20 May, 2015
1 commit
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A non-percpu VIRQ (e.g., VIRQ_CONSOLE) may be freed on a different
VCPU than it is bound to. This can result in a race between
handle_percpu_irq() and removing the action in __free_irq() because
handle_percpu_irq() does not take desc->lock. The interrupt handler
sees a NULL action and oopses.Only use the percpu chip/handler for per-CPU VIRQs (like VIRQ_TIMER).
# cat /proc/interrupts | grep virq
40: 87246 0 xen-percpu-virq timer0
44: 0 0 xen-percpu-virq debug0
47: 0 20995 xen-percpu-virq timer1
51: 0 0 xen-percpu-virq debug1
69: 0 0 xen-dyn-virq xen-pcpu
74: 0 0 xen-dyn-virq mce
75: 29 0 xen-dyn-virq hvc_consoleSigned-off-by: David Vrabel
Cc:
23 Sep, 2014
1 commit
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Export bind_interdomain_evtchn_to_irq() so drivers can use threaded
interrupt handlers with:irq = bind_interdomain_evtchn_to_irq(remote_dom, remote_port);
if (irq < 0)
/* error */
ret = request_threaded_irq(...);Signed-off-by: Juergen Gross
Acked-by: Konrad Rzeszutek Wilk
Signed-off-by: David Vrabel
18 Mar, 2014
1 commit
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Add support for MSI message groups for Xen Dom0 using the
MAP_PIRQ_TYPE_MULTI_MSI pirq map type.In order to keep track of which pirq is the first one in the group all
pirqs in the MSI group except for the first one have the newly
introduced PIRQ_MSI_GROUP flag set. This prevents calling
PHYSDEVOP_unmap_pirq on them, since the unmap must be done with the
first pirq in the group.Signed-off-by: Roger Pau Monné
Signed-off-by: David Vrabel
Cc: Boris Ostrovsky
01 Mar, 2014
1 commit
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resend_irq_on_evtchn() was only used by ia64 (which no longer has Xen
support).Signed-off-by: David Vrabel
Signed-off-by: Konrad Rzeszutek Wilk
Reviewed-by: Boris Ostrovsky
06 Jan, 2014
3 commits
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Add xen_irq_set_priority() to set an event channels priority. This function
will only work with event channel ABIs that support priority (i.e., the
FIFO-based ABI).Signed-off-by: David Vrabel
Reviewed-by: Konrad Rzeszutek Wilk
Reviewed-by: Boris Ostrovsky -
Remove the check during unbind for NR_EVENT_CHANNELS as this limits
support to less than 4096 ports.Signed-off-by: David Vrabel
Reviewed-by: Konrad Rzeszutek Wilk
Reviewed-by: Boris Ostrovsky -
In preparation for alternative event channel ABIs, move all the
functions accessing the shared data structures into their own file.Signed-off-by: David Vrabel
Reviewed-by: Konrad Rzeszutek Wilk
Reviewed-by: Boris Ostrovsky
21 Jun, 2013
1 commit
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[Purpose of this patch]
As Vaibhav explained in the thread below, tracepoints for irq vectors
are useful.http://www.spinics.net/lists/mm-commits/msg85707.html
The current interrupt traces from irq_handler_entry and irq_handler_exit
provide when an interrupt is handled. They provide good data about when
the system has switched to kernel space and how it affects the currently
running processes.There are some IRQ vectors which trigger the system into kernel space,
which are not handled in generic IRQ handlers. Tracing such events gives
us the information about IRQ interaction with other system events.The trace also tells where the system is spending its time. We want to
know which cores are handling interrupts and how they are affecting other
processes in the system. Also, the trace provides information about when
the cores are idle and which interrupts are changing that state.On the other hand, my usecase is tracing just local timer event and
getting a value of instruction pointer.I suggested to add an argument local timer event to get instruction pointer before.
But there is another way to get it with external module like systemtap.
So, I don't need to add any argument to irq vector tracepoints now.[Patch Description]
Vaibhav's patch shared a trace point ,irq_vector_entry/irq_vector_exit, in all events.
But there is an above use case to trace specific irq_vector rather than tracing all events.
In this case, we are concerned about overhead due to unwanted events.So, add following tracepoints instead of introducing irq_vector_entry/exit.
so that we can enable them independently.
- local_timer_vector
- reschedule_vector
- call_function_vector
- call_function_single_vector
- irq_work_entry_vector
- error_apic_vector
- thermal_apic_vector
- threshold_apic_vector
- spurious_apic_vector
- x86_platform_ipi_vectorAlso, introduce a logic switching IDT at enabling/disabling time so that a time penalty
makes a zero when tracepoints are disabled. Detailed explanations are as follows.
- Create trace irq handlers with entering_irq()/exiting_irq().
- Create a new IDT, trace_idt_table, at boot time by adding a logic to
_set_gate(). It is just a copy of original idt table.
- Register the new handlers for tracpoints to the new IDT by introducing
macros to alloc_intr_gate() called at registering time of irq_vector handlers.
- Add checking, whether irq vector tracing is on/off, into load_current_idt().
This has to be done below debug checking for these reasons.
- Switching to debug IDT may be kicked while tracing is enabled.
- On the other hands, switching to trace IDT is kicked only when debugging
is disabled.In addition, the new IDT is created only when CONFIG_TRACING is enabled to avoid being
used for other purposes.Signed-off-by: Seiji Aguchi
Link: http://lkml.kernel.org/r/51C323ED.5050708@hds.com
Signed-off-by: H. Peter Anvin
Cc: Steven Rostedt
17 Apr, 2013
1 commit
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For quite a few Xen versions, this wasn't the IRQ vector anymore
anyway, and it is not being used by the kernel for anything. Hence
drop the field from struct irq_info, and respective function
parameters.Signed-off-by: Jan Beulich
Acked-by: Stefano Stabellini
Signed-off-by: Konrad Rzeszutek Wilk
14 Sep, 2012
1 commit
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Compile events.c on ARM.
Parse, map and enable the IRQ to get event notifications from the device
tree (node "/xen").Signed-off-by: Stefano Stabellini
Acked-by: Konrad Rzeszutek Wilk
22 May, 2012
1 commit
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PV on HVM guests map GSIs into event channels. At restore time the
event channels are resumed by restore_pirqs.Device drivers might try to register the same GSI again through ACPI at
restore time, but the GSI has already been mapped and bound by
restore_pirqs. This patch detects these situations and avoids
mapping the same GSI multiple times.Without this patch we get:
(XEN) irq.c:2235: dom4: pirq 23 or emuirq 28 already mapped
and waste a pirq.CC: stable@kernel.org
Signed-off-by: Stefano Stabellini
Signed-off-by: Konrad Rzeszutek Wilk
22 Nov, 2011
1 commit
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Event channels exposed to userspace by the evtchn module may be used by
other modules in an asynchronous manner, which requires that reference
counting be used to prevent the event channel from being closed before
the signals are delivered.The reference count on new event channels defaults to -1 which indicates
the event channel is not referenced outside the kernel; evtchn_get fails
if called on such an event channel. The event channels made visible to
userspace by evtchn have a normal reference count.Signed-off-by: Daniel De Graaf
Signed-off-by: Konrad Rzeszutek Wilk
12 Jul, 2011
1 commit
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In the past (2.6.38) the 'xen_allocate_pirq_gsi' would allocate
an entry in a Linux IRQ -> {XEN_IRQ, type, event, ..} array. All
of that has been removed in 2.6.39 and the Xen IRQ subsystem uses
an linked list that is populated when the call to
'xen_allocate_irq_gsi' (universally done from any of the xen_bind_*
calls) is done. The 'xen_allocate_pirq_gsi' is a NOP and there is
no need for it anymore so lets remove it.Signed-off-by: Konrad Rzeszutek Wilk
14 Apr, 2011
3 commits
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We need this to find the real Xen PIRQ value for a device
that requests an MSI or MSI-X. In the past we used
'xen_gsi_from_irq' since that function would return
an Xen PIRQ or GSI depending on the provided IRQ. Now that
we have seperated that we need to use the correct
function.[v2: Deal with rebase on stable/irq.cleanup]
Signed-off-by: Konrad Rzeszutek Wilk -
We do this via the PHYSDEVOP_irq_status_query support hypervisor call.
We will get a positive value if another domain has binded its
PIRQ to the specified GSI (IRQ line).[v2: Deal with v2.6.37-rc1 rebase fallout]
[v3: Deal with stable/irq.cleanup fallout]
[v4: xen_ignore_irq->xen_test_irq_shared]
Signed-off-by: Konrad Rzeszutek Wilk -
We check if there is a domain owner for the PCI device. In case of failure
(meaning no domain has registered for this device) we make DOMID_SELF the owner.Signed-off-by: Konrad Rzeszutek Wilk
[v2: deal with rebasing on v2.6.37-1]
[v3: deal with rebasing on stable/irq.cleanup]
[v4: deal with rebasing on stable/irq.ween_of_nr_irqs]
[v5: deal with rebasing on v2.6.39-rc3]
Signed-off-by: Jeremy Fitzhardinge
Acked-by: Xiantao Zhang
18 Mar, 2011
1 commit
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…it.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/irq.fairness' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: events: Remove redundant clear of l2i at end of round-robin loop
xen: events: Make round-robin scan fairer by snapshotting each l2 word once only
xen: events: Clean up round-robin evtchn scan.
xen: events: Make last processed event channel a per-cpu variable.
xen: events: Process event channels notifications in round-robin order.* 'stable/irq.ween_of_nr_irqs' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: events: Fix compile error if CONFIG_SMP is not defined.
xen: events: correct locking in xen_irq_from_pirq
xen: events: propagate irq allocation failure instead of panicking
xen: events: do not workaround too-small nr_irqs
xen: events: remove use of nr_irqs as upper bound on number of pirqs
xen: events: dynamically allocate irq info structures
xen: events: maintain a list of Xen interrupts
xen: events: push setup of irq<->{evtchn,ipi,virq,pirq} maps into irq_info init functions
xen: events: turn irq_info constructors into initialiser functions
xen: events: use per-cpu variable for cpu_evtchn_mask
xen: events: refactor GSI pirq bindings functions
xen: events: rename restore_cpu_pirqs -> restore_pirqs
xen: events: remove unused public functions
xen: events: fix xen_map_pirq_gsi error return
xen: events: simplify comment
xen: events: separate two unrelated halves of if conditionFix up trivial conflicts in drivers/xen/events.c
17 Mar, 2011
1 commit
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* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1480 commits)
bonding: enable netpoll without checking link status
xfrm: Refcount destination entry on xfrm_lookup
net: introduce rx_handler results and logic around that
bonding: get rid of IFF_SLAVE_INACTIVE netdev->priv_flag
bonding: wrap slave state work
net: get rid of multiple bond-related netdevice->priv_flags
bonding: register slave pointer for rx_handler
be2net: Bump up the version number
be2net: Copyright notice change. Update to Emulex instead of ServerEngines
e1000e: fix kconfig for crc32 dependency
netfilter ebtables: fix xt_AUDIT to work with ebtables
xen network backend driver
bonding: Improve syslog message at device creation time
bonding: Call netif_carrier_off after register_netdevice
bonding: Incorrect TX queue offset
net_sched: fix ip_tos2prio
xfrm: fix __xfrm_route_forward()
be2net: Fix UDP packet detected status in RX compl
Phonet: fix aligned-mode pipe socket buffer header reserve
netxen: support for GbE port settings
...Fix up conflicts in drivers/staging/brcm80211/brcmsmac/wl_mac80211.c
with the staging updates.
11 Mar, 2011
8 commits
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Following the example set by xen_allocate_pirq_msi and
xen_bind_pirq_msi_to_irq:xen_allocate_pirq becomes xen_allocate_pirq_gsi and now only allocates
a pirq number and does not bind it.xen_map_pirq_gsi becomes xen_bind_pirq_gsi_to_irq and binds an
existing pirq.Signed-off-by: Ian Campbell
Signed-off-by: Konrad Rzeszutek Wilk -
I was unable to find any user of these functions in either the
functionality pending for 2.6.39 or the xen/next-2.6.32 branch of
xen.gitAn exception to this was xen_gsi_from_irq which did appear to be used
in xen/next-2.6.32's pciback. However in the 2.6.39 version of pciback
xen_pirq_from_irq is, correctly AFAICT, used instead.Only a minority of functions in events.h use "extern" so drop it from
those places for consistency.Signed-off-by: Ian Campbell
Signed-off-by: Konrad Rzeszutek Wilk -
It is never valid assume any particular relationship between a Xen
PIRQ number and and Linux IRQ number so there is no need to hedge when
saying so.Signed-off-by: Ian Campbell
Signed-off-by: Konrad Rzeszutek Wilk -
The function name does not distinguish it from xen_allocate_pirq_msi
(which operates on domU and pvhvm domains rather than dom0).Hoist domain 0 specific functionality up into the only caller leaving
functionality common to all guest types in xen_bind_pirq_msi_to_irq.Signed-off-by: Ian Campbell
Signed-off-by: Konrad Rzeszutek Wilk -
Signed-off-by: Ian Campbell
Signed-off-by: Konrad Rzeszutek Wilk -
Split the binding aspect of xen_allocate_pirq_msi out into a new
xen_bind_pirq_to_irq function.In xen_hvm_setup_msi_irq when allocating a pirq write the MSI message
to signal the PIRQ as soon as the pirq is obtained. There is no way to
free the pirq back so if the subsequent binding to an IRQ fails we
want to ensure that we will reuse the PIRQ next time rather than leak
it.Signed-off-by: Ian Campbell
Signed-off-by: Konrad Rzeszutek Wilk -
consistent with other similar functions.
Signed-off-by: Ian Campbell
Signed-off-by: Konrad Rzeszutek Wilk -
All callers pass this flag so it is pointless.
Signed-off-by: Ian Campbell
Signed-off-by: Konrad Rzeszutek Wilk
28 Feb, 2011
1 commit
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Impact: new Xen-internal API
Signed-off-by: Ian Campbell
Signed-off-by: Jeremy Fitzhardinge
Signed-off-by: Konrad Rzeszutek Wilk
02 Dec, 2010
1 commit
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When remapping MSIs into pirqs for PV on HVM guests, qemu is responsible
for doing the actual mapping and unmapping.
We only give qemu the desired pirq number when we ask to do the mapping
the first time, after that we should be reading back the pirq number
from qemu every time we want to re-enable the MSI.This fixes a bug in xen_hvm_setup_msi_irqs that manifests itself when
trying to enable the same MSI for the second time: the old MSI to pirq
mapping is still valid at this point but xen_hvm_setup_msi_irqs would
try to assign a new pirq anyway.
A simple way to reproduce this bug is to assign an MSI capable network
card to a PV on HVM guest, if the user brings down the corresponding
ethernet interface and up again, Linux would fail to enable MSIs on the
device.Signed-off-by: Stefano Stabellini
23 Oct, 2010
4 commits
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Use the console hypercalls for dom0 console.
[ Impact: Add Xen dom0 console ]
Signed-off-by: Jeremy Fitzhardinge
Signed-off-by: Juan Quintela
Signed-off-by: Stefano Stabellini
Reviewed-by: Konrad Rzeszutek Wilk -
Implement xen_create_msi_irq to create an msi and remap it as pirq.
Use xen_create_msi_irq to implement an initial domain specific version
of setup_msi_irqs.Signed-off-by: Qing He
Signed-off-by: Yunhong Jiang
Signed-off-by: Jeremy Fitzhardinge
Signed-off-by: Stefano Stabellini
Reviewed-by: Konrad Rzeszutek Wilk -
Map MSIs into pirqs, writing 0 in the MSI vector data field and the pirq
number in the MSI destination id field.Signed-off-by: Stefano Stabellini
Reviewed-by: Konrad Rzeszutek Wilk -
PHYSDEVOP_map_pirq might return a pirq different from what we asked if
we are running as an HVM guest, so we need to be able to support pirqs
that are different from linux irqs.Signed-off-by: Stefano Stabellini
Reviewed-by: Konrad Rzeszutek Wilk
18 Oct, 2010
5 commits
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The frontend stub lives in arch/x86/pci/xen.c, alongside other
sub-arch PCI init code (e.g. olpc.c).It provides a mechanism for Xen PCI frontend to setup/destroy
legacy interrupts, MSI/MSI-X, and PCI configuration operations.[ Impact: add core of Xen PCI support ]
[ v2: Removed the IOMMU code and only focusing on PCI.]
[ v3: removed usage of pci_scan_all_fns as that does not exist]
[ v4: introduced pci_xen value to fix compile warnings]
[ v5: squished fixes+features in one patch, changed Reviewed-by to Ccs]
[ v7: added Acked-by]
Signed-off-by: Alex Nixon
Signed-off-by: Jeremy Fitzhardinge
Signed-off-by: Ian Campbell
Signed-off-by: Konrad Rzeszutek Wilk
Signed-off-by: Stefano Stabellini
Acked-by: Jesse Barnes
Cc: "H. Peter Anvin"
Cc: Matthew Wilcox
Cc: Qing He
Cc: Thomas Gleixner
Cc: x86@kernel.org -
In driver/xen/events.c, whether bind_pirq is shareable or not is
determined by desc->action is NULL or not. But in __setup_irq,
startup(irq) is invoked before desc->action is assigned with
new action. So desc->action in startup_irq is always NULL, and
bind_pirq is always not shareable. This results in pt_irq_create_bind
failure when passthrough a device which shares irq to other devices.This patch doesn't use probing_irq to determine if pirq is shareable
or not, instead set shareable flag in irq_info according to trigger
mode in xen_allocate_pirq. Set level triggered interrupts shareable.
Thus use this flag to set bind_pirq flag accordingly.[v2: arch/x86/xen/pci.c no more, so file skipped]
Signed-off-by: Weidong Han
Signed-off-by: Jeremy Fitzhardinge
Signed-off-by: Konrad Rzeszutek Wilk -
The 'xen_poll_irq_timeout' provides a method to pass in
the poll timeout for IRQs if requested. We also export
those two poll functions as Xen PCI fronted uses them.Signed-off-by: Konrad Rzeszutek Wilk
Signed-off-by: Jeremy Fitzhardinge -
Impact: cleanup
Make pirq show useful information in /proc/interrupts
[v2: Removed the parts for arch/x86/xen/pci.c ]
Signed-off-by: Gerd Hoffmann
Signed-off-by: Jeremy Fitzhardinge
Signed-off-by: Konrad Rzeszutek Wilk -
A privileged PV Xen domain can get direct access to hardware. In
order for this to be useful, it must be able to get hardware
interrupts.Being a PV Xen domain, all interrupts are delivered as event channels.
PIRQ event channels are bound to a pirq number and an interrupt
vector. When a IO APIC raises a hardware interrupt on that vector, it
is delivered as an event channel, which we can deliver to the
appropriate device driver(s).This patch simply implements the infrastructure for dealing with pirq
event channels.[ Impact: integrate hardware interrupts into Xen's event scheme ]
Signed-off-by: Jeremy Fitzhardinge
Signed-off-by: Konrad Rzeszutek Wilk
23 Jul, 2010
1 commit
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Set the callback to receive evtchns from Xen, using the
callback vector delivery mechanism.The traditional way for receiving event channel notifications from Xen
is via the interrupts from the platform PCI device.
The callback vector is a newer alternative that allow us to receive
notifications on any vcpu and doesn't need any PCI support: we allocate
a vector exclusively to receive events, in the vector handler we don't
need to interact with the vlapic, therefore we avoid a VMEXIT.Signed-off-by: Stefano Stabellini
Signed-off-by: Sheng Yang
Signed-off-by: Jeremy Fitzhardinge
31 Mar, 2009
1 commit
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Given an evtchn, return the corresponding irq.
Signed-off-by: Ian Campbell
Signed-off-by: Jeremy Fitzhardinge
21 Aug, 2008
1 commit
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A spinlock can be interrupted while spinning, so make sure we preserve
the previous lock of interest if we're taking a lock from within an
interrupt handler.We also need to deal with the case where the blocking path gets
interrupted between testing to see if the lock is free and actually
blocking. If we get interrupted there and end up in the state where
the lock is free but the irq isn't pending, then we'll block
indefinitely in the hypervisor. This fix is to make sure that any
nested lock-takers will always leave the irq pending if there's any
chance the outer lock became free.Signed-off-by: Jeremy Fitzhardinge
Acked-by: Jan Beulich
Signed-off-by: Ingo Molnar
