linux.git/kernel/irq/msi.c, branch v4.13

genirq/irqdomain: Remove auto-recursive hierarchy support

2017-06-22T16:29:34+00:00

It did seem like a good idea at the time, but it never really
caught on, and auto-recursive domains remain unused 3 years after
having been introduced.

Oh well, time for a late spring cleanup.

Signed-off-by: Marc Zyngier 
Signed-off-by: Thomas Gleixner

genirq/msi: Prevent overwriting domain name

2017-06-22T16:21:08+00:00

Prevent overwriting an already assigned domain name. Remove the extra check
for chip->name, because if domain->name is NULL overwriting it with NULL is
not a problem.

Signed-off-by: Thomas Gleixner 
Acked-by: Marc Zyngier 
Cc: Jens Axboe 
Cc: Michael Ellerman 
Cc: Keith Busch 
Cc: Peter Zijlstra 
Cc: Christoph Hellwig 
Link: http://lkml.kernel.org/r/20170619235443.510684976@linutronix.de

genirq/msi: Populate the domain name if provided by the irqchip

2017-05-22T20:29:45+00:00

In order to ease debug, let's populate the domain name upfront, before any
MSI gets requested. This allows the domain to appear in the
irq_domain_mapping, and the user to easily find the expected data.

Signed-off-by: Marc Zyngier 
Link: http://lkml.kernel.org/r/20170512115538.10767-4-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner

genirq/msi: Set IRQ_DOMAIN_FLAG_MSI on MSI domain creation

2017-01-23T15:00:45+00:00

Now we have a flag value indicating an IRQ domain implements MSI,
let's set it on msi_create_irq_domain().

Signed-off-by: Eric Auger 
Reviewed-by: Marc Zyngier 
Tested-by: Tomasz Nowicki 
Tested-by: Bharat Bhushan 
Signed-off-by: Will Deacon

genirq/msi: Drop artificial PCI dependency

2016-11-22T10:00:19+00:00

The generic MSI layer doesn't have any PCI ties anymore, and the
build hack should have been removed some time ago.

Fixes: d9109698be6e ("genirq: Introduce msi_domain_alloc/free_irqs()")
Signed-off-by: Marc Zyngier 
Link: http://lkml.kernel.org/r/1479806476-20801-1-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner

genirq/msi: Add cpumask allocation to alloc_msi_entry

2016-09-14T20:11:08+00:00

For irq spreading want to store affinity masks in the msi_entry. Add the
infrastructure for it.

We allocate an array of cpumasks with an array size of the number of used
vectors in the entry, so we can hand in the information per linux interrupt
later.

As we hand in the number of used vectors, we assign them right
away. Convert all the call sites.

Signed-off-by: Thomas Gleixner 
Cc: axboe@fb.com
Cc: keith.busch@intel.com
Cc: agordeev@redhat.com
Cc: linux-block@vger.kernel.org
Cc: Christoph Hellwig 
Link: http://lkml.kernel.org/r/1473862739-15032-2-git-send-email-hch@lst.de

genirq/msi: Make sure PCI MSIs are activated early

2016-08-09T07:19:32+00:00

Bharat Kumar Gogada reported issues with the generic MSI code, where the
end-point ended up with garbage in its MSI configuration (both for the vector
and the message).

It turns out that the two MSI paths in the kernel are doing slightly different
things:

generic MSI: disable MSI -> allocate MSI -> enable MSI -> setup EP
PCI MSI: disable MSI -> allocate MSI -> setup EP -> enable MSI

And it turns out that end-points are allowed to latch the content of the MSI
configuration registers as soon as MSIs are enabled.  In Bharat's case, the
end-point ends up using whatever was there already, which is not what you
want.

In order to make things converge, we introduce a new MSI domain flag
(MSI_FLAG_ACTIVATE_EARLY) that is unconditionally set for PCI/MSI. When set,
this flag forces the programming of the end-point as soon as the MSIs are
allocated.

A consequence of this is that we have an extra activate in irq_startup, but
that should be without much consequence.

tglx: 

 - Several people reported a VMWare regression with PCI/MSI-X passthrough. It
   turns out that the patch also cures that issue.

 - We need to have a look at the MSI disable interrupt path, where we write
   the msg to all zeros without disabling MSI in the PCI device. Is that
   correct?

Fixes: 52f518a3a7c2 "x86/MSI: Use hierarchical irqdomains to manage MSI interrupts"
Reported-and-tested-by: Bharat Kumar Gogada 
Reported-and-tested-by: Foster Snowhill 
Reported-by: Matthias Prager 
Reported-by: Jason Taylor 
Signed-off-by: Marc Zyngier 
Acked-by: Bjorn Helgaas 
Cc: linux-pci@vger.kernel.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1468426713-31431-1-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner

genirq/msi: Fix broken debug output

2016-07-04T13:32:25+00:00

virq is not required to be the same for all msi descs. Use the base irq number
from the desc in the debug printk.

Reported-by: Ingo Molnar 
Signed-off-by: Thomas Gleixner

genirq/msi: Make use of affinity aware allocations

2016-07-04T10:25:14+00:00

Allow the MSI code to provide affinity hints per MSI descriptor.

Signed-off-by: Thomas Gleixner 
Cc: Christoph Hellwig 
Cc: linux-block@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: linux-nvme@lists.infradead.org
Cc: axboe@fb.com
Cc: agordeev@redhat.com
Link: http://lkml.kernel.org/r/1467621574-8277-6-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner

genirq: Add affinity hint to irq allocation

2016-07-04T10:25:13+00:00

Add an extra argument to the irq(domain) allocation functions, so we can hand
down affinity hints to the allocator. Thats necessary to implement proper
support for multiqueue devices.

Signed-off-by: Thomas Gleixner 
Cc: Christoph Hellwig 
Cc: linux-block@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: linux-nvme@lists.infradead.org
Cc: axboe@fb.com
Cc: agordeev@redhat.com
Link: http://lkml.kernel.org/r/1467621574-8277-4-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner