kernel/linux.git/include/linux/cpumask.h, branch v6.19.11

Merge tag 'bitmap-for-6.19' of github.com:/norov/linux

2025-12-06T17:01:27+00:00

Pull bitmap updates from Yury Norov: - Runtime field_{get,prep}() (Geert) - Rust ID pool updates (Alice) - min_t() simplification (David) - __sw_hweightN kernel-doc fixes (Andy) - cpumask.h headers cleanup (Andy) * tag 'bitmap-for-6.19' of github.com:/norov/linux: (32 commits) rust_binder: use bitmap for allocation of handles rust: id_pool: do not immediately acquire new ids rust: id_pool: do not supply starting capacity rust: id_pool: rename IdPool::new() to with_capacity() rust: bitmap: add BitmapVec::new_inline() rust: bitmap: add MAX_LEN and MAX_INLINE_LEN constants cpumask: Don't use "proxy" headers soc: renesas: Use bitfield helpers clk: renesas: Use bitfield helpers ALSA: usb-audio: Convert to common field_{get,prep}() helpers soc: renesas: rz-sysc: Convert to common field_get() helper pinctrl: ma35: Convert to common field_{get,prep}() helpers iio: mlx90614: Convert to common field_{get,prep}() helpers iio: dac: Convert to common field_prep() helper gpio: aspeed: Convert to common field_{get,prep}() helpers EDAC/ie31200: Convert to common field_get() helper crypto: qat - convert to common field_get() helper clk: at91: Convert to common field_{get,prep}() helpers bitfield: Add non-constant field_{prep,get}() helpers bitfield: Add less-checking __FIELD_{GET,PREP}() ...

Merge tag 'timers-core-2025-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-12-02T17:58:33+00:00

Pull timer core updates from Thomas Gleixner: - Prevent a thundering herd problem when the timekeeper CPU is delayed and a large number of CPUs compete to acquire jiffies_lock to do the update. Limit it to one CPU with a separate "uncontended" atomic variable. - A set of improvements for the timer migration mechanism: - Support imbalanced NUMA trees correctly - Support dynamic exclusion of CPUs from the migrator duty to allow the cpuset/isolation mechanism to exclude them from handling timers of remote idle CPUs - The usual small updates, cleanups and enhancements * tag 'timers-core-2025-11-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timers/migration: Exclude isolated cpus from hierarchy cpumask: Add initialiser to use cleanup helpers sched/isolation: Force housekeeping if isolcpus and nohz_full don't leave any cgroup/cpuset: Rename update_unbound_workqueue_cpumask() to update_isolation_cpumasks() timers/migration: Use scoped_guard on available flag set/clear timers/migration: Add mask for CPUs available in the hierarchy timers/migration: Rename 'online' bit to 'available' selftests/timers/nanosleep: Add tests for return of remaining time selftests/timers: Clean up kernel version check in posix_timers time: Fix a few typos in time[r] related code comments time: tick-oneshot: Add missing Return and parameter descriptions to kernel-doc hrtimer: Store time as ktime_t in restart block timers/migration: Remove dead code handling idle CPU checking for remote timers timers/migration: Remove unused "cpu" parameter from tmigr_get_group() timers/migration: Assert that hotplug preparing CPU is part of stable active hierarchy timers/migration: Fix imbalanced NUMA trees timers/migration: Remove locking on group connection timers/migration: Convert "while" loops to use "for" tick/sched: Limit non-timekeeper CPUs calling jiffies update

cpumask: Cache num_possible_cpus()

2025-11-25T18:45:40+00:00

Reevaluating num_possible_cpus() over and over does not make sense. That becomes a constant after init as cpu_possible_mask is marked ro_after_init. Cache the value during initialization and provide that for consumption. Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Thomas Gleixner Reviewed-by: Yury Norov Reviewed-by: Mathieu Desnoyers Reviewed-by: Shrikanth Hegde Link: https://patch.msgid.link/20251119172549.578653738@linutronix.de

cpumask: Don't use "proxy" headers

2025-11-24T21:08:18+00:00

Update header inclusions to follow IWYU (Include What You Use) principle. Note that kernel.h is discouraged to be included as it's written at the top of that file. Signed-off-by: Andy Shevchenko Signed-off-by: Yury Norov (NVIDIA)

cpumask: Add initialiser to use cleanup helpers

2025-11-20T19:17:32+00:00

Now we can simplify a code that allocates cpumasks for local needs. Automatic variables have to be initialized at declaration, or at least before any possibility for the logic to return, so that compiler wouldn't try to call an associate destructor function on a random stack number. Because cpumask_var_t, depending on the CPUMASK_OFFSTACK config, is either a pointer or an array, we have to have a macro for initialization. So define a CPUMASK_VAR_NULL macro, which allows to init struct cpumask pointer with NULL when CPUMASK_OFFSTACK is enabled, and effectively a no-op when CPUMASK_OFFSTACK is disabled (initialisation optimised out with -O2). Signed-off-by: Yury Norov Signed-off-by: Gabriele Monaco Signed-off-by: Thomas Gleixner Reviewed-by: Frederic Weisbecker Link: https://patch.msgid.link/20251120145653.296659-7-gmonaco@redhat.com

cpumask: Introduce cpumask_weighted_or()

2025-11-20T11:14:54+00:00

CID management OR's two cpumasks and then calculates the weight on the result. That's inefficient as that has to walk the same stuff twice. As this is done with runqueue lock held, there is a real benefit of speeding this up. Depending on the system this results in 10-20% less cycles spent with runqueue lock held for a 4K cpumask. Provide cpumask_weighted_or() and the corresponding bitmap functions which return the weight of the OR result right away. Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Yury Norov (NVIDIA) Reviewed-by: Mathieu Desnoyers Link: https://patch.msgid.link/20251119172549.448263340@linutronix.de

Merge tag 'bitmap-for-6.17' of https://github.com/norov/linux

2025-07-31T23:52:32+00:00

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()

cpumask: Remove unnecessary cpumask_nth_andnot()

2025-07-31T15:28:03+00:00

Commit 94f753143028("x86/resctrl: Optimize cpumask_any_housekeeping()") switched the only user of cpumask_nth_andnot() to other cpumask functions, but left the function cpumask_nth_andnot() unused. This makes function find_nth_andnot_bit() unused as well. Delete them. Signed-off-by: Shaopeng Tan Signed-off-by: Yury Norov [NVIDIA]

cpumask: introduce cpumask_random()

2025-07-08T23:11:57+00:00

Propagate find_random_bit() to cpumask API. CC: Andrew Morton Signed-off-by: "Yury Norov [NVIDIA]"

cpumask: add cpumask_clear_cpus()

2025-06-26T09:19:15+00:00

When user wants to clear a range in cpumask, the only option the API provides now is a for-loop, like: for_each_cpu_from(cpu, mask) { if (cpu >= ncpus) break; __cpumask_clear_cpu(cpu, mask); } In the bitmap API we have bitmap_clear() for that, which is significantly faster than a for-loop. Propagate it to cpumasks. Signed-off-by: Yury Norov [NVIDIA] Link: https://patch.msgid.link/20250604193947.11834-2-yury.norov@gmail.com Signed-off-by: Leon Romanovsky