linux/kernel
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
..
debug mm: per-thread vma caching 2014-04-07 16:35:53 -07:00
events Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm 2014-04-05 13:20:43 -07:00
gcov gcov: reuse kbasename helper 2013-11-13 12:09:34 +09:00
irq genirq: Allow forcing cpu affinity of interrupts 2014-04-17 23:36:27 +02:00
locking Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-04-16 16:35:18 -07:00
power kernel: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:36:11 -07:00
printk printk: fix one circular lockdep warning about console_lock 2014-04-03 16:21:08 -07:00
rcu Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-03-31 11:21:19 -07:00
sched Merge branch 'akpm' (incoming from Andrew) 2014-04-07 16:38:06 -07:00
time kernel: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:36:11 -07:00
trace Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-04-12 14:49:50 -07:00
.gitignore Ignore generated file kernel/x509_certificate_list 2013-12-10 18:21:34 +00:00
Kconfig.freezer
Kconfig.hz kernel: remove CONFIG_USE_GENERIC_SMP_HELPERS 2013-11-15 09:32:22 +09:00
Kconfig.locks locking: Fix copy/paste errors of "ARCH_INLINE_*_UNLOCK_BH" 2013-05-28 08:50:00 +02:00
Kconfig.preempt
Makefile Merge branch 'x86-asmlinkage-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-03-31 14:13:25 -07:00
acct.c fs: Fix hang with BSD accounting on frozen filesystem 2013-05-04 14:57:58 -04:00
async.c
audit.c Merge git://git.infradead.org/users/eparis/audit 2014-04-12 12:38:53 -07:00
audit.h audit: Use struct net not pid_t to remember the network namespce to reply in 2014-03-20 10:10:53 -04:00
audit_tree.c inotify: Fix reporting of cookies for inotify events 2014-02-18 11:17:17 +01:00
audit_watch.c inotify: Fix reporting of cookies for inotify events 2014-02-18 11:17:17 +01:00
auditfilter.c Merge git://git.infradead.org/users/eparis/audit 2014-04-12 12:38:53 -07:00
auditsc.c Merge git://git.infradead.org/users/eparis/audit 2014-04-12 12:38:53 -07:00
backtracetest.c
bounds.c mm: do not allocate page->ptl dynamically, if spinlock_t fits to long 2013-12-20 12:25:45 -08:00
capability.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2014-04-03 09:26:18 -07:00
cgroup.c cgroup: newly created dirs and files should be owned by the creator 2014-04-07 16:44:47 -04:00
cgroup_freezer.c cgroup: drop const from @buffer of cftype->write_string() 2014-03-19 10:23:54 -04:00
compat.c Merge branch 'x86-x32-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-04-02 12:51:41 -07:00
configs.c proc: Supply PDE attribute setting accessor functions 2013-05-01 17:29:18 -04:00
context_tracking.c context_tracking: Wrap static key check into more intuitive function name 2013-12-02 20:43:14 +01:00
cpu.c CPU hotplug: Provide lockless versions of callback registration functions 2014-03-20 13:43:40 +01:00
cpu_pm.c
cpuset.c Merge branch 'akpm' (incoming from Andrew) 2014-04-03 16:22:16 -07:00
crash_dump.c
cred.c
delayacct.c kernel/delayacct.c: remove redundant checking in __delayacct_add_tsk() 2013-11-13 12:09:12 +09:00
dma.c
elfcore.c switch elf_core_write_extra_phdrs() to dump_emit() 2013-11-09 00:16:23 -05:00
exec_domain.c
exit.c wait: WSTOPPED|WCONTINUED doesn't work if a zombie leader is traced by another process 2014-04-07 16:36:06 -07:00
extable.c asmlinkage: Make main_extable_sort_needed visible 2014-02-13 18:13:22 -08:00
fork.c kernel: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:36:11 -07:00
freezer.c libata, freezer: avoid block device removal while system is frozen 2013-12-19 13:50:32 -05:00
futex.c futex: update documentation for ordering guarantees 2014-04-12 17:57:51 -07:00
futex_compat.c compat: Get rid of (get|put)_compat_time(val|spec) 2014-02-02 14:09:12 -08:00
groups.c kernel/groups.c: remove return value of set_groups 2014-04-03 16:21:05 -07:00
hrtimer.c timer: Remove code redundancy while calling get_nohz_timer_target() 2014-03-20 12:35:46 +01:00
hung_task.c kernel: audit/fix non-modular users of module_init in core code 2014-04-03 16:21:07 -07:00
irq_work.c perf/x86: Warn to early_printk() in case irq_work is too slow 2014-02-21 21:49:07 +01:00
itimer.c
jump_label.c static_key: WARN on usage before jump_label_init was called 2013-10-19 19:45:35 -04:00
kallsyms.c kernel: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:36:11 -07:00
kcmp.c
kexec.c kernel: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:36:11 -07:00
kmod.c execve: use 'struct filename *' for executable name passing 2014-02-05 12:54:53 -08:00
kprobes.c kprobes: use KSYM_NAME_LEN to size identifier buffers 2013-11-13 12:09:26 +09:00
ksysfs.c kernel: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:36:11 -07:00
kthread.c kthread: ensure locality of task_struct allocations 2014-04-03 16:20:49 -07:00
latencytop.c
module-internal.h KEYS: Separate the kernel signature checking keyring from module signing 2013-09-25 17:17:01 +01:00
module.c modules: use raw_cpu_write for initialization of per cpu refcount. 2014-04-07 16:36:14 -07:00
module_signing.c keys: change asymmetric keys to use common hash definitions 2013-10-25 17:15:18 -04:00
notifier.c notifier: Substitute rcu_access_pointer() for rcu_dereference_raw() 2014-02-26 06:35:13 -08:00
nsproxy.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2013-09-07 14:35:32 -07:00
padata.c padata: Fix wrong usage of rcu_dereference() 2013-12-05 21:28:42 +08:00
panic.c kernel/panic.c: display reason at end + pr_emerg 2014-04-07 16:36:08 -07:00
params.c params: improve standard definitions 2013-12-04 14:09:46 +10:30
pid.c pidns: fix free_pid() to handle the first fork failure 2013-09-30 14:31:03 -07:00
pid_namespace.c pid_namespace: pidns_get() should check task_active_pid_ns() != NULL 2014-04-02 16:20:21 -07:00
posix-cpu-timers.c posix-timers: Convert abuses of BUG_ON to WARN_ON 2013-12-09 16:56:29 +01:00
posix-timers.c
profile.c CPU hotplug notifiers registration fixes for 3.15-rc1 2014-04-07 14:55:46 -07:00
ptrace.c kernel/compat: convert to COMPAT_SYSCALL_DEFINE 2014-03-06 15:35:10 +01:00
range.c range: Do not add new blank slot with add_range_with_merge 2013-06-18 11:32:10 -05:00
reboot.c kexec: migrate to reboot cpu 2013-12-18 19:04:50 -08:00
relay.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-04-12 14:49:50 -07:00
res_counter.c res_counter: remove interface for locked charging and uncharging 2014-04-07 16:35:54 -07:00
resource.c kernel/resource.c: make reallocate_resource() static 2014-04-03 16:21:07 -07:00
seccomp.c seccomp: fix populating a0-a5 syscall args in 32-bit x86 BPF 2014-04-14 16:26:47 -04:00
signal.c kernel: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:36:11 -07:00
smp.c smp: Rename __smp_call_function_single() to smp_call_function_single_async() 2014-02-24 14:47:15 -08:00
smpboot.c kernel: delete __cpuinit usage from all core kernel files 2013-07-14 19:36:59 -04:00
smpboot.h
softirq.c softirq: Add linux/irq.h to make it compile again 2014-03-19 11:28:14 +01:00
stacktrace.c
stop_machine.c stop_machine: Fix^2 race between stop_two_cpus() and stop_cpus() 2014-03-11 11:33:47 +01:00
sys.c mm, thp: add VM_INIT_DEF_MASK and PRCTL_THP_DISABLE 2014-04-07 16:35:52 -07:00
sys_ni.c fs, kernel: permit disabling the uselib syscall 2014-04-03 16:21:05 -07:00
sysctl.c hung_task: check the value of "sysctl_hung_task_timeout_sec" 2014-04-07 16:36:07 -07:00
sysctl_binary.c kernel/sysctl_binary.c: use scnprintf() instead of snprintf() 2013-11-13 12:09:33 +09:00
system_certificates.S KEYS: correct alignment of system_certificate_list content in assembly file 2013-12-10 18:25:28 +00:00
system_keyring.c KEYS: correct alignment of system_certificate_list content in assembly file 2013-12-10 18:25:28 +00:00
task_work.c task_work: documentation 2013-09-11 15:58:27 -07:00
taskstats.c genetlink: only pass array to genl_register_family_with_ops() 2013-11-19 16:39:05 -05:00
test_kprobes.c kernel/: rename random32() to prandom_u32() 2013-04-29 18:28:42 -07:00
time.c sched: Rename sched.c as sched/core.c in comments and Documentation 2013-06-19 12:58:42 +02:00
timeconst.bc
timer.c Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-04-01 11:00:07 -07:00
torture.c rcutorture: Gracefully handle NULL cleanup hooks 2014-02-23 09:04:39 -08:00
tracepoint.c This includes the final patch to clean up and fix the issue with the 2014-04-12 13:06:10 -07:00
tsacct.c
uid16.c userns: Kill nsown_capable it makes the wrong thing easy 2013-08-30 23:44:11 -07:00
up.c smp: Rename __smp_call_function_single() to smp_call_function_single_async() 2014-02-24 14:47:15 -08:00
user-return-notifier.c
user.c kernel: audit/fix non-modular users of module_init in core code 2014-04-03 16:21:07 -07:00
user_namespace.c user namespace: fix incorrect memory barriers 2014-04-14 16:03:02 -07:00
utsname.c userns: Kill nsown_capable it makes the wrong thing easy 2013-08-30 23:44:11 -07:00
utsname_sysctl.c
watchdog.c kernel/watchdog.c: touch_nmi_watchdog should only touch local cpu not every one 2014-04-03 16:20:58 -07:00
workqueue.c Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-04-01 11:00:07 -07:00
workqueue_internal.h sched: Rename sched.c as sched/core.c in comments and Documentation 2013-06-19 12:58:42 +02:00