: Len Brown <len.brown@intel.com>
x86: Fix hwpoison code related build failure on 32-bit NUMAQ
This build failure triggers:
In file included from include/linux/suspend.h:8,
from arch/x86/kernel/asm-offsets_32.c:11,
from arch/x86/kernel/asm-offsets.c:2:
include/linux/mm.h:503:2: error: #error SECTIONS_WIDTH+NODES_WIDTH+ZONES_WIDTH > BITS_PER_LONG - NR_PAGEFLAGS
Because due to the hwpoison page flag we ran out of page
flags on 32-bit.
Dont turn on hwpoison on 32-bit NUMA (it's rare in any
case).
Also clean up the Kconfig dependencies in the generic MM
code by introducing ARCH_SUPPORTS_MEMORY_FAILURE.
Jean Delvare [Tue, 8 Sep 2009 13:31:46 +0000 (15:31 +0200)]
ACPI: Clarify resource conflict message
The message "ACPI: Device needs an ACPI driver" is misleading. The
device _may_ need an ACPI driver, if the BIOS implemented a custom
API for the device in question (which, AFAIK, can't be checked.) If
not, then either a generic ACPI driver may be used (for example
"thermal"), or nothing can be done (other than a white list).
I propose to reword the message to:
ACPI: If an ACPI driver is available for this device, you should use
it instead of the native driver
which I think is more correct. Comments and suggestions welcome.
I also added a message warning about possible problems and system
instability when users pass acpi_enforce_resources=lax, as suggested
by Len.
Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: Thomas Renninger <trenn@suse.de> Cc: Alan Jenkins <sourcejedi.lkml@googlemail.com> Signed-off-by: Len Brown <len.brown@intel.com>
thinkpad-acpi: fix CONFIG_THINKPAD_ACPI_HOTKEY_POLL build problem
Fix this problem when CONFIG_THINKPAD_ACPI_HOTKEY_POLL is undefined:
CHECK drivers/platform/x86/thinkpad_acpi.c
drivers/platform/x86/thinkpad_acpi.c:1968:21: error: not an lvalue
CC [M] drivers/platform/x86/thinkpad_acpi.o
drivers/platform/x86/thinkpad_acpi.c: In function 'tpacpi_hotkey_driver_mask_set':
drivers/platform/x86/thinkpad_acpi.c:1968: error: lvalue required as left operand of assignment
Reported-by: Noah Dain <noahdain@gmail.com> Reported-by: Audrius Kazukauskas <audrius@neutrino.lt> Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Signed-off-by: Len Brown <len.brown@intel.com>
Merge branch 'for-linus' of git://git.o-hand.com/linux-rpurdie-backlight
* 'for-linus' of git://git.o-hand.com/linux-rpurdie-backlight:
backlight: new driver for ADP5520/ADP5501 MFD PMICs
backlight: extend event support to also support poll()
backlight/eeepc-laptop: Update the backlight state when we change brightness
backlight/acpi: Update the backlight state when we change brightness
backlight: Allow drivers to update the core, and generate events on changes
backlight: switch to da903x driver to dev_pm_ops
backlight: Add support for the Avionic Design Xanthos backlight device.
backlight: spi driver for LMS283GF05 LCD
backlight: move hp680-bl's probe function to .devinit.text
backlight: Add support for new Apple machines.
backlight: mbp_nvidia_bl: add support for MacBookAir 1,1
backlight: Add WM831x backlight driver
Trivial conflicts due to '#ifdef CONFIG_PM' differences in
drivers/video/backlight/da903x_bl.c
* remove asm/atomic.h inclusion from kref.h -- not needed, linux/types.h
is enough for atomic_t
* remove linux/kref.h inclusion from files which do not need it.
Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
clocksource: Resume clocksource without taking the clocksource mutex
Merge branch 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
modules, tracing: Remove stale struct marker signature from module_layout()
tracing/workqueue: Use %pf in workqueue trace events
tracing: Fix a comment and a trivial format issue in tracepoint.h
tracing: Fix failure path in ftrace_regex_open()
tracing: Fix failure path in ftrace_graph_write()
tracing: Check the return value of trace_get_user()
tracing: Fix off-by-one in trace_get_user()
Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: Remove redundant non-NUMA topology functions
x86: early_printk: Protect against using the same device twice
x86: Reduce verbosity of "PAT enabled" kernel message
x86: Reduce verbosity of "TSC is reliable" message
x86: mce: Use safer ways to access MCE registers
x86: mce, inject: Use real inject-msg in raise_local
x86: mce: Fix thermal throttling message storm
x86: mce: Clean up thermal throttling state tracking code
x86: split NX setup into separate file to limit unstack-protected code
xen: check EFER for NX before setting up GDT mapping
x86: Cleanup linker script using new linker script macros.
x86: Use section .data.page_aligned for the idt_table.
x86: convert to use __HEAD and HEAD_TEXT macros.
x86: convert compressed loader to use __HEAD and HEAD_TEXT macros.
x86: fix fragile computation of vsyscall address
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: (32 commits)
ACPI: i2c-scmi: don't use acpi_device_uid()
ACPI: simplify building device HID/CID list
ACPI: remove acpi_device_uid() and related stuff
ACPI: remove acpi_device.flags.hardware_id
ACPI: remove acpi_device.flags.compatible_ids
ACPI: maintain a single list of _HID and _CID IDs
ACPI: make sure every acpi_device has an ID
ACPI: use acpi_device_hid() when possible
ACPI: fix synthetic HID for \_SB_
ACPI: handle re-enumeration, when acpi_devices might already exist
ACPI: factor out device type and status checking
ACPI: add acpi_bus_get_status_handle()
ACPI: use acpi_walk_namespace() to enumerate devices
ACPI: identify device tree root by null parent pointer, not ACPI_BUS_TYPE
ACPI: enumerate namespace before adding functional fixed hardware devices
ACPI: convert acpi_bus_scan() to operate on an acpi_handle
ACPI: add acpi_bus_get_parent() and remove "parent" arguments
ACPI: remove unnecessary argument checking
ACPI: remove redundant "type" arguments
ACPI: remove acpi_device_set_context() "type" argument
...
* 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
* 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.
Nicolas Pitre [Fri, 25 Sep 2009 20:28:02 +0000 (16:28 -0400)]
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.
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 56a131dcf7ed36c3c6e36bea448b674ea85ed5bb
causing writeback on all super_blocks on a bdi, where we only really
want to sync a specific sb from writeback_inodes_sb().
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
Commit 15b8dd53f5ffa 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>
Jeff Layton [Fri, 25 Sep 2009 13:53:37 +0000 (09:53 -0400)]
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>
Sam Ravnborg [Fri, 25 Sep 2009 17:53:43 +0000 (19:53 +0200)]
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>
Manuel Lauss [Thu, 24 Sep 2009 19:44:24 +0000 (21:44 +0200)]
mips: fix build of vmlinux.lds
Commit 51b563fc93c8cb5bff1d67a0a71c374e4a4ea049 ("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>
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()
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>
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.
Shaohua Li [Thu, 24 Sep 2009 12:42:33 +0000 (14:42 +0200)]
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.
Make the if-else straight in writeback_single_inode().
No behavior change.
Cc: Jan Kara <jack@suse.cz> Cc: Michael Rubin <mrubin@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
writeback: kupdate writeback shall not stop when more io is possible
Fix the kupdate case, which disregards wbc.more_io and stop writeback
prematurely even when there are more inodes to be synced.
wbc.more_io should always be respected.
Also remove the pages_skipped check. It will set when some page(s) of some
inode(s) cannot be written for now. Such inodes will be delayed for a while.
This variable has nothing to do with whether there are other writeable inodes.
CC: Jan Kara <jack@suse.cz> CC: Dave Chinner <david@fromorbit.com> CC: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
writeback: stop background writeback when below background threshold
Treat bdi_start_writeback(0) as a special request to do background write,
and stop such work when we are below the background dirty threshold.
Also simplify the (nr_pages <= 0) checks. Since we already pass in
nr_pages=LONG_MAX for WB_SYNC_ALL and background writes, we don't
need to worry about it being decreased to zero.
Reported-by: Richard Kennedy <richard@rsk.demon.co.uk> CC: Jan Kara <jack@suse.cz> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
writeback: balance_dirty_pages() shall write more than dirtied pages
Some filesystem may choose to write much more than ratelimit_pages
before calling balance_dirty_pages_ratelimited_nr(). So it is safer to
determine number to write based on real number of dirtied pages.
Otherwise it is possible that
loop {
btrfs_file_write(): dirty 1024 pages
balance_dirty_pages(): write up to 48 pages (= ratelimit_pages * 1.5)
}
in which the writeback rate cannot keep up with dirty rate, and the
dirty pages go all the way beyond dirty_thresh.
The increased write_chunk may make the dirtier more bumpy.
So filesystems shall be take care not to dirty too much at
a time (eg. > 4MB) without checking the ratelimit.
Jan Kara [Wed, 16 Sep 2009 17:22:48 +0000 (19:22 +0200)]
fs: Fix busyloop in wb_writeback()
If all inodes are under writeback (e.g. in case when there's only one inode
with dirty pages), wb_writeback() with WB_SYNC_NONE work basically degrades
to busylooping until I_SYNC flags of the inode is cleared. Fix the problem by
waiting on I_SYNC flags of an inode on b_more_io list in case we failed to
write anything.
Tested-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
IA64 implementation has a couple of differences because of the
available atomic operations ... e.g. we have no fetchadd2 instruction
that operates on a 16-bit quantity so we make ticket locks use
a 32-bit word for each of the current ticket and now-serving values.
Performance on uncontended locks is about 8% worse than the previous
implementation, but this seems a good trade for determinism in the
contended case. Performance impact on macro-level benchmarks is in
the noise.
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6:
sh_mobile_ceu_camera: fix compile breakage, caused by a bad merge
sh: Add support DMA Engine to SH7780
sh: Add support DMA Engine to SH7722
sh: enable onenand support in kfr2r09 defconfig.
sh: update defconfigs.
sh: add FSI driver support for ms7724se
sh: Fix up uninitialized variable use caught by gcc 4.4.
sh: Handle unaligned 16-bit instructions on SH-2A.
sh: mach-ecovec24: Add active low setting for sh_eth
sh: includecheck fix: dwarf.c
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (94 commits)
genetlink: fix netns vs. netlink table locking (2)
3c59x: Get rid of "Trying to free already-free IRQ"
tunnel: eliminate recursion field
ems_pci: fix size of CAN controllers BAR mapping for CPC-PCI v2
net: fix htmldocs sunrpc, clnt.c
Phonet: error on broadcast sending (unimplemented)
Phonet: fix race for port number in concurrent bind()
pktgen: better scheduler friendliness
pktgen: T_TERMINATE flag is unused
ipv4: check optlen for IP_MULTICAST_IF option
ath9k: Initialize txgain and rxgain for newer AR9287 chipsets.
iwlagn: fix panic in iwl{5000,4965}_rx_reply_tx
ath9k: Fix RFKILL bugs
drivers/net/wireless: Use usb_endpoint_dir_out
cfg80211: don't overwrite privacy setting
wl12xx: fix kconfig/link errors
rt2x00: fix the definition of rt2x00crypto_rx_insert_iv
iwlwifi: reduce noise when skb allocation fails
iwlwifi: do not send sync command while holding spinlock
mac80211: fix DTIM setting
...
[WATCHDOG] Add support for the Avionic Design Xanthos watchdog timer.
This patch adds support for the watchdog timer on Avionic Design Xanthos
boards.
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Signed-off-by: Kuninori Morimoto <morimoto.kuninori@renesas.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Merge branch 'for-linus' of git://www.linux-m32r.org/git/takata/linux-2.6_dev
* 'for-linus' of git://www.linux-m32r.org/git/takata/linux-2.6_dev:
m32r: Cleanup linker script using new linker script macros.
m32r: Move the spi_stack_top and spu_stack_top into .init.data section.
m32r: Remove unused .altinstructions and .exit.* code from linker script.
m32r: Move GET_THREAD_INFO definition out of asm/thread_info.h.
m32r: Define THREAD_SIZE only once.
m32r: make PAGE_SIZE available to assembly.
Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
Fix build of cpm_uart due to core changes
powerpc/8xx: Fix regression introduced by cache coherency rewrite
powerpc/4xx: Fix erroneous xmon warning on PowerPC 4xx
powerpc/mm: Fix 40x and 8xx vs. _PAGE_SPECIAL
powerpc: Cleanup linker script using new linker script macros.
powerpc: Fix ibm,client-architecture-support printout
powerpc: Increase NODES_SHIFT on 64bit from 4 to 8
powerpc/perf_counter: Fix vdso detection
powerpc: Move 64bit heap above 1TB on machines with 1TB segments
powerpc: Change archdata dma_data to a union
powerpc: Rename get_dma_direct_offset get_dma_offset
powerpc/mm: Remove duplicated #include
powerpc/book3e-64: Remove duplicated #include
powerpc: Check for unsupported relocs when using CONFIG_RELOCATABLE
powerpc/pmc: Don't access lppaca on Book3E
powerpc: kmalloc failure ignored in vio_build_iommu_table()
hvc_console: Provide (un)locked version for hvc_resize()