kernel/linux.git/include/linux/interrupt.h, branch linux-4.12.y

PCI/MSI: Ignore affinity if pre/post vector count is more than min_vecs

2017-07-27T22:10:09+00:00

commit 6f9a22bc5775d231ab8fbe2c2f3c88e45e3e7c28 upstream. 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: dfef358bd1be ("PCI/MSI: Don't apply affinity if there aren't enough vectors left") Signed-off-by: Michael Hernandez Signed-off-by: Himanshu Madhani Signed-off-by: Bjorn Helgaas Reviewed-by: Christoph Hellwig Signed-off-by: Greg Kroah-Hartman

genirq: Return the IRQ name from free_irq()

2017-04-18T18:40:00+00:00

This allows callers to get back at them instead of having to store it in another variable. Signed-off-by: Christoph Hellwig Signed-off-by: Bjorn Helgaas Reviewed-by: Thomas Gleixner

genirq/affinity: Handle pre/post vectors in irq_create_affinity_masks()

2016-11-09T07:25:09+00:00

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 Reviewed-by: Hannes Reinecke Acked-by: Bjorn Helgaas Acked-by: Jens Axboe 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

genirq/affinity: Handle pre/post vectors in irq_calc_affinity_vectors()

2016-11-09T07:25:08+00:00

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 Reviewed-by: Hannes Reinecke Acked-by: Jens Axboe 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

genirq/affinity: Introduce struct irq_affinity

2016-11-09T07:25:08+00:00

Some drivers (various network and RDMA adapter for example) have a MSI-X vector layout where most of the vectors are used for I/O queues and should have CPU affinity assigned to them, but some (usually 1 but sometimes more) at the beginning or end are used for low-performance admin or configuration work and should not have any explicit affinity assigned to them. Add a new irq_affinity structure, which will be passed through a variant of pci_irq_alloc_vectors that allows to specify these requirements (and is extensible to any future quirks in that area) so that the core IRQ affinity algorithm can take this quirks into account. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Reviewed-by: Hannes Reinecke Acked-by: Jens Axboe Cc: linux-block@vger.kernel.org Cc: linux-pci@vger.kernel.org Link: http://lkml.kernel.org/r/1478654107-7384-2-git-send-email-hch@lst.de Signed-off-by: Thomas Gleixner

genirq/affinity: Remove old irq spread infrastructure

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

No more users. Signed-off-by: Thomas Gleixner Cc: Christoph Hellwig 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

genirq/affinity: Provide smarter irq spreading infrastructure

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

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 Cc: Christoph Hellwig 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

genirq: Add a helper to spread an affinity mask for MSI/MSI-X vectors

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

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 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

arch, ftrace: for KASAN put hard/soft IRQ entries into separate sections

2016-03-25T23:37:42+00:00

KASAN needs to know whether the allocation happens in an IRQ handler. This lets us strip everything below the IRQ entry point to reduce the number of unique stack traces needed to be stored. Move the definition of __irq_entry to so that the users don't need to pull in . Also introduce the __softirq_entry macro which is similar to __irq_entry, but puts the corresponding functions to the .softirqentry.text section. Signed-off-by: Alexander Potapenko Acked-by: Steven Rostedt Cc: Christoph Lameter Cc: Pekka Enberg Cc: David Rientjes Cc: Joonsoo Kim Cc: Andrey Konovalov Cc: Dmitry Vyukov Cc: Andrey Ryabinin Cc: Konstantin Serebryany Cc: Dmitry Chernenkov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

x86/ACPI/PCI: Recognize that Interrupt Line 255 means "not connected"

2016-03-09T00:23:35+00:00

Per the x86-specific footnote to PCI spec r3.0, sec 6.2.4, the value 255 in the Interrupt Line register means "unknown" or "no connection." Previously, when we couldn't derive an IRQ from the _PRT, we fell back to using the value from Interrupt Line as an IRQ. It's questionable whether we should do that at all, but the spec clearly suggests we shouldn't do it for the value 255 on x86. Calling request_irq() with IRQ 255 may succeed, but the driver won't receive any interrupts. Or, if IRQ 255 is shared with another device, it may succeed, and the driver's ISR will be called at random times when the *other* device interrupts. Or it may fail if another device is using IRQ 255 with incompatible flags. What we *want* is for request_irq() to fail predictably so the driver can fall back to polling. On x86, assume 255 in the Interrupt Line means the INTx line is not connected. In that case, set dev->irq to IRQ_NOTCONNECTED so request_irq() will fail gracefully with -ENOTCONN. We found this problem on a system where Secure Boot firmware assigned Interrupt Line 255 to an i801_smbus device and another device was already using MSI-X IRQ 255. This was in v3.10, where i801_probe() fails if request_irq() fails: i801_smbus 0000:00:1f.3: enabling device (0140 -> 0143) i801_smbus 0000:00:1f.3: can't derive routing for PCI INT C i801_smbus 0000:00:1f.3: PCI INT C: no GSI genirq: Flags mismatch irq 255. 00000080 (i801_smbus) vs. 00000000 (megasa) CPU: 0 PID: 2487 Comm: kworker/0:1 Not tainted 3.10.0-229.el7.x86_64 #1 Hardware name: FUJITSU PRIMEQUEST 2800E2/D3736, BIOS PRIMEQUEST 2000 Serie5 Call Trace: dump_stack+0x19/0x1b __setup_irq+0x54a/0x570 request_threaded_irq+0xcc/0x170 i801_probe+0x32f/0x508 [i2c_i801] local_pci_probe+0x45/0xa0 i801_smbus 0000:00:1f.3: Failed to allocate irq 255: -16 i801_smbus: probe of 0000:00:1f.3 failed with error -16 After aeb8a3d16ae0 ("i2c: i801: Check if interrupts are disabled"), i801_probe() will fall back to polling if request_irq() fails. But we still need this patch because request_irq() may succeed or fail depending on other devices in the system. If request_irq() fails, i801_smbus will work by falling back to polling, but if it succeeds, i801_smbus won't work because it expects interrupts that it may not receive. Signed-off-by: Chen Fan Acked-by: Thomas Gleixner Acked-by: Bjorn Helgaas Signed-off-by: Rafael J. Wysocki