Xuewei Zhang
4929a4e6fa
sched/fair: Scale bandwidth quota and period without losing quota/period ratio precision ...
The quota/period ratio is used to ensure a child task group won't get
more bandwidth than the parent task group, and is calculated as:
normalized_cfs_quota() = [(quota_us << 20) / period_us]
If the quota/period ratio was changed during this scaling due to
precision loss, it will cause inconsistency between parent and child
task groups.
See below example:
A userspace container manager (kubelet) does three operations:
1) Create a parent cgroup, set quota to 1,000us and period to 10,000us.
2) Create a few children cgroups.
3) Set quota to 1,000us and period to 10,000us on a child cgroup.
These operations are expected to succeed. However, if the scaling of
147/128 happens before step 3, quota and period of the parent cgroup
will be changed:
new_quota: 1148437ns, 1148us
new_period: 11484375ns, 11484us
And when step 3 comes in, the ratio of the child cgroup will be
104857, which will be larger than the parent cgroup ratio (104821),
and will fail.
Scaling them by a factor of 2 will fix the problem.
Tested-by: Phil Auld <pauld@redhat.com>
Signed-off-by: Xuewei Zhang <xueweiz@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Phil Auld <pauld@redhat.com>
Cc: Anton Blanchard <anton@ozlabs.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Fixes: 2e8e192263https://lkml.kernel.org/r/20191004001243.140897-1-xueweiz@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-10-09 12:38:02 +02:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
2019-09-28 17:47:33 -07:00
Merge branch 'for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
2019-09-17 15:57:22 -07:00
kgdb: don't use a notifier to enter kgdb at panic; call directly
2019-09-25 17:51:40 -07:00
powerpc updates for 5.4
2019-09-20 11:48:06 -07:00
Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
2019-09-28 08:14:15 -07:00
um: Enable CONFIG_CONSTRUCTORS
2019-09-15 21:37:13 +02:00
Power management updates for 5.4-rc1
2019-09-17 19:15:14 -07:00
livepatch: Nullify obj->mod in klp_module_coming()'s error path
2019-08-19 13:03:37 +02:00
Revert "locking/pvqspinlock: Don't wait if vCPU is preempted"
2019-09-25 10:22:37 +02:00
Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
2019-09-28 08:14:15 -07:00
Merge branch 'for-5.4' into for-linus
2019-09-16 12:54:25 +02:00
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-09-16 17:25:49 -07:00
sched/fair: Scale bandwidth quota and period without losing quota/period ratio precision
2019-10-09 12:38:02 +02:00
Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-09-26 15:53:17 -07:00
A few more tracing fixes:
2019-09-30 09:29:53 -07:00
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
audit/stable-5.3 PR 20190702
2019-07-08 18:55:42 -07:00
audit/stable-5.3 PR 20190702
2019-07-08 18:55:42 -07:00
audit/stable-5.3 PR 20190702
2019-07-08 18:55:42 -07:00
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
2019-06-19 17:09:55 +02:00
kernel/configs: Replace GPL boilerplate code with SPDX identifier
2019-07-30 18:34:15 +02:00
cpu/SMT: create and export cpu_smt_possible()
2019-09-24 13:37:28 +02:00
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 230
2019-06-19 17:09:06 +02:00
Merge branch 'access-creds'
2019-07-25 08:36:29 -07:00
kernel/elfcore.c: include proper prototypes
2019-09-25 17:51:39 -07:00
tasks, sched/core: With a grace period after finish_task_switch(), remove unnecessary code
2019-09-25 17:42:29 +02:00
extable: Add function to search only kernel exception table
2019-08-21 22:23:48 +10:00
Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-09-28 12:39:07 -07:00
hrtimer/treewide: Use hrtimer_sleeper_start_expires()
2019-08-01 17:43:16 +02:00
kheaders: include only headers into kheaders_data.tar.xz
2019-07-09 10:10:52 +09:00
mm/nvdimm: add is_ioremap_addr and use that to check ioremap address
2019-07-12 11:05:40 -07:00
jump_label: Don't warn on __exit jump entries
2019-08-29 15:10:10 +01:00
kallsyms: Don't let kallsyms_lookup_size_offset() fail on retrieving the first symbol
2019-08-27 16:19:56 +01:00
sched/rt, Kconfig: Unbreak def/oldconfig with CONFIG_PREEMPT=y
2019-07-22 18:05:11 +02:00
kexec_load: Disable at runtime if the kernel is locked down
2019-08-19 21:54:15 -07:00
kexec: bail out upon SIGKILL when allocating memory.
2019-09-25 17:51:40 -07:00
kexec_elf: support 32 bit ELF files
2019-09-06 23:58:44 +02:00
Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
2019-09-28 08:14:15 -07:00
Tracing updates:
2019-09-20 11:19:48 -07:00
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
2019-09-27 19:37:27 -07:00
Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
2019-09-28 08:14:15 -07:00
MODSIGN: Export module signature definitions
2019-08-05 18:39:56 -04:00
MODSIGN: Export module signature definitions
2019-08-05 18:39:56 -04:00
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
padata: remove cpu_index from the parallel_queue
2019-09-13 21:15:41 +10:00
bug: consolidate __WARN_FLAGS usage
2019-09-25 17:51:41 -07:00
lockdown: Lock down module params that specify hardware parameters (eg. ioport)
2019-08-19 21:54:16 -07:00
kernel/pid.c: convert struct pid count to refcount_t
2019-07-16 19:23:24 -07:00
proc/sysctl: add shared variables for range check
2019-07-18 17:08:07 -07:00
ptrace: add PTRACE_GET_SYSCALL_INFO request
2019-07-16 19:23:24 -07:00
mm/memory_hotplug.c: use PFN_UP / PFN_DOWN in walk_system_ram_range()
2019-09-24 15:54:09 -07:00
core-process-v5.4
2019-09-16 09:28:19 -07:00
smp: Warn on function calls from softirq context
2019-07-20 11:27:16 +02:00
Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-07-08 11:01:13 -07:00
stacktrace: Constify 'entries' arguments
2019-07-25 15:43:26 +02:00
stop_machine: Fix stop_cpus_in_progress ordering
2019-08-08 09:09:30 +02:00
Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2019-09-17 12:35:15 -07:00
arch: handle arches who do not yet define clone3
2019-06-21 01:54:53 +02:00
arm64, mm: move generic mmap layout functions to mm
2019-09-24 15:54:11 -07:00
torture: Remove exporting of internal functions
2019-08-01 14:30:22 -07:00
The main changes in this release include:
2019-07-18 11:51:00 -07:00
proc/sysctl: add shared variables for range check
2019-07-18 17:08:07 -07:00
smp: Remove smp_call_function() and on_each_cpu() return values
2019-06-23 14:26:26 +02:00
Keyrings namespacing
2019-07-08 19:36:47 -07:00
Keyrings namespacing
2019-07-08 19:36:47 -07:00
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441
2019-06-05 17:37:17 +02:00
watchdog: Mark watchdog_hrtimer to expire in hard interrupt context
2019-08-01 20:51:20 +02:00
workqueue: require CPU hotplug read exclusion for apply_workqueue_attrs
2019-09-13 21:15:40 +10:00
4929a4e6fa