linux/kernel
Gregory Price 7d709f49ba vmscan,cgroup: apply mems_effective to reclaim
It is possible for a reclaimer to cause demotions of an lruvec belonging
to a cgroup with cpuset.mems set to exclude some nodes.  Attempt to apply
this limitation based on the lruvec's memcg and prevent demotion.

Notably, this may still allow demotion of shared libraries or any memory
first instantiated in another cgroup.  This means cpusets still cannot
cannot guarantee complete isolation when demotion is enabled, and the docs
have been updated to reflect this.

This is useful for isolating workloads on a multi-tenant system from
certain classes of memory more consistently - with the noted exceptions.

Note on locking:

The cgroup_get_e_css reference protects the css->effective_mems, and calls
of this interface would be subject to the same race conditions associated
with a non-atomic access to cs->effective_mems.

So while this interface cannot make strong guarantees of correctness, it
can therefore avoid taking a global or rcu_read_lock for performance.

Link: https://lkml.kernel.org/r/20250424202806.52632-3-gourry@gourry.net
Signed-off-by: Gregory Price <gourry@gourry.net>
Suggested-by: Shakeel Butt <shakeel.butt@linux.dev>
Suggested-by: Waiman Long <longman@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev>
Reviewed-by: Waiman Long <longman@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Koutný <mkoutny@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-12 23:50:33 -07:00
..
bpf bpf: Add namespace to BPF internal symbols 2025-04-25 09:21:23 -07:00
cgroup vmscan,cgroup: apply mems_effective to reclaim 2025-05-12 23:50:33 -07:00
configs - The 6 patch series "Enable strict percpu address space checks" from 2025-04-01 09:29:18 -07:00
debug TTY/Serial driver updates for 6.15-rc1 2025-04-02 18:17:33 -07:00
dma dma-coherent: Warn if OF reserved memory is beyond current coherent DMA mask 2025-04-22 17:44:09 +02:00
entry Objtool changes for v6.15: 2025-03-24 21:18:05 -07:00
events kernel/events/uprobes: uprobe_write_opcode() rewrite 2025-05-11 17:48:18 -07:00
futex futex: Use a hashmask instead of hashsize 2025-02-26 16:07:59 +01:00
gcov gcov: clang: use correct function param names 2025-01-24 22:47:27 -08:00
irq genirq/msi: Prevent NULL pointer dereference in msi_domain_debug_show() 2025-04-30 23:25:10 +02:00
kcsan treewide: Switch/rename to timer_delete[_sync]() 2025-04-05 10:30:12 +02:00
livepatch Modules changes for 6.15-rc1 2025-03-30 15:44:36 -07:00
locking - The 7 patch series "powerpc/crash: use generic crashkernel 2025-04-01 10:06:52 -07:00
module ring-buffer updates for v6.15 2025-03-31 13:37:22 -07:00
power This update includes the following changes: 2025-03-29 10:01:55 -07:00
printk printk changes for 6.15 2025-03-27 19:22:24 -07:00
rcu treewide: Switch/rename to timer_delete[_sync]() 2025-04-05 10:30:12 +02:00
sched Fix sporadic crashes in dequeue_entities() due to ... bad math. 2025-04-26 09:23:20 -07:00
time timekeeping: Prevent coarse clocks going backwards 2025-04-28 11:17:29 +02:00
trace tracing: Do not take trace_event_sem in print_event_fields() 2025-05-01 22:44:52 -04:00
.gitignore
acct.c acct: block access to kernel internal filesystems 2025-02-12 12:24:16 +01:00
async.c
audit.c audit: Initialize lsmctx to avoid memory allocation error 2025-01-29 20:02:04 -05:00
audit.h audit: change context data from secid to lsm_prop 2024-10-11 14:34:16 -04:00
audit_fsnotify.c
audit_tree.c
audit_watch.c fs: add kern_path_locked_negative() 2025-04-15 11:32:34 +02:00
auditfilter.c audit: fix suffixed '/' filename matching 2024-12-05 19:22:38 -05:00
auditsc.c fs: dedup handling of struct filename init and refcounts bumps 2025-03-18 15:34:27 +01:00
backtracetest.c backtracetest: add MODULE_DESCRIPTION() 2024-06-24 22:24:55 -07:00
bounds.c
capability.c capability: Remove unused has_capability 2025-03-07 22:03:09 -06:00
cfi.c Modules changes for 6.15-rc1 2025-03-30 15:44:36 -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.c hyperv-next for 6.15 2025-03-25 14:47:04 -07:00
cpu_pm.c
crash_core.c crash: Use note name macros 2025-02-10 16:56:58 -08:00
crash_reserve.c crash: remove an unused argument from reserve_crashkernel_generic() 2025-03-16 22:30:47 -07:00
cred.c cred: remove old {override,revert}_creds() helpers 2024-12-02 11:25:09 +01:00
delayacct.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
dma.c
elfcorehdr.c
exec_domain.c
exit.c exit: fix the usage of delay_group_leader->exit_code in do_notify_parent() and pidfs_exit() 2025-03-25 15:56:22 +01:00
exit.h
extable.c
fail_function.c
fork.c kernel/fork: only call untrack_pfn_clear() on VMAs duplicated for fork() 2025-05-11 17:26:06 -07:00
freezer.c sched/fair: Fix external p->on_rq users 2024-10-14 09:14:35 +02:00
gen_kheaders.sh Revert "kheaders: Ignore silly-rename files" 2025-03-15 21:22:52 +09:00
groups.c
hung_task.c hung_task: show the blocker task if the task is hung on mutex 2025-03-21 22:10:04 -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.c kallsyms: Remove KALLSYMS_ABSOLUTE_PERCPU 2025-02-18 10:16:04 +01:00
kallsyms_internal.h kallsyms: get rid of code for absolute kallsyms 2024-07-20 16:33:21 +09:00
kallsyms_selftest.c kallsyms: Use kthread_run_on_cpu() 2025-01-02 22:12:12 +01:00
kallsyms_selftest.h
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 crash, powerpc: default to CRASH_DUMP=n on PPC_BOOK3S_32 2024-11-14 22:43:48 -08:00
Kconfig.locks
Kconfig.preempt sched: No PREEMPT_RT=y for all{yes,mod}config 2024-11-07 15:25:05 +01:00
kcov.c kcov: mark in_softirq_really() as __always_inline 2024-12-30 17:59:08 -08:00
kexec.c
kexec_core.c - The 7 patch series "powerpc/crash: use generic crashkernel 2025-04-01 10:06:52 -07:00
kexec_elf.c kexec: initialize ELF lowest address to ULONG_MAX 2025-03-16 22:30:47 -07:00
kexec_file.c crash: let arch decide usable memory range in reserved area 2025-03-16 22:30:47 -07:00
kexec_internal.h kexec: use atomic_try_cmpxchg_acquire() in kexec_trylock() 2024-09-01 20:43:23 -07:00
kheaders.c kheaders: Simplify attribute through __BIN_ATTR_SIMPLE_RO() 2024-12-24 09:46:49 +01:00
kprobes.c kprobes: Use RCU in all users of __module_text_address(). 2025-03-10 11:54:46 +01:00
ksyms_common.c
ksysfs.c kernel/ksysfs.c: simplify bin_attribute definition 2025-01-07 16:59:15 +01:00
kthread.c treewide: Switch/rename to timer_delete[_sync]() 2025-04-05 10:30:12 +02:00
latencytop.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
Makefile tracing: Disable branch profiling in noinstr code 2025-03-22 09:49:26 +01:00
module_signature.c
notifier.c reboot: move reboot_notifier_list to kernel/reboot.c 2024-11-05 17:12:31 -08:00
nsproxy.c fdget(), trivial conversions 2024-11-03 01:28:06 -05:00
padata.c padata: switch padata_find_next() to using cpumask_next_wrap() 2025-02-24 16:37:23 -05:00
panic.c These are objtool fixes and updates by Josh Poimboeuf, centered 2025-04-02 10:30:10 -07:00
params.c module: ensure that kobject_put() is safe for module type kobjects 2025-05-07 20:24:59 +02:00
pid.c kernel-6.15-rc1.tasklist_lock 2025-03-24 13:39:27 -07:00
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
profile.c profiling: remove profile=sleep support 2024-08-04 13:36:28 -07:00
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 relay: use kasprintf() instead of fixed buffer formatting 2025-03-21 22:10:05 -07:00
resource.c resource: replace open coded variant of DEFINE_RES() 2025-03-21 22:10:05 -07:00
resource_kunit.c resource, kunit: fix user-after-free in resource_test_region_intersects() 2024-10-09 12:47:19 -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 scftorture: Handle NULL argument passed to scf_add_to_free_list(). 2024-11-14 16:09:51 -08:00
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 vfs-6.15-rc1.fixes 2025-04-02 16:05:21 -07:00
smp.c CSD-lock pull request for v6.14 2025-01-28 11:34:03 -08:00
smpboot.c
smpboot.h
softirq.c lockdep: Fix wait context check on softirq for PREEMPT_RT 2025-03-25 10:46:44 +01:00
stackleak.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
stacktrace.c
static_call.c
static_call_inline.c Modules changes for 6.15-rc1 2025-03-30 15:44:36 -07:00
stop_machine.c stop-machine: Add comment for rcu_momentary_eqs() 2025-03-11 10:15:52 -07:00
sys.c Updates for the core time/timer subsystem: 2025-03-25 10:33:23 -07:00
sys_ni.c Probes updates for v6.11: 2024-07-18 12:19:20 -07:00
sysctl-test.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
sysctl.c s390 updates for 6.15 merge window 2025-03-29 11:59:43 -07:00
task_work.c kasan: make kasan_record_aux_stack_noalloc() the default behaviour 2025-01-13 22:40:36 -08:00
taskstats.c fdget(), more trivial conversions 2024-11-03 01:28:06 -05:00
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 tsacct: replace strncpy() with strscpy() 2024-07-12 16:39:53 -07:00
ucount.c ucount: use rcuref_t for reference counting 2025-03-16 22:30:50 -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-return-notifier.c
user.c uidgid: make sure we fit into one cacheline 2024-09-12 12:16:09 +02:00
user_namespace.c uidgid: add map_id_range_up() 2025-02-12 12:12:27 +01:00
usermode_driver.c
utsname.c
utsname_sysctl.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
vhost_task.c vhost_task: fix vhost_task_create() documentation 2025-04-18 10:08:11 -04:00
vmcore_info.c mm: support only one page_type per page 2024-09-03 21:15:43 -07:00
watch_queue.c vfs-6.15-rc1.pipe 2025-03-24 09:52:37 -07:00
watchdog.c A treewide hrtimer timer cleanup 2025-03-25 10:54:15 -07:00
watchdog_buddy.c
watchdog_perf.c - The 7 patch series "powerpc/crash: use generic crashkernel 2025-04-01 10:06:52 -07:00
workqueue.c treewide: Switch/rename to timer_delete[_sync]() 2025-04-05 10:30:12 +02:00
workqueue_internal.h