Commit Graph

35 Commits

Author SHA1 Message Date
Minwoo Im 0e51833042 genirq/affinity: Remove unused argument from [__]irq_build_affinity_masks()
The *affd argument is neither used in irq_build_affinity_masks() nor
__irq_build_affinity_masks(). Remove it.

Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Minwoo Im <minwoo.im@samsung.com>
Cc: linux-block@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602112117.31839-1-minwoo.im.dev@gmail.com
2019-06-12 10:52:45 +02:00
Thomas Gleixner a6a309edba genirq/affinity: Remove the leftovers of the original set support
Now that the NVME driver is converted over to the calc_set() callback, the
workarounds of the original set support can be removed.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: linux-nvme@lists.infradead.org
Cc: linux-pci@vger.kernel.org
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sumit Saxena <sumit.saxena@broadcom.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Shivasharan Srikanteshwara <shivasharan.srikanteshwara@broadcom.com>
Link: https://lkml.kernel.org/r/20190216172228.689834224@linutronix.de
2019-02-18 11:21:29 +01:00
Ming Lei c66d4bd110 genirq/affinity: Add new callback for (re)calculating interrupt sets
The interrupt affinity spreading mechanism supports to spread out
affinities for one or more interrupt sets. A interrupt set contains one or
more interrupts. Each set is mapped to a specific functionality of a
device, e.g. general I/O queues and read I/O queus of multiqueue block
devices.

The number of interrupts per set is defined by the driver. It depends on
the total number of available interrupts for the device, which is
determined by the PCI capabilites and the availability of underlying CPU
resources, and the number of queues which the device provides and the
driver wants to instantiate.

The driver passes initial configuration for the interrupt allocation via a
pointer to struct irq_affinity.

Right now the allocation mechanism is complex as it requires to have a loop
in the driver to determine the maximum number of interrupts which are
provided by the PCI capabilities and the underlying CPU resources.  This
loop would have to be replicated in every driver which wants to utilize
this mechanism. That's unwanted code duplication and error prone.

In order to move this into generic facilities it is required to have a
mechanism, which allows the recalculation of the interrupt sets and their
size, in the core code. As the core code does not have any knowledge about the
underlying device, a driver specific callback is required in struct
irq_affinity, which can be invoked by the core code. The callback gets the
number of available interupts as an argument, so the driver can calculate the
corresponding number and size of interrupt sets.

At the moment the struct irq_affinity pointer which is handed in from the
driver and passed through to several core functions is marked 'const', but for
the callback to be able to modify the data in the struct it's required to
remove the 'const' qualifier.

Add the optional callback to struct irq_affinity, which allows drivers to
recalculate the number and size of interrupt sets and remove the 'const'
qualifier.

For simple invocations, which do not supply a callback, a default callback
is installed, which just sets nr_sets to 1 and transfers the number of
spreadable vectors to the set_size array at index 0.

This is for now guarded by a check for nr_sets != 0 to keep the NVME driver
working until it is converted to the callback mechanism.

To make sure that the driver configuration is correct under all circumstances
the callback is invoked even when there are no interrupts for queues left,
i.e. the pre/post requirements already exhaust the numner of available
interrupts.

At the PCI layer irq_create_affinity_masks() has to be invoked even for the
case where the legacy interrupt is used. That ensures that the callback is
invoked and the device driver can adjust to that situation.

[ tglx: Fixed the simple case (no sets required). Moved the sanity check
  	for nr_sets after the invocation of the callback so it catches
  	broken drivers. Fixed the kernel doc comments for struct
  	irq_affinity and de-'This patch'-ed the changelog ]

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: linux-nvme@lists.infradead.org
Cc: linux-pci@vger.kernel.org
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sumit Saxena <sumit.saxena@broadcom.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Shivasharan Srikanteshwara <shivasharan.srikanteshwara@broadcom.com>
Link: https://lkml.kernel.org/r/20190216172228.512444498@linutronix.de
2019-02-18 11:21:28 +01:00
Ming Lei 9cfef55bb5 genirq/affinity: Store interrupt sets size in struct irq_affinity
The interrupt affinity spreading mechanism supports to spread out
affinities for one or more interrupt sets. A interrupt set contains one
or more interrupts. Each set is mapped to a specific functionality of a
device, e.g. general I/O queues and read I/O queus of multiqueue block
devices.

The number of interrupts per set is defined by the driver. It depends on
the total number of available interrupts for the device, which is
determined by the PCI capabilites and the availability of underlying CPU
resources, and the number of queues which the device provides and the
driver wants to instantiate.

The driver passes initial configuration for the interrupt allocation via
a pointer to struct irq_affinity.

Right now the allocation mechanism is complex as it requires to have a
loop in the driver to determine the maximum number of interrupts which
are provided by the PCI capabilities and the underlying CPU resources.
This loop would have to be replicated in every driver which wants to
utilize this mechanism. That's unwanted code duplication and error
prone.

In order to move this into generic facilities it is required to have a
mechanism, which allows the recalculation of the interrupt sets and
their size, in the core code. As the core code does not have any
knowledge about the underlying device, a driver specific callback will
be added to struct affinity_desc, which will be invoked by the core
code. The callback will get the number of available interupts as an
argument, so the driver can calculate the corresponding number and size
of interrupt sets.

To support this, two modifications for the handling of struct irq_affinity
are required:

1) The (optional) interrupt sets size information is contained in a
   separate array of integers and struct irq_affinity contains a
   pointer to it.

   This is cumbersome and as the maximum number of interrupt sets is small,
   there is no reason to have separate storage. Moving the size array into
   struct affinity_desc avoids indirections and makes the code simpler.

2) At the moment the struct irq_affinity pointer which is handed in from
   the driver and passed through to several core functions is marked
   'const'.

   With the upcoming callback to recalculate the number and size of
   interrupt sets, it's necessary to remove the 'const'
   qualifier. Otherwise the callback would not be able to update the data.

Implement #1 and store the interrupt sets size in 'struct irq_affinity'.

No functional change.

[ tglx: Fixed the memcpy() size so it won't copy beyond the size of the
  	source. Fixed the kernel doc comments for struct irq_affinity and
  	de-'This patch'-ed the changelog ]

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: linux-nvme@lists.infradead.org
Cc: linux-pci@vger.kernel.org
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sumit Saxena <sumit.saxena@broadcom.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Shivasharan Srikanteshwara <shivasharan.srikanteshwara@broadcom.com>
Link: https://lkml.kernel.org/r/20190216172228.423723127@linutronix.de
2019-02-18 11:21:27 +01:00
Thomas Gleixner 0145c30e89 genirq/affinity: Code consolidation
All information and calculations in the interrupt affinity spreading code
is strictly unsigned int. Though the code uses int all over the place.

Convert it over to unsigned int.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bjorn Helgaas <helgaas@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: linux-nvme@lists.infradead.org
Cc: linux-pci@vger.kernel.org
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sumit Saxena <sumit.saxena@broadcom.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Shivasharan Srikanteshwara <shivasharan.srikanteshwara@broadcom.com>
Link: https://lkml.kernel.org/r/20190216172228.336424556@linutronix.de
2019-02-18 11:21:27 +01:00
Ming Lei 347253c42d genirq/affinity: Move allocation of 'node_to_cpumask' to irq_build_affinity_masks()
'node_to_cpumask' is just one temparay variable for irq_build_affinity_masks(),
so move it into irq_build_affinity_masks().

No functioanl change.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: linux-nvme@lists.infradead.org
Cc: linux-pci@vger.kernel.org
Link: https://lkml.kernel.org/r/20190125095347.17950-2-ming.lei@redhat.com
2019-02-10 19:53:55 +01:00
Dou Liyang c410abbbac genirq/affinity: Add is_managed to struct irq_affinity_desc
Devices which use managed interrupts usually have two classes of
interrupts:

  - Interrupts for multiple device queues
  - Interrupts for general device management

Currently both classes are treated the same way, i.e. as managed
interrupts. The general interrupts get the default affinity mask assigned
while the device queue interrupts are spread out over the possible CPUs.

Treating the general interrupts as managed is both a limitation and under
certain circumstances a bug. Assume the following situation:

 default_irq_affinity = 4..7

So if CPUs 4-7 are offlined, then the core code will shut down the device
management interrupts because the last CPU in their affinity mask went
offline.

It's also a limitation because it's desired to allow manual placement of
the general device interrupts for various reasons. If they are marked
managed then the interrupt affinity setting from both user and kernel space
is disabled. That limitation was reported by Kashyap and Sumit.

Expand struct irq_affinity_desc with a new bit 'is_managed' which is set
for truly managed interrupts (queue interrupts) and cleared for the general
device interrupts.

[ tglx: Simplify code and massage changelog ]

Reported-by: Kashyap Desai <kashyap.desai@broadcom.com>
Reported-by: Sumit Saxena <sumit.saxena@broadcom.com>
Signed-off-by: Dou Liyang <douliyangs@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-pci@vger.kernel.org
Cc: shivasharan.srikanteshwara@broadcom.com
Cc: ming.lei@redhat.com
Cc: hch@lst.de
Cc: bhelgaas@google.com
Cc: douliyang1@huawei.com
Link: https://lkml.kernel.org/r/20181204155122.6327-3-douliyangs@gmail.com
2018-12-19 11:32:08 +01:00
Dou Liyang bec04037e4 genirq/core: Introduce struct irq_affinity_desc
The interrupt affinity management uses straight cpumask pointers to convey
the automatically assigned affinity masks for managed interrupts. The core
interrupt descriptor allocation also decides based on the pointer being non
NULL whether an interrupt is managed or not.

Devices which use managed interrupts usually have two classes of
interrupts:

  - Interrupts for multiple device queues
  - Interrupts for general device management

Currently both classes are treated the same way, i.e. as managed
interrupts. The general interrupts get the default affinity mask assigned
while the device queue interrupts are spread out over the possible CPUs.

Treating the general interrupts as managed is both a limitation and under
certain circumstances a bug. Assume the following situation:

 default_irq_affinity = 4..7

So if CPUs 4-7 are offlined, then the core code will shut down the device
management interrupts because the last CPU in their affinity mask went
offline.

It's also a limitation because it's desired to allow manual placement of
the general device interrupts for various reasons. If they are marked
managed then the interrupt affinity setting from both user and kernel space
is disabled.

To remedy that situation it's required to convey more information than the
cpumasks through various interfaces related to interrupt descriptor
allocation.

Instead of adding yet another argument, create a new data structure
'irq_affinity_desc' which for now just contains the cpumask. This struct
can be expanded to convey auxilliary information in the next step.

No functional change, just preparatory work.

[ tglx: Simplified logic and clarified changelog ]

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Dou Liyang <douliyangs@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-pci@vger.kernel.org
Cc: kashyap.desai@broadcom.com
Cc: shivasharan.srikanteshwara@broadcom.com
Cc: sumit.saxena@broadcom.com
Cc: ming.lei@redhat.com
Cc: hch@lst.de
Cc: douliyang1@huawei.com
Link: https://lkml.kernel.org/r/20181204155122.6327-2-douliyangs@gmail.com
2018-12-19 11:32:08 +01:00
Thomas Gleixner c2899c3470 genirq/affinity: Remove excess indentation
Plus other coding style issues which stood out while staring at that code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-12-19 11:32:07 +01:00
Jens Axboe 6da4b3ab9a genirq/affinity: Add support for allocating interrupt sets
A driver may have a need to allocate multiple sets of MSI/MSI-X interrupts,
and have them appropriately affinitized.

Add support for defining a number of sets in the irq_affinity structure, of
varying sizes, and get each set affinitized correctly across the machine.

[ tglx: Minor changelog tweaks ]

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Cc: linux-block@vger.kernel.org
Link: https://lkml.kernel.org/r/20181102145951.31979-5-ming.lei@redhat.com
2018-11-05 12:16:27 +01:00
Ming Lei 060746d9e3 genirq/affinity: Pass first vector to __irq_build_affinity_masks()
No functional change.

Prepares for support of allocating and affinitizing sets of interrupts, in
which each set of interrupts needs a full two stage spreading. The first
vector argument is necessary for this so the affinitizing starts from the
first vector of each set.

[ tglx: Minor changelog tweaks ]

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Hannes Reinecke <hare@suse.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Link: https://lkml.kernel.org/r/20181102145951.31979-4-ming.lei@redhat.com
2018-11-05 12:16:26 +01:00
Ming Lei 5c903e108d genirq/affinity: Move two stage affinity spreading into a helper function
No functional change. Prepares for supporting allocating and affinitizing
interrupt sets.

[ tglx: Minor changelog tweaks ]

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Hannes Reinecke <hare@suse.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Link: https://lkml.kernel.org/r/20181102145951.31979-3-ming.lei@redhat.com
2018-11-05 12:16:26 +01:00
Long Li b825921990 genirq/affinity: Spread IRQs to all available NUMA nodes
If the number of NUMA nodes exceeds the number of MSI/MSI-X interrupts
which are allocated for a device, the interrupt affinity spreading code
fails to spread them across all nodes.

The reason is, that the spreading code starts from node 0 and continues up
to the number of interrupts requested for allocation. This leaves the nodes
past the last interrupt unused.

This results in interrupt concentration on the first nodes which violates
the assumption of the block layer that all nodes are covered evenly. As a
consequence the NUMA nodes above the number of interrupts are all assigned
to hardware queue 0 and therefore NUMA node 0, which results in bad
performance and has CPU hotplug implications, because queue 0 gets shut
down when the last CPU of node 0 is offlined.

Go over all NUMA nodes and assign them round-robin to all requested
interrupts to solve this.

[ tglx: Massaged changelog ]

Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Michael Kelley <mikelley@microsoft.com>
Link: https://lkml.kernel.org/r/20181102180248.13583-1-longli@linuxonhyperv.com
2018-11-05 12:16:26 +01:00
Ming Lei d3056812e7 genirq/affinity: Spread irq vectors among present CPUs as far as possible
Commit 84676c1f21 ("genirq/affinity: assign vectors to all possible CPUs")
tried to spread the interrupts accross all possible CPUs to make sure that
in case of phsyical hotplug (e.g. virtualization) the CPUs which get
plugged in after the device was initialized are targeted by a hardware
queue and the corresponding interrupt.

This has a downside in cases where the ACPI tables claim that there are
more possible CPUs than present CPUs and the number of interrupts to spread
out is smaller than the number of possible CPUs. These bogus ACPI tables
are unfortunately not uncommon.

In such a case the vector spreading algorithm assigns interrupts to CPUs
which can never be utilized and as a consequence these interrupts are
unused instead of being mapped to present CPUs. As a result the performance
of the device is suboptimal.

To fix this spread the interrupt vectors in two stages:

 1) Spread as many interrupts as possible among the present CPUs

 2) Spread the remaining vectors among non present CPUs

On a 8 core system, where CPU 0-3 are present and CPU 4-7 are not present,
for a device with 4 queues the resulting interrupt affinity is:

  1) Before 84676c1f21 ("genirq/affinity: assign vectors to all possible CPUs")
	irq 39, cpu list 0
	irq 40, cpu list 1
	irq 41, cpu list 2
	irq 42, cpu list 3

  2) With 84676c1f21 ("genirq/affinity: assign vectors to all possible CPUs")
	irq 39, cpu list 0-2
	irq 40, cpu list 3-4,6
	irq 41, cpu list 5
	irq 42, cpu list 7

  3) With the refined vector spread applied:
	irq 39, cpu list 0,4
	irq 40, cpu list 1,6
	irq 41, cpu list 2,5
	irq 42, cpu list 3,7

On a 8 core system, where all CPUs are present the resulting interrupt
affinity for the 4 queues is:

	irq 39, cpu list 0,1
	irq 40, cpu list 2,3
	irq 41, cpu list 4,5
	irq 42, cpu list 6,7

This is independent of the number of CPUs which are online at the point of
initialization because in such a system the offline CPUs can be easily
onlined afterwards, while in non-present CPUs need to be plugged physically
or virtually which requires external interaction.

The downside of this approach is that in case of physical hotplug the
interrupt vector spreading might be suboptimal when CPUs 4-7 are physically
plugged. Suboptimal from a NUMA point of view and due to the single target
nature of interrupt affinities the later plugged CPUs might not be targeted
by interrupts at all.

Though, physical hotplug systems are not the common case while the broken
ACPI table disease is wide spread. So it's preferred to have as many
interrupts as possible utilized at the point where the device is
initialized.

Block multi-queue devices like NVME create a hardware queue per possible
CPU, so the goal of commit 84676c1f21 to assign one interrupt vector per
possible CPU is still achieved even with physical/virtual hotplug.

[ tglx: Changed from online to present CPUs for the first spreading stage,
  	renamed variables for readability sake, added comments and massaged
  	changelog ]

Reported-by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Link: https://lkml.kernel.org/r/20180308105358.1506-5-ming.lei@redhat.com
2018-04-06 12:19:51 +02:00
Ming Lei 1a2d0914e2 genirq/affinity: Allow irq spreading from a given starting point
To support two stage irq vector spreading, it's required to add a starting
point to the spreading function. No functional change, just preparatory
work for the actual two stage change.

[ tglx: Renamed variables, tidied up the code and massaged changelog ]

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Laurence Oberman <loberman@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Link: https://lkml.kernel.org/r/20180308105358.1506-4-ming.lei@redhat.com
2018-04-06 12:19:51 +02:00
Ming Lei b3e6aaa8d9 genirq/affinity: Move actual irq vector spreading into a helper function
No functional change, just prepare for converting to 2-stage irq vector
spreading.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Laurence Oberman <loberman@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Link: https://lkml.kernel.org/r/20180308105358.1506-3-ming.lei@redhat.com
2018-04-06 12:19:51 +02:00
Ming Lei 47778f33dc genirq/affinity: Rename *node_to_possible_cpumask as *node_to_cpumask
The following patches will introduce two stage irq spreading for improving
irq spread on all possible CPUs.

No functional change.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Laurence Oberman <loberman@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Link: https://lkml.kernel.org/r/20180308105358.1506-2-ming.lei@redhat.com
2018-04-06 12:19:50 +02:00
Thomas Gleixner 0211e12dd0 genirq/affinity: Don't return with empty affinity masks on error
When the allocation of node_to_possible_cpumask fails, then
irq_create_affinity_masks() returns with a pointer to the empty affinity
masks array, which will cause malfunction.

Reorder the allocations so the masks array allocation comes last and every
failure path returns NULL.

Fixes: 9a0ef98e18 ("genirq/affinity: Assign vectors to all present CPUs")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ming Lei <ming.lei@redhat.com>
2018-04-06 12:19:50 +02:00
Christoph Hellwig 84676c1f21 genirq/affinity: assign vectors to all possible CPUs
Currently we assign managed interrupt vectors to all present CPUs.  This
works fine for systems were we only online/offline CPUs.  But in case of
systems that support physical CPU hotplug (or the virtualized version of
it) this means the additional CPUs covered for in the ACPI tables or on
the command line are not catered for.  To fix this we'd either need to
introduce new hotplug CPU states just for this case, or we can start
assining vectors to possible but not present CPUs.

Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Stefan Haberland <sth@linux.vnet.ibm.com>
Fixes: 4b855ad371 ("blk-mq: Create hctx for each present CPU")
Cc: linux-kernel@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-01-12 11:01:38 -07:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Linus Torvalds f263fbb8d6 pci-v4.13-changes
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Merge tag 'pci-v4.13-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:

  - add sysfs max_link_speed/width, current_link_speed/width (Wong Vee
    Khee)

  - make host bridge IRQ mapping much more generic (Matthew Minter,
    Lorenzo Pieralisi)

  - convert most drivers to pci_scan_root_bus_bridge() (Lorenzo
    Pieralisi)

  - mutex sriov_configure() (Jakub Kicinski)

  - mutex pci_error_handlers callbacks (Christoph Hellwig)

  - split ->reset_notify() into ->reset_prepare()/reset_done()
    (Christoph Hellwig)

  - support multiple PCIe portdrv interrupts for MSI as well as MSI-X
    (Gabriele Paoloni)

  - allocate MSI/MSI-X vector for Downstream Port Containment (Gabriele
    Paoloni)

  - fix MSI IRQ affinity pre/post/min_vecs issue (Michael Hernandez)

  - test INTx masking during enumeration, not at run-time (Piotr Gregor)

  - avoid using device_may_wakeup() for runtime PM (Rafael J. Wysocki)

  - restore the status of PCI devices across hibernation (Chen Yu)

  - keep parent resources that start at 0x0 (Ard Biesheuvel)

  - enable ECRC only if device supports it (Bjorn Helgaas)

  - restore PRI and PASID state after Function-Level Reset (CQ Tang)

  - skip DPC event if device is not present (Keith Busch)

  - check domain when matching SMBIOS info (Sujith Pandel)

  - mark Intel XXV710 NIC INTx masking as broken (Alex Williamson)

  - avoid AMD SB7xx EHCI USB wakeup defect (Kai-Heng Feng)

  - work around long-standing Macbook Pro poweroff issue (Bjorn Helgaas)

  - add Switchtec "running" status flag (Logan Gunthorpe)

  - fix dra7xx incorrect RW1C IRQ register usage (Arvind Yadav)

  - modify xilinx-nwl IRQ chip for legacy interrupts (Bharat Kumar
    Gogada)

  - move VMD SRCU cleanup after bus, child device removal (Jon Derrick)

  - add Faraday clock handling (Linus Walleij)

  - configure Rockchip MPS and reorganize (Shawn Lin)

  - limit Qualcomm TLP size to 2K (hardware issue) (Srinivas Kandagatla)

  - support Tegra MSI 64-bit addressing (Thierry Reding)

  - use Rockchip normal (not privileged) register bank (Shawn Lin)

  - add HiSilicon Kirin SoC PCIe controller driver (Xiaowei Song)

  - add Sigma Designs Tango SMP8759 PCIe controller driver (Marc
    Gonzalez)

  - add MediaTek PCIe host controller support (Ryder Lee)

  - add Qualcomm IPQ4019 support (John Crispin)

  - add HyperV vPCI protocol v1.2 support (Jork Loeser)

  - add i.MX6 regulator support (Quentin Schulz)

* tag 'pci-v4.13-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (113 commits)
  PCI: tango: Add Sigma Designs Tango SMP8759 PCIe host bridge support
  PCI: Add DT binding for Sigma Designs Tango PCIe controller
  PCI: rockchip: Use normal register bank for config accessors
  dt-bindings: PCI: Add documentation for MediaTek PCIe
  PCI: Remove __pci_dev_reset() and pci_dev_reset()
  PCI: Split ->reset_notify() method into ->reset_prepare() and ->reset_done()
  PCI: xilinx: Make of_device_ids const
  PCI: xilinx-nwl: Modify IRQ chip for legacy interrupts
  PCI: vmd: Move SRCU cleanup after bus, child device removal
  PCI: vmd: Correct comment: VMD domains start at 0x10000, not 0x1000
  PCI: versatile: Add local struct device pointers
  PCI: tegra: Do not allocate MSI target memory
  PCI: tegra: Support MSI 64-bit addressing
  PCI: rockchip: Use local struct device pointer consistently
  PCI: rockchip: Check for clk_prepare_enable() errors during resume
  MAINTAINERS: Remove Wenrui Li as Rockchip PCIe driver maintainer
  PCI: rockchip: Configure RC's MPS setting
  PCI: rockchip: Reconfigure configuration space header type
  PCI: rockchip: Split out rockchip_pcie_cfg_configuration_accesses()
  PCI: rockchip: Move configuration accesses into rockchip_pcie_cfg_atu()
  ...
2017-07-08 15:51:57 -07:00
Christoph Hellwig 9a0ef98e18 genirq/affinity: Assign vectors to all present CPUs
Currently the irq vector spread algorithm is restricted to online CPUs,
which ties the IRQ mapping to the currently online devices and doesn't deal
nicely with the fact that CPUs could come and go rapidly due to e.g. power
management.

Instead assign vectors to all present CPUs to avoid this churn.

Build a map of all possible CPUs for a given node, as the architectures
only provide a map of all onlines CPUs. Do this dynamically on each call
for the vector assingments, which is a bit suboptimal and could be
optimized in the future by provinding a mapping from the arch code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linux-nvme@lists.infradead.org
Cc: Keith Busch <keith.busch@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170603140403.27379-5-hch@lst.de
2017-06-22 18:21:26 +02:00
Michael Hernandez 6f9a22bc57 PCI/MSI: Ignore affinity if pre/post vector count is more than min_vecs
min_vecs is the minimum amount of vectors needed to operate in MSI-X mode
which may just include the vectors that don't need affinity.

Disabling affinity settings causes the qla2xxx driver scsi_add_host() to fail
when blk_mq is enabled as the blk_mq_pci_map_queues() expects affinity masks
on each vector.

Fixes: dfef358bd1 ("PCI/MSI: Don't apply affinity if there aren't enough vectors left")
Signed-off-by: Michael Hernandez <michael.hernandez@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org	# v4.10+
2017-05-22 15:06:05 -05:00
Keith Busch b72f8051f3 genirq/affinity: Fix calculating vectors to assign
The vectors_per_node is calculated from the remaining available vectors.
The current vector starts after pre_vectors, so we need to subtract that
from the current to properly account for the number of remaining vectors
to assign.

Fixes: 3412386b53 ("irq/affinity: Fix extra vecs calculation")
Reported-by: Andrei Vagin <avagin@virtuozzo.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Link: http://lkml.kernel.org/r/1492645870-13019-1-git-send-email-keith.busch@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-20 16:03:09 +02:00
Keith Busch 3412386b53 irq/affinity: Fix extra vecs calculation
This fixes a math error calculating the extra_vecs. The error assumed
only 1 cpu per vector, but the value needs to account for the actual
number of cpus per vector in order to get the correct remainder for
extra CPU assignment.

Fixes: 7bf8222b9b ("irq/affinity: Fix CPU spread for unbalanced nodes")
Reported-by: Xiaolong Ye <xiaolong.ye@intel.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Link: http://lkml.kernel.org/r/1492104492-19943-1-git-send-email-keith.busch@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-13 23:41:00 +02:00
Keith Busch 7bf8222b9b irq/affinity: Fix CPU spread for unbalanced nodes
The irq_create_affinity_masks routine is responsible for assigning a
number of interrupt vectors to CPUs. The optimal assignemnet will spread
requested vectors to all CPUs, with the fewest CPUs sharing a vector.

The algorithm may fail to assign some vectors to any CPUs if a node's
CPU count is lower than the average number of vectors per node. These
vectors are unusable and create an un-optimal spread.

Recalculate the number of vectors to assign at each node iteration by using
the remaining number of vectors and nodes to be assigned, not exceeding the
number of CPUs in that node. This will guarantee that every CPU is assigned
at least one vector.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: linux-nvme@lists.infradead.org
Link: http://lkml.kernel.org/r/1491247553-7603-1-git-send-email-keith.busch@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-04 11:57:28 +02:00
Guilherme G. Piccoli c0af524372 genirq/affinity: Fix node generation from cpumask
Commit 34c3d9819f ("genirq/affinity: Provide smarter irq spreading
infrastructure") introduced a better IRQ spreading mechanism, taking
account of the available NUMA nodes in the machine.

Problem is that the algorithm of retrieving the nodemask iterates
"linearly" based on the number of online nodes - some architectures
present non-linear node distribution among the nodemask, like PowerPC.
If this is the case, the algorithm lead to a wrong node count number
and therefore to a bad/incomplete IRQ affinity distribution.

For example, this problem were found in a machine with 128 CPUs and two
nodes, namely nodes 0 and 8 (instead of 0 and 1, if it was linearly
distributed). This led to a wrong affinity distribution which then led to
a bad mq allocation for nvme driver.

Finally, we take the opportunity to fix a comment regarding the affinity
distribution when we have _more_ nodes than vectors.

Fixes: 34c3d9819f ("genirq/affinity: Provide smarter irq spreading infrastructure")
Reported-by: Gabriel Krisman Bertazi <gabriel@krisman.be>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Gabriel Krisman Bertazi <gabriel@krisman.be>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Cc: linux-pci@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: hch@lst.de
Link: http://lkml.kernel.org/r/1481738472-2671-1-git-send-email-gpiccoli@linux.vnet.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-15 12:32:35 +01:00
Thomas Gleixner b6e5d5b947 genirq/affinity: Use default affinity mask for reserved vectors
The reserved vectors at the beginning and the end of the vector space get
cpu_possible_mask assigned as their affinity mask.

All other non-auto affine interrupts get the default irq affinity mask
assigned. Using cpu_possible_mask breaks that rule.

Treat them like any other interrupt and use irq_default_affinity as target
mask.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Hellwig <hch@lst.de>
2016-11-16 18:44:01 +01:00
Christoph Hellwig bfe1307738 genirq/affinity: Take reserved vectors into account when spreading irqs
The recent addition of reserved vectors at the beginning or the end of the
vector space did not take the reserved vectors at the beginning into
account for the various loop exit conditions. As a consequence the last
vectors of the spread area are not included into the spread algorithm and
are treated like the reserved vectors at the end of the vector space and
get the default affinity mask assigned.

Sum up the affinity vectors and the reserved vectors at the beginning and
use the sum as exit condition.

[ tglx: Fixed all conditions instead of only one and massaged changelog ]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/1479201178-29604-2-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 18:44:01 +01:00
Christoph Hellwig 67c93c218d genirq/affinity: Handle pre/post vectors in irq_create_affinity_masks()
Only calculate the affinity for the main I/O vectors, and skip the
pre or post vectors specified by struct irq_affinity.

Also remove the irq_affinity cpumask argument that has never been used.
If we ever need it in the future we can pass it through struct
irq_affinity.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Link: http://lkml.kernel.org/r/1478654107-7384-4-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-09 08:25:09 +01:00
Christoph Hellwig 212bd84622 genirq/affinity: Handle pre/post vectors in irq_calc_affinity_vectors()
Only calculate the affinity for the main I/O vectors, and skip the pre or
post vectors specified by struct irq_affinity.

Also remove the irq_affinity cpumask argument that has never been used.  If
we ever need it in the future we can pass it through struct irq_affinity.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Acked-by: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Link: http://lkml.kernel.org/r/1478654107-7384-3-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-09 08:25:08 +01:00
Thomas Gleixner 44082fd670 genirq/affinity: Remove old irq spread infrastructure
No more users.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: axboe@fb.com
Cc: keith.busch@intel.com
Cc: agordeev@redhat.com
Cc: linux-block@vger.kernel.org
Link: http://lkml.kernel.org/r/1473862739-15032-5-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-14 22:11:09 +02:00
Thomas Gleixner 34c3d9819f genirq/affinity: Provide smarter irq spreading infrastructure
The current irq spreading infrastructure is just looking at a cpumask and
tries to spread the interrupts over the mask. Thats suboptimal as it does
not take numa nodes into account.

Change the logic so the interrupts are spread across numa nodes and inside
the nodes. If there are more cpus than vectors per node, then we set the
affinity to several cpus. If HT siblings are available we take that into
account and try to set all siblings to a single vector.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: axboe@fb.com
Cc: keith.busch@intel.com
Cc: agordeev@redhat.com
Cc: linux-block@vger.kernel.org
Link: http://lkml.kernel.org/r/1473862739-15032-3-git-send-email-hch@lst.de
2016-09-14 22:11:08 +02:00
Christoph Hellwig 3ee0ce2a54 genirq/affinity: Use get/put_online_cpus around cpumask operations
Without locking out CPU mask operations we might end up with an inconsistent
view of the cpumask in the function.

Fixes: 5e385a6ef31f: "genirq: Add a helper to spread an affinity mask for MSI/MSI-X vectors"
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/1470924405-25728-1-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-08-22 11:22:44 +02:00
Christoph Hellwig 5e385a6ef3 genirq: Add a helper to spread an affinity mask for MSI/MSI-X vectors
This is lifted from the blk-mq code and adopted to use the affinity mask
concept just introduced in the irq handling code.  It tries to keep the
algorithm the same as the one current used by blk-mq, but improvements
like assining vectors on a per-node basis instead of just per sibling
are possible with this simple move and refactoring.

Signed-off-by: Christoph Hellwig <hch@lst.de>
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/1467621574-8277-7-git-send-email-hch@lst.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-07-04 12:25:14 +02:00