linux-sg2042/drivers
Anup Patel cc9f04f9a8 irqchip/sifive-plic: Implement irq_set_affinity() for SMP host
Currently on SMP host, all CPUs take external interrupts routed via
PLIC. All CPUs will try to claim a given external interrupt but only
one of them will succeed while other CPUs would simply resume whatever
they were doing before. This means if we have N CPUs then for every
external interrupt N-1 CPUs will always fail to claim it and waste
their CPU time.

Instead of above, external interrupts should be taken by only one CPU
and we should have provision to explicitly specify IRQ affinity from
kernel-space or user-space.

This patch provides irq_set_affinity() implementation for PLIC driver.
It also updates irq_enable() such that PLIC interrupts are only enabled
for one of CPUs specified in IRQ affinity mask.

With this patch in-place, we can change IRQ affinity at any-time from
user-space using procfs.

Example:

/ # cat /proc/interrupts
           CPU0       CPU1       CPU2       CPU3
  8:         44          0          0          0  SiFive PLIC   8  virtio0
 10:         48          0          0          0  SiFive PLIC  10  ttyS0
IPI0:        55        663         58        363  Rescheduling interrupts
IPI1:         0          1          3         16  Function call interrupts
/ #
/ #
/ # echo 4 > /proc/irq/10/smp_affinity
/ #
/ # cat /proc/interrupts
           CPU0       CPU1       CPU2       CPU3
  8:         45          0          0          0  SiFive PLIC   8  virtio0
 10:        160          0         17          0  SiFive PLIC  10  ttyS0
IPI0:        68        693         77        410  Rescheduling interrupts
IPI1:         0          2          3         16  Function call interrupts

Signed-off-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-02-21 10:32:21 +00:00
..
accessibility
acpi libnvdimm v5.0-rc3 2019-01-20 10:24:30 +12:00
amba
android binder: implement binderfs 2018-12-19 09:40:13 +01:00
ata ata: pata_acpi: Make PCI dependency explicit 2019-01-15 23:16:34 +01:00
atm atm: he: fix sign-extension overflow on large shift 2019-01-17 11:27:00 -08:00
auxdisplay auxdisplay: charlcd: fix x/y command parsing 2018-12-21 21:27:21 +01:00
base regmap: Fixes for v5.0 2019-01-19 07:17:19 +12:00
bcma
block for-linus-20190118 2019-01-20 09:12:50 +12:00
bluetooth Bluetooth: hci_bcm: Handle specific unknown packets after firmware loading 2018-12-19 13:43:42 +01:00
bus ARM: SoC driver updates 2018-12-31 17:32:35 -08:00
cdrom gdrom: fix a memory leak bug 2018-12-29 08:20:44 -07:00
char Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
clk Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2019-01-02 18:56:59 -08:00
clocksource arch/csky patches for 4.21-rc1 2019-01-05 09:50:07 -08:00
connector
cpufreq Merge branches 'pm-cpuidle', 'pm-cpufreq' and 'pm-sleep' 2019-01-11 10:09:51 +01:00
cpuidle powerpc updates for 4.21 2018-12-27 10:43:24 -08:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-01-19 05:48:43 +12:00
dax mm, devm_memremap_pages: fix shutdown handling 2018-12-28 12:11:47 -08:00
dca
devfreq
dio
dma cross-tree: phase out dma_zalloc_coherent() 2019-01-08 07:58:37 -05:00
dma-buf drivers/dma-buf/udmabuf.c: convert to use vm_fault_t 2019-01-04 13:13:46 -08:00
edac EDAC, fsl_ddr: Add LS1021A to the list of supported hardware 2018-12-19 11:57:45 +01:00
eisa
extcon
firewire FireWire (IEEE 1394) subsystem patch: 2019-01-05 18:33:21 -08:00
firmware arm64 fixes for -rc1 2019-01-05 11:28:39 -08:00
fmc
fpga Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
fsi
gnss
gpio gpio: pca953x: Make symbol 'pca953x_i2c_regmap' static 2019-01-11 09:16:40 +01:00
gpu ACPI fixes for 5.0-rc3 2019-01-19 05:46:00 +12:00
hid Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid 2019-01-05 17:53:40 -08:00
hsi
hv Char/Misc driver patches for 4.21-rc1 2018-12-28 20:54:57 -08:00
hwmon hwmon: (tmp421) Correct the misspelling of the tmp442 compatible attribute in OF device ID table 2019-01-17 12:54:52 -08:00
hwspinlock hwspinlock: fix return value check in stm32_hwspinlock_probe() 2019-01-03 11:42:10 -08:00
hwtracing intel_th: msu: Fix an off-by-one in attribute store 2018-12-19 20:21:06 +01:00
i2c i2c: tegra: Fix Maximum transfer size 2019-01-11 00:15:04 +01:00
i3c i3c: master: dw-i3c-master: fix i3c_attach/reattach 2019-01-15 11:15:11 +01:00
ide for-4.21/block-20181221 2018-12-28 13:19:59 -08:00
idle
iio - New Device Support 2019-01-15 06:24:36 +12:00
infiniband First 5.0 rc pull request 2019-01-18 17:17:20 +12:00
input cross-tree: phase out dma_zalloc_coherent() 2019-01-08 07:58:37 -05:00
iommu cross-tree: phase out dma_zalloc_coherent() 2019-01-08 07:58:37 -05:00
ipack
irqchip irqchip/sifive-plic: Implement irq_set_affinity() for SMP host 2019-02-21 10:32:21 +00:00
isdn isdn: avm: Fix string plus integer warning from Clang 2019-01-19 10:01:03 -08:00
leds leds: lp5523: fix a missing check of return value of lp55xx_read 2019-01-17 22:27:39 +01:00
lightnvm lightnvm: pblk: fix use-after-free bug 2018-12-22 14:45:35 -07:00
macintosh Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
mailbox mailbox: tegra-hsp: Use device-managed registration API 2018-12-21 22:31:26 -06:00
mcb
md md: Make bio_alloc_mddev use bio_alloc_bioset 2019-01-14 06:31:56 -07:00
media media: vim2m: only cancel work if it is for right context 2019-01-16 11:13:25 -05:00
memory ARM: SoC: late updates 2019-01-05 11:30:37 -08:00
memstick MMC core: 2018-12-28 16:52:18 -08:00
message scsi: flip the default on use_clustering 2018-12-18 23:13:12 -05:00
mfd - New Device Support 2019-01-15 06:24:36 +12:00
misc virtio: don't allocate vqs when names[i] = NULL 2019-01-14 20:15:19 -05:00
mmc GPIO fixes for the v5.0 series: 2019-01-15 06:26:28 +12:00
mtd mtd: rawnand: denali: get ->setup_data_interface() working again 2019-01-18 10:27:01 +01:00
mux
net virtio_net: bulk free tx skbs 2019-01-19 16:06:52 -08:00
nfc
ntb cross-tree: phase out dma_zalloc_coherent() 2019-01-08 07:58:37 -05:00
nubus
nvdimm libnvdimm/security: Fix nvdimm_security_state() state request selection 2019-01-15 13:54:33 -08:00
nvme for-linus-20190118 2019-01-20 09:12:50 +12:00
nvmem
of OF: properties: add missing of_node_put 2019-01-16 12:49:53 -06:00
opp cpufreq: scpi/scmi: Fix freeing of dynamic OPPs 2019-01-04 12:19:40 +01:00
oprofile
parisc Kconfig file consolidation for v4.21 2018-12-29 13:40:29 -08:00
parport
pci pci-v5.0-fixes-2 2019-01-19 07:26:16 +12:00
pcmcia Included in this update: 2019-01-05 11:23:17 -08:00
perf drivers/perf: hisi: Fixup one DDRC PMU register offset 2019-01-04 10:13:27 +00:00
phy Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-01-16 05:13:36 +12:00
pinctrl Pin control bulk changes for the v4.21 kernel cycle: 2019-01-01 13:19:16 -08:00
platform platform/x86: apple-gmux: Make PCI dependency explicit 2019-01-15 23:17:16 +01:00
pnp Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
power power supply and reset changes for the v4.21 series 2018-12-28 20:22:45 -08:00
powercap
pps Kconfig updates for v4.21 2018-12-29 13:03:29 -08:00
ps3
ptp ptp: check that rsv field is zero in struct ptp_sys_offset_extended 2019-01-08 16:22:56 -05:00
pwm pwm: imx: Add ipg clock operation 2018-12-24 12:06:56 +01:00
rapidio cross-tree: phase out dma_zalloc_coherent() 2019-01-08 07:58:37 -05:00
ras treewide: surround Kconfig file paths with double quotes 2018-12-22 00:25:54 +09:00
regulator Merge remote-tracking branch 'regulator/topic/coupled' into regulator-next 2018-12-21 13:43:35 +00:00
remoteproc virtio: don't allocate vqs when names[i] = NULL 2019-01-14 20:15:19 -05:00
reset reset: uniphier-glue: Add AHCI reset control support in glue layer 2019-01-07 16:38:51 +01:00
rpmsg
rtc RTC for 4.21 2019-01-01 13:24:31 -08:00
s390 virtio: don't allocate vqs when names[i] = NULL 2019-01-14 20:15:19 -05:00
sbus Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-next 2018-12-26 10:32:18 -08:00
scsi SCSI fixes on 20190118 2019-01-20 09:15:04 +12:00
sfi
sh
siox
slimbus
sn
soc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-01-16 05:13:36 +12:00
soundwire
spi cross-tree: phase out dma_zalloc_coherent() 2019-01-08 07:58:37 -05:00
spmi
ssb
staging Staging driver fixes for 5.0-rc2 2019-01-14 05:49:35 +12:00
target scsi: tcmu: avoid cmd/qfull timers updated whenever a new cmd comes 2019-01-11 20:58:52 -05:00
tc
tee OP-TEE dynamic shm log message 2018-12-31 13:06:30 -08:00
thermal drivers: thermal: int340x_thermal: Make PCI dependency explicit 2019-01-15 23:17:40 +01:00
thunderbolt
tty tty/serial fixes for 5.0-rc2 2019-01-14 05:47:48 +12:00
uio Char/Misc driver patches for 4.21-rc1 2018-12-28 20:54:57 -08:00
usb USB fixes for 5.0-rc2 2019-01-14 05:45:28 +12:00
uwb
vfio vfio/type1: Fix unmap overflow off-by-one 2019-01-08 09:31:28 -07:00
vhost Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-01-21 12:52:31 +13:00
video fbdev fixes for v5.0-rc3: 2019-01-19 05:43:05 +12:00
virt
virtio virtio-balloon: tweak config_changed implementation 2019-01-14 20:15:20 -05:00
visorbus
vlynq
vme
w1 treewide: surround Kconfig file paths with double quotes 2018-12-22 00:25:54 +09:00
watchdog watchdog: tqmx86: Fix a couple IS_ERR() vs NULL bugs 2019-01-07 10:10:35 +01:00
xen xen: fixes for 5.0-rc3 2019-01-19 05:53:41 +12:00
zorro
Kconfig Kconfig file consolidation for v4.21 2018-12-29 13:40:29 -08:00
Makefile