Commit Graph

256873 Commits

Author SHA1 Message Date
Paul E. McKenney
a841796f11 signal: align __lock_task_sighand() irq disabling and RCU
The __lock_task_sighand() function calls rcu_read_lock() with interrupts
and preemption enabled, but later calls rcu_read_unlock() with interrupts
disabled.  It is therefore possible that this RCU read-side critical
section will be preempted and later RCU priority boosted, which means that
rcu_read_unlock() will call rt_mutex_unlock() in order to deboost itself, but
with interrupts disabled. This results in lockdep splats, so this commit
nests the RCU read-side critical section within the interrupt-disabled
region of code.  This prevents the RCU read-side critical section from
being preempted, and thus prevents the attempt to deboost with interrupts
disabled.

It is quite possible that a better long-term fix is to make rt_mutex_unlock()
disable irqs when acquiring the rt_mutex structure's ->wait_lock.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-07-20 11:04:54 -07:00
Peter Zijlstra
ec433f0c51 softirq,rcu: Inform RCU of irq_exit() activity
The rcu_read_unlock_special() function relies on in_irq() to exclude
scheduler activity from interrupt level.  This fails because exit_irq()
can invoke the scheduler after clearing the preempt_count() bits that
in_irq() uses to determine that it is at interrupt level.  This situation
can result in failures as follows:

 $task			IRQ		SoftIRQ

 rcu_read_lock()

 /* do stuff */

 <preempt> |= UNLOCK_BLOCKED

 rcu_read_unlock()
   --t->rcu_read_lock_nesting

			irq_enter();
			/* do stuff, don't use RCU */
			irq_exit();
			  sub_preempt_count(IRQ_EXIT_OFFSET);
			  invoke_softirq()

					ttwu();
					  spin_lock_irq(&pi->lock)
					  rcu_read_lock();
					  /* do stuff */
					  rcu_read_unlock();
					    rcu_read_unlock_special()
					      rcu_report_exp_rnp()
					        ttwu()
					          spin_lock_irq(&pi->lock) /* deadlock */

   rcu_read_unlock_special(t);

Ed can simply trigger this 'easy' because invoke_softirq() immediately
does a ttwu() of ksoftirqd/# instead of doing the in-place softirq stuff
first, but even without that the above happens.

Cure this by also excluding softirqs from the
rcu_read_unlock_special() handler and ensuring the force_irqthreads
ksoftirqd/# wakeup is done from full softirq context.

[ Alternatively, delaying the ->rcu_read_lock_nesting decrement
  until after the special handling would make the thing more robust
  in the face of interrupts as well.  And there is a separate patch
  for that. ]

Cc: Thomas Gleixner <tglx@linutronix.de>
Reported-and-tested-by: Ed Tomlinson <edt@aei.ca>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-07-20 10:50:12 -07:00
Peter Zijlstra
c5d753a55a sched: Add irq_{enter,exit}() to scheduler_ipi()
Ensure scheduler_ipi() calls irq_{enter,exit} when it does some actual
work. Traditionally we never did any actual work from the resched IPI
and all magic happened in the return from interrupt path.

Now that we do do some work, we need to ensure irq_{enter,exit} are
called so that we don't confuse things.

This affects things like timekeeping, NO_HZ and RCU, basically
everything with a hook in irq_enter/exit.

Explicit examples of things going wrong are:

  sched_clock_cpu() -- has a callback when leaving NO_HZ state to take
                    a new reading from GTOD and TSC. Without this
                    callback, time is stuck in the past.

  RCU -- needs in_irq() to work in order to avoid some nasty deadlocks

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-07-20 10:50:11 -07:00
Paul E. McKenney
10f39bb1b2 rcu: protect __rcu_read_unlock() against scheduler-using irq handlers
The addition of RCU read-side critical sections within runqueue and
priority-inheritance lock critical sections introduced some deadlock
cycles, for example, involving interrupts from __rcu_read_unlock()
where the interrupt handlers call wake_up().  This situation can cause
the instance of __rcu_read_unlock() invoked from interrupt to do some
of the processing that would otherwise have been carried out by the
task-level instance of __rcu_read_unlock().  When the interrupt-level
instance of __rcu_read_unlock() is called with a scheduler lock held
from interrupt-entry/exit situations where in_irq() returns false,
deadlock can result.

This commit resolves these deadlocks by using negative values of
the per-task ->rcu_read_lock_nesting counter to indicate that an
instance of __rcu_read_unlock() is in flight, which in turn prevents
instances from interrupt handlers from doing any special processing.
This patch is inspired by Steven Rostedt's earlier patch that similarly
made __rcu_read_unlock() guard against interrupt-mediated recursion
(see https://lkml.org/lkml/2011/7/15/326), but this commit refines
Steven's approach to avoid the need for preemption disabling on the
__rcu_read_unlock() fastpath and to also avoid the need for manipulating
a separate per-CPU variable.

This patch avoids need for preempt_disable() by instead using negative
values of the per-task ->rcu_read_lock_nesting counter.  Note that nested
rcu_read_lock()/rcu_read_unlock() pairs are still permitted, but they will
never see ->rcu_read_lock_nesting go to zero, and will therefore never
invoke rcu_read_unlock_special(), thus preventing them from seeing the
RCU_READ_UNLOCK_BLOCKED bit should it be set in ->rcu_read_unlock_special.
This patch also adds a check for ->rcu_read_unlock_special being negative
in rcu_check_callbacks(), thus preventing the RCU_READ_UNLOCK_NEED_QS
bit from being set should a scheduling-clock interrupt occur while
__rcu_read_unlock() is exiting from an outermost RCU read-side critical
section.

Of course, __rcu_read_unlock() can be preempted during the time that
->rcu_read_lock_nesting is negative.  This could result in the setting
of the RCU_READ_UNLOCK_BLOCKED bit after __rcu_read_unlock() checks it,
and would also result it this task being queued on the corresponding
rcu_node structure's blkd_tasks list.  Therefore, some later RCU read-side
critical section would enter rcu_read_unlock_special() to clean up --
which could result in deadlock if that critical section happened to be in
the scheduler where the runqueue or priority-inheritance locks were held.

This situation is dealt with by making rcu_preempt_note_context_switch()
check for negative ->rcu_read_lock_nesting, thus refraining from
queuing the task (and from setting RCU_READ_UNLOCK_BLOCKED) if we are
already exiting from the outermost RCU read-side critical section (in
other words, we really are no longer actually in that RCU read-side
critical section).  In addition, rcu_preempt_note_context_switch()
invokes rcu_read_unlock_special() to carry out the cleanup in this case,
which clears out the ->rcu_read_unlock_special bits and dequeues the task
(if necessary), in turn avoiding needless delay of the current RCU grace
period and needless RCU priority boosting.

It is still illegal to call rcu_read_unlock() while holding a scheduler
lock if the prior RCU read-side critical section has ever had either
preemption or irqs enabled.  However, the common use case is legal,
namely where then entire RCU read-side critical section executes with
irqs disabled, for example, when the scheduler lock is held across the
entire lifetime of the RCU read-side critical section.

Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-07-20 10:50:11 -07:00
Eric Dumazet
b56efcf0a4 slab: shrink sizeof(struct kmem_cache)
Reduce high order allocations for some setups.
(NR_CPUS=4096 -> we need 64KB per kmem_cache struct)

We now allocate exact needed size (using nr_cpu_ids and nr_node_ids)

This also makes code a bit smaller on x86_64, since some field offsets
are less than the 127 limit :

Before patch :
# size mm/slab.o
   text    data     bss     dec     hex filename
  22605  361665      32  384302   5dd2e mm/slab.o

After patch :
# size mm/slab.o
   text    data     bss     dec     hex filename
  22349	 353473	   8224	 384046	  5dc2e	mm/slab.o

CC: Andrew Morton <akpm@linux-foundation.org>
Reported-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
2011-07-20 20:27:56 +03:00
Peter Zijlstra
d110235d2c sched: Avoid creating superfluous NUMA domains on non-NUMA systems
When creating sched_domains, stop when we've covered the entire
target span instead of continuing to create domains, only to
later find they're redundant and throw them away again.

This avoids single node systems from touching funny NUMA
sched_domain creation code and reduces the risks of the new
SD_OVERLAP code.

Requested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Anton Blanchard <anton@samba.org>
Cc: mahesh@linux.vnet.ibm.com
Cc: benh@kernel.crashing.org
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1311180177.29152.57.camel@twins
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-20 18:54:33 +02:00
Peter Zijlstra
e3589f6c81 sched: Allow for overlapping sched_domain spans
Allow for sched_domain spans that overlap by giving such domains their
own sched_group list instead of sharing the sched_groups amongst
each-other.

This is needed for machines with more than 16 nodes, because
sched_domain_node_span() will generate a node mask from the
16 nearest nodes without regard if these masks have any overlap.

Currently sched_domains have a sched_group that maps to their child
sched_domain span, and since there is no overlap we share the
sched_group between the sched_domains of the various CPUs. If however
there is overlap, we would need to link the sched_group list in
different ways for each cpu, and hence sharing isn't possible.

In order to solve this, allocate private sched_groups for each CPU's
sched_domain but have the sched_groups share a sched_group_power
structure such that we can uniquely track the power.

Reported-and-tested-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-08bxqw9wis3qti9u5inifh3y@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-20 18:32:41 +02:00
Peter Zijlstra
9c3f75cbd1 sched: Break out cpu_power from the sched_group structure
In order to prepare for non-unique sched_groups per domain, we need to
carry the cpu_power elsewhere, so put a level of indirection in.

Reported-and-tested-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/n/tip-qkho2byuhe4482fuknss40ad@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-07-20 18:32:40 +02:00
Axel Lin
2dcd9543a2 HID: emsff: properly handle emsff_init failure
emsff_init() may fail, let's properly handle the failure.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-07-20 11:55:18 +02:00
Linus Torvalds
e6625fa48e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  ceph: fix file mode calculation
2011-07-19 22:10:28 -07:00
Linus Torvalds
47126d807a Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/linux-arm-soc:
  davinci: DM365 EVM: fix video input mux bits
  ARM: davinci: Check for NULL return from irq_alloc_generic_chip
  arm: davinci: Fix low level gpio irq handlers' argument
2011-07-19 22:10:05 -07:00
Shaohua Li
4746efded8 vmscan: fix a livelock in kswapd
I'm running a workload which triggers a lot of swap in a machine with 4
nodes.  After I kill the workload, I found a kswapd livelock.  Sometimes
kswapd3 or kswapd2 are keeping running and I can't access filesystem,
but most memory is free.

This looks like a regression since commit 08951e5459 ("mm: vmscan:
correct check for kswapd sleeping in sleeping_prematurely").

Node 2 and 3 have only ZONE_NORMAL, but balance_pgdat() will return 0
for classzone_idx.  The reason is end_zone in balance_pgdat() is 0 by
default, if all zones have watermark ok, end_zone will keep 0.

Later sleeping_prematurely() always returns true.  Because this is an
order 3 wakeup, and if classzone_idx is 0, both balanced_pages and
present_pages in pgdat_balanced() are 0.  We add a special case here.
If a zone has no page, we think it's balanced.  This fixes the livelock.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Minchan Kim <minchan.kim@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-19 22:09:31 -07:00
Akinobu Mita
f7b88631a8 fs/libfs.c: fix simple_attr_write() on 32bit machines
Assume that /sys/kernel/debug/dummy64 is debugfs file created by
debugfs_create_x64().

	# cd /sys/kernel/debug
	# echo 0x1234567812345678 > dummy64
	# cat dummy64
	0x0000000012345678

	# echo 0x80000000 > dummy64
	# cat dummy64
	0xffffffff80000000

A value larger than INT_MAX cannot be written to the debugfs file created
by debugfs_create_u64 or debugfs_create_x64 on 32bit machine.  Because
simple_attr_write() uses simple_strtol() for the conversion.

To fix this, use simple_strtoll() instead.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-19 22:09:30 -07:00
Linus Torvalds
e501f29c72 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:
  vfs: fix race in rcu lookup of pruned dentry
  Fix cifs_get_root()

[ Edited the last commit to get rid of a 'unused variable "seq"'
  warning due to Al editing the patch.  - Linus ]
2011-07-19 21:50:21 -07:00
Linus Torvalds
5943026240 vfs: fix race in rcu lookup of pruned dentry
Don't update *inode in __follow_mount_rcu() until we'd verified that
there is mountpoint there.  Kudos to Hugh Dickins for catching that
one in the first place and eventually figuring out the solution (and
catching a braino in the earlier version of patch).

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-19 21:49:01 -07:00
Paul E. McKenney
be0e1e21ef rcu: Streamline code produced by __rcu_read_unlock()
Given some common flag combinations, particularly -Os, gcc will inline
rcu_read_unlock_special() despite its being in an unlikely() clause.
Use noinline to prohibit this misoptimization.

In addition, move the second barrier() in __rcu_read_unlock() so that
it is not on the common-case code path.  This will allow the compiler to
generate better code for the common-case path through __rcu_read_unlock().

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
2011-07-19 21:38:53 -07:00
Paul E. McKenney
7765be2fec rcu: Fix RCU_BOOST race handling current->rcu_read_unlock_special
The RCU_BOOST commits for TREE_PREEMPT_RCU introduced an other-task
write to a new RCU_READ_UNLOCK_BOOSTED bit in the task_struct structure's
->rcu_read_unlock_special field, but, as noted by Steven Rostedt, without
correctly synchronizing all accesses to ->rcu_read_unlock_special.
This could result in bits in ->rcu_read_unlock_special being spuriously
set and cleared due to conflicting accesses, which in turn could result
in deadlocks between the rcu_node structure's ->lock and the scheduler's
rq and pi locks.  These deadlocks would result from RCU incorrectly
believing that the just-ended RCU read-side critical section had been
preempted and/or boosted.  If that RCU read-side critical section was
executed with either rq or pi locks held, RCU's ensuing (incorrect)
calls to the scheduler would cause the scheduler to attempt to once
again acquire the rq and pi locks, resulting in deadlock.  More complex
deadlock cycles are also possible, involving multiple rq and pi locks
as well as locks from multiple rcu_node structures.

This commit fixes synchronization by creating ->rcu_boosted field in
task_struct that is accessed and modified only when holding the ->lock
in the rcu_node structure on which the task is queued (on that rcu_node
structure's ->blkd_tasks list).  This results in tasks accessing only
their own current->rcu_read_unlock_special fields, making unsynchronized
access once again legal, and keeping the rcu_read_unlock() fastpath free
of atomic instructions and memory barriers.

The reason that the rcu_read_unlock() fastpath does not need to access
the new current->rcu_boosted field is that this new field cannot
be non-zero unless the RCU_READ_UNLOCK_BLOCKED bit is set in the
current->rcu_read_unlock_special field.  Therefore, rcu_read_unlock()
need only test current->rcu_read_unlock_special: if that is zero, then
current->rcu_boosted must also be zero.

This bug does not affect TINY_PREEMPT_RCU because this implementation
of RCU accesses current->rcu_read_unlock_special with irqs disabled,
thus preventing races on the !SMP systems that TINY_PREEMPT_RCU runs on.

Maybe-reported-by: Dave Jones <davej@redhat.com>
Maybe-reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
2011-07-19 21:38:52 -07:00
Paul E. McKenney
131906b006 rcu: decrease rcu_report_exp_rnp coupling with scheduler
PREEMPT_RCU read-side critical sections blocking an expedited grace
period invoke rcu_report_exp_rnp().  When the last such critical section
has completed, rcu_report_exp_rnp() invokes the scheduler to wake up the
task that invoked synchronize_rcu_expedited() -- needlessly holding the
root rcu_node structure's lock while doing so, thus needlessly providing
a way for RCU and the scheduler to deadlock.

This commit therefore releases the root rcu_node structure's lock before
calling wake_up().

Reported-by: Ed Tomlinson <edt@aei.ca>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2011-07-19 21:38:51 -07:00
Konrad Rzeszutek Wilk
2ebdc42630 xen/pciback: Have 'passthrough' option instead of XEN_PCIDEV_BACKEND_PASS and XEN_PCIDEV_BACKEND_VPCI
.. compile options. This way the user can decide during runtime whether they
want the default 'vpci' (virtual pci passthrough) or where the PCI devices
are passed in without any BDF renumbering. The option 'passthrough' allows
the user to toggle the it from 0 (vpci) to 1 (passthrough).

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-19 21:04:20 -04:00
Konrad Rzeszutek Wilk
778999703d xen/pciback: Remove the DEBUG option.
The latter is easily fixed - by the developer compiling the
module with -DDEBUG. And during runtime - the loglvl provides
quite a lot of useful data.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-19 21:03:35 -04:00
Konrad Rzeszutek Wilk
a92336a117 xen/pciback: Drop two backends, squash and cleanup some code.
- Remove the slot and controller controller backend as they
   are not used.
 - Document the find pciback_[read|write]_config_[byte|word|dword]
   to make it easier to find.
 - Collapse the code from conf_space_capability_msi into pciback_ops.c
 - Collapse conf_space_capability_[pm|vpd].c in conf_space_capability.c
   [and remove the conf_space_capability.h file]
 - Rename all visible functions from pciback to xen_pcibk.
 - Rename all the printk/pr_info, etc that use the "pciback" to say
   "xen-pciback".
 - Convert functions that are not referenced outside the code to be
   static to save on name space.
 - Do the same thing for structures that are internal to the driver.
 - Run checkpatch.pl after the renames and fixup its warnings and
   fix any compile errors caused by the variable rename
 - Cleanup any structs that checkpath.pl commented about or just
   look odd.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-19 20:58:35 -04:00
Konrad Rzeszutek Wilk
c288b67b9b xen/pciback: Print out the MSI/MSI-X (PIRQ) values
If the verbose_request is set (and loglevel high enough), print out
the MSI/MSI-X values that are sent to the guest. This should aid in
debugging issues.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-19 20:58:34 -04:00
Konrad Rzeszutek Wilk
e17ab35f05 xen/pciback: Don't setup an fake IRQ handler for SR-IOV devices.
If we try to setup an fake IRQ handler for legacy interrupts
for devices that only have MSI-X (most if not all SR-IOV cards),
we will fail with this:

pciback[0000:01:10.0]: failed to install fake IRQ handler for IRQ 0! (rc:-38)

Since those cards don't have anything in dev->irq.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-19 20:58:34 -04:00
Ian Campbell
a0b2fa8ef8 xen: rename pciback module to xen-pciback.
pciback is rather generic for a modular distro style kernel.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-19 20:58:33 -04:00
Konrad Rzeszutek Wilk
494ef20db6 xen/pciback: Fine-grain the spinlocks and fix BUG: scheduling while atomic cases.
We were using coarse spinlocks that could end up with a deadlock.
This patch fixes that and makes the spinlocks much more fine-grained.

We also drop be->watchding state spinlocks as they are already
guarded by the xenwatch_thread against multiple customers. Without
that we would trigger the BUG: scheduling while atomic.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-19 20:58:32 -04:00
Konrad Rzeszutek Wilk
0513fe9e5b xen/pciback: Allocate IRQ handler for device that is shared with guest.
If the device that is to be shared with a guest is a level device and
the IRQ is shared with the initial domain we need to take actions.
Mainly we install a dummy IRQ handler that will ACK on the interrupt
line so as to not have the initial domain disable the interrupt line.

This dummy IRQ handler is not enabled when the device MSI/MSI-X lines
are set, nor for edge interrupts. And also not for level interrupts
that are not shared amongst devices. Lastly, if the user passes
to the guest all of the PCI devices on the shared line the we won't
install the dummy handler either.

There is also SysFS instrumentation to check its state and turn
IRQ ACKing on/off if necessary.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-19 20:58:31 -04:00
Konrad Rzeszutek Wilk
a2be65fd36 xen/pciback: Disable MSI/MSI-X when reseting a device
In cases where the guest is abruptly killed and has not disabled
MSI/MSI-X interrupts we want to do it for it.

Otherwise when the guest is started up and enables MSI, we would
get a WARN() that the device already had been enabled.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-19 20:58:31 -04:00
Zhao, Yu
fd5b221b34 xen/pciback: guest SR-IOV support for PV guest
These changes are for PV guest to use Virtual Function. Because the VF's
vendor, device registers in cfg space are 0xffff, which are invalid and
ignored by PCI device scan. Values in 'struct pci_dev' are fixed up by
SR-IOV code, and using these values will present correct VID and DID to
PV guest kernel.

And command registers in the cfg space are read only 0, which means we
have to emulate MMIO enable bit (VF only uses MMIO  resource) so PV
kernel can work properly.

Acked-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-19 20:58:30 -04:00
Konrad Rzeszutek Wilk
6221a9b2a1 xen/pciback: Register the owner (domain) of the PCI device.
When the front-end and back-end start negotiating we register
the domain that will use the PCI device. Furthermore during shutdown
of guest or unbinding of the PCI device (and unloading of module)
from pciback we unregister the domain owner.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-19 20:58:29 -04:00
Konrad Rzeszutek Wilk
8bfd4e023f xen/pciback: Cleanup the driver based on checkpatch warnings and errors.
Checkpatch found some extra warnings and errors. This mega
patch fixes them all in one big swoop. We also spruce
up the pcistub_ids to use DEFINE_PCI_DEVICE_TABLE macro
(suggested by Jan Beulich).

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-07-19 20:58:28 -04:00
Konrad Rzeszutek Wilk
30edc14bf3 xen/pciback: xen pci backend driver.
This is the host side counterpart to the frontend driver in
drivers/pci/xen-pcifront.c. The PV protocol is also implemented by
frontend drivers in other OSes too, such as the BSDs.

The PV protocol is rather simple. There is page shared with the guest,
which has the 'struct xen_pci_sharedinfo' embossed in it. The backend
has a thread that is kicked every-time the structure is changed and
based on the operation field it performs specific tasks:

 XEN_PCI_OP_conf_[read|write]:
   Read/Write 0xCF8/0xCFC filtered data. (conf_space*.c)
   Based on which field is probed, we either enable/disable the PCI
   device, change power state, read VPD, etc. The major goal of this
   call is to provide a Physical IRQ (PIRQ) to the guest.

   The PIRQ is Xen hypervisor global IRQ value irrespective of the IRQ
   is tied in to the IO-APIC, or is a vector. For GSI type
   interrupts, the PIRQ==GSI holds. For MSI/MSI-X the
   PIRQ value != Linux IRQ number (thought PIRQ==vector).

   Please note, that with Xen, all interrupts (except those level shared ones)
   are injected directly to the guest - there is no host interaction.

 XEN_PCI_OP_[enable|disable]_msi[|x] (pciback_ops.c)
   Enables/disables the MSI/MSI-X capability of the device. These operations
   setup the MSI/MSI-X vectors for the guest and pass them to the frontend.

   When the device is activated, the interrupts are directly injected in the
   guest without involving the host.

 XEN_PCI_OP_aer_[detected|resume|mmio|slotreset]: In case of failure,
  perform the appropriate AER commands on the guest. Right now that is
  a cop-out - we just kill the guest.

Besides implementing those commands, it can also

 - hide a PCI device from the host. When booting up, the user can specify
   xen-pciback.hide=(1:0:0)(BDF..) so that host does not try to use the
   device.

The driver was lifted from linux-2.6.18.hg tree and fixed up
so that it could compile under v3.0. Per suggestion from Jesse Barnes
moved the driver to drivers/xen/xen-pciback.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2011-07-19 20:58:01 -04:00
Matvejchikov Ilya
7ad711b49e slcan: remove unused 'leased', 'line' and 'pid' fields from the 'slcan' structure
Signed-off-by: Matvejchikov Ilya <matvejchikov@gmail.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-19 16:55:42 -07:00
Matvejchikov Ilya
a9481a38b1 slip: remove unused 'line' field from the 'slip' structure
Signed-off-by: Matvejchikov Ilya <matvejchikov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-19 16:55:42 -07:00
David Teigland
10d1459faf dlm: don't limit active work items
Allow multiple workqueue items (locks with callbacks) to be
processed concurrently.  There should be no reason not to
take advantage of this workqueue feature.

Signed-off-by: David Teigland <teigland@redhat.com>
2011-07-19 14:22:32 -05:00
Shawn Guo
591567a5ea gpio/mxc/mxs: fix build error introduced by the irq_gc_ack() renaming
The following commit renames irq_gc_ack() to irq_gc_ack_set_bit(),
and makes gpio-mxc and gpio-mxs fail to build.

  659fb32d1b
  genirq: replace irq_gc_ack() with {set,clr}_bit variants (fwd)

The patch fixed a couple of typo of comma to semicolon.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-07-19 13:10:02 -06:00
Sage Weil
38be7a79f7 ceph: fix file mode calculation
open(2) must always include one of O_RDONLY, O_WRONLY, or O_RDWR.  No need
for any O_APPEND special case.

Passing O_WRONLY|O_RDWR is undefined according to the man page, but the
Linux VFS interprets this as O_RDWR, so we'll do the same.

This fixes open(2) with flags O_RDWR|O_APPEND, which was incorrectly being
translated to readonly.

Reported-by: Fyodor Ustinov <ufm@ufm.su>
Signed-off-by: Sage Weil <sage@newdream.net>
2011-07-19 11:25:04 -07:00
David S. Miller
fd99beb937 Merge branch 'vhost-net-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost 2011-07-19 10:12:44 -07:00
David S. Miller
3fbcf6bb55 Merge branch 'davem-next.r8169' of git://git.kernel.org/pub/scm/linux/kernel/git/romieu/netdev-2.6 2011-07-19 10:11:21 -07:00
Dmitry Kravkov
928ad22a3b bnx2x: disable FCoE for 578xx devices since not yet supported
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-19 09:57:49 -07:00
Vladislav Zolotarov
53e51e2f48 bnx2x: fix memory barriers
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-19 09:57:49 -07:00
Vladislav Zolotarov
f5219d8eb8 bnx2x: use BNX2X_Q_FLG_TPA_IPV6 for TPA queue configuration
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-19 09:57:49 -07:00
Vladislav Zolotarov
019dbb4c01 bnx2x: disable loacal BH when scheduling FCOE napi
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-19 09:57:49 -07:00
Dmitry Kravkov
d1c228d9b9 bnx2x: fix MB index for 4-port devices
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-19 09:57:49 -07:00
Dmitry Kravkov
6debea870a bnx2x: DCB rework
create DCB related states in function state-machine
allow handling of DCB errors from FW
allow disablement of DCB in FW, when peer disappears or error
clean up unused functions/variables as pointed by
David Binderman <dcb314@hotmail.com>

Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-19 09:57:48 -07:00
Vladislav Zolotarov
f13ac41f51 bnx2x: remove unnecessary dma_sync
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-19 09:57:48 -07:00
Vladislav Zolotarov
9505ee3767 bnx2x: stop tx before CNIC_STOP
It may take some time to cnic to respond, this prevents tx_timeout
when it happens.

Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-19 09:57:48 -07:00
Dmitry Kravkov
c636322b24 bnx2x: add missing command in error handling flow
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-19 09:57:47 -07:00
Vladislav Zolotarov
9924cafc40 bnx2x: use correct dma_sync function
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-07-19 09:57:46 -07:00
Francois Romieu
1687b56679 r8169: fix sticky accepts packet bits in RxConfig.
e542a2269f (r8169: adjust the RxConfig settings)
broke the return from promiscuous mode to physical address match mode.

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Cc: Signed-off-by: Hayes Wang <hayeswang@realtek.com>
2011-07-19 17:28:03 +02:00
Michael S. Tsirkin
b834226b04 vhost: optimize interrupt enable/disable
As we now only update used ring after enabling
the backend, we can write flags with __put_user:
as that's done on data path, it matters.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2011-07-19 17:17:28 +03:00