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2025-12-07timekeeping: Fix error code in tk_aux_sysfs_init()Dan Carpenter1-1/+3
commit c7418164b463056bf4327b6a2abe638b78250f13 upstream. If kobject_create_and_add() fails on the first iteration, then the error code is set to -ENOMEM which is correct. But if it fails in subsequent iterations then "ret" is zero, which means success, but it should be -ENOMEM. Set the error code to -ENOMEM correctly. Fixes: 7b5ab04f035f ("timekeeping: Fix resource leak in tk_aux_sysfs_init() error paths") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Malaya Kumar Rout <mrout@redhat.com> Link: https://patch.msgid.link/aSW1R8q5zoY_DgQE@stanley.mountain Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-12-01timekeeping: Fix resource leak in tk_aux_sysfs_init() error pathsMalaya Kumar Rout1-9/+12
[ Upstream commit 7b5ab04f035f829ed6008e4685501ec00b3e73c9 ] tk_aux_sysfs_init() returns immediately on error during the auxiliary clock initialization loop without cleaning up previously allocated kobjects and sysfs groups. If kobject_create_and_add() or sysfs_create_group() fails during loop iteration, the parent kobjects (tko and auxo) and any previously created child kobjects are leaked. Fix this by adding proper error handling with goto labels to ensure all allocated resources are cleaned up on failure. kobject_put() on the parent kobjects will handle cleanup of their children. Fixes: 7b95663a3d96 ("timekeeping: Provide interface to control auxiliary clocks") Signed-off-by: Malaya Kumar Rout <mrout@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://patch.msgid.link/20251120150213.246777-1-mrout@redhat.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-12-01tick/sched: Fix bogus condition in report_idle_softirq()Wen Yang1-6/+5
[ Upstream commit 807e0d187da4c0b22036b5e34000f7a8c52f6e50 ] In commit 0345691b24c0 ("tick/rcu: Stop allowing RCU_SOFTIRQ in idle") the new function report_idle_softirq() was created by breaking code out of the existing can_stop_idle_tick() for kernels v5.18 and newer. In doing so, the code essentially went from this form: if (A) { static int ratelimit; if (ratelimit < 10 && !C && A&D) { pr_warn("NOHZ tick-stop error: ..."); ratelimit++; } return false; } to a new function: static bool report_idle_softirq(void) { static int ratelimit; if (likely(!A)) return false; if (ratelimit < 10) return false; ... pr_warn("NOHZ tick-stop error: local softirq work is pending, handler #%02x!!!\n", pending); ratelimit++; return true; } commit a7e282c77785 ("tick/rcu: Fix bogus ratelimit condition") realized ratelimit was essentially set to zero instead of ten, and hence *no* softirq pending messages would ever be issued, but "fixed" it as: - if (ratelimit < 10) + if (ratelimit >= 10) return false; However, this fix introduced another issue: When ratelimit is greater than or equal 10, even if A is true, it will directly return false. While ratelimit in the original code was only used to control printing and will not affect the return value. Restore the original logic and restrict ratelimit to control the printk and not the return value. Fixes: 0345691b24c0 ("tick/rcu: Stop allowing RCU_SOFTIRQ in idle") Fixes: a7e282c77785 ("tick/rcu: Fix bogus ratelimit condition") Signed-off-by: Wen Yang <wen.yang@linux.dev> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://patch.msgid.link/20251119174525.29470-1-wen.yang@linux.dev Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-12-01timers: Fix NULL function pointer race in timer_shutdown_sync()Yipeng Zou1-3/+4
commit 20739af07383e6eb1ec59dcd70b72ebfa9ac362c upstream. There is a race condition between timer_shutdown_sync() and timer expiration that can lead to hitting a WARN_ON in expire_timers(). The issue occurs when timer_shutdown_sync() clears the timer function to NULL while the timer is still running on another CPU. The race scenario looks like this: CPU0 CPU1 <SOFTIRQ> lock_timer_base() expire_timers() base->running_timer = timer; unlock_timer_base() [call_timer_fn enter] mod_timer() ... timer_shutdown_sync() lock_timer_base() // For now, will not detach the timer but only clear its function to NULL if (base->running_timer != timer) ret = detach_if_pending(timer, base, true); if (shutdown) timer->function = NULL; unlock_timer_base() [call_timer_fn exit] lock_timer_base() base->running_timer = NULL; unlock_timer_base() ... // Now timer is pending while its function set to NULL. // next timer trigger <SOFTIRQ> expire_timers() WARN_ON_ONCE(!fn) // hit ... lock_timer_base() // Now timer will detach if (base->running_timer != timer) ret = detach_if_pending(timer, base, true); if (shutdown) timer->function = NULL; unlock_timer_base() The problem is that timer_shutdown_sync() clears the timer function regardless of whether the timer is currently running. This can leave a pending timer with a NULL function pointer, which triggers the WARN_ON_ONCE(!fn) check in expire_timers(). Fix this by only clearing the timer function when actually detaching the timer. If the timer is running, leave the function pointer intact, which is safe because the timer will be properly detached when it finishes running. Fixes: 0cc04e80458a ("timers: Add shutdown mechanism to the internal functions") Signed-off-by: Yipeng Zou <zouyipeng@huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20251122093942.301559-1-zouyipeng@huawei.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-11-24posix-timers: Plug potential memory leak in do_timer_create()Eslam Khafagy1-6/+6
[ Upstream commit e0fd4d42e27f761e9cc82801b3f183e658dc749d ] When posix timer creation is set to allocate a given timer ID and the access to the user space value faults, the function terminates without freeing the already allocated posix timer structure. Move the allocation after the user space access to cure that. [ tglx: Massaged change log ] Fixes: ec2d0c04624b3 ("posix-timers: Provide a mechanism to allocate a given timer ID") Reported-by: syzbot+9c47ad18f978d4394986@syzkaller.appspotmail.com Suggested-by: Cyrill Gorcunov <gorcunov@gmail.com> Signed-off-by: Eslam Khafagy <eslam.medhat1993@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://patch.msgid.link/20251114122739.994326-1-eslam.medhat1993@gmail.com Closes: https://lore.kernel.org/all/69155df4.a70a0220.3124cb.0017.GAE@google.com/T/ Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02timekeeping: Fix aux clocks sysfs initialization loop boundHaofeng Li1-1/+1
[ Upstream commit 39a9ed0fb6dac58547afdf9b6cb032d326a3698f ] The loop in tk_aux_sysfs_init() uses `i <= MAX_AUX_CLOCKS` as the termination condition, which results in 9 iterations (i=0 to 8) when MAX_AUX_CLOCKS is defined as 8. However, the kernel is designed to support only up to 8 auxiliary clocks. This off-by-one error causes the creation of a 9th sysfs entry that exceeds the intended auxiliary clock range. Fix the loop bound to use `i < MAX_AUX_CLOCKS` to ensure exactly 8 auxiliary clock entries are created, matching the design specification. Fixes: 7b95663a3d96 ("timekeeping: Provide interface to control auxiliary clocks") Signed-off-by: Haofeng Li <lihaofeng@kylinos.cn> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://patch.msgid.link/tencent_2376993D9FC06A3616A4F981B3DE1C599607@qq.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15tick: Do not set device to detached state in tick_shutdown()Bibo Mao3-13/+7
[ Upstream commit fe2a449a45b13df1562419e0104b4777b6ea5248 ] tick_shutdown() sets the state of the clockevent device to detached first and the invokes clockevents_exchange_device(), which in turn invokes clockevents_switch_state(). But clockevents_switch_state() returns without invoking the device shutdown callback as the device is already in detached state. As a consequence the timer device is not shutdown when a CPU goes offline. tick_shutdown() does this because it was originally invoked on a online CPU and not on the outgoing CPU. It therefore could not access the clockevent device of the already offlined CPU and just set the state. Since commit 3b1596a21fbf tick_shutdown() is called on the outgoing CPU, so the hardware device can be accessed. Remove the state set before calling clockevents_exchange_device(), so that the subsequent clockevents_switch_state() handles the state transition and invokes the shutdown callback of the clockevent device. [ tglx: Massaged change log ] Fixes: 3b1596a21fbf ("clockevents: Shutdown and unregister current clockevents at CPUHP_AP_TICK_DYING") Signed-off-by: Bibo Mao <maobibo@loongson.cn> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: https://lore.kernel.org/all/20250906064952.3749122-2-maobibo@loongson.cn Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-09-09hrtimers: Unconditionally update target CPU base after offline timer migrationXiongfeng Wang1-8/+3
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
2025-09-03vdso/vsyscall: Avoid slow division loop in auxiliary clock updateThomas Weißschuh2-4/+10
The call to __iter_div_u64_rem() in vdso_time_update_aux() is a wrapper around subtraction. It cannot be used to divide large numbers, as that introduces long, computationally expensive delays. A regular u64 division is also not possible in the timekeeper update path as it can be too slow. Instead of splitting the ktime_t offset into into second and subsecond components during the timekeeper update fast-path, do it together with the adjustment of tk->offs_aux in the slow-path. Equivalent to the handling of offs_boot and monotonic_to_boot. Reuse the storage of monotonic_to_boot for the new field, as it is not used by auxiliary timekeepers. Fixes: 380b84e168e5 ("vdso/vsyscall: Update auxiliary clock data in the datapage") Reported-by: Miroslav Lichvar <mlichvar@redhat.com> Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250825-vdso-auxclock-division-v1-1-a1d32a16a313@linutronix.de Closes: https://lore.kernel.org/lkml/aKwsNNWsHJg8IKzj@localhost/
2025-07-31Merge tag 'bitmap-for-6.17' of https://github.com/norov/linuxLinus Torvalds1-4/+1
Pull bitmap updates from Yury Norov: - find_random_bit() series (Yury) - GENMASK() consolidation (Vincent) - random cleanups (Shaopeng, Ben, Yury) * tag 'bitmap-for-6.17' of https://github.com/norov/linux: bitfield: Ensure the return values of helper functions are checked test_bits: add tests for __GENMASK() and __GENMASK_ULL() bits: unify the non-asm GENMASK*() bits: split the definition of the asm and non-asm GENMASK*() cpumask: Remove unnecessary cpumask_nth_andnot() watchdog: fix opencoded cpumask_next_wrap() in watchdog_next_cpu() clocksource: Improve randomness in clocksource_verify_choose_cpus() cpumask: introduce cpumask_random() bitmap: generalize node_random()
2025-07-31clocksource: Improve randomness in clocksource_verify_choose_cpus()Yury Norov [NVIDIA]1-4/+1
The current algorithm of picking a random CPU works OK for dense online cpumask, but if cpumask is non-dense, the distribution of picked CPUs is skewed. For example, on 8-CPU board with CPUs 4-7 offlined, the probability of selecting CPU 0 is 5/8. Accordingly, cpus 1, 2 and 3 are chosen with probability 1/8 each. The proper algorithm should pick each online CPU with probability 1/4. Switch it to cpumask_random(), which has better statistical characteristics. CC: Andrew Morton <akpm@linux-foundation.org> Acked-by: John Stultz <jstultz@google.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: "Yury Norov [NVIDIA]" <yury.norov@gmail.com>
2025-07-29Merge tag 'timers-ptp-2025-07-27' of ↵Linus Torvalds9-131/+680
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timekeeping and VDSO updates from Thomas Gleixner: - Introduce support for auxiliary timekeepers PTP clocks can be disconnected from the universal CLOCK_TAI reality for various reasons including regularatory requirements for functional safety redundancy. The kernel so far only supports a single notion of time, which means that all clocks are correlated in frequency and only differ by offset to each other. Access to non-correlated PTP clocks has been available so far only through the file descriptor based "POSIX clock IDs", which are subject to locking and have to go all the way out to the hardware. The access is not only horribly slow, as it has to go all the way out to the NIC/PTP hardware, but that also prevents the kernel to read the time of such clocks e.g. from the network stack, where it is required for TSN networking both on the transmit and receive side unless the hardware provides offloading. The auxiliary clocks provide a mechanism to support arbitrary clocks which are not correlated to the system clock. This is not restricted to the PTP use case on purpose as there is no kernel side association of these clocks to a particular PTP device because that's a pure user space configuration decision. Having them independent allows to utilize them for other purposes and also enables them to be tested without hardware dependencies. To avoid pointless overhead these clocks have to be enabled individualy via a new sysfs interface to reduce the overhead to a single compare in the hotpath if they are enabled at the Kconfig level at all. These clocks utilize the existing timekeeping/NTP infrastructures, which has been made possible over the recent releases by incrementaly converting these infrastructures over from a single static instance to a multi-instance pointer based implementation without any performance regression reported. The auxiliary clocks provide the same "emulation" of a "correct" clock as the existing CLOCK_* variants do with an independent instance of data and provide the same steering mechanism through the existing sys_clock_adjtime() interface, which has been confirmed to work by the chronyd(8) maintainer. That allows to provide lockless kernel internal and VDSO support so that applications and kernel internal functionalities can access these clocks without restrictions and at the same performance as the existing system clocks. - Avoid double notifications in the adjtimex() syscall. Not a big issue, but a trivial to avoid latency source. * tag 'timers-ptp-2025-07-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits) vdso/gettimeofday: Add support for auxiliary clocks vdso/vsyscall: Update auxiliary clock data in the datapage vdso: Introduce aux_clock_resolution_ns() vdso/gettimeofday: Introduce vdso_get_timestamp() vdso/gettimeofday: Introduce vdso_set_timespec() vdso/gettimeofday: Introduce vdso_clockid_valid() vdso/gettimeofday: Return bool from clock_gettime() helpers vdso/gettimeofday: Return bool from clock_getres() helpers vdso/helpers: Add helpers for seqlocks of single vdso_clock vdso/vsyscall: Split up __arch_update_vsyscall() into __arch_update_vdso_clock() vdso/vsyscall: Introduce a helper to fill clock configurations timekeeping: Remove the temporary CLOCK_AUX workaround timekeeping: Provide ktime_get_clock_ts64() timekeeping: Provide interface to control auxiliary clocks timekeeping: Provide update for auxiliary timekeepers timekeeping: Provide adjtimex() for auxiliary clocks timekeeping: Prepare do_adtimex() for auxiliary clocks timekeeping: Make do_adjtimex() reusable timekeeping: Add auxiliary clock support to __timekeeping_inject_offset() timekeeping: Make timekeeping_inject_offset() reusable ...
2025-07-29Merge tag 'timers-core-2025-07-27' of ↵Linus Torvalds2-19/+12
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer core updates from Thomas Gleixner: - Simplify the logic in the timer migration code - Simplify the clocksource code by utilizing the more modern cpumask+*() interfaces * tag 'timers-core-2025-07-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: clocksource: Use cpumask_next_wrap() in clocksource_watchdog() clocksource: Use cpumask_any_but() in clocksource_verify_choose_cpus() timers/migration: Clean up the loop in tmigr_quick_check()
2025-07-29Merge tag 'timers-cleanups-2025-07-27' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer cleanups from Thomas Gleixner: "A treewide cleanup of struct cycle_counter const annotations. The initial idea of making them const was correct as they were seperate instances. When they got embedded into larger data structures, which are even modified by the callback this got moot. The only reason why this went unnoticed is that the required container_of() casts the const attribute forcefully away. Stop pretending that it is const" * tag 'timers-cleanups-2025-07-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: time/timecounter: Fix the lie that struct cyclecounter is const
2025-07-22timekeeping: Zero initialize system_counterval when querying time from phc ↵Markus Blöchl1-1/+1
drivers Most drivers only populate the fields cycles and cs_id of system_counterval in their get_time_fn() callback for get_device_system_crosststamp(), unless they explicitly provide nanosecond values. When the use_nsecs field was added to struct system_counterval, most drivers did not care. Clock sources other than CSID_GENERIC could then get converted in convert_base_to_cs() based on an uninitialized use_nsecs field, which usually results in -EINVAL during the following range check. Pass in a fully zero initialized system_counterval_t to cure that. Fixes: 6b2e29977518 ("timekeeping: Provide infrastructure for converting to/from a base clock") Signed-off-by: Markus Blöchl <markus@blochl.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20250720-timekeeping_uninit_crossts-v2-1-f513c885b7c2@blochl.de
2025-07-18vdso/vsyscall: Update auxiliary clock data in the datapageThomas Weißschuh3-0/+57
Expose the auxiliary clock data so it can be read from the vDSO. Architectures not using the generic vDSO time framework, namely SPARC64, are not supported. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250701-vdso-auxclock-v1-11-df7d9f87b9b8@linutronix.de
2025-07-18vdso: Introduce aux_clock_resolution_ns()Thomas Weißschuh1-2/+4
Move the constant resolution to a shared header, so the vDSO can use it and return it without going through a syscall. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250701-vdso-auxclock-v1-10-df7d9f87b9b8@linutronix.de
2025-07-09vdso/vsyscall: Split up __arch_update_vsyscall() into __arch_update_vdso_clock()Thomas Weißschuh1-1/+2
The upcoming auxiliary clocks need this hook, too. To separate the architecture hooks from the timekeeper internals, refactor the hook to only operate on a single vDSO clock. While at it, use a more robust #define for the hook override. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250701-vdso-auxclock-v1-3-df7d9f87b9b8@linutronix.de
2025-07-09vdso/vsyscall: Introduce a helper to fill clock configurationsThomas Weißschuh1-14/+13
The logic to configure a 'struct vdso_clock' from a 'struct tk_read_base' is copied two times. Split it into a shared function to reduce the duplication, especially as another user will be added for auxiliary clocks. Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250701-vdso-auxclock-v1-2-df7d9f87b9b8@linutronix.de
2025-07-09Merge v6.16-rc2 into timers/ptpThomas Gleixner1-0/+9
to pick up the __GENMASK() fix, otherwise the AUX clock VDSO patches fail to compile for compat. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2025-07-03Merge tag 'ktime-get-clock-ts64-for-ptp' into timers/ptpThomas Gleixner1-0/+34
Pull the base implementation of ktime_get_clock_ts64() for PTP, which contains a temporary CLOCK_AUX* workaround. That was created to allow integration of depending changes into the networking tree. The workaround is going to be removed in a subsequent change in the timekeeping tree. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2025-07-03timekeeping: Provide ktime_get_clock_ts64()Thomas Gleixner1-0/+33
PTP implements an inline switch case for taking timestamps from various POSIX clock IDs, which already consumes quite some text space. Expanding it for auxiliary clocks really becomes too big for inlining. Provide a out of line version. The function invalidates the timestamp in case the clock is invalid. The invalidation allows to implement a validation check without the need to propagate a return value through deep existing call chains. Due to merge logistics this temporarily defines CLOCK_AUX[_LAST] if undefined, so that the plain branch, which does not contain any of the core timekeeper changes, can be pulled into the networking tree as prerequisite for the PTP side changes. These temporary defines are removed after that branch is merged into the tip::timers/ptp branch. That way the result in -next or upstream in the next merge window has zero dependencies. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250701132628.357686408@linutronix.de
2025-07-01time/timecounter: Fix the lie that struct cyclecounter is constGreg Kroah-Hartman1-1/+1
In both the read callback for struct cyclecounter, and in struct timecounter, struct cyclecounter is declared as a const pointer. Unfortunatly, a number of users of this pointer treat it as a non-const pointer as it is burried in a larger structure that is heavily modified by the callback function when accessed. This lie had been hidden by the fact that container_of() "casts away" a const attribute of a pointer without any compiler warning happening at all. Fix this all up by removing the const attribute in the needed places so that everyone can see that the structure really isn't const, but can, and is, modified by the users of it. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/2025070124-backyard-hurt-783a@gregkh
2025-06-27timekeeping: Provide interface to control auxiliary clocksThomas Gleixner1-0/+116
Auxiliary clocks are disabled by default and attempts to access them fail. Provide an interface to enable/disable them at run-time. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183758.444626478@linutronix.de
2025-06-27timekeeping: Provide update for auxiliary timekeepersThomas Gleixner1-0/+19
Update the auxiliary timekeepers periodically. For now this is tied to the system timekeeper update from the tick. This might be revisited and moved out of the tick. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183758.382451331@linutronix.de
2025-06-27timekeeping: Provide adjtimex() for auxiliary clocksThomas Gleixner1-0/+16
The behaviour is close to clock_adtime(CLOCK_REALTIME) with the following differences: 1) ADJ_SETOFFSET adjusts the auxiliary clock offset 2) ADJ_TAI is not supported 3) Leap seconds are not supported 4) PPS is not supported Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183758.317946543@linutronix.de
2025-06-27timekeeping: Prepare do_adtimex() for auxiliary clocksThomas Gleixner1-3/+33
Exclude ADJ_TAI, leap seconds and PPS functionality as they make no sense in the context of auxiliary clocks and provide a time stamp based on the actual clock. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183758.253203783@linutronix.de
2025-06-27timekeeping: Make do_adjtimex() reusableThomas Gleixner1-46/+56
Split out the actual functionality of adjtimex() and make do_adjtimex() a wrapper which feeds the core timekeeper into it and handles the result including audit at the call site. This allows to reuse the actual functionality for auxiliary clocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183758.187322876@linutronix.de
2025-06-27timekeeping: Add auxiliary clock support to __timekeeping_inject_offset()Thomas Gleixner1-8/+31
Redirect the relative offset adjustment to the auxiliary clock offset instead of modifying CLOCK_REALTIME, which has no meaning in context of these clocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183758.124057787@linutronix.de
2025-06-27timekeeping: Make timekeeping_inject_offset() reusableThomas Gleixner1-11/+15
Split out the inner workings for auxiliary clock support and feed the core time keeper into it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183758.059934561@linutronix.de
2025-06-27timekeeping: Provide time setter for auxiliary clocksThomas Gleixner1-0/+44
Add clock_settime(2) support for auxiliary clocks. The function affects the AUX offset which is added to the "monotonic" clock readout of these clocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183757.995688714@linutronix.de
2025-06-27timekeeping: Add minimal posix-timers support for auxiliary clocksThomas Gleixner3-0/+25
Provide clock_getres(2) and clock_gettime(2) for auxiliary clocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183757.932220594@linutronix.de
2025-06-27timekeeping: Provide time getters for auxiliary clocksThomas Gleixner1-0/+65
Provide interfaces similar to the ktime_get*() family which provide access to the auxiliary clocks. These interfaces have a boolean return value, which indicates whether the accessed clock is valid or not. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183757.868342628@linutronix.de
2025-06-27timekeeping: Update auxiliary timekeepers on clocksource changeThomas Gleixner1-0/+33
Propagate a system clocksource change to the auxiliary timekeepers so that they can pick up the new clocksource. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250625183757.803890875@linutronix.de
2025-06-19ntp: Use ktime_get_ntp_seconds()Thomas Gleixner1-2/+2
Use ktime_get_ntp_seconds() to prepare for auxiliary clocks so that the readout becomes per timekeeper. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250519083026.472512636@linutronix.de
2025-06-19timekeeping: Provide ktime_get_ntp_seconds()Thomas Gleixner2-0/+12
ntp_adjtimex() requires access to the actual time keeper per timekeeper ID. Provide an interface. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250519083026.411809421@linutronix.de
2025-06-19timekeeping: Introduce auxiliary timekeepersAnna-Maria Behnsen1-2/+20
Provide timekeepers for auxiliary clocks and initialize them during boot. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250519083026.350061049@linutronix.de
2025-06-19timekeeping: Add clock_valid flag to timekeeperThomas Gleixner1-2/+3
In preparation for supporting independent auxiliary timekeepers, add a clock valid field and set it to true for the system timekeeper. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250519083026.287145536@linutronix.de
2025-06-19timekeeping: Prepare timekeeping_update_from_shadow()Thomas Gleixner1-5/+7
Don't invoke the VDSO and paravirt updates when utilized for auxiliary clocks. This is a temporary workaround until the VDSO and paravirt interfaces have been worked out. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250519083026.223876435@linutronix.de
2025-06-19timekeeping: Make __timekeeping_advance() reusableAnna-Maria Behnsen1-6/+6
In __timekeeping_advance() the pointer to struct tk_data is hardcoded by the use of &tk_core. As long as there is only a single timekeeper (tk_core), this is not a problem. But when __timekeeping_advance() will be reused for per auxiliary timekeepers, __timekeeping_advance() needs to be generalized. Add a pointer to struct tk_data as function argument of __timekeeping_advance() and adapt all call sites. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250519083026.160967312@linutronix.de
2025-06-19ntp: Rename __do_adjtimex() to ntp_adjtimex()Thomas Gleixner3-5/+5
Clean up the name space. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250519083026.095637820@linutronix.de
2025-06-19ntp: Add timekeeper ID arguments to public functionsThomas Gleixner3-26/+30
In preparation for supporting auxiliary POSIX clocks, add a timekeeper ID to the relevant functions. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250519083026.032425931@linutronix.de
2025-06-19ntp: Add support for auxiliary timekeepersThomas Gleixner1-19/+22
If auxiliary clocks are enabled, provide an array of NTP data so that the auxiliary timekeepers can be steered independently of the core timekeeper. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250519083025.969000914@linutronix.de
2025-06-19time: Introduce auxiliary POSIX clocksAnna-Maria Behnsen1-2/+13
To support auxiliary timekeeping and the related user space interfaces, it's required to define a clock ID range for them. Reserve 8 auxiliary clock IDs after the regular timekeeping clock ID space. This is the maximum number of auxiliary clocks the kernel can support. The actual number of supported clocks depends obviously on the presence of related devices and might be constraint by the available VDSO space. Add the corresponding timekeeper IDs as well. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250519083025.905800695@linutronix.de
2025-06-19timekeeping: Introduce timekeeper IDAnna-Maria Behnsen1-2/+3
As long as there is only a single timekeeper, there is no need to clarify which timekeeper is used. But with the upcoming reusage of the timekeeper infrastructure for auxiliary clock timekeepers, an ID is required to differentiate. Introduce an enum for timekeeper IDs, introduce a field in struct tk_data to store this timekeeper id and add also initialization. The id struct field is added at the end of the second cachline, as there is a 4 byte hole anyway. Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250519083025.842476378@linutronix.de
2025-06-19timekeeping: Avoid double notification in do_adjtimex()Thomas Gleixner1-42/+56
Consolidate do_adjtimex() so that it does not notify about clock changes twice. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/all/20250519083025.779267274@linutronix.de
2025-06-19timekeeping: Cleanup kernel doc of __ktime_get_real_seconds()Thomas Gleixner1-3/+8
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250519083025.715836017@linutronix.de
2025-06-19timekeeping: Remove hardcoded access to tk_coreThomas Gleixner1-1/+1
This was overlooked in the initial conversion. Use the provided pointer to access the shadow timekeeper. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250519083025.652611452@linutronix.de
2025-06-14clocksource: Use cpumask_next_wrap() in clocksource_watchdog()Yury Norov [NVIDIA]1-3/+1
cpumask_next_wrap() is more verbose and efficient comparing to cpumask_next() followed by cpumask_first(). Signed-off-by: Yury Norov [NVIDIA] <yury.norov@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250614155031.340988-3-yury.norov@gmail.com
2025-06-14clocksource: Use cpumask_any_but() in clocksource_verify_choose_cpus()Yury Norov [NVIDIA]1-3/+1
cpumask_any_but() is more verbose than cpumask_first() followed by cpumask_next(). Use it in clocksource_verify_choose_cpus(). Signed-off-by: Yury Norov [NVIDIA] <yury.norov@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <jstultz@google.com> Link: https://lore.kernel.org/all/20250614155031.340988-2-yury.norov@gmail.com
generated by cgit v1.2.3 (git 2.25.1) at 2026-03-25 02:52:33 +0000