linux/arch/mips
Thomas Gleixner 01f8fa4f01 genirq: Allow forcing cpu affinity of interrupts
The current implementation of irq_set_affinity() refuses rightfully to
route an interrupt to an offline cpu.

But there is a special case, where this is actually desired. Some of
the ARM SoCs have per cpu timers which require setting the affinity
during cpu startup where the cpu is not yet in the online mask.

If we can't do that, then the local timer interrupt for the about to
become online cpu is routed to some random online cpu.

The developers of the affected machines tried to work around that
issue, but that results in a massive mess in that timer code.

We have a yet unused argument in the set_affinity callbacks of the irq
chips, which I added back then for a similar reason. It was never
required so it got not used. But I'm happy that I never removed it.

That allows us to implement a sane handling of the above scenario. So
the affected SoC drivers can add the required force handling to their
interrupt chip, switch the timer code to irq_force_affinity() and
things just work.

This does not affect any existing user of irq_set_affinity().

Tagged for stable to allow a simple fix of the affected SoC clock
event drivers.

Reported-and-tested-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Tomasz Figa <t.figa@samsung.com>,
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>,
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: linux-arm-kernel@lists.infradead.org,
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20140416143315.717251504@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-04-17 23:36:27 +02:00
..
alchemy Merge branch '3.14-fixes' into mips-for-linux-next 2014-03-31 18:17:33 +02:00
ar7 MIPS: Restore init.h usage to arch/mips/ar7/time.c 2014-03-26 23:09:23 +01:00
ath79 usb: host: remove selects of USB_ARCH_HAS_?HCI 2014-02-18 12:36:38 -08:00
bcm47xx Merge branch '3.14-fixes' into mips-for-linux-next 2014-03-31 18:17:33 +02:00
bcm63xx MIPS: Use current_cpu_type() instead of c->cputype 2014-03-31 18:17:12 +02:00
boot mips: delete non-required instances of include <linux/init.h> 2014-01-24 22:39:56 +01:00
cavium-octeon genirq: Allow forcing cpu affinity of interrupts 2014-04-17 23:36:27 +02:00
cobalt MIPS: Cobalt: Move to 8250/16550 serial early printk driver 2013-10-29 21:24:38 +01:00
configs MIPS: Loongson: Add a Loongson-3 default config file 2014-03-31 18:17:12 +02:00
dec DEC: Whitespace cleanup 2013-10-29 21:24:44 +01:00
emma MIPS: Remove panic_timeout settings 2013-11-26 12:12:27 +01:00
fw mips: delete non-required instances of include <linux/init.h> 2014-01-24 22:39:56 +01:00
include Merge git://git.infradead.org/users/eparis/audit 2014-04-12 12:38:53 -07:00
jazz
jz4740 mips: delete non-required instances of include <linux/init.h> 2014-01-24 22:39:56 +01:00
kernel Merge git://git.infradead.org/users/eparis/audit 2014-04-12 12:38:53 -07:00
kvm MIPS: KVM: Remove dead code in CP0 emulation 2014-03-19 17:01:50 +01:00
lantiq mips: delete non-required instances of include <linux/init.h> 2014-01-24 22:39:56 +01:00
lasat MIPS: Lasat: Replace del_timer by del_timer_sync 2014-03-31 18:17:12 +02:00
lib MIPS: lib: csum_partial: Add EVA support 2014-03-26 23:09:17 +01:00
loongson cpufreq: create another field .flags in cpufreq_frequency_table 2014-04-07 14:43:50 +02:00
loongson1 MIPS: Idle: Consolidate all declarations in <asm/idle.h>. 2013-05-22 01:34:27 +02:00
math-emu Merge branch '3.14-fixes' into mips-for-linux-next 2014-03-31 18:17:33 +02:00
mm MIPS: Loongson: Add basic Loongson-3 CPU support 2014-03-31 18:17:12 +02:00
mti-malta Merge branch '3.14-fixes' into mips-for-linux-next 2014-03-31 18:17:33 +02:00
mti-sead3 MIPS: SEAD3: Don't use module_init in non-modular sead3-mtd.c code 2014-03-31 18:17:12 +02:00
netlogic Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2014-01-30 17:20:32 -08:00
oprofile MIPS: Add support for the M5150 processor 2014-03-26 23:09:22 +01:00
pci Merge branch '3.14-fixes' into mips-for-linux-next 2014-03-31 18:17:33 +02:00
pmcs-msp71xx MIPS: Fix gigaton of warning building with microMIPS. 2014-03-31 18:17:12 +02:00
pnx833x MIPS: PNX833x: PNX8335_PCI_ETHERNET_INT depends on CONFIG_SOC_PNX8335 2013-08-05 13:34:22 +02:00
power MIPS: Hibernate: Flush TLB entries in swsusp_arch_resume() 2014-03-31 10:16:53 +02:00
ralink usb: host: remove selects of USB_ARCH_HAS_?HCI 2014-02-18 12:36:38 -08:00
rb532
sgi-ip22 mips: Use the core irq stats function 2014-03-04 17:37:53 +01:00
sgi-ip27 mips: delete non-required instances of include <linux/init.h> 2014-01-24 22:39:56 +01:00
sgi-ip32
sibyte mips: Validate online cpus in irq_set_affinity() callbacks 2014-03-12 13:07:40 +01:00
sni MIPS: Cleanup CP0 PRId and CP1 FPIR register access masks 2013-09-18 20:25:19 +02:00
txx9 MIPS: TXx9: Fix build error if CONFIG_TOSHIBA_JMR3927 is not selected 2013-09-03 15:30:50 +02:00
vr41xx MIPS: Idle: Consolidate all declarations in <asm/idle.h>. 2013-05-22 01:34:27 +02:00
Kbuild KVM/MIPS32: Infrastructure/build files. 2013-05-08 03:55:34 +02:00
Kbuild.platforms MIPS: PowerTV: Remove support code. 2013-10-29 21:25:17 +01:00
Kconfig Kconfig: rename HAS_IOPORT to HAS_IOPORT_MAP 2014-04-07 16:36:11 -07:00
Kconfig.debug MIPS: Fix build error due to multiple prom_putchar() definitions. 2014-03-31 10:16:52 +02:00
Makefile MIPS: Add MSA register definitions & access 2014-03-26 23:09:10 +01:00