Breno Leitao 4cdc8a7389 workqueue: set WQ_AFFN_CACHE_SHARD as the default affinity scope ...

Set WQ_AFFN_CACHE_SHARD as the default affinity scope for unbound
workqueues. On systems where many CPUs share one LLC, the previous
default (WQ_AFFN_CACHE) collapses all CPUs to a single worker pool,
causing heavy spinlock contention on pool->lock.

WQ_AFFN_CACHE_SHARD subdivides each LLC into smaller groups, providing
a better balance between locality and contention. Users can revert to
the previous behavior with workqueue.default_affinity_scope=cache.

On systems with 8 or fewer cores per LLC, CACHE_SHARD produces a single
shard covering the entire LLC, making it functionally identical to the
previous CACHE default. The sharding only activates when an LLC has more
than 8 cores.

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Tejun Heo <tj@kernel.org>

2026-04-01 10:24:18 -10:00

..

bpf

Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses

2026-02-22 08:26:33 -08:00

cgroup

Convert 'alloc_flex' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

configs

watchdog: softlockup: panic when lockup duration exceeds N thresholds

2026-01-20 19:44:20 -08:00

debug

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21 01:02:28 -08:00

dma

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

entry

Merge branch 'core/entry' into sched/core

2026-01-30 15:40:05 +01:00

events

Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses

2026-02-22 08:26:33 -08:00

futex

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

gcov

Convert more 'alloc_obj' cases to default GFP_KERNEL arguments

2026-02-21 20:03:00 -08:00

irq

Convert 'alloc_flex' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

kcsan

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

livepatch

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

liveupdate

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

locking

Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses

2026-02-22 08:26:33 -08:00

module

Convert 'alloc_flex' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

power

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

printk

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

rcu

Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses

2026-02-22 08:26:33 -08:00

sched

Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses

2026-02-22 08:26:33 -08:00

time

Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses

2026-02-22 08:26:33 -08:00

trace

Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses

2026-02-22 08:26:33 -08:00

unwind

Convert more 'alloc_obj' cases to default GFP_KERNEL arguments

2026-02-21 20:03:00 -08:00

.gitignore

…

acct.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

async.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

audit_fsnotify.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

audit_tree.c

Convert 'alloc_flex' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

audit_watch.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

audit.c

Convert 'alloc_flex' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

audit.h

audit: fix comment misindentation in audit.h

2025-10-22 19:28:06 -04:00

auditfilter.c

Convert 'alloc_flex' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

auditsc.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

backtracetest.c

…

bounds.c

x86/asm: Remove ANNOTATE_DATA_SPECIAL usage

2025-12-03 16:53:19 +01:00

capability.c

…

cfi.c

…

compat.c

…

configs.c

…

context_tracking.c

context_tracking: Remove rcu_task_trace_heavyweight_{enter,exit}()

2026-01-01 16:39:46 +08:00

cpu_pm.c

syscore: Pass context data to callbacks

2025-11-14 10:01:52 +01:00

cpu.c

Merge tag 'spdx-7.0-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx

2026-02-17 09:46:03 -08:00

crash_core_test.c

crash: add KUnit tests for crash_exclude_mem_range

2025-09-13 17:32:55 -07:00

crash_core.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

crash_dump_dm_crypt.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

crash_reserve.c

crash: let architecture decide crash memory export to iomem_resource

2025-11-12 10:00:15 -08:00

cred.c

cred: remove unused set_security_override_from_ctx()

2026-01-06 20:52:57 -05:00

delayacct.c

delayacct: fix uapi timespec64 definition

2026-02-08 00:13:32 -08:00

dma.c

…

elfcorehdr.c

…

exec_domain.c

…

exit.c

Merge tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2025-12-06 14:01:20 -08:00

exit.h

…

extable.c

…

fail_function.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

fork.c

Merge tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-02-12 12:13:01 -08:00

freezer.c

freezer: Clarify that only cgroup1 freezer uses PM freezer

2025-10-30 20:10:27 +01:00

gen_kheaders.sh

kheaders: make it possible to override TAR

2025-08-06 10:23:36 +09:00

groups.c

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21 01:02:28 -08:00

hung_task.c

hung_task: add hung_task_sys_info sysctl to dump sys info on task-hung

2025-11-20 14:03:43 -08:00

iomem.c

…

irq_work.c

…

jump_label.c

…

kallsyms_internal.h

kallsyms: Get rid of kallsyms relative base

2026-01-22 15:58:22 -07:00

kallsyms_selftest.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

kallsyms_selftest.h

…

kallsyms.c

Merge tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-02-12 12:13:01 -08:00

kcmp.c

…

Kconfig.freezer

…

Kconfig.hz

…

Kconfig.kexec

liveupdate: kho: move to kernel/liveupdate

2025-11-27 14:24:33 -08:00

Kconfig.locks

…

Kconfig.preempt

sched: Further restrict the preemption modes

2026-01-08 12:43:57 +01:00

kcov.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

kexec_core.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

kexec_elf.c

…

kexec_file.c

kexec: derive purgatory entry from symbol

2026-01-31 16:16:07 -08:00

kexec_internal.h

kexec: enable CMA based contiguous allocation

2025-08-02 12:01:38 -07:00

kexec.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

kheaders.c

…

kprobes.c

Convert 'alloc_flex' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

kstack_erase.c

sysctl: remove __user qualifier from stack_erasing_sysctl buffer argument

2025-11-27 15:44:53 +01:00

ksyms_common.c

…

ksysfs.c

kexec: move sysfs entries to /sys/kernel/kexec

2025-11-27 14:24:42 -08:00

kthread.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

latencytop.c

…

Makefile

kcov: Enable context analysis

2026-01-05 16:43:34 +01:00

module_signature.c

…

notifier.c

…

nscommon.c

ns: rename is_initial_namespace()

2025-11-11 10:01:31 +01:00

nsproxy.c

nsproxy: fix free_nsproxy() and simplify create_new_namespaces()

2025-11-14 13:10:38 +01:00

nstree.c

nstree: fix kernel-doc comments for internal functions

2025-11-14 13:10:38 +01:00

padata.c

Convert more 'alloc_obj' cases to default GFP_KERNEL arguments

2026-02-21 20:03:00 -08:00

panic.c

panic: add panic_force_cpu= parameter to redirect panic to a specific CPU

2026-02-03 08:21:26 -08:00

params.c

Convert more 'alloc_obj' cases to default GFP_KERNEL arguments

2026-02-21 20:03:00 -08:00

pid_namespace.c

pid: rely on common reference count behavior

2025-11-11 10:01:32 +01:00

pid_sysctl.h

…

pid.c

Revert "pid: make __task_pid_nr_ns(ns => NULL) safe for zombie callers"

2026-02-10 11:39:30 +01:00

profile.c

…

ptrace.c

rseq: Introduce struct rseq_data

2025-11-04 08:30:50 +01:00

range.c

…

reboot.c

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21 01:02:28 -08:00

regset.c

…

relay.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

resource_kunit.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

resource.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

rseq.c

rseq: Lower default slice extension

2026-01-22 11:11:20 +01:00

scftorture.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

scs.c

scs: fix a wrong parameter in __scs_magic

2025-11-12 10:00:13 -08:00

seccomp.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

signal.c

compiler-context-analysis: Remove __cond_lock() function-like helper

2026-01-05 16:43:33 +01:00

smp.c

smp: Introduce a helper function to check for pending IPIs

2025-11-19 18:06:50 +01:00

smpboot.c

…

smpboot.h

…

softirq.c

softirq: Allow to drop the softirq-BKL lock on PREEMPT_RT

2025-09-17 16:25:41 +02:00

stacktrace.c

…

static_call_inline.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

static_call.c

…

stop_machine.c

…

sys_ni.c

rseq: Implement sys_rseq_slice_yield()

2026-01-22 11:11:17 +01:00

sys.c

Merge tag 'riscv-for-linus-7.0-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

2026-02-12 19:17:44 -08:00

sysctl-test.c

…

sysctl.c

sysctl: replace SYSCTL_INT_CONV_CUSTOM macro with functions

2026-01-06 11:27:10 +01:00

task_work.c

task_work: Fix NMI race condition

2025-10-29 10:29:54 +01:00

taskstats.c

…

torture.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

tracepoint.c

Convert 'alloc_flex' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

tsacct.c

tsacct: skip all kernel threads

2026-01-26 19:07:13 -08:00

ucount.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

uid16.c

…

uid16.h

…

umh.c

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21 01:02:28 -08:00

up.c

…

user_namespace.c

Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses

2026-02-22 08:26:33 -08:00

user-return-notifier.c

…

user.c

ns: drop custom reference count initialization for initial namespaces

2025-11-11 10:01:32 +01:00

utsname_sysctl.c

…

utsname.c

Merge tag 'namespace-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

2025-09-29 11:20:29 -07:00

vhost_task.c

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

vmcore_info.c

Merge tag 'mm-nonmm-stable-2026-02-12-10-48' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-02-12 12:13:01 -08:00

watch_queue.c

Convert 'alloc_flex' family to use the new default GFP_KERNEL argument

2026-02-21 17:09:51 -08:00

watchdog_buddy.c

…

watchdog_perf.c

watchdog/hardlockup: simplify perf event probe and remove per-cpu dependency

2026-02-08 00:13:35 -08:00

watchdog.c

watchdog/softlockup: fix sample ring index wrap in need_counting_irqs()

2026-02-08 00:13:34 -08:00

workqueue_internal.h

…

workqueue.c

workqueue: set WQ_AFFN_CACHE_SHARD as the default affinity scope

2026-04-01 10:24:18 -10:00