twx-linux/kernel
Xiongfeng Wang e895f8e291 hrtimers: Unconditionally update target CPU base after offline timer migration
When testing softirq based hrtimers on an ARM32 board, with high resolution
mode and NOHZ inactive, softirq based hrtimers fail to expire after being
moved away from an offline CPU:

CPU0				CPU1
				hrtimer_start(..., HRTIMER_MODE_SOFT);
cpu_down(CPU1)			...
				hrtimers_cpu_dying()
				  // Migrate timers to CPU0
				  smp_call_function_single(CPU0, returgger_next_event);
  retrigger_next_event()
    if (!highres && !nohz)
        return;

As retrigger_next_event() is a NOOP when both high resolution timers and
NOHZ are inactive CPU0's hrtimer_cpu_base::softirq_expires_next is not
updated and the migrated softirq timers never expire unless there is a
softirq based hrtimer queued on CPU0 later.

Fix this by removing the hrtimer_hres_active() and tick_nohz_active() check
in retrigger_next_event(), which enforces a full update of the CPU base.
As this is not a fast path the extra cost does not matter.

[ tglx: Massaged change log ]

Fixes: 5c0930ccaad5 ("hrtimers: Push pending hrtimers away from outgoing CPU earlier")
Co-developed-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250805081025.54235-1-wangxiongfeng2@huawei.com
2025-09-09 14:05:16 +02:00
..
bpf bpf: Fix memory leak of bpf_scc_info objects 2025-08-02 09:04:57 -07:00
cgroup cgroup: avoid null de-ref in css_rstat_exit() 2025-08-09 08:46:32 -10:00
configs configs/hardening: Enable CONFIG_INIT_ON_FREE_DEFAULT_ON 2025-07-21 21:41:57 -07:00
debug TTY/Serial driver updates for 6.15-rc1 2025-04-02 18:17:33 -07:00
dma dma/pool: Ensure DMA_DIRECT_REMAP allocations are decrypted 2025-08-13 11:02:10 +02:00
entry ARM: 2025-07-30 17:14:01 -07:00
events perf: Fix the POLL_HUP delivery breakage 2025-09-03 10:10:59 +02:00
futex futex: Move futex_hash_free() back to __mmput() 2025-08-31 11:48:19 +02:00
gcov kbuild: require gcc-8 and binutils-2.30 2025-04-30 21:53:35 +02:00
irq genirq/test: Resolve irq lock inversion warnings 2025-08-06 10:29:48 +02:00
kcsan kcsan: test: Initialize dummy variable 2025-07-23 08:51:32 +02:00
livepatch sched,livepatch: Untangle cond_resched() and live-patching 2025-05-14 13:16:24 +02:00
locking - Make sure sanity checks down in the mutex lock path happen on the correct 2025-08-17 05:57:47 -07:00
module Significant patch series in this pull request: 2025-08-05 16:02:07 +03:00
power drm for 6.17-rc1 2025-07-30 19:26:49 -07:00
printk printk changes for 6.17 2025-08-04 10:54:36 -07:00
rcu rcu: Fix racy re-initialization of irq_work causing hangs 2025-08-11 08:43:49 +05:30
sched sched: Fix sched_numa_find_nth_cpu() if mask offline 2025-09-03 12:20:06 -04:00
time hrtimers: Unconditionally update target CPU base after offline timer migration 2025-09-09 14:05:16 +02:00
trace tracing fixes for v6.17-rc2: 2025-08-23 10:11:34 -04:00
unwind unwind: Finish up unwind when a task exits 2025-07-31 10:20:11 -04:00
.gitignore kheaders: rebuild kheaders_data.tar.xz when a file is modified within a minute 2025-06-24 20:30:37 +09:00
acct.c acct: block access to kernel internal filesystems 2025-02-12 12:24:16 +01:00
async.c
audit_fsnotify.c
audit_tree.c replace collect_mounts()/drop_collected_mounts() with a safer variant 2025-06-23 14:01:49 -04:00
audit_watch.c fs: add kern_path_locked_negative() 2025-04-15 11:32:34 +02:00
audit.c audit: record AUDIT_ANOM_* events regardless of presence of rules 2025-04-11 14:14:41 -04:00
audit.h audit,module: restore audit logging in load failure case 2025-06-16 17:00:06 -04:00
auditfilter.c audit: fix out-of-bounds read in audit_compare_dname_path() 2025-09-03 16:46:23 -04:00
auditsc.c audit,module: restore audit logging in load failure case 2025-06-16 17:00:06 -04:00
backtracetest.c
bounds.c
capability.c capability: Remove unused has_capability 2025-03-07 22:03:09 -06:00
cfi.c cfi: Move BPF CFI types and helpers to generic code 2025-07-31 18:23:53 -07:00
compat.c
configs.c
context_tracking.c context_tracking: Make RCU watch ct_kernel_exit_state() warning 2025-03-04 18:44:29 -08:00
cpu_pm.c
cpu.c cpu: Remove obsolete comment from takedown_cpu() 2025-08-06 22:48:12 +02:00
crash_core.c kdump: wait for DMA to finish when using CMA 2025-07-19 19:08:23 -07:00
crash_dump_dm_crypt.c crash_dump: retrieve dm crypt keys in kdump kernel 2025-05-21 10:48:21 -07:00
crash_reserve.c kdump: implement reserve_crashkernel_cma 2025-07-19 19:08:23 -07:00
cred.c
delayacct.c delayacct: remove redundant code and adjust indentation 2025-05-27 19:40:33 -07:00
dma.c
elfcorehdr.c
exec_domain.c
exit.c Significant patch series in this pull request: 2025-08-03 16:23:09 -07:00
exit.h
extable.c
fail_function.c
fork.c futex: Move futex_hash_free() back to __mmput() 2025-08-31 11:48:19 +02:00
freezer.c sched,freezer: Remove unnecessary warning in __thaw_task 2025-07-17 07:56:50 -10:00
gen_kheaders.sh kheaders: make it possible to override TAR 2025-08-06 10:23:36 +09:00
groups.c
hung_task.c hung_task: extend hung task blocker tracking to rwsems 2025-07-19 19:08:26 -07:00
iomem.c mm/memremap: Pass down MEMREMAP_* flags to arch_memremap_wb() 2025-02-21 15:05:38 +01:00
irq_work.c kasan: make kasan_record_aux_stack_noalloc() the default behaviour 2025-01-13 22:40:36 -08:00
jump_label.c jump_label: Use RCU in all users of __module_text_address(). 2025-03-10 11:54:46 +01:00
kallsyms_internal.h
kallsyms_selftest.c kallsyms: Use kthread_run_on_cpu() 2025-01-02 22:12:12 +01:00
kallsyms_selftest.h
kallsyms.c bpf: Clean up individual BTF_ID code 2025-07-16 18:34:42 -07:00
kcmp.c kcmp: improve performance adding an unlikely hint to task comparisons 2025-02-21 10:25:33 +01:00
Kconfig.freezer
Kconfig.hz kernel: Fix "select" wording on HZ_250 description 2025-02-21 09:20:30 +01:00
Kconfig.kexec kho: mm: don't allow deferred struct page with KHO 2025-08-19 16:35:53 -07:00
Kconfig.locks
Kconfig.preempt
kcov.c kcov: fix typo in comment of kcov_fault_in_area 2025-07-09 22:57:52 -07:00
kexec_core.c Significant patch series in this pull request: 2025-08-03 16:23:09 -07:00
kexec_elf.c kexec: initialize ELF lowest address to ULONG_MAX 2025-03-16 22:30:47 -07:00
kexec_file.c Significant patch series in this pull request: 2025-08-03 16:23:09 -07:00
kexec_handover.c kho: warn if KHO is disabled due to an error 2025-08-19 16:35:53 -07:00
kexec_internal.h kexec: enable CMA based contiguous allocation 2025-08-02 12:01:38 -07:00
kexec.c kexec: enable CMA based contiguous allocation 2025-08-02 12:01:38 -07:00
kheaders.c kheaders: Simplify attribute through __BIN_ATTR_SIMPLE_RO() 2024-12-24 09:46:49 +01:00
kprobes.c kprobes: Add missing kerneldoc for __get_insn_slot 2025-07-15 18:45:34 +09:00
kstack_erase.c stackleak: Rename stackleak_track_stack to __sanitizer_cov_stack_depth 2025-07-21 21:40:39 -07:00
ksyms_common.c
ksysfs.c kernel/ksysfs.c: simplify bin_attribute definition 2025-01-07 16:59:15 +01:00
kthread.c ipvs: Fix estimator kthreads preferred affinity 2025-08-13 08:34:33 +02:00
latencytop.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
Makefile Kbuild updates for v6.17 2025-08-06 07:32:52 +03:00
module_signature.c
notifier.c
nsproxy.c kernel/nsproxy: remove unnecessary guards 2025-05-09 13:13:54 +02:00
padata.c padata: use cpumask_nth() 2025-06-13 17:26:17 +08:00
panic.c Significant patch series in this pull request: 2025-08-03 16:23:09 -07:00
params.c params: Replace deprecated strcpy() with strscpy() and memcpy() 2025-08-16 21:47:25 +02:00
pid_namespace.c pid: Do not set pid_max in new pid namespaces 2025-03-06 10:18:36 +01:00
pid_sysctl.h treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
pid.c Summary 2025-07-29 21:43:08 -07:00
profile.c
ptrace.c ptrace: introduce PTRACE_SET_SYSCALL_INFO request 2025-05-11 17:48:15 -07:00
range.c
reboot.c - The 7 patch series "powerpc/crash: use generic crashkernel 2025-04-01 10:06:52 -07:00
regset.c
relay.c relayfs: support a counter tracking if data is too big to write 2025-07-09 22:57:52 -07:00
resource_kunit.c
resource.c resource: fix false warning in __request_region() 2025-07-24 17:57:59 -07:00
rseq.c rseq: Fix segfault on registration when rseq_cs is non-zero 2025-03-06 22:26:49 +01:00
scftorture.c
scs.c
seccomp.c seccomp: avoid the lock trip seccomp_filter_release in common case 2025-02-24 11:17:10 -08:00
signal.c signal: Fix memory leak for PIDFD_SELF* sentinels 2025-08-19 13:51:28 +02:00
smp.c smp: Fix spelling in on_each_cpu_cond_mask()'s doc-comment 2025-08-02 14:24:50 +02:00
smpboot.c sched/smp: Use the SMP version of idle_thread_set_boot_cpu() 2025-06-13 08:47:20 +02:00
smpboot.h
softirq.c lockdep: Fix wait context check on softirq for PREEMPT_RT 2025-03-25 10:46:44 +01:00
stacktrace.c
static_call_inline.c Modules changes for 6.15-rc1 2025-03-30 15:44:36 -07:00
static_call.c
stop_machine.c sched/core: Fix migrate_swap() vs. hotplug 2025-07-01 15:02:03 +02:00
sys_ni.c
sys.c Summary of significant series in this pull request: 2025-07-31 14:57:54 -07:00
sysctl-test.c sysctl: move u8 register test to lib/test_sysctl.c 2025-04-14 14:13:41 +02:00
sysctl.c sysctl: rename kern_table -> sysctl_subsys_table 2025-07-23 11:56:02 +02:00
task_work.c kasan: make kasan_record_aux_stack_noalloc() the default behaviour 2025-01-13 22:40:36 -08:00
taskstats.c
torture.c torture: Add get_torture_init_jiffies() for test-start time 2025-02-05 07:14:24 -08:00
tracepoint.c tracepoint: Print the function symbol when tracepoint_debug is set 2025-03-21 15:30:10 -04:00
tsacct.c
ucount.c ucount: use atomic_long_try_cmpxchg() in atomic_long_inc_below() 2025-08-02 12:01:38 -07:00
uid16.c
uid16.h
umh.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
up.c
user_namespace.c uidgid: add map_id_range_up() 2025-02-12 12:12:27 +01:00
user-return-notifier.c
user.c
utsname_sysctl.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
utsname.c
vhost_task.c vhost: Use ERR_CAST inlined function instead of ERR_PTR(PTR_ERR(...)) 2025-08-01 09:11:08 -04:00
vmcore_info.c crash: export PAGE_UNACCEPTED_MAPCOUNT_VALUE to vmcoreinfo 2025-05-11 17:54:04 -07:00
watch_queue.c vfs-6.15-rc1.pipe 2025-03-24 09:52:37 -07:00
watchdog_buddy.c watchdog: fix opencoded cpumask_next_wrap() in watchdog_next_cpu() 2025-07-31 11:28:03 -04:00
watchdog_perf.c watchdog/perf: Provide function for adjusting the event period 2025-07-04 13:17:30 +01:00
watchdog.c kernel/watchdog: add /sys/kernel/{hard,soft}lockup_count 2025-05-21 10:48:22 -07:00
workqueue_internal.h
workqueue.c workqueue: Changes for v6.17 2025-07-31 15:40:22 -07:00