<feed xmlns='http://www.w3.org/2005/Atom'>
<title>lwn.git/virt/kvm/irq_comm.c, branch v3.19.1</title>
<subtitle>Linux kernel documentation tree maintained by Jonathan Corbet</subtitle>
<id>http://mirrors.hust.edu.cn/git/lwn.git/atom?h=v3.19.1</id>
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<updated>2014-11-21T17:02:37+00:00</updated>
<entry>
<title>kvm: x86: move ioapic.c and irq_comm.c back to arch/x86/</title>
<updated>2014-11-21T17:02:37+00:00</updated>
<author>
<name>Paolo Bonzini</name>
<email>pbonzini@redhat.com</email>
</author>
<published>2014-11-20T12:45:31+00:00</published>
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<id>urn:sha1:6ef768fac9dfe3404d3fdc09909ea203a88f2f38</id>
<content type='text'>
ia64 does not need them anymore.  Ack notifiers become x86-specific
too.

Suggested-by: Gleb Natapov &lt;gleb@kernel.org&gt;
Reviewed-by: Radim Krcmar &lt;rkrcmar@redhat.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
</content>
</entry>
<entry>
<title>KVM: ia64: remove</title>
<updated>2014-11-20T10:08:33+00:00</updated>
<author>
<name>Paolo Bonzini</name>
<email>pbonzini@redhat.com</email>
</author>
<published>2014-11-19T15:22:52+00:00</published>
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<id>urn:sha1:003f7de6258900e17f6206e8e417d76c75ca549f</id>
<content type='text'>
KVM for ia64 has been marked as broken not just once, but twice even,
and the last patch from the maintainer is now roughly 5 years old.
Time for it to rest in peace.

Acked-by: Gleb Natapov &lt;gleb@kernel.org&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
</content>
</entry>
<entry>
<title>KVM: Move all accesses to kvm::irq_routing into irqchip.c</title>
<updated>2014-08-05T12:26:20+00:00</updated>
<author>
<name>Paul Mackerras</name>
<email>paulus@samba.org</email>
</author>
<published>2014-06-30T10:51:11+00:00</published>
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<id>urn:sha1:9957c86d659a4d5a2bed25ccbd3bfc9c3f25e658</id>
<content type='text'>
Now that struct _irqfd does not keep a reference to storage pointed
to by the irq_routing field of struct kvm, we can move the statement
that updates it out from under the irqfds.lock and put it in
kvm_set_irq_routing() instead.  That means we then have to take a
srcu_read_lock on kvm-&gt;irq_srcu around the irqfd_update call in
kvm_irqfd_assign(), since holding the kvm-&gt;irqfds.lock no longer
ensures that that the routing can't change.

Combined with changing kvm_irq_map_gsi() and kvm_irq_map_chip_pin()
to take a struct kvm * argument instead of the pointer to the routing
table, this allows us to to move all references to kvm-&gt;irq_routing
into irqchip.c.  That in turn allows us to move the definition of the
kvm_irq_routing_table struct into irqchip.c as well.

Signed-off-by: Paul Mackerras &lt;paulus@samba.org&gt;
Tested-by: Eric Auger &lt;eric.auger@linaro.org&gt;
Tested-by: Cornelia Huck &lt;cornelia.huck@de.ibm.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
</content>
</entry>
<entry>
<title>KVM: irqchip: Provide and use accessors for irq routing table</title>
<updated>2014-08-05T12:26:16+00:00</updated>
<author>
<name>Paul Mackerras</name>
<email>paulus@samba.org</email>
</author>
<published>2014-06-30T10:51:10+00:00</published>
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<id>urn:sha1:8ba918d488caded2c4368b0b922eb905fe3bb101</id>
<content type='text'>
This provides accessor functions for the KVM interrupt mappings, in
order to reduce the amount of code that accesses the fields of the
kvm_irq_routing_table struct, and restrict that code to one file,
virt/kvm/irqchip.c.  The new functions are kvm_irq_map_gsi(), which
maps from a global interrupt number to a set of IRQ routing entries,
and kvm_irq_map_chip_pin, which maps from IRQ chip and pin numbers to
a global interrupt number.

This also moves the update of kvm_irq_routing_table::chip[][]
into irqchip.c, out of the various kvm_set_routing_entry
implementations.  That means that none of the kvm_set_routing_entry
implementations need the kvm_irq_routing_table argument anymore,
so this removes it.

This does not change any locking or data lifetime rules.

Signed-off-by: Paul Mackerras &lt;paulus@samba.org&gt;
Tested-by: Eric Auger &lt;eric.auger@linaro.org&gt;
Tested-by: Cornelia Huck &lt;cornelia.huck@de.ibm.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
</content>
</entry>
<entry>
<title>kvm: Resolve missing-field-initializers warnings</title>
<updated>2014-07-25T14:05:46+00:00</updated>
<author>
<name>Mark Rustad</name>
<email>mark.d.rustad@intel.com</email>
</author>
<published>2014-07-25T13:27:03+00:00</published>
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<id>urn:sha1:25f97ff451a4aab534afc1290af97d23ea0b4fb3</id>
<content type='text'>
Resolve missing-field-initializers warnings seen in W=2 kernel
builds by having macros generate more elaborated initializers.
That is enough to silence the warnings.

Signed-off-by: Mark Rustad &lt;mark.d.rustad@intel.com&gt;
Signed-off-by: Jeff Kirsher &lt;jeffrey.t.kirsher@intel.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
</content>
</entry>
<entry>
<title>kvm/irqchip: Speed up KVM_SET_GSI_ROUTING</title>
<updated>2014-05-05T14:29:11+00:00</updated>
<author>
<name>Christian Borntraeger</name>
<email>borntraeger@de.ibm.com</email>
</author>
<published>2014-01-16T12:44:20+00:00</published>
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<id>urn:sha1:719d93cd5f5c5c8775b7a38192069e8e1d1ac46e</id>
<content type='text'>
When starting lots of dataplane devices the bootup takes very long on
Christian's s390 with irqfd patches. With larger setups he is even
able to trigger some timeouts in some components.  Turns out that the
KVM_SET_GSI_ROUTING ioctl takes very long (strace claims up to 0.1 sec)
when having multiple CPUs.  This is caused by the  synchronize_rcu and
the HZ=100 of s390.  By changing the code to use a private srcu we can
speed things up.  This patch reduces the boot time till mounting root
from 8 to 2 seconds on my s390 guest with 100 disks.

Uses of hlist_for_each_entry_rcu, hlist_add_head_rcu, hlist_del_init_rcu
are fine because they do not have lockdep checks (hlist_for_each_entry_rcu
uses rcu_dereference_raw rather than rcu_dereference, and write-sides
do not do rcu lockdep at all).

Note that we're hardly relying on the "sleepable" part of srcu.  We just
want SRCU's faster detection of grace periods.

Testing was done by Andrew Theurer using netperf tests STREAM, MAERTS
and RR.  The difference between results "before" and "after" the patch
has mean -0.2% and standard deviation 0.6%.  Using a paired t-test on the
data points says that there is a 2.5% probability that the patch is the
cause of the performance difference (rather than a random fluctuation).

(Restricting the t-test to RR, which is the most likely to be affected,
changes the numbers to respectively -0.3% mean, 0.7% stdev, and 8%
probability that the numbers actually say something about the patch.
The probability increases mostly because there are fewer data points).

Cc: Marcelo Tosatti &lt;mtosatti@redhat.com&gt;
Cc: Michael S. Tsirkin &lt;mst@redhat.com&gt;
Tested-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt; # s390
Reviewed-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
</content>
</entry>
<entry>
<title>KVM: Move irq routing setup to irqchip.c</title>
<updated>2013-04-26T18:27:18+00:00</updated>
<author>
<name>Alexander Graf</name>
<email>agraf@suse.de</email>
</author>
<published>2013-04-15T21:23:21+00:00</published>
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<id>urn:sha1:e8cde0939d8ebe9c8ebe5a4bdf71af51a0d56053</id>
<content type='text'>
Setting up IRQ routes is nothing IOAPIC specific. Extract everything
that really is generic code into irqchip.c and only leave the ioapic
specific bits to irq_comm.c.

Signed-off-by: Alexander Graf &lt;agraf@suse.de&gt;
Acked-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
</content>
</entry>
<entry>
<title>KVM: Extract generic irqchip logic into irqchip.c</title>
<updated>2013-04-26T18:27:17+00:00</updated>
<author>
<name>Alexander Graf</name>
<email>agraf@suse.de</email>
</author>
<published>2013-04-15T21:04:10+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=1c9f8520bda73c07fed9bcdb307854b45a3a60c4'/>
<id>urn:sha1:1c9f8520bda73c07fed9bcdb307854b45a3a60c4</id>
<content type='text'>
The current irq_comm.c file contains pieces of code that are generic
across different irqchip implementations, as well as code that is
fully IOAPIC specific.

Split the generic bits out into irqchip.c.

Signed-off-by: Alexander Graf &lt;agraf@suse.de&gt;
Acked-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
</content>
</entry>
<entry>
<title>KVM: Add KVM_IRQCHIP_NUM_PINS in addition to KVM_IOAPIC_NUM_PINS</title>
<updated>2013-04-26T18:27:13+00:00</updated>
<author>
<name>Alexander Graf</name>
<email>agraf@suse.de</email>
</author>
<published>2013-04-15T08:42:33+00:00</published>
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<id>urn:sha1:8175e5b79c38a1d85225da516fa1a0ecbf2fdbca</id>
<content type='text'>
The concept of routing interrupt lines to an irqchip is nothing
that is IOAPIC specific. Every irqchip has a maximum number of pins
that can be linked to irq lines.

So let's add a new define that allows us to reuse generic code for
non-IOAPIC platforms.

Signed-off-by: Alexander Graf &lt;agraf@suse.de&gt;
Acked-by: Michael S. Tsirkin &lt;mst@redhat.com&gt;
</content>
</entry>
<entry>
<title>KVM: Call common update function when ioapic entry changed.</title>
<updated>2013-04-16T19:32:40+00:00</updated>
<author>
<name>Yang Zhang</name>
<email>yang.z.zhang@Intel.com</email>
</author>
<published>2013-04-11T11:25:13+00:00</published>
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<id>urn:sha1:3d81bc7e96d6bca0b8f8b7d1bf6ea72caa3aac57</id>
<content type='text'>
Both TMR and EOI exit bitmap need to be updated when ioapic changed
or vcpu's id/ldr/dfr changed. So use common function instead eoi exit
bitmap specific function.

Signed-off-by: Yang Zhang &lt;yang.z.zhang@Intel.com&gt;
Reviewed-by: Gleb Natapov &lt;gleb@redhat.com&gt;
Signed-off-by: Marcelo Tosatti &lt;mtosatti@redhat.com&gt;
</content>
</entry>
</feed>
