Frederic Weisbecker 0a0e0829f9 nohz: Fix missing tick reprogram when interrupting an inline softirq ... The full nohz tick is reprogrammed in irq_exit() only if the exit is not in a nesting interrupt. This stands as an optimization: whether a hardirq or a softirq is interrupted, the tick is going to be reprogrammed when necessary at the end of the inner interrupt, with even potential new updates on the timer queue. When soft interrupts are interrupted, it's assumed that they are executing on the tail of an interrupt return. In that case tick_nohz_irq_exit() is called after softirq processing to take care of the tick reprogramming. But the assumption is wrong: softirqs can be processed inline as well, ie: outside of an interrupt, like in a call to local_bh_enable() or from ksoftirqd. Inline softirqs don't reprogram the tick once they are done, as opposed to interrupt tail softirq processing. So if a tick interrupts an inline softirq processing, the next timer will neither be reprogrammed from the interrupting tick's irq_exit() nor after the interrupted softirq processing. This situation may leave the tick unprogrammed while timers are armed. To fix this, simply keep reprogramming the tick even if a softirq has been interrupted. That can be optimized further, but for now correctness is more important. Note that new timers enqueued in nohz_full mode after a softirq gets interrupted will still be handled just fine through self-IPIs triggered by the timer code. Reported-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Cc: stable@vger.kernel.org # 4.14+ Link: https://lkml.kernel.org/r/1533303094-15855-1-git-send-email-frederic@kernel.org		2018-08-03 15:52:10 +02:00
..
bpf	bpf: btf: Clean up BTF_INT_BITS() in uapi btf.h	2018-07-20 10:25:48 +02:00
cgroup	docs: Fix some broken references	2018-06-15 18:10:01 -03:00
configs	kconfig: tinyconfig: remove stale stack protector fixups	2018-06-15 07:15:28 +09:00
debug	treewide: kzalloc() -> kcalloc()	2018-06-12 16:19:22 -07:00
dma	swiotlb: export swiotlb_dma_ops	2018-06-28 14:00:40 +02:00
events	perf/core: Move inline keyword at the beginning of declaration	2018-06-27 09:55:58 +02:00
gcov	gcov: remove CONFIG_GCOV_FORMAT_AUTODETECT	2018-06-08 18:56:02 +09:00
irq	genirq/debugfs: Add missing IRQCHIP_SUPPORTS_LEVEL_MSI debug	2018-06-22 14:22:00 +02:00
livepatch	livepatch: Allow to call a custom callback when freeing shadow variables	2018-04-17 13:42:48 +02:00
locking	Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2018-06-24 19:36:16 +08:00
power	fix a series of Documentation/ broken file name references	2018-06-15 18:10:01 -03:00
printk	Printk changes for 4.18	2018-06-06 16:04:55 -07:00
rcu	treewide: Use array_size() in vmalloc()	2018-06-12 16:19:22 -07:00
sched	sched/deadline: Fix switched_from_dl() warning	2018-07-15 23:47:33 +02:00
time	nohz: Fix local_timer_softirq_pending()	2018-07-31 22:08:44 +02:00
trace	tracing: Quiet gcc warning about maybe unused link variable	2018-07-25 22:33:50 -04:00
.gitignore
acct.c	kernel/acct.c: fix the acct->needcheck check in check_free_space()	2018-01-04 16:45:09 -08:00
async.c	kernel/async.c: revert "async: simplify lowest_in_progress()"	2018-02-06 18:32:44 -08:00
audit_fsnotify.c	fsnotify: add fsnotify_add_inode_mark() wrappers	2018-05-18 14:58:22 +02:00
audit_tree.c	fsnotify: add fsnotify_add_inode_mark() wrappers	2018-05-18 14:58:22 +02:00
audit_watch.c	\n	2018-06-17 05:06:18 +09:00
audit.c	audit: use inline function to get audit context	2018-05-14 17:24:18 -04:00
audit.h	audit: track the owner of the command mutex ourselves	2018-02-23 11:22:22 -05:00
auditfilter.c	audit: use existing session info function	2018-05-18 15:47:54 -04:00
auditsc.c	audit: Fix wrong task in comparison of session ID	2018-05-21 14:27:43 -04:00
backtracetest.c
bounds.c
capability.c
compat.c	Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2018-06-04 20:27:54 -07:00
configs.c
context_tracking.c
cpu_pm.c
cpu.c	cpu/hotplug: Fix unused function warning	2018-03-15 20:34:40 +01:00
crash_core.c	mm: split page_type out from _mapcount	2018-06-07 17:34:37 -07:00
crash_dump.c
cred.c
delayacct.c	delayacct: Use raw_spinlocks	2018-04-27 14:34:51 +02:00
dma.c	proc: introduce proc_create_single{,_data}	2018-05-16 07:23:35 +02:00
elfcore.c
exec_domain.c	proc: introduce proc_create_single{,_data}	2018-05-16 07:23:35 +02:00
exit.c	kernel: use kernel_wait4() instead of sys_wait4()	2018-04-02 20:14:51 +02:00
extable.c	extable: Make init_kernel_text() global	2018-02-21 16:54:06 +01:00
fail_function.c	treewide: kmalloc() -> kmalloc_array()	2018-06-12 16:19:22 -07:00
fork.c	mm: introduce vma_init()	2018-07-26 19:38:03 -07:00
freezer.c
futex_compat.c
futex.c	pids: introduce find_get_task_by_vpid() helper	2018-02-06 18:32:46 -08:00
groups.c	kernel: make groups_sort calling a responsibility group_info allocators	2017-12-14 16:00:49 -08:00
hung_task.c	kernel/hung_task.c: show all hung tasks before panic	2018-06-07 17:34:39 -07:00
iomem.c	memremap: split devm_memremap_pages() and memremap() infrastructure	2018-05-15 23:08:33 -07:00
irq_work.c	irq/work: Improve the flag definitions	2018-01-08 19:43:15 +01:00
jump_label.c	jump_label: Disable jump labels in __exit code	2018-03-20 08:57:17 +01:00
kallsyms.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk	2018-02-01 13:36:15 -08:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c	sched/core / kcov: avoid kcov_area during task switch	2018-06-15 07:55:24 +09:00
kexec_core.c	kexec: yield to scheduler when loading kimage segments	2018-06-15 07:55:24 +09:00
kexec_file.c	treewide: Use array_size() in vzalloc()	2018-06-12 16:19:22 -07:00
kexec_internal.h
kexec.c	kexec: call do_kexec_load() in compat syscall directly	2018-04-02 20:15:01 +02:00
kmod.c
kprobes.c	kprobes: Fix random address output of blacklist file	2018-04-25 10:27:56 -04:00
ksysfs.c
kthread.c	kthread, tracing: Don't expose half-written comm when creating kthreads	2018-07-26 09:59:33 -04:00
latencytop.c
Makefile	dma-mapping: move all DMA mapping code to kernel/dma	2018-06-14 08:50:37 +02:00
memremap.c	mm: fix exports that inadvertently make put_page() EXPORT_SYMBOL_GPL	2018-07-26 19:38:03 -07:00
module_signing.c
module-internal.h
module.c	Modules updates for v4.18	2018-06-16 07:36:39 +09:00
notifier.c
nsproxy.c
padata.c	padata: add SPDX identifier	2018-01-05 18:43:00 +11:00
panic.c	Kbuild: rename CC_STACKPROTECTOR[_STRONG] config variables	2018-06-14 12:21:18 +09:00
params.c	kernel/params.c: downgrade warning for unsafe parameters	2018-04-11 10:28:37 -07:00
pid_namespace.c	Merge branch 'userns-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2018-04-03 19:15:32 -07:00
pid.c	xarray: add the xa_lock to the radix_tree_root	2018-04-11 10:28:39 -07:00
profile.c
ptrace.c	pids: introduce find_get_task_by_vpid() helper	2018-02-06 18:32:46 -08:00
range.c
reboot.c
relay.c	kernel/relay.c: change return type to vm_fault_t	2018-06-15 07:55:24 +09:00
resource.c	libnvdimm for 4.18	2018-06-08 17:21:52 -07:00
rseq.c	rseq: uapi: Declare rseq_cs field as union, update includes	2018-07-10 22:18:52 +02:00
seccomp.c	audit/stable-4.18 PR 20180605	2018-06-06 16:34:00 -07:00
signal.c	signal: Remove no longer required irqsave/restore	2018-06-10 06:14:01 +02:00
smp.c
smpboot.c
smpboot.h
softirq.c	nohz: Fix missing tick reprogram when interrupting an inline softirq	2018-08-03 15:52:10 +02:00
stacktrace.c
stop_machine.c	stop_machine: Disable preemption when waking two stopper threads	2018-07-15 12:12:45 +02:00
sys_ni.c	Merge branch 'core-rseq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2018-06-10 10:17:09 -07:00
sys.c	mm: introduce arg_lock to protect arg_start|end and env_start|end in mm_struct	2018-06-07 17:34:34 -07:00
sysctl_binary.c	staging: irda: remove remaining remants of irda code removal	2018-04-16 11:26:49 +02:00
sysctl.c	treewide: kzalloc() -> kcalloc()	2018-06-12 16:19:22 -07:00
task_work.c	locking/barriers: Convert users of lockless_dereference() to READ_ONCE()	2017-12-17 13:57:15 +01:00
taskstats.c	pids: introduce find_get_task_by_vpid() helper	2018-02-06 18:32:46 -08:00
test_kprobes.c
torture.c	rcu: Rename cond_resched_rcu_qs() to cond_resched_tasks_rcu_qs()	2018-05-15 10:27:29 -07:00
tracepoint.c	tracepoints: Fix the descriptions of tracepoint_probe_register{_prio}	2018-05-28 12:49:51 -04:00
tsacct.c
ucount.c	headers: untangle kmemleak.h from mm.h	2018-04-05 21:36:27 -07:00
uid16.c	fs: add do_fchownat(), ksys_fchown() helpers and ksys_{,l}chown() wrappers	2018-04-02 20:15:59 +02:00
uid16.h	kernel: provide ksys_*() wrappers for syscalls called by kernel/uid16.c	2018-04-02 20:15:30 +02:00
umh.c	umh: fix race condition	2018-06-07 16:56:28 -04:00
up.c
user_namespace.c	treewide: kmalloc() -> kmalloc_array()	2018-06-12 16:19:22 -07:00
user-return-notifier.c
user.c	efivarfs: Limit the rate for non-root to read files	2018-02-22 10:21:02 -08:00
utsname_sysctl.c
utsname.c	uts: create "struct uts_namespace" from kmem_cache	2018-04-11 10:28:35 -07:00
watchdog_hld.c
watchdog.c
workqueue_internal.h	workqueue: Set worker->desc to workqueue name by default	2018-05-18 08:47:13 -07:00
workqueue.c	treewide: kzalloc() -> kcalloc()	2018-06-12 16:19:22 -07:00