Dopey bug. Causes hopelessly-wrong numbers from vmstat(8) and several other
counters.
Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch gets rid of CONFIG_TSI108_BRIDGE. I add UPIO_TSI to
handle IIR and IER register in serial_in and serial_out.
(1) the reason to rewrite serial_in:
TSI108 rev Z1 version ERRATA. Reading the UART's Interrupt
Identification Register (IIR) clears the Transmit Holding Register
Empty (THRE) and Transmit buffer Empty (TEMP) interrupts even if they
are not enabled in the Interrupt Enable Register (IER). This leads to
loss of the interrupts. Interrupts are not cleared when reading UART
registers as 32-bit word.
(2) the reason to rewrite serial_out:
Check for UART_IER_UUE bit in the autoconfig routine. This section
of autoconfig is excluded for Tsi108/109 because bits 7 and 6 are
reserved for internal use. They are R/W bits. In addition to
incorrect identification, changing these bits (from 00) will make
Tsi108/109 UART non-functional.
Signed-off-by: Roy Zang <tie-fei.zang@freescale.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Certain subsystems in the stack (e.g., netfilter) can break the partial
checksum on GSO packets. Until they're fixed, this patch allows this to
work by recomputing the partial checksums through the GSO mechanism.
Once they've all been converted to update the partial checksum instead of
clearing it, this workaround can be removed.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the wrapper function skb_is_gso which can be used instead
of directly testing skb_shinfo(skb)->gso_size. This makes things a little
nicer and allows us to change the primary key for indicating whether an skb
is GSO (if we ever want to do that).
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Provide the needed kernel support for distinguishing readahead
from regular read requests when tracing block devices.
Signed-off-by: Nathan Scott <nathans@sgi.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
Create input_inject_event() function which is to be used by input
handlers as opposed to input_event() which is reserved for drivers
implementing input devices. The difference is that if device is
"grabbed" by some process input_inject_event() will ignore events
unless sent from the handle that is currently owns the device.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
The new start() method is called immediately after connect() and also
when "grabbed" device is released by its owner. This will allow input
handlers to re-synchronize state of once-grabbed device with the rest
of devices.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
This method used to enforce exclusive access to iforce devices,
but presenlty there are no known users of this method.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Reimplement controller-wide PM. ata_host_set_suspend/resume() are
defined to suspend and resume a host_set. While suspended, EHs for
all ports in the host_set are pegged using ATA_FLAG_SUSPENDED and
frozen.
Because SCSI device hotplug is done asynchronously against the rest of
libata EH and the same mutex is used when adding new device, suspend
cannot wait for hotplug to complete. So, if SCSI device hotplug is in
progress, suspend fails with -EBUSY.
In most cases, host_set resume is followed by device resume. As each
resume operation requires a reset, a single host_set-wide resume
operation may result in multiple resets. To avoid this, resume waits
upto 1 second giving PM to request resume for devices.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Reimplement per-dev PM. The original implementation directly put the
device into suspended mode and didn't synchronize w/ EH operations
including hotplug. This patch reimplements ata_scsi_device_suspend()
and ata_scsi_device_resume() such that they request EH to perform the
respective operations. Both functions synchronize with hotplug such
that it doesn't operate on detached devices.
Suspend waits for completion but resume just issues request and
returns. This allows parallel wake up of devices and thus speeds up
system resume.
Due to sdev detach synchronization, it's not feasible to separate out
EH requesting from sdev handling; thus, ata_device_suspend/resume()
are removed and everything is implemented in the respective
libata-scsi functions.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Implement two PM per-dev EH actions - ATA_EH_SUSPEND and
ATA_EH_RESUME. Each action puts the target device into suspended mode
and resumes from it respectively.
Once a device is put to suspended mode, no EH operations other than
RESUME is allowed on the device. The device will stay suspended till
it gets resumed and thus reset and revalidated. To implement this, a
new device state helper - ata_dev_ready() - is implemented and used in
EH action implementations to make them operate only on attached &
running devices.
If all possible devices on a port are suspended, reset is skipped too.
This prevents spurious events including hotplug events from disrupting
suspended devices.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Separate out __ata_ehi_hotplugged() from ata_ehi_hotplugged(). The
underscored version doesn't set AC_ERR_ATA_BUS. This will be used for
resume which is a hotplug event but not an ATA bus error.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Implement ATA_EHI_NO_AUTOPSY and QUIET. These used to be implied by
ATA_PFLAG_LOADING, but new power management and PMP support need to
use these separately. e.g. Suspend/resume operations shouldn't print
full EH messages and resume shouldn't be recorded as an error.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The names of predefined debounce timing parameters didn't exactly
match their usages. Rename to more generic names and implement param
selection helper sata_ehc_deb_timing() which uses EHI_HOTPLUGGED to
select params.
Combined with the previous EHI_RESUME_LINK differentiation, this makes
parameter selection accurate. e.g. user scan resumes link but normal
deb param is used instead of hotplug param.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Implement ATA_EHI_RESUME_LINK, which indicates that the link needs to
be resumed. This used to be implied by ATA_EHI_HOTPLUGGED. However,
hotplug isn't the only event which requires link resume and separating
this out allows other places to request link resume. This
differentiation also allows better debounce timing selection.
This patch converts user scan to use ATA_EHI_RESUME_LINK.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ap->flags is way too clamped. Separate out core dynamic flags to
ap->pflags. ATA_FLAG_DISABLED is a dynamic flag but left alone as
it's referenced by a lot of LLDs and it's gonna be removed once all
LLDs are converted to new EH.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Change posix_lock_file_conf(), and flock_lock_file() so that if called
with an F_UNLCK argument, and the FL_EXISTS flag they will indicate
whether or not any locks were actually freed by returning 0 or -ENOENT.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
* master.kernel.org:/pub/scm/linux/kernel/git/davej/cpufreq:
Move workqueue exports to where the functions are defined.
[CPUFREQ] Misc cleanups in ondemand.
[CPUFREQ] Make ondemand sampling per CPU and remove the mutex usage in sampling path.
[CPUFREQ] Add queue_delayed_work_on() interface for workqueues.
[CPUFREQ] Remove slowdown from ondemand sampling path.
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-serial:
[SERIAL] Ensure 8250_pci quirks are not marked __devinit
[SERIAL] Convert fifosize to an unsigned int
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6: (27 commits)
[Bluetooth] Add RFCOMM role switch support
[Bluetooth] Allow disabling of credit based flow control
[Bluetooth] Small cleanup of the L2CAP source code
[Bluetooth] Use real devices for host controllers
[Bluetooth] Add platform device for virtual and serial devices
[Bluetooth] Add automatic sniff mode support
[Bluetooth] Correct SCO buffer size on request
[Bluetooth] Add suspend/resume support to the HCI USB driver
[Bluetooth] Use raw mode for the Frontline sniffer device
[BRIDGE]: br_dump_ifinfo index fix
[ATM]: add+use poison defines
[NET]: add+use poison defines
[IOAT]: fix kernel-doc in source files
[IOAT]: fix header file kernel-doc
[TG3]: Add ipv6 TSO feature
[IPV6]: Fix ipv6 GSO payload length
[TIPC] Fixed sk_buff panic caused by tipc_link_bundle_buf (REVISED)
[NET]: Verify gso_type too in gso_segment
[IPVS]: Add sysctl documentation
[ROSE]: Try all routes when establishing a ROSE connections.
...
Fix kernel-doc problems in include/linux/dmaengine.h:
- add some fields/parameters
- expand some descriptions
- fix typos
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
convert:
- runqueue_t to 'struct rq'
- prio_array_t to 'struct prio_array'
- migration_req_t to 'struct migration_req'
I was the one who added these but they are both against the kernel coding
style and also were used inconsistently at places. So just get rid of them at
once, now that we are flushing the scheduler patch-queue anyway.
Conversion was mostly scripted, the result was reviewed and all secondary
whitespace and style impact (if any) was fixed up by hand.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
cleanup: remove task_t and convert all the uses to struct task_struct. I
introduced it for the scheduler anno and it was a mistake.
Conversion was mostly scripted, the result was reviewed and all
secondary whitespace and style impact (if any) was fixed up by hand.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator.
Effects on non-lockdep kernels:
- the introduction of the following function variants:
extern struct block_device *open_partition_by_devnum(dev_t, unsigned);
extern int blkdev_put_partition(struct block_device *);
static int
blkdev_get_whole(struct block_device *bdev, mode_t mode, unsigned flags);
which on non-lockdep are the same as open_by_devnum(), blkdev_put()
and blkdev_get().
- a subclass parameter to do_open(). [unused on non-lockdep]
- a subclass parameter to __blkdev_put(), which is a new internal
function for the main blkdev_put*() functions. [parameter unused
on non-lockdep kernels, except for two sanity check WARN_ON()s]
these functions carry no semantical difference - they only express
object dependencies towards the lockdep subsystem.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The s_umount rwsem needs to be classified as per-superblock since it's
perfectly legit to keep multiple of those recursively in the VFS locking
rules.
Has no effect on non-lockdep kernels.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (per-filesystem) locking code to the lock validator.
Minimal effect on non-lockdep kernels: one extra parameter to alloc_super().
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make use of local_irq_enable_in_hardirq() API to annotate places that enable
hardirqs in hardirq context.
Has no effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Has no effect
on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (multi-initialized) locking code to the lock validator. Has no
effect on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Create one lock class for all waitqueue locks in the kernel. Has no effect on
non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Has no effect
on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Has no effect
on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Teach special (recursive) locking code to the lock validator. Has no effect
on non-lockdep kernels.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the lock validator framework to prove mutex locking correctness.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the lock validator framework to prove spinlock and rwlock locking
correctness.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use the lock validator framework to prove rwsem locking correctness.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Do 'make oldconfig' and accept all the defaults for new config options -
reboot into the kernel and if everything goes well it should boot up fine and
you should have /proc/lockdep and /proc/lockdep_stats files.
Typically if the lock validator finds some problem it will print out
voluminous debug output that begins with "BUG: ..." and which syslog output
can be used by kernel developers to figure out the precise locking scenario.
What does the lock validator do? It "observes" and maps all locking rules as
they occur dynamically (as triggered by the kernel's natural use of spinlocks,
rwlocks, mutexes and rwsems). Whenever the lock validator subsystem detects a
new locking scenario, it validates this new rule against the existing set of
rules. If this new rule is consistent with the existing set of rules then the
new rule is added transparently and the kernel continues as normal. If the
new rule could create a deadlock scenario then this condition is printed out.
When determining validity of locking, all possible "deadlock scenarios" are
considered: assuming arbitrary number of CPUs, arbitrary irq context and task
context constellations, running arbitrary combinations of all the existing
locking scenarios. In a typical system this means millions of separate
scenarios. This is why we call it a "locking correctness" validator - for all
rules that are observed the lock validator proves it with mathematical
certainty that a deadlock could not occur (assuming that the lock validator
implementation itself is correct and its internal data structures are not
corrupted by some other kernel subsystem). [see more details and conditionals
of this statement in include/linux/lockdep.h and
Documentation/lockdep-design.txt]
Furthermore, this "all possible scenarios" property of the validator also
enables the finding of complex, highly unlikely multi-CPU multi-context races
via single single-context rules, increasing the likelyhood of finding bugs
drastically. In practical terms: the lock validator already found a bug in
the upstream kernel that could only occur on systems with 3 or more CPUs, and
which needed 3 very unlikely code sequences to occur at once on the 3 CPUs.
That bug was found and reported on a single-CPU system (!). So in essence a
race will be found "piecemail-wise", triggering all the necessary components
for the race, without having to reproduce the race scenario itself! In its
short existence the lock validator found and reported many bugs before they
actually caused a real deadlock.
To further increase the efficiency of the validator, the mapping is not per
"lock instance", but per "lock-class". For example, all struct inode objects
in the kernel have inode->inotify_mutex. If there are 10,000 inodes cached,
then there are 10,000 lock objects. But ->inotify_mutex is a single "lock
type", and all locking activities that occur against ->inotify_mutex are
"unified" into this single lock-class. The advantage of the lock-class
approach is that all historical ->inotify_mutex uses are mapped into a single
(and as narrow as possible) set of locking rules - regardless of how many
different tasks or inode structures it took to build this set of rules. The
set of rules persist during the lifetime of the kernel.
To see the rough magnitude of checking that the lock validator does, here's a
portion of /proc/lockdep_stats, fresh after bootup:
lock-classes: 694 [max: 2048]
direct dependencies: 1598 [max: 8192]
indirect dependencies: 17896
all direct dependencies: 16206
dependency chains: 1910 [max: 8192]
in-hardirq chains: 17
in-softirq chains: 105
in-process chains: 1065
stack-trace entries: 38761 [max: 131072]
combined max dependencies: 2033928
hardirq-safe locks: 24
hardirq-unsafe locks: 176
softirq-safe locks: 53
softirq-unsafe locks: 137
irq-safe locks: 59
irq-unsafe locks: 176
The lock validator has observed 1598 actual single-thread locking patterns,
and has validated all possible 2033928 distinct locking scenarios.
More details about the design of the lock validator can be found in
Documentation/lockdep-design.txt, which can also found at:
http://redhat.com/~mingo/lockdep-patches/lockdep-design.txt
[bunk@stusta.de: cleanups]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Accurate hard-IRQ-flags and softirq-flags state tracing.
This allows us to attach extra functionality to IRQ flags on/off
events (such as trace-on/off).
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
