mirror-linux/kernel
Sebastian Andrzej Siewior 290e26ec0d tick/common: Align tick period with the HZ tick.
[ Upstream commit e9523a0d81 ]

With HIGHRES enabled tick_sched_timer() is programmed every jiffy to
expire the timer_list timers. This timer is programmed accurate in
respect to CLOCK_MONOTONIC so that 0 seconds and nanoseconds is the
first tick and the next one is 1000/CONFIG_HZ ms later. For HZ=250 it is
every 4 ms and so based on the current time the next tick can be
computed.

This accuracy broke since the commit mentioned below because the jiffy
based clocksource is initialized with higher accuracy in
read_persistent_wall_and_boot_offset(). This higher accuracy is
inherited during the setup in tick_setup_device(). The timer still fires
every 4ms with HZ=250 but timer is no longer aligned with
CLOCK_MONOTONIC with 0 as it origin but has an offset in the us/ns part
of the timestamp. The offset differs with every boot and makes it
impossible for user land to align with the tick.

Align the tick period with CLOCK_MONOTONIC ensuring that it is always a
multiple of 1000/CONFIG_HZ ms.

Fixes: 857baa87b6 ("sched/clock: Enable sched clock early")
Reported-by: Gusenleitner Klaus <gus@keba.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/20230406095735.0_14edn3@linutronix.de
Link: https://lore.kernel.org/r/20230418122639.ikgfvu3f@linutronix.de
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-11 23:03:16 +09:00
..
bpf bpf: Fix incorrect verifier pruning due to missing register precision taints 2023-04-26 14:28:35 +02:00
cgroup cgroup/cpuset: Add cpuset_can_fork() and cpuset_cancel_fork() methods 2023-04-20 12:35:14 +02:00
configs Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
debug mm: remove vmacache 2022-09-26 19:46:18 -07:00
dma - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in 2022-10-10 17:53:04 -07:00
entry entry/rcu: Check TIF_RESCHED _after_ delayed RCU wake-up 2023-03-30 12:49:13 +02:00
events perf/core: Fix the same task check in perf_event_set_output 2023-04-13 16:55:32 +02:00
futex futex: Fix futex_waitv() hrtimer debug object leak on kcalloc error 2023-01-04 11:28:58 +01:00
gcov gcov: add support for checksum field 2022-12-31 13:33:11 +01:00
irq genirq/ipi: Fix NULL pointer deref in irq_data_get_affinity_mask() 2023-03-11 13:55:29 +01:00
kcsan kcsan: avoid passing -g for test 2023-04-06 12:10:35 +02:00
livepatch Livepatching changes for 6.1 2022-10-10 11:36:19 -07:00
locking locking/rwsem: Prevent non-first waiter from spinning in down_write() slowpath 2023-03-10 09:34:06 +01:00
module module: Don't wait for GOING modules 2023-02-01 08:34:37 +01:00
power PM: EM: fix memory leak with using debugfs_lookup() 2023-03-10 09:33:53 +01:00
printk kernel/printk/index.c: fix memory leak with using debugfs_lookup() 2023-03-11 13:55:32 +01:00
rcu rcu: Avoid stack overflow due to __rcu_irq_enter_check_tick() being kprobe-ed 2023-05-11 23:03:02 +09:00
sched sched/fair: Fixes for capacity inversion detection 2023-04-26 14:28:42 +02:00
time tick/common: Align tick period with the HZ tick. 2023-05-11 23:03:16 +09:00
trace tracing: Fix permissions for the buffer_percent file 2023-05-11 23:03:04 +09:00
.gitignore
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
Makefile cfi: Fix CFI failure with KASAN 2022-12-31 13:33:08 +01:00
acct.c acct: fix potential integer overflow in encode_comp_t() 2022-12-31 13:32:58 +01:00
async.c
audit.c audit: use time_after to compare time 2022-08-29 19:47:03 -04:00
audit.h audit: remove selinux_audit_rule_update() declaration 2022-09-07 11:30:15 -04:00
audit_fsnotify.c audit: fix potential double free on error path from fsnotify_add_inode_mark 2022-08-22 18:50:06 -04:00
audit_tree.c
audit_watch.c audit_init_parent(): constify path 2022-09-01 17:39:30 -04:00
auditfilter.c
auditsc.c audit/stable-6.1 PR 20221003 2022-10-04 11:05:43 -07:00
backtracetest.c
bounds.c mm: multi-gen LRU: minimal implementation 2022-09-26 19:46:09 -07:00
capability.c
cfi.c cfi: Switch to -fsanitize=kcfi 2022-09-26 10:13:13 -07:00
compat.c sched_getaffinity: don't assume 'cpumask_size()' is fully initialized 2023-04-06 12:10:40 +02:00
configs.c
context_tracking.c context_tracking: Fix noinstr vs KASAN 2023-03-10 09:33:45 +01:00
cpu.c cpu/hotplug: Do not bail-out in DYING/STARTING sections 2022-12-31 13:31:59 +01:00
cpu_pm.c context_tracking: Take IRQ eqs entrypoints over RCU 2022-07-05 13:32:59 -07:00
crash_core.c vmcoreinfo: add kallsyms_num_syms symbol 2022-08-28 14:02:44 -07:00
crash_dump.c
cred.c
delayacct.c delayacct: support re-entrance detection of thrashing accounting 2022-09-26 19:46:07 -07:00
dma.c
exec_domain.c
exit.c exit: Detect and fix irq disabled state in oops 2023-03-10 09:33:45 +01:00
extable.c context_tracking: Take NMI eqs entrypoints over RCU 2022-07-05 13:32:59 -07:00
fail_function.c kernel/fail_function: fix memory leak with using debugfs_lookup() 2023-03-11 13:55:39 +01:00
fork.c mm: enable maple tree RCU mode by default. 2023-04-13 16:55:40 +02:00
freezer.c freezer,sched: Rewrite core freezer logic 2022-09-07 21:53:50 +02:00
gen_kheaders.sh kbuild: build init/built-in.a just once 2022-09-29 04:40:15 +09:00
groups.c security: Add LSM hook to setgroups() syscall 2022-07-15 18:21:49 +00:00
hung_task.c sched: Fix more TASK_state comparisons 2022-09-30 16:50:39 +02:00
iomem.c
irq_work.c
jump_label.c jump_label: make initial NOP patching the special case 2022-06-24 09:48:55 +02:00
kallsyms.c kcfi updates for v6.1-rc1 2022-10-03 17:11:07 -07:00
kallsyms_internal.h kallsyms: move declarations to internal header 2022-07-17 17:31:39 -07:00
kcmp.c
kcov.c kcov: kmsan: unpoison area->list in kcov_remote_area_put() 2022-10-03 14:03:23 -07:00
kexec.c panic, kexec: make __crash_kexec() NMI safe 2022-09-11 21:55:06 -07:00
kexec_core.c kexec: replace kmap() with kmap_local_page() 2022-09-11 21:55:08 -07:00
kexec_elf.c
kexec_file.c panic, kexec: make __crash_kexec() NMI safe 2022-09-11 21:55:06 -07:00
kexec_internal.h panic, kexec: make __crash_kexec() NMI safe 2022-09-11 21:55:06 -07:00
kheaders.c kheaders: Use array declaration instead of char 2023-05-11 23:03:02 +09:00
kmod.c
kprobes.c kprobes: Fix to handle forcibly unoptimized kprobes on freeing_list 2023-03-10 09:34:27 +01:00
ksysfs.c kexec: turn all kexec_mutex acquisitions into trylocks 2022-09-11 21:55:06 -07:00
kthread.c signal: break out of wait loops on kthread_stop() 2022-10-09 16:01:59 -07:00
latencytop.c latencytop: use the last element of latency_record of system 2022-09-11 21:55:12 -07:00
module_signature.c
notifier.c notifier: Add blocking/atomic_notifier_chain_register_unique_prio() 2022-05-19 19:30:30 +02:00
nsproxy.c Revert "fs/exec: allow to unshare a time namespace on vfork+exec" 2022-09-13 10:38:43 -07:00
padata.c padata: Fix list iterator in padata_do_serial() 2022-12-31 13:32:34 +01:00
panic.c panic: fix the panic_print NMI backtrace setting 2023-03-10 09:34:25 +01:00
params.c
pid.c gfs2: Add glockfd debugfs file 2022-06-29 13:07:16 +02:00
pid_namespace.c rcu-tasks: Fix synchronize_rcu_tasks() VS zap_pid_ns_processes() 2023-03-10 09:32:52 +01:00
profile.c kernel/profile.c: simplify duplicated code in profile_setup() 2022-09-11 21:55:12 -07:00
ptrace.c freezer,sched: Rewrite core freezer logic 2022-09-07 21:53:50 +02:00
range.c
reboot.c kernel/reboot: Add SYS_OFF_MODE_RESTART_PREPARE mode 2022-10-04 15:59:36 +02:00
regset.c
relay.c relayfs: fix out-of-bounds access in relay_file_read 2023-05-11 23:03:03 +09:00
resource.c dax/kmem: Fix leak of memory-hotplug resources 2023-03-10 09:34:25 +01:00
resource_kunit.c
rseq.c rseq: Use pr_warn_once() when deprecated/unknown ABI flags are encountered 2022-11-14 09:58:32 +01:00
scftorture.c
scs.c
seccomp.c
signal.c Scheduler changes for v6.1: 2022-10-10 09:10:28 -07:00
smp.c bitmap patches for v6.1-rc1 2022-10-10 12:49:34 -07:00
smpboot.c smpboot: use atomic_try_cmpxchg in cpu_wait_death and cpu_report_death 2022-09-11 21:55:10 -07:00
smpboot.h
softirq.c context_tracking: Take IRQ eqs entrypoints over RCU 2022-07-05 13:32:59 -07:00
stackleak.c
stacktrace.c
static_call.c
static_call_inline.c
stop_machine.c Scheduler changes in this cycle were: 2022-05-24 11:11:13 -07:00
sys.c kernel/sys.c: fix and improve control flow in __sys_setres[ug]id() 2023-04-26 14:28:39 +02:00
sys_ni.c kernel/sys_ni: add compat entry for fadvise64_64 2022-08-20 15:17:45 -07:00
sysctl-test.c kernel/sysctl-test: use SYSCTL_{ZERO/ONE_HUNDRED} instead of i_{zero/one_hundred} 2022-09-08 16:56:45 -07:00
sysctl.c proc: proc_skip_spaces() shouldn't think it is working on C strings 2022-12-05 12:09:06 -08:00
task_work.c task_work: use try_cmpxchg in task_work_add, task_work_cancel_match and task_work_run 2022-09-11 21:55:10 -07:00
taskstats.c genetlink: start to validate reserved header bytes 2022-08-29 12:47:15 +01:00
torture.c torture: Fix hang during kthread shutdown phase 2023-03-10 09:34:07 +01:00
tracepoint.c tracepoint: Optimize the critical region of mutex_lock in tracepoint_module_coming() 2022-09-26 13:01:18 -04:00
tsacct.c
ucount.c ucounts: Split rlimit and ucount values and max values 2022-05-18 18:24:57 -05:00
uid16.c
uid16.h
umh.c freezer,umh: Fix call_usermode_helper_exec() vs SIGKILL 2023-02-22 12:59:50 +01:00
up.c
user-return-notifier.c
user.c
user_namespace.c ucounts: Split rlimit and ucount values and max values 2022-10-09 16:24:05 -07:00
usermode_driver.c blob_to_mnt(): kern_unmount() is needed to undo kern_mount() 2022-05-19 23:25:47 -04:00
utsname.c
utsname_sysctl.c kernel/utsname_sysctl.c: Fix hostname polling 2022-10-23 12:01:01 -07:00
watch_queue.c watch_queue: fix IOC_WATCH_QUEUE_SET_SIZE alloc error paths 2023-03-17 08:50:30 +01:00
watchdog.c powerpc updates for 6.0 2022-08-06 16:38:17 -07:00
watchdog_hld.c Revert "printk: add functions to prefer direct printing" 2022-06-23 18:41:40 +02:00
workqueue.c workqueue: Protects wq_unbound_cpumask with wq_pool_attach_mutex 2023-03-10 09:32:53 +01:00
workqueue_internal.h