[PATCH 00/14] Present useful limits to user (v2)

Topi Miettinen toiwoton at gmail.com
Fri Jul 15 20:35:47 AEST 2016


Hello,

There are many basic ways to control processes, including capabilities,
cgroups and resource limits. However, there are far fewer ways to find out
useful values for the limits, except blind trial and error.

This patch series attempts to fix that by giving at least a nice starting
point from the highwater mark values of the resources in question.
I looked where each limit is checked and added a call to update the mark
nearby.

Example run of program from Documentation/accounting/getdelauys.c:

./getdelays -R -p `pidof smartd`
printing resource accounting
RLIMIT_CPU=0
RLIMIT_FSIZE=0
RLIMIT_DATA=18198528
RLIMIT_STACK=135168
RLIMIT_CORE=0
RLIMIT_RSS=0
RLIMIT_NPROC=1
RLIMIT_NOFILE=55
RLIMIT_MEMLOCK=0
RLIMIT_AS=130879488
RLIMIT_LOCKS=0
RLIMIT_SIGPENDING=0
RLIMIT_MSGQUEUE=0
RLIMIT_NICE=0
RLIMIT_RTPRIO=0
RLIMIT_RTTIME=0

./getdelays -R -C /sys/fs/cgroup/systemd/system.slice/smartd.service/
printing resource accounting
sleeping 1, blocked 0, running 0, stopped 0, uninterruptible 0
RLIMIT_CPU=0
RLIMIT_FSIZE=0
RLIMIT_DATA=18198528
RLIMIT_STACK=135168
RLIMIT_CORE=0
RLIMIT_RSS=0
RLIMIT_NPROC=1
RLIMIT_NOFILE=55
RLIMIT_MEMLOCK=0
RLIMIT_AS=130879488
RLIMIT_LOCKS=0
RLIMIT_SIGPENDING=0
RLIMIT_MSGQUEUE=0
RLIMIT_NICE=0
RLIMIT_RTPRIO=0
RLIMIT_RTTIME=0

In this example, smartd is running as a non-root user. The presented
values can be used as a starting point for giving new limits to the
service.

There's one problem with the patch 07/13, kernel initialization calls
create_worker() which seems to use different locking model or something:

[    0.145410] =========================================================
[    0.148000] [ INFO: possible irq lock inversion dependency detected ]
[    0.148000] 4.7.0-rc7+ #155 Not tainted
[    0.148000] ---------------------------------------------------------
[    0.148000] swapper/0/1 just changed the state of lock:
[    0.148000]  (&(&(&sig->stats_lock)->lock)->rlock){+.....}, at: [<ffffffff810bf769>] __sched_setscheduler+0x339/0xbd0
[    0.148000] but this lock was taken by another, HARDIRQ-safe lock in the past:
[    0.148000]  (&rq->lock){-.....}

and interrupts could create inverse lock ordering between them.

[    0.148000] 
[    0.148000] other info that might help us debug this:
[    0.148000]  Possible interrupt unsafe locking scenario:
[    0.148000] 
[    0.148000]        CPU0                    CPU1
[    0.148000]        ----                    ----
[    0.148000]   lock(&(&(&sig->stats_lock)->lock)->rlock);
[    0.148000]                                local_irq_disable();
[    0.148000]                                lock(&rq->lock);
[    0.148000]                                lock(&(&(&sig->stats_lock)->lock)->rlock);
[    0.148000]   <Interrupt>
[    0.148000]     lock(&rq->lock);
[    0.148000] 
[    0.148000]  *** DEADLOCK ***
[    0.148000] 
[    0.148000] 2 locks held by swapper/0/1:
[    0.148000]  #0:  (cpu_hotplug.lock){.+.+.+}, at: [<ffffffff81092824>] get_online_cpus+0x24/0x70
[    0.148000]  #1:  (smpboot_threads_lock){+.+.+.}, at: [<ffffffff810ba517>] smpboot_register_percpu_thread_cpumask+0x37/0xf0
[    0.148000] 
[    0.148000] the shortest dependencies between 2nd lock and 1st lock:
[    0.148000]  -> (&rq->lock){-.....} ops: 181 {
[    0.148000]     IN-HARDIRQ-W at:
[    0.148000]                       [<ffffffff810e8439>] __lock_acquire+0x6e9/0x1440
[    0.148000]                       [<ffffffff810e95d3>] lock_acquire+0xe3/0x1c0
[    0.148000]                       [<ffffffff818cf661>] _raw_spin_lock+0x31/0x40
[    0.148000]                       [<ffffffff810c3a41>] scheduler_tick+0x41/0xd0
[    0.148000]                       [<ffffffff81110471>] update_process_times+0x51/0x60
[    0.148000]                       [<ffffffff8111fa4f>] tick_periodic+0x2f/0xc0
[    0.148000]                       [<ffffffff8111fb05>] tick_handle_periodic+0x25/0x70
[    0.148000]                       [<ffffffff8101ebf5>] timer_interrupt+0x15/0x20
[    0.148000]                       [<ffffffff810fc731>] handle_irq_event_percpu+0x41/0x320
[    0.148000]                       [<ffffffff810fca49>] handle_irq_event+0x39/0x60
[    0.148000]                       [<ffffffff810ffe08>] handle_level_irq+0x88/0x110
[    0.148000]                       [<ffffffff8101e58a>] handle_irq+0x1a/0x30
[    0.148000]                       [<ffffffff818d2281>] do_IRQ+0x61/0x120
[    0.148000]                       [<ffffffff818d0949>] ret_from_intr+0x0/0x19
[    0.148000]                       [<ffffffff810fe969>] __setup_irq+0x3f9/0x5e0
[    0.148000]                       [<ffffffff810feb96>] setup_irq+0x46/0xa0
[    0.148000]                       [<ffffffff821878e2>] setup_default_timer_irq+0x1e/0x20
[    0.148000]                       [<ffffffff821878fb>] hpet_time_init+0x17/0x19
[    0.148000]                       [<ffffffff821878bd>] x86_late_time_init+0xa/0x11
[    0.148000]                       [<ffffffff82181ef9>] start_kernel+0x39d/0x465
[    0.148000]                       [<ffffffff82181294>] x86_64_start_reservations+0x2f/0x31
[    0.148000]                       [<ffffffff8218140e>] x86_64_start_kernel+0x178/0x18b
[    0.148000]     INITIAL USE at:
[    0.148000]                      [<ffffffff810e7f90>] __lock_acquire+0x240/0x1440
[    0.148000]                      [<ffffffff810e95d3>] lock_acquire+0xe3/0x1c0
[    0.148000]                      [<ffffffff818cf82c>] _raw_spin_lock_irqsave+0x3c/0x50
[    0.148000]                      [<ffffffff810bdc9d>] rq_attach_root+0x1d/0x100
[    0.148000]                      [<ffffffff8219deab>] sched_init+0x2f5/0x44c
[    0.148000]                      [<ffffffff82181d9d>] start_kernel+0x241/0x465
[    0.148000]                      [<ffffffff82181294>] x86_64_start_reservations+0x2f/0x31
[    0.148000]                      [<ffffffff8218140e>] x86_64_start_kernel+0x178/0x18b
[    0.148000]   }
[    0.148000]   ... key      at: [<ffffffff822f3ad0>] __key.60059+0x0/0x8
[    0.148000]   ... acquired at:
[    0.148000]    [<ffffffff810e95d3>] lock_acquire+0xe3/0x1c0
[    0.148000]    [<ffffffff818cf661>] _raw_spin_lock+0x31/0x40
[    0.148000]    [<ffffffff810c0514>] set_user_nice.part.92+0xf4/0x270
[    0.148000]    [<ffffffff810c06b6>] set_user_nice+0x26/0x30
[    0.148000]    [<ffffffff810aee10>] create_worker+0xf0/0x1a0
[    0.148000]    [<ffffffff8219c195>] init_workqueues+0x317/0x51e
[    0.148000]    [<ffffffff81000450>] do_one_initcall+0x50/0x180
[    0.148000]    [<ffffffff821820d2>] kernel_init_freeable+0x111/0x25d
[    0.148000]    [<ffffffff818c206e>] kernel_init+0xe/0x100
[    0.148000]    [<ffffffff818d01ff>] ret_from_fork+0x1f/0x40
[    0.148000] 
[    0.148000] -> (&(&(&sig->stats_lock)->lock)->rlock){+.....} ops: 2 {
[    0.148000]    HARDIRQ-ON-W at:
[    0.148000]                     [<ffffffff810e82e0>] __lock_acquire+0x590/0x1440
[    0.148000]                     [<ffffffff810e95d3>] lock_acquire+0xe3/0x1c0
[    0.148000]                     [<ffffffff818cf661>] _raw_spin_lock+0x31/0x40
[    0.148000]                     [<ffffffff810bf769>] __sched_setscheduler+0x339/0xbd0
[    0.148000]                     [<ffffffff810c0076>] _sched_setscheduler+0x76/0x90
[    0.148000]                     [<ffffffff810c1012>] sched_set_stop_task+0x62/0xb0
[    0.148000]                     [<ffffffff81143983>] cpu_stop_create+0x23/0x30
[    0.148000]                     [<ffffffff810ba48d>] __smpboot_create_thread.part.2+0xad/0x100
[    0.148000]                     [<ffffffff810ba57f>] smpboot_register_percpu_thread_cpumask+0x9f/0xf0
[    0.148000]                     [<ffffffff821a1708>] cpu_stop_init+0x7d/0xb8
[    0.148000]                     [<ffffffff81000450>] do_one_initcall+0x50/0x180
[    0.148000]                     [<ffffffff821820d2>] kernel_init_freeable+0x111/0x25d
[    0.148000]                     [<ffffffff818c206e>] kernel_init+0xe/0x100
[    0.148000]                     [<ffffffff818d01ff>] ret_from_fork+0x1f/0x40
[    0.148000]    INITIAL USE at:
[    0.148000]                    [<ffffffff810e7f90>] __lock_acquire+0x240/0x1440
[    0.148000]                    [<ffffffff810e95d3>] lock_acquire+0xe3/0x1c0
[    0.148000]                    [<ffffffff818cf661>] _raw_spin_lock+0x31/0x40
[    0.148000]                    [<ffffffff810c0514>] set_user_nice.part.92+0xf4/0x270
[    0.148000]                    [<ffffffff810c06b6>] set_user_nice+0x26/0x30
[    0.148000]                    [<ffffffff810aee10>] create_worker+0xf0/0x1a0
[    0.148000]                    [<ffffffff8219c195>] init_workqueues+0x317/0x51e
[    0.148000]                    [<ffffffff81000450>] do_one_initcall+0x50/0x180
[    0.148000]                    [<ffffffff821820d2>] kernel_init_freeable+0x111/0x25d
[    0.148000]                    [<ffffffff818c206e>] kernel_init+0xe/0x100
[    0.148000]                    [<ffffffff818d01ff>] ret_from_fork+0x1f/0x40
[    0.148000]  }
[    0.148000]  ... key      at: [<ffffffff822f2190>] __key.55894+0x0/0x8
[    0.148000]  ... acquired at:
[    0.148000]    [<ffffffff810e6885>] check_usage_backwards+0x155/0x160
[    0.148000]    [<ffffffff810e7533>] mark_lock+0x333/0x610
[    0.148000]    [<ffffffff810e82e0>] __lock_acquire+0x590/0x1440
[    0.148000]    [<ffffffff810e95d3>] lock_acquire+0xe3/0x1c0
[    0.148000]    [<ffffffff818cf661>] _raw_spin_lock+0x31/0x40
[    0.148000]    [<ffffffff810bf769>] __sched_setscheduler+0x339/0xbd0
[    0.148000]    [<ffffffff810c0076>] _sched_setscheduler+0x76/0x90
[    0.148000]    [<ffffffff810c1012>] sched_set_stop_task+0x62/0xb0
[    0.148000]    [<ffffffff81143983>] cpu_stop_create+0x23/0x30
[    0.148000]    [<ffffffff810ba48d>] __smpboot_create_thread.part.2+0xad/0x100
[    0.148000]    [<ffffffff810ba57f>] smpboot_register_percpu_thread_cpumask+0x9f/0xf0
[    0.148000]    [<ffffffff821a1708>] cpu_stop_init+0x7d/0xb8
[    0.148000]    [<ffffffff81000450>] do_one_initcall+0x50/0x180
[    0.148000]    [<ffffffff821820d2>] kernel_init_freeable+0x111/0x25d
[    0.148000]    [<ffffffff818c206e>] kernel_init+0xe/0x100
[    0.148000]    [<ffffffff818d01ff>] ret_from_fork+0x1f/0x40
[    0.148000] 
[    0.148000] 
[    0.148000] stack backtrace:
[    0.148000] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.7.0-rc7+ #155
[    0.148000] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014
[    0.148000]  0000000000000086 00000000aea03eae ffff88003de6ba60 ffffffff813cb2d5
[    0.148000]  ffffffff82d48e60 ffff88003de6bac0 ffff88003de6baa0 ffffffff811a6b05
[    0.148000]  ffff88003de647d8 ffff88003de647d8 ffff88003de64040 ffffffff81d531a7
[    0.148000] Call Trace:
[    0.148000]  [<ffffffff813cb2d5>] dump_stack+0x67/0x92
[    0.148000]  [<ffffffff811a6b05>] print_irq_inversion_bug.part.38+0x1a4/0x1b0
[    0.148000]  [<ffffffff810e6885>] check_usage_backwards+0x155/0x160
[    0.148000]  [<ffffffff810e7533>] mark_lock+0x333/0x610
[    0.148000]  [<ffffffff810e6730>] ? check_usage_forwards+0x160/0x160
[    0.148000]  [<ffffffff810e82e0>] __lock_acquire+0x590/0x1440
[    0.148000]  [<ffffffff810e7a6d>] ? trace_hardirqs_on+0xd/0x10
[    0.148000]  [<ffffffff81104aad>] ? debug_lockdep_rcu_enabled+0x1d/0x20
[    0.148000]  [<ffffffff810e95d3>] lock_acquire+0xe3/0x1c0
[    0.148000]  [<ffffffff810bf769>] ? __sched_setscheduler+0x339/0xbd0
[    0.148000]  [<ffffffff818cf661>] _raw_spin_lock+0x31/0x40
[    0.148000]  [<ffffffff810bf769>] ? __sched_setscheduler+0x339/0xbd0
[    0.148000]  [<ffffffff810bf769>] __sched_setscheduler+0x339/0xbd0
[    0.148000]  [<ffffffff810c0076>] _sched_setscheduler+0x76/0x90
[    0.148000]  [<ffffffff810c1012>] sched_set_stop_task+0x62/0xb0
[    0.148000]  [<ffffffff81143983>] cpu_stop_create+0x23/0x30
[    0.148000]  [<ffffffff810ba48d>] __smpboot_create_thread.part.2+0xad/0x100
[    0.148000]  [<ffffffff810ba57f>] smpboot_register_percpu_thread_cpumask+0x9f/0xf0
[    0.148000]  [<ffffffff821a1708>] cpu_stop_init+0x7d/0xb8
[    0.148000]  [<ffffffff821a168b>] ? pid_namespaces_init+0x40/0x40
[    0.148000]  [<ffffffff81000450>] do_one_initcall+0x50/0x180
[    0.148000]  [<ffffffff8102c24d>] ? print_cpu_info+0x7d/0xe0
[    0.148000]  [<ffffffff821820d2>] kernel_init_freeable+0x111/0x25d
[    0.148000]  [<ffffffff818c206e>] kernel_init+0xe/0x100
[    0.148000]  [<ffffffff818d01ff>] ret_from_fork+0x1f/0x40
[    0.148000]  [<ffffffff818c2060>] ? rest_init+0x130/0x130

In this v2, I tried to address all comments, thanks for reviews.

-Topi

Topi Miettinen (14):
  resource limits: foundation for resource highwater tracking
  resource limits: aggregate task highwater marks to cgroup level
  resource limits: track highwater mark of file sizes
  resource limits: track highwater mark of VM data segment
  resource limits: track highwater mark of stack size
  resource limits: track highwater mark of cores dumped
  resource limits: track highwater mark of user processes
  resource limits: track highwater mark of number of files
  resource limits: track highwater mark of locked memory
  resource limits: track highwater mark of address space size
  resource limits: track highwater mark of number of pending signals
  resource limits: track highwater mark of size of message queues
  resource limits: track highwater mark of niceness
  resource limits: track highwater mark of RT priority

 Documentation/accounting/getdelays.c       | 62 ++++++++++++++++++++++--
 arch/ia64/kernel/perfmon.c                 |  1 +
 arch/powerpc/kvm/book3s_64_vio.c           |  2 +
 arch/powerpc/mm/mmu_context_iommu.c        |  2 +
 arch/x86/ia32/ia32_aout.c                  |  2 +
 drivers/infiniband/core/umem.c             |  1 +
 drivers/infiniband/hw/hfi1/user_pages.c    |  2 +
 drivers/infiniband/hw/qib/qib_user_pages.c |  2 +
 drivers/infiniband/hw/usnic/usnic_uiom.c   |  2 +
 drivers/misc/mic/scif/scif_rma.c           |  1 +
 drivers/vfio/vfio_iommu_spapr_tce.c        |  2 +
 drivers/vfio/vfio_iommu_type1.c            |  5 ++
 fs/attr.c                                  |  2 +
 fs/binfmt_aout.c                           |  2 +
 fs/binfmt_flat.c                           |  2 +
 fs/coredump.c                              | 11 +++--
 fs/file.c                                  |  4 ++
 include/linux/cgroup-defs.h                |  5 ++
 include/linux/sched.h                      | 61 +++++++++++++++++++++++
 include/linux/tsacct_kern.h                |  3 ++
 include/uapi/linux/cgroupstats.h           |  3 ++
 include/uapi/linux/taskstats.h             | 10 +++-
 ipc/mqueue.c                               |  1 +
 kernel/bpf/syscall.c                       |  8 +++
 kernel/cgroup.c                            | 78 ++++++++++++++++++++++++++++++
 kernel/cred.c                              |  1 +
 kernel/events/core.c                       |  1 +
 kernel/fork.c                              |  2 +
 kernel/sched/core.c                        |  6 +++
 kernel/signal.c                            |  2 +
 kernel/sys.c                               |  5 ++
 kernel/taskstats.c                         |  4 ++
 kernel/tsacct.c                            | 47 ++++++++++++++++++
 mm/mlock.c                                 |  8 +++
 mm/mmap.c                                  | 17 ++++++-
 mm/mremap.c                                |  7 +++
 36 files changed, 365 insertions(+), 9 deletions(-)

-- 
2.8.1



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