Commit Graph

263 Commits

Author SHA1 Message Date
Linus Torvalds 3ee8d6c592 Merge branch 'for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
 "Three minor cleanup patches"

* 'for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  Use kvmalloc in cgroups-v1
  cgroup: minor tweak for logic to get cgroup css
  cgroup: Replace a seq_printf() call by seq_puts() in cgroup_print_ss_mask()
2019-09-17 15:57:22 -07:00
Linus Torvalds 7e67a85999 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:

 - MAINTAINERS: Add Mark Rutland as perf submaintainer, Juri Lelli and
   Vincent Guittot as scheduler submaintainers. Add Dietmar Eggemann,
   Steven Rostedt, Ben Segall and Mel Gorman as scheduler reviewers.

   As perf and the scheduler is getting bigger and more complex,
   document the status quo of current responsibilities and interests,
   and spread the review pain^H^H^H^H fun via an increase in the Cc:
   linecount generated by scripts/get_maintainer.pl. :-)

 - Add another series of patches that brings the -rt (PREEMPT_RT) tree
   closer to mainline: split the monolithic CONFIG_PREEMPT dependencies
   into a new CONFIG_PREEMPTION category that will allow the eventual
   introduction of CONFIG_PREEMPT_RT. Still a few more hundred patches
   to go though.

 - Extend the CPU cgroup controller with uclamp.min and uclamp.max to
   allow the finer shaping of CPU bandwidth usage.

 - Micro-optimize energy-aware wake-ups from O(CPUS^2) to O(CPUS).

 - Improve the behavior of high CPU count, high thread count
   applications running under cpu.cfs_quota_us constraints.

 - Improve balancing with SCHED_IDLE (SCHED_BATCH) tasks present.

 - Improve CPU isolation housekeeping CPU allocation NUMA locality.

 - Fix deadline scheduler bandwidth calculations and logic when cpusets
   rebuilds the topology, or when it gets deadline-throttled while it's
   being offlined.

 - Convert the cpuset_mutex to percpu_rwsem, to allow it to be used from
   setscheduler() system calls without creating global serialization.
   Add new synchronization between cpuset topology-changing events and
   the deadline acceptance tests in setscheduler(), which were broken
   before.

 - Rework the active_mm state machine to be less confusing and more
   optimal.

 - Rework (simplify) the pick_next_task() slowpath.

 - Improve load-balancing on AMD EPYC systems.

 - ... and misc cleanups, smaller fixes and improvements - please see
   the Git log for more details.

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
  sched/psi: Correct overly pessimistic size calculation
  sched/fair: Speed-up energy-aware wake-ups
  sched/uclamp: Always use 'enum uclamp_id' for clamp_id values
  sched/uclamp: Update CPU's refcount on TG's clamp changes
  sched/uclamp: Use TG's clamps to restrict TASK's clamps
  sched/uclamp: Propagate system defaults to the root group
  sched/uclamp: Propagate parent clamps
  sched/uclamp: Extend CPU's cgroup controller
  sched/topology: Improve load balancing on AMD EPYC systems
  arch, ia64: Make NUMA select SMP
  sched, perf: MAINTAINERS update, add submaintainers and reviewers
  sched/fair: Use rq_lock/unlock in online_fair_sched_group
  cpufreq: schedutil: fix equation in comment
  sched: Rework pick_next_task() slow-path
  sched: Allow put_prev_task() to drop rq->lock
  sched/fair: Expose newidle_balance()
  sched: Add task_struct pointer to sched_class::set_curr_task
  sched: Rework CPU hotplug task selection
  sched/{rt,deadline}: Fix set_next_task vs pick_next_task
  sched: Fix kerneldoc comment for ia64_set_curr_task
  ...
2019-09-16 17:25:49 -07:00
Roman Gushchin 97a6136983 cgroup: freezer: fix frozen state inheritance
If a new child cgroup is created in the frozen cgroup hierarchy
(one or more of ancestor cgroups is frozen), the CGRP_FREEZE cgroup
flag should be set. Otherwise if a process will be attached to the
child cgroup, it won't become frozen.

The problem can be reproduced with the test_cgfreezer_mkdir test.

This is the output before this patch:
  ~/test_freezer
  ok 1 test_cgfreezer_simple
  ok 2 test_cgfreezer_tree
  ok 3 test_cgfreezer_forkbomb
  Cgroup /sys/fs/cgroup/cg_test_mkdir_A/cg_test_mkdir_B isn't frozen
  not ok 4 test_cgfreezer_mkdir
  ok 5 test_cgfreezer_rmdir
  ok 6 test_cgfreezer_migrate
  ok 7 test_cgfreezer_ptrace
  ok 8 test_cgfreezer_stopped
  ok 9 test_cgfreezer_ptraced
  ok 10 test_cgfreezer_vfork

And with this patch:
  ~/test_freezer
  ok 1 test_cgfreezer_simple
  ok 2 test_cgfreezer_tree
  ok 3 test_cgfreezer_forkbomb
  ok 4 test_cgfreezer_mkdir
  ok 5 test_cgfreezer_rmdir
  ok 6 test_cgfreezer_migrate
  ok 7 test_cgfreezer_ptrace
  ok 8 test_cgfreezer_stopped
  ok 9 test_cgfreezer_ptraced
  ok 10 test_cgfreezer_vfork

Reported-by: Mark Crossen <mcrossen@fb.com>
Signed-off-by: Roman Gushchin <guro@fb.com>
Fixes: 76f969e894 ("cgroup: cgroup v2 freezer")
Cc: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Tejun Heo <tj@kernel.org>
2019-09-12 14:04:45 -07:00
Marc Koderer 653a23ca7e Use kvmalloc in cgroups-v1
Instead of using its own logic for k-/vmalloc rely on
kvmalloc which is actually doing quite the same.

Signed-off-by: Marc Koderer <marc@koderer.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2019-08-07 11:37:58 -07:00
Juri Lelli 710da3c8ea sched/core: Prevent race condition between cpuset and __sched_setscheduler()
No synchronisation mechanism exists between the cpuset subsystem and
calls to function __sched_setscheduler(). As such, it is possible that
new root domains are created on the cpuset side while a deadline
acceptance test is carried out in __sched_setscheduler(), leading to a
potential oversell of CPU bandwidth.

Grab cpuset_rwsem read lock from core scheduler, so to prevent
situations such as the one described above from happening.

The only exception is normalize_rt_tasks() which needs to work under
tasklist_lock and can't therefore grab cpuset_rwsem. We are fine with
this, as this function is only called by sysrq and, if that gets
triggered, DEADLINE guarantees are already gone out of the window
anyway.

Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bristot@redhat.com
Cc: claudio@evidence.eu.com
Cc: lizefan@huawei.com
Cc: longman@redhat.com
Cc: luca.abeni@santannapisa.it
Cc: mathieu.poirier@linaro.org
Cc: rostedt@goodmis.org
Cc: tj@kernel.org
Cc: tommaso.cucinotta@santannapisa.it
Link: https://lkml.kernel.org/r/20190719140000.31694-9-juri.lelli@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-25 15:55:04 +02:00
Juri Lelli d74b27d63a cgroup/cpuset: Change cpuset_rwsem and hotplug lock order
cpuset_rwsem is going to be acquired from sched_setscheduler() with a
following patch. There are however paths (e.g., spawn_ksoftirqd) in
which sched_scheduler() is eventually called while holding hotplug lock;
this creates a dependecy between hotplug lock (to be always acquired
first) and cpuset_rwsem (to be always acquired after hotplug lock).

Fix paths which currently take the two locks in the wrong order (after
a following patch is applied).

Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bristot@redhat.com
Cc: claudio@evidence.eu.com
Cc: lizefan@huawei.com
Cc: longman@redhat.com
Cc: luca.abeni@santannapisa.it
Cc: mathieu.poirier@linaro.org
Cc: rostedt@goodmis.org
Cc: tj@kernel.org
Cc: tommaso.cucinotta@santannapisa.it
Link: https://lkml.kernel.org/r/20190719140000.31694-7-juri.lelli@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-25 15:55:03 +02:00
Juri Lelli 1243dc518c cgroup/cpuset: Convert cpuset_mutex to percpu_rwsem
Holding cpuset_mutex means that cpusets are stable (only the holder can
make changes) and this is required for fixing a synchronization issue
between cpusets and scheduler core.  However, grabbing cpuset_mutex from
setscheduler() hotpath (as implemented in a later patch) is a no-go, as
it would create a bottleneck for tasks concurrently calling
setscheduler().

Convert cpuset_mutex to be a percpu_rwsem (cpuset_rwsem), so that
setscheduler() will then be able to read lock it and avoid concurrency
issues.

Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bristot@redhat.com
Cc: claudio@evidence.eu.com
Cc: lizefan@huawei.com
Cc: longman@redhat.com
Cc: luca.abeni@santannapisa.it
Cc: mathieu.poirier@linaro.org
Cc: rostedt@goodmis.org
Cc: tj@kernel.org
Cc: tommaso.cucinotta@santannapisa.it
Link: https://lkml.kernel.org/r/20190719140000.31694-6-juri.lelli@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-25 15:55:02 +02:00
Mathieu Poirier f9a25f776d cpusets: Rebuild root domain deadline accounting information
When the topology of root domains is modified by CPUset or CPUhotplug
operations information about the current deadline bandwidth held in the
root domain is lost.

This patch addresses the issue by recalculating the lost deadline
bandwidth information by circling through the deadline tasks held in
CPUsets and adding their current load to the root domain they are
associated with.

Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
[ Various additional modifications. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bristot@redhat.com
Cc: claudio@evidence.eu.com
Cc: lizefan@huawei.com
Cc: longman@redhat.com
Cc: luca.abeni@santannapisa.it
Cc: rostedt@goodmis.org
Cc: tj@kernel.org
Cc: tommaso.cucinotta@santannapisa.it
Link: https://lkml.kernel.org/r/20190719140000.31694-4-juri.lelli@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-25 15:55:01 +02:00
Peng Wang a581563f1b cgroup: minor tweak for logic to get cgroup css
We could only handle the case that css exists
and css_try_get_online() fails.

Signed-off-by: Peng Wang <rocking@whu.edu.cn>
Signed-off-by: Tejun Heo <tj@kernel.org>
2019-07-23 15:46:33 -07:00
Markus Elfring 85db002337 cgroup: Replace a seq_printf() call by seq_puts() in cgroup_print_ss_mask()
A string which did not contain a data format specification should be put
into a sequence. Thus use the corresponding function “seq_puts”.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Tejun Heo <tj@kernel.org>
2019-07-23 15:44:00 -07:00
Linus Torvalds 933a90bf4f Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs mount updates from Al Viro:
 "The first part of mount updates.

  Convert filesystems to use the new mount API"

* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  mnt_init(): call shmem_init() unconditionally
  constify ksys_mount() string arguments
  don't bother with registering rootfs
  init_rootfs(): don't bother with init_ramfs_fs()
  vfs: Convert smackfs to use the new mount API
  vfs: Convert selinuxfs to use the new mount API
  vfs: Convert securityfs to use the new mount API
  vfs: Convert apparmorfs to use the new mount API
  vfs: Convert openpromfs to use the new mount API
  vfs: Convert xenfs to use the new mount API
  vfs: Convert gadgetfs to use the new mount API
  vfs: Convert oprofilefs to use the new mount API
  vfs: Convert ibmasmfs to use the new mount API
  vfs: Convert qib_fs/ipathfs to use the new mount API
  vfs: Convert efivarfs to use the new mount API
  vfs: Convert configfs to use the new mount API
  vfs: Convert binfmt_misc to use the new mount API
  convenience helper: get_tree_single()
  convenience helper get_tree_nodev()
  vfs: Kill sget_userns()
  ...
2019-07-19 10:42:02 -07:00
Mauro Carvalho Chehab da82c92f11 docs: cgroup-v1: add it to the admin-guide book
Those files belong to the admin guide, so add them.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-15 11:03:02 -03:00
Linus Torvalds 237f83dfbe Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Some highlights from this development cycle:

   1) Big refactoring of ipv6 route and neigh handling to support
      nexthop objects configurable as units from userspace. From David
      Ahern.

   2) Convert explored_states in BPF verifier into a hash table,
      significantly decreased state held for programs with bpf2bpf
      calls, from Alexei Starovoitov.

   3) Implement bpf_send_signal() helper, from Yonghong Song.

   4) Various classifier enhancements to mvpp2 driver, from Maxime
      Chevallier.

   5) Add aRFS support to hns3 driver, from Jian Shen.

   6) Fix use after free in inet frags by allocating fqdirs dynamically
      and reworking how rhashtable dismantle occurs, from Eric Dumazet.

   7) Add act_ctinfo packet classifier action, from Kevin
      Darbyshire-Bryant.

   8) Add TFO key backup infrastructure, from Jason Baron.

   9) Remove several old and unused ISDN drivers, from Arnd Bergmann.

  10) Add devlink notifications for flash update status to mlxsw driver,
      from Jiri Pirko.

  11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski.

  12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes.

  13) Various enhancements to ipv6 flow label handling, from Eric
      Dumazet and Willem de Bruijn.

  14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van
      der Merwe, and others.

  15) Various improvements to axienet driver including converting it to
      phylink, from Robert Hancock.

  16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean.

  17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana
      Radulescu.

  18) Add devlink health reporting to mlx5, from Moshe Shemesh.

  19) Convert stmmac over to phylink, from Jose Abreu.

  20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from
      Shalom Toledo.

  21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera.

  22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel.

  23) Track spill/fill of constants in BPF verifier, from Alexei
      Starovoitov.

  24) Support bounded loops in BPF, from Alexei Starovoitov.

  25) Various page_pool API fixes and improvements, from Jesper Dangaard
      Brouer.

  26) Just like ipv4, support ref-countless ipv6 route handling. From
      Wei Wang.

  27) Support VLAN offloading in aquantia driver, from Igor Russkikh.

  28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy.

  29) Add flower GRE encap/decap support to nfp driver, from Pieter
      Jansen van Vuuren.

  30) Protect against stack overflow when using act_mirred, from John
      Hurley.

  31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen.

  32) Use page_pool API in netsec driver, Ilias Apalodimas.

  33) Add Google gve network driver, from Catherine Sullivan.

  34) More indirect call avoidance, from Paolo Abeni.

  35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan.

  36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek.

  37) Add MPLS manipulation actions to TC, from John Hurley.

  38) Add sending a packet to connection tracking from TC actions, and
      then allow flower classifier matching on conntrack state. From
      Paul Blakey.

  39) Netfilter hw offload support, from Pablo Neira Ayuso"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits)
  net/mlx5e: Return in default case statement in tx_post_resync_params
  mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync().
  net: dsa: add support for BRIDGE_MROUTER attribute
  pkt_sched: Include const.h
  net: netsec: remove static declaration for netsec_set_tx_de()
  net: netsec: remove superfluous if statement
  netfilter: nf_tables: add hardware offload support
  net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload
  net: flow_offload: add flow_block_cb_is_busy() and use it
  net: sched: remove tcf block API
  drivers: net: use flow block API
  net: sched: use flow block API
  net: flow_offload: add flow_block_cb_{priv, incref, decref}()
  net: flow_offload: add list handling functions
  net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free()
  net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_*
  net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND
  net: flow_offload: add flow_block_cb_setup_simple()
  net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC
  net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC
  ...
2019-07-11 10:55:49 -07:00
Linus Torvalds 3b99107f0e for-5.3/block-20190708
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl0jrIMQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgptlFD/9CNsBX+Aap2lO6wKNr6QISwNAK76GMzEay
 s4LSY2kGkXvzv8i89mCuY+8UVNI8WH2/22WnU+8CBAJOjWyFQMsIwH/mrq0oZWRD
 J6STJE8rTr6Fc2MvJUWryp/xdBh3+eDIsAdIZVHVAkIzqYPBnpIAwEIeIw8t0xsm
 v9ngpQ3WD6ep8tOj9pnG1DGKFg1CmukZCC/Y4CQV1vZtmm2I935zUwNV/TB+Egfx
 G8JSC0cSV02LMK88HCnA6MnC/XSUC0qgfXbnmP+TpKlgjVX+P/fuB3oIYcZEu2Rk
 3YBpIkhsQytKYbF42KRLsmBH72u6oB9G+tNZTgB1STUDrZqdtD9xwX1rjDlY0ZzP
 EUDnk48jl/cxbs+VZrHoE2TcNonLiymV7Kb92juHXdIYmKFQStprGcQUbMaTkMfB
 6BYrYLifWx0leu1JJ1i7qhNmug94BYCSCxcRmH0p6kPazPcY9LXNmDWMfMuBPZT7
 z79VLZnHF2wNXJyT1cBluwRYYJRT4osWZ3XUaBWFKDgf1qyvXJfrN/4zmgkEIyW7
 ivXC+KLlGkhntDlWo2pLKbbyOIKY1HmU6aROaI11k5Zyh0ixKB7tHKavK39l+NOo
 YB41+4l6VEpQEyxyRk8tO0sbHpKaKB+evVIK3tTwbY+Q0qTExErxjfWUtOgRWhjx
 iXJssPRo4w==
 =VSYT
 -----END PGP SIGNATURE-----

Merge tag 'for-5.3/block-20190708' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
 "This is the main block updates for 5.3. Nothing earth shattering or
  major in here, just fixes, additions, and improvements all over the
  map. This contains:

   - Series of documentation fixes (Bart)

   - Optimization of the blk-mq ctx get/put (Bart)

   - null_blk removal race condition fix (Bob)

   - req/bio_op() cleanups (Chaitanya)

   - Series cleaning up the segment accounting, and request/bio mapping
     (Christoph)

   - Series cleaning up the page getting/putting for bios (Christoph)

   - block cgroup cleanups and moving it to where it is used (Christoph)

   - block cgroup fixes (Tejun)

   - Series of fixes and improvements to bcache, most notably a write
     deadlock fix (Coly)

   - blk-iolatency STS_AGAIN and accounting fixes (Dennis)

   - Series of improvements and fixes to BFQ (Douglas, Paolo)

   - debugfs_create() return value check removal for drbd (Greg)

   - Use struct_size(), where appropriate (Gustavo)

   - Two lighnvm fixes (Heiner, Geert)

   - MD fixes, including a read balance and corruption fix (Guoqing,
     Marcos, Xiao, Yufen)

   - block opal shadow mbr additions (Jonas, Revanth)

   - sbitmap compare-and-exhange improvemnts (Pavel)

   - Fix for potential bio->bi_size overflow (Ming)

   - NVMe pull requests:
       - improved PCIe suspent support (Keith Busch)
       - error injection support for the admin queue (Akinobu Mita)
       - Fibre Channel discovery improvements (James Smart)
       - tracing improvements including nvmetc tracing support (Minwoo Im)
       - misc fixes and cleanups (Anton Eidelman, Minwoo Im, Chaitanya
         Kulkarni)"

   - Various little fixes and improvements to drivers and core"

* tag 'for-5.3/block-20190708' of git://git.kernel.dk/linux-block: (153 commits)
  blk-iolatency: fix STS_AGAIN handling
  block: nr_phys_segments needs to be zero for REQ_OP_WRITE_ZEROES
  blk-mq: simplify blk_mq_make_request()
  blk-mq: remove blk_mq_put_ctx()
  sbitmap: Replace cmpxchg with xchg
  block: fix .bi_size overflow
  block: sed-opal: check size of shadow mbr
  block: sed-opal: ioctl for writing to shadow mbr
  block: sed-opal: add ioctl for done-mark of shadow mbr
  block: never take page references for ITER_BVEC
  direct-io: use bio_release_pages in dio_bio_complete
  block_dev: use bio_release_pages in bio_unmap_user
  block_dev: use bio_release_pages in blkdev_bio_end_io
  iomap: use bio_release_pages in iomap_dio_bio_end_io
  block: use bio_release_pages in bio_map_user_iov
  block: use bio_release_pages in bio_unmap_user
  block: optionally mark pages dirty in bio_release_pages
  block: move the BIO_NO_PAGE_REF check into bio_release_pages
  block: skd_main.c: Remove call to memset after dma_alloc_coherent
  block: mtip32xx: Remove call to memset after dma_alloc_coherent
  ...
2019-07-09 10:45:06 -07:00
Linus Torvalds 92c1d65221 Merge branch 'for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
 "Documentation updates and the addition of cgroup_parse_float() which
  will be used by new controllers including blk-iocost"

* 'for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  docs: cgroup-v1: convert docs to ReST and rename to *.rst
  cgroup: Move cgroup_parse_float() implementation out of CONFIG_SYSFS
  cgroup: add cgroup_parse_float()
2019-07-08 21:35:12 -07:00
Linus Torvalds dad1c12ed8 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:

 - Remove the unused per rq load array and all its infrastructure, by
   Dietmar Eggemann.

 - Add utilization clamping support by Patrick Bellasi. This is a
   refinement of the energy aware scheduling framework with support for
   boosting of interactive and capping of background workloads: to make
   sure critical GUI threads get maximum frequency ASAP, and to make
   sure background processing doesn't unnecessarily move to cpufreq
   governor to higher frequencies and less energy efficient CPU modes.

 - Add the bare minimum of tracepoints required for LISA EAS regression
   testing, by Qais Yousef - which allows automated testing of various
   power management features, including energy aware scheduling.

 - Restructure the former tsk_nr_cpus_allowed() facility that the -rt
   kernel used to modify the scheduler's CPU affinity logic such as
   migrate_disable() - introduce the task->cpus_ptr value instead of
   taking the address of &task->cpus_allowed directly - by Sebastian
   Andrzej Siewior.

 - Misc optimizations, fixes, cleanups and small enhancements - see the
   Git log for details.

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
  sched/uclamp: Add uclamp support to energy_compute()
  sched/uclamp: Add uclamp_util_with()
  sched/cpufreq, sched/uclamp: Add clamps for FAIR and RT tasks
  sched/uclamp: Set default clamps for RT tasks
  sched/uclamp: Reset uclamp values on RESET_ON_FORK
  sched/uclamp: Extend sched_setattr() to support utilization clamping
  sched/core: Allow sched_setattr() to use the current policy
  sched/uclamp: Add system default clamps
  sched/uclamp: Enforce last task's UCLAMP_MAX
  sched/uclamp: Add bucket local max tracking
  sched/uclamp: Add CPU's clamp buckets refcounting
  sched/fair: Rename weighted_cpuload() to cpu_runnable_load()
  sched/debug: Export the newly added tracepoints
  sched/debug: Add sched_overutilized tracepoint
  sched/debug: Add new tracepoint to track PELT at se level
  sched/debug: Add new tracepoints to track PELT at rq level
  sched/debug: Add a new sched_trace_*() helper functions
  sched/autogroup: Make autogroup_path() always available
  sched/wait: Deduplicate code with do-while
  sched/topology: Remove unused 'sd' parameter from arch_scale_cpu_capacity()
  ...
2019-07-08 16:39:53 -07:00
Jens Axboe 5be1f9d82f Linux 5.2-rc6
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl0Os1seHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGtx4H/j6i482XzcGFKTBm
 A7mBoQpy+kLtoUov4EtBAR62OuwI8rsahW9di37QKndPoQrczWaKBmr3De6LCdPe
 v3pl3O6wBbvH5ru+qBPFX9PdNbDvimEChh7LHxmMxNQq3M+AjZAZVJyfpoiFnx35
 Fbge+LZaH/k8HMwZmkMr5t9Mpkip715qKg2o9Bua6dkH0AqlcpLlC8d9a+HIVw/z
 aAsyGSU8jRwhoAOJsE9bJf0acQ/pZSqmFp0rDKqeFTSDMsbDRKLGq/dgv4nW0RiW
 s7xqsjb/rdcvirRj3rv9+lcTVkOtEqwk0PVdL9WOf7g4iYrb3SOIZh8ZyViaDSeH
 VTS5zps=
 =huBY
 -----END PGP SIGNATURE-----

Merge tag 'v5.2-rc6' into for-5.3/block

Merge 5.2-rc6 into for-5.3/block, so we get the same page merge leak
fix. Otherwise we end up having conflicts with future patches between
for-5.3/block and master that touch this area. In particular, it makes
the bio_full() fix hard to backport to stable.

* tag 'v5.2-rc6': (482 commits)
  Linux 5.2-rc6
  Revert "iommu/vt-d: Fix lock inversion between iommu->lock and device_domain_lock"
  Bluetooth: Fix regression with minimum encryption key size alignment
  tcp: refine memory limit test in tcp_fragment()
  x86/vdso: Prevent segfaults due to hoisted vclock reads
  SUNRPC: Fix a credential refcount leak
  Revert "SUNRPC: Declare RPC timers as TIMER_DEFERRABLE"
  net :sunrpc :clnt :Fix xps refcount imbalance on the error path
  NFS4: Only set creation opendata if O_CREAT
  ARM: 8867/1: vdso: pass --be8 to linker if necessary
  KVM: nVMX: reorganize initial steps of vmx_set_nested_state
  KVM: PPC: Book3S HV: Invalidate ERAT when flushing guest TLB entries
  habanalabs: use u64_to_user_ptr() for reading user pointers
  nfsd: replace Jeff by Chuck as nfsd co-maintainer
  inet: clear num_timeout reqsk_alloc()
  PCI/P2PDMA: Ignore root complex whitelist when an IOMMU is present
  net: mvpp2: debugfs: Add pmap to fs dump
  ipv6: Default fib6_type to RTN_UNICAST when not set
  net: hns3: Fix inconsistent indenting
  net/af_iucv: always register net_device notifier
  ...
2019-07-01 08:16:08 -06:00
Ingo Molnar 83086d654d Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull rcu/next + tools/memory-model changes from Paul E. McKenney:

 - RCU flavor consolidation cleanups and optmizations
 - Documentation updates
 - Miscellaneous fixes
 - SRCU updates
 - RCU-sync flavor consolidation
 - Torture-test updates
 - Linux-kernel memory-consistency-model updates, most notably the addition of plain C-language accesses

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-28 19:46:47 +02:00
Ingo Molnar d2abae71eb Linux 5.2-rc6
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl0Os1seHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGtx4H/j6i482XzcGFKTBm
 A7mBoQpy+kLtoUov4EtBAR62OuwI8rsahW9di37QKndPoQrczWaKBmr3De6LCdPe
 v3pl3O6wBbvH5ru+qBPFX9PdNbDvimEChh7LHxmMxNQq3M+AjZAZVJyfpoiFnx35
 Fbge+LZaH/k8HMwZmkMr5t9Mpkip715qKg2o9Bua6dkH0AqlcpLlC8d9a+HIVw/z
 aAsyGSU8jRwhoAOJsE9bJf0acQ/pZSqmFp0rDKqeFTSDMsbDRKLGq/dgv4nW0RiW
 s7xqsjb/rdcvirRj3rv9+lcTVkOtEqwk0PVdL9WOf7g4iYrb3SOIZh8ZyViaDSeH
 VTS5zps=
 =huBY
 -----END PGP SIGNATURE-----

Merge tag 'v5.2-rc6' into sched/core, to refresh the branch

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-24 19:19:53 +02:00
David S. Miller 92ad6325cb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor SPDX change conflict.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-22 08:59:24 -04:00
Christoph Hellwig 474a280036 cgroup: export css_next_descendant_pre for bfq
The bfq schedule now uses css_next_descendant_pre directly after
the stats functionality depending on it has been from the core
blk-cgroup code to bfq.  Export the symbol so that bfq can still
be build modular.

Fixes: d6258980da ("bfq-iosched: move bfq_stat_recursive_sum into the only caller")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-21 02:48:34 -06:00
Thomas Gleixner f85d208658 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 451
Based on 1 normalized pattern(s):

  this file is subject to the terms and conditions of version 2 of the
  gnu general public license see the file copying in the main
  directory of the linux distribution for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 5 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081200.872755311@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:08 +02:00
David S. Miller 13091aa305 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Honestly all the conflicts were simple overlapping changes,
nothing really interesting to report.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-17 20:20:36 -07:00
Ingo Molnar 23da766ab1 Linux 5.2-rc5
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl0Gj1MeHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGctkH/0At3+SQPY2JJSy8
 i6+TDeytFx9OggeGLPHChRfehkAlvMb/kd34QHnuEvDqUuCAMU6HZQJFKoK9mvFI
 sDJVayPGDSqpm+iv8qLpMBPShiCXYVnGZeVfOdv36jUswL0k6wHV1pz4avFkDeZa
 1F4pmI6O2XRkNTYQawbUaFkAngWUCBG9ECLnHJnuIY6ohShBvjI4+E2JUaht+8gO
 M2h2b9ieddWmjxV3LTKgsK1v+347RljxdZTWnJ62SCDSEVZvsgSA9W2wnebVhBkJ
 drSmrFLxNiM+W45mkbUFmQixRSmjv++oRR096fxAnodBxMw0TDxE1RiMQWE6rVvG
 N6MC6xA=
 =+B0P
 -----END PGP SIGNATURE-----

Merge tag 'v5.2-rc5' into sched/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-17 12:12:27 +02:00
Linus Torvalds 0011572c88 Merge branch 'for-5.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
 "This has an unusually high density of tricky fixes:

   - task_get_css() could deadlock when it races against a dying cgroup.

   - cgroup.procs didn't list thread group leaders with live threads.

     This could mislead readers to think that a cgroup is empty when
     it's not. Fixed by making PROCS iterator include dead tasks. I made
     a couple mistakes making this change and this pull request contains
     a couple follow-up patches.

   - When cpusets run out of online cpus, it updates cpusmasks of member
     tasks in bizarre ways. Joel improved the behavior significantly"

* 'for-5.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cpuset: restore sanity to cpuset_cpus_allowed_fallback()
  cgroup: Fix css_task_iter_advance_css_set() cset skip condition
  cgroup: css_task_iter_skip()'d iterators must be advanced before accessed
  cgroup: Include dying leaders with live threads in PROCS iterations
  cgroup: Implement css_task_iter_skip()
  cgroup: Call cgroup_release() before __exit_signal()
  docs cgroups: add another example size for hugetlb
  cgroup: Use css_tryget() instead of css_tryget_online() in task_get_css()
2019-06-14 17:46:14 -10:00
Mauro Carvalho Chehab 99c8b231ae docs: cgroup-v1: convert docs to ReST and rename to *.rst
Convert the cgroup-v1 files to ReST format, in order to
allow a later addition to the admin-guide.

The conversion is actually:
  - add blank lines and identation in order to identify paragraphs;
  - fix tables markups;
  - add some lists markups;
  - mark literal blocks;
  - adjust title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2019-06-14 13:29:54 -07:00
Tejun Heo 38cf3a687f cgroup: Move cgroup_parse_float() implementation out of CONFIG_SYSFS
a5e112e642 ("cgroup: add cgroup_parse_float()") accidentally added
cgroup_parse_float() inside CONFIG_SYSFS block.  Move it outside so
that it doesn't cause failures on !CONFIG_SYSFS builds.

Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: a5e112e642 ("cgroup: add cgroup_parse_float()")
2019-06-14 10:14:44 -07:00
Joel Savitz d477f8c202 cpuset: restore sanity to cpuset_cpus_allowed_fallback()
In the case that a process is constrained by taskset(1) (i.e.
sched_setaffinity(2)) to a subset of available cpus, and all of those are
subsequently offlined, the scheduler will set tsk->cpus_allowed to
the current value of task_cs(tsk)->effective_cpus.

This is done via a call to do_set_cpus_allowed() in the context of
cpuset_cpus_allowed_fallback() made by the scheduler when this case is
detected. This is the only call made to cpuset_cpus_allowed_fallback()
in the latest mainline kernel.

However, this is not sane behavior.

I will demonstrate this on a system running the latest upstream kernel
with the following initial configuration:

	# grep -i cpu /proc/$$/status
	Cpus_allowed:	ffffffff,fffffff
	Cpus_allowed_list:	0-63

(Where cpus 32-63 are provided via smt.)

If we limit our current shell process to cpu2 only and then offline it
and reonline it:

	# taskset -p 4 $$
	pid 2272's current affinity mask: ffffffffffffffff
	pid 2272's new affinity mask: 4

	# echo off > /sys/devices/system/cpu/cpu2/online
	# dmesg | tail -3
	[ 2195.866089] process 2272 (bash) no longer affine to cpu2
	[ 2195.872700] IRQ 114: no longer affine to CPU2
	[ 2195.879128] smpboot: CPU 2 is now offline

	# echo on > /sys/devices/system/cpu/cpu2/online
	# dmesg | tail -1
	[ 2617.043572] smpboot: Booting Node 0 Processor 2 APIC 0x4

We see that our current process now has an affinity mask containing
every cpu available on the system _except_ the one we originally
constrained it to:

	# grep -i cpu /proc/$$/status
	Cpus_allowed:   ffffffff,fffffffb
	Cpus_allowed_list:      0-1,3-63

This is not sane behavior, as the scheduler can now not only place the
process on previously forbidden cpus, it can't even schedule it on
the cpu it was originally constrained to!

Other cases result in even more exotic affinity masks. Take for instance
a process with an affinity mask containing only cpus provided by smt at
the moment that smt is toggled, in a configuration such as the following:

	# taskset -p f000000000 $$
	# grep -i cpu /proc/$$/status
	Cpus_allowed:	000000f0,00000000
	Cpus_allowed_list:	36-39

A double toggle of smt results in the following behavior:

	# echo off > /sys/devices/system/cpu/smt/control
	# echo on > /sys/devices/system/cpu/smt/control
	# grep -i cpus /proc/$$/status
	Cpus_allowed:	ffffff00,ffffffff
	Cpus_allowed_list:	0-31,40-63

This is even less sane than the previous case, as the new affinity mask
excludes all smt-provided cpus with ids less than those that were
previously in the affinity mask, as well as those that were actually in
the mask.

With this patch applied, both of these cases end in the following state:

	# grep -i cpu /proc/$$/status
	Cpus_allowed:	ffffffff,ffffffff
	Cpus_allowed_list:	0-63

The original policy is discarded. Though not ideal, it is the simplest way
to restore sanity to this fallback case without reinventing the cpuset
wheel that rolls down the kernel just fine in cgroup v2. A user who wishes
for the previous affinity mask to be restored in this fallback case can use
that mechanism instead.

This patch modifies scheduler behavior by instead resetting the mask to
task_cs(tsk)->cpus_allowed by default, and cpu_possible mask in legacy
mode. I tested the cases above on both modes.

Note that the scheduler uses this fallback mechanism if and only if
_every_ other valid avenue has been traveled, and it is the last resort
before calling BUG().

Suggested-by: Waiman Long <longman@redhat.com>
Suggested-by: Phil Auld <pauld@redhat.com>
Signed-off-by: Joel Savitz <jsavitz@redhat.com>
Acked-by: Phil Auld <pauld@redhat.com>
Acked-by: Waiman Long <longman@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2019-06-12 11:00:08 -07:00
Tejun Heo 11dc8b4011 Merge branch 'for-5.2-fixes' into for-5.3 2019-06-10 09:12:39 -07:00
Tejun Heo c596687a00 cgroup: Fix css_task_iter_advance_css_set() cset skip condition
While adding handling for dying task group leaders c03cd7738a
("cgroup: Include dying leaders with live threads in PROCS
iterations") added an inverted cset skip condition to
css_task_iter_advance_css_set().  It should skip cset if it's
completely empty but was incorrectly testing for the inverse condition
for the dying_tasks list.  Fix it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Fixes: c03cd7738a ("cgroup: Include dying leaders with live threads in PROCS iterations")
Reported-by: syzbot+d4bba5ccd4f9a2a68681@syzkaller.appspotmail.com
2019-06-10 09:08:27 -07:00
Jens Axboe cf8929885d cgroup/bfq: revert bfq.weight symlink change
There's some discussion on how to do this the best, and Tejun prefers
that BFQ just create the file itself instead of having cgroups support
a symlink feature.

Hence revert commit 54b7b868e8 and 19e9da9e86 for 5.2, and this
can be done properly for 5.3.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-10 03:35:41 -06:00
David S. Miller a6cdeeb16b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Some ISDN files that got removed in net-next had some changes
done in mainline, take the removals.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-07 11:00:14 -07:00
Angelo Ruocco 54b7b868e8 cgroup: let a symlink too be created with a cftype file
This commit enables a cftype to have a symlink (of any name) that
points to the file associated with the cftype.

Signed-off-by: Angelo Ruocco <angeloruocco90@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-06-07 01:29:39 -06:00
Tejun Heo cee0c33c54 cgroup: css_task_iter_skip()'d iterators must be advanced before accessed
b636fd38dc ("cgroup: Implement css_task_iter_skip()") introduced
css_task_iter_skip() which is used to fix task iterations skipping
dying threadgroup leaders with live threads.  Skipping is implemented
as a subportion of full advancing but css_task_iter_next() forgot to
fully advance a skipped iterator before determining the next task to
visit causing it to return invalid task pointers.

Fix it by making css_task_iter_next() fully advance the iterator if it
has been skipped since the previous iteration.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: syzbot
Link: http://lkml.kernel.org/r/00000000000097025d058a7fd785@google.com
Fixes: b636fd38dc ("cgroup: Implement css_task_iter_skip()")
2019-06-05 09:54:34 -07:00
Sebastian Andrzej Siewior 3bd3706251 sched/core: Provide a pointer to the valid CPU mask
In commit:

  4b53a3412d ("sched/core: Remove the tsk_nr_cpus_allowed() wrapper")

the tsk_nr_cpus_allowed() wrapper was removed. There was not
much difference in !RT but in RT we used this to implement
migrate_disable(). Within a migrate_disable() section the CPU mask is
restricted to single CPU while the "normal" CPU mask remains untouched.

As an alternative implementation Ingo suggested to use:

	struct task_struct {
		const cpumask_t		*cpus_ptr;
		cpumask_t		cpus_mask;
        };
with
	t->cpus_ptr = &t->cpus_mask;

In -RT we then can switch the cpus_ptr to:

	t->cpus_ptr = &cpumask_of(task_cpu(p));

in a migration disabled region. The rules are simple:

 - Code that 'uses' ->cpus_allowed would use the pointer.
 - Code that 'modifies' ->cpus_allowed would use the direct mask.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190423142636.14347-1-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-06-03 11:49:37 +02:00
Chris Down 9852ae3fe5 mm, memcg: consider subtrees in memory.events
memory.stat and other files already consider subtrees in their output, and
we should too in order to not present an inconsistent interface.

The current situation is fairly confusing, because people interacting with
cgroups expect hierarchical behaviour in the vein of memory.stat,
cgroup.events, and other files.  For example, this causes confusion when
debugging reclaim events under low, as currently these always read "0" at
non-leaf memcg nodes, which frequently causes people to misdiagnose breach
behaviour.  The same confusion applies to other counters in this file when
debugging issues.

Aggregation is done at write time instead of at read-time since these
counters aren't hot (unlike memory.stat which is per-page, so it does it
at read time), and it makes sense to bundle this with the file
notifications.

After this patch, events are propagated up the hierarchy:

    [root@ktst ~]# cat /sys/fs/cgroup/system.slice/memory.events
    low 0
    high 0
    max 0
    oom 0
    oom_kill 0
    [root@ktst ~]# systemd-run -p MemoryMax=1 true
    Running as unit: run-r251162a189fb4562b9dabfdc9b0422f5.service
    [root@ktst ~]# cat /sys/fs/cgroup/system.slice/memory.events
    low 0
    high 0
    max 7
    oom 1
    oom_kill 1

As this is a change in behaviour, this can be reverted to the old
behaviour by mounting with the `memory_localevents' flag set.  However, we
use the new behaviour by default as there's a lack of evidence that there
are any current users of memory.events that would find this change
undesirable.

akpm: this is a behaviour change, so Cc:stable.  THis is so that
forthcoming distros which use cgroup v2 are more likely to pick up the
revised behaviour.

Link: http://lkml.kernel.org/r/20190208224419.GA24772@chrisdown.name
Signed-off-by: Chris Down <chris@chrisdown.name>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-06-01 15:51:31 -07:00
Tejun Heo a5e112e642 cgroup: add cgroup_parse_float()
cgroup already uses floating point for percent[ile] numbers and there
are several controllers which want to take them as input.  Add a
generic parse helper to handle inputs.

Update the interface convention documentation about the use of
percentage numbers.  While at it, also clarify the default time unit.

Signed-off-by: Tejun Heo <tj@kernel.org>
2019-05-31 11:48:40 -07:00
Tejun Heo c03cd7738a cgroup: Include dying leaders with live threads in PROCS iterations
CSS_TASK_ITER_PROCS currently iterates live group leaders; however,
this means that a process with dying leader and live threads will be
skipped.  IOW, cgroup.procs might be empty while cgroup.threads isn't,
which is confusing to say the least.

Fix it by making cset track dying tasks and include dying leaders with
live threads in PROCS iteration.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: Topi Miettinen <toiwoton@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
2019-05-31 10:38:58 -07:00
Tejun Heo b636fd38dc cgroup: Implement css_task_iter_skip()
When a task is moved out of a cset, task iterators pointing to the
task are advanced using the normal css_task_iter_advance() call.  This
is fine but we'll be tracking dying tasks on csets and thus moving
tasks from cset->tasks to (to be added) cset->dying_tasks.  When we
remove a task from cset->tasks, if we advance the iterators, they may
move over to the next cset before we had the chance to add the task
back on the dying list, which can allow the task to escape iteration.

This patch separates out skipping from advancing.  Skipping only moves
the affected iterators to the next pointer rather than fully advancing
it and the following advancing will recognize that the cursor has
already been moved forward and do the rest of advancing.  This ensures
that when a task moves from one list to another in its cset, as long
as it moves in the right direction, it's always visible to iteration.

This doesn't cause any visible behavior changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
2019-05-31 10:38:58 -07:00
Roman Gushchin 4bfc0bb2c6 bpf: decouple the lifetime of cgroup_bpf from cgroup itself
Currently the lifetime of bpf programs attached to a cgroup is bound
to the lifetime of the cgroup itself. It means that if a user
forgets (or intentionally avoids) to detach a bpf program before
removing the cgroup, it will stay attached up to the release of the
cgroup. Since the cgroup can stay in the dying state (the state
between being rmdir()'ed and being released) for a very long time, it
leads to a waste of memory. Also, it blocks a possibility to implement
the memcg-based memory accounting for bpf objects, because a circular
reference dependency will occur. Charged memory pages are pinning the
corresponding memory cgroup, and if the memory cgroup is pinning
the attached bpf program, nothing will be ever released.

A dying cgroup can not contain any processes, so the only chance for
an attached bpf program to be executed is a live socket associated
with the cgroup. So in order to release all bpf data early, let's
count associated sockets using a new percpu refcounter. On cgroup
removal the counter is transitioned to the atomic mode, and as soon
as it reaches 0, all bpf programs are detached.

Because cgroup_bpf_release() can block, it can't be called from
the percpu ref counter callback directly, so instead an asynchronous
work is scheduled.

The reference counter is not socket specific, and can be used for any
other types of programs, which can be executed from a cgroup-bpf hook
outside of the process context, had such a need arise in the future.

Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: jolsa@redhat.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-05-28 09:30:02 -07:00
Oleg Nesterov 3f2947b781 locking/percpu-rwsem: Add DEFINE_PERCPU_RWSEM(), use it to initialize cgroup_threadgroup_rwsem
Turn DEFINE_STATIC_PERCPU_RWSEM() into __DEFINE_PERCPU_RWSEM() with the
additional "is_static" argument to introduce DEFINE_PERCPU_RWSEM().

Change cgroup.c to use DEFINE_PERCPU_RWSEM(cgroup_threadgroup_rwsem).

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-05-28 09:05:23 -07:00
Al Viro d5f68d330c cpuset: move mount -t cpuset logics into cgroup.c
... and get rid of the weird dances in ->get_tree() - that logics
can be easily handled in ->init_fs_context().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-25 18:00:01 -04:00
Al Viro f7a9945184 no need to protect against put_user_ns(NULL)
it's a no-op

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-05-25 17:59:54 -04:00
Thomas Gleixner 457c899653 treewide: Add SPDX license identifier for missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have EXPORT_.*_SYMBOL_GPL inside which was used in the
   initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:45 +02:00
Dan Schatzberg df5ba5be74 kernel/sched/psi.c: expose pressure metrics on root cgroup
Pressure metrics are already recorded and exposed in procfs for the
entire system, but any tool which monitors cgroup pressure has to
special case the root cgroup to read from procfs.  This patch exposes
the already recorded pressure metrics on the root cgroup.

Link: http://lkml.kernel.org/r/20190510174938.3361741-1-dschatzberg@fb.com
Signed-off-by: Dan Schatzberg <dschatzberg@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:48 -07:00
Suren Baghdasaryan 0e94682b73 psi: introduce psi monitor
Psi monitor aims to provide a low-latency short-term pressure detection
mechanism configurable by users.  It allows users to monitor psi metrics
growth and trigger events whenever a metric raises above user-defined
threshold within user-defined time window.

Time window and threshold are both expressed in usecs.  Multiple psi
resources with different thresholds and window sizes can be monitored
concurrently.

Psi monitors activate when system enters stall state for the monitored
psi metric and deactivate upon exit from the stall state.  While system
is in the stall state psi signal growth is monitored at a rate of 10
times per tracking window.  Min window size is 500ms, therefore the min
monitoring interval is 50ms.  Max window size is 10s with monitoring
interval of 1s.

When activated psi monitor stays active for at least the duration of one
tracking window to avoid repeated activations/deactivations when psi
signal is bouncing.

Notifications to the users are rate-limited to one per tracking window.

Link: http://lkml.kernel.org/r/20190319235619.260832-8-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:48 -07:00
Linus Torvalds abde77eb5c Merge branch 'for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
 "This includes Roman's cgroup2 freezer implementation.

  It's a separate machanism from cgroup1 freezer. Instead of blocking
  user tasks in arbitrary uninterruptible sleeps, the new implementation
  extends jobctl stop - frozen tasks are trapped in jobctl stop until
  thawed and can be killed and ptraced. Lots of thanks to Oleg for
  sheperding the effort.

  Other than that, there are a few trivial changes"

* 'for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: never call do_group_exit() with task->frozen bit set
  kernel: cgroup: fix misuse of %x
  cgroup: get rid of cgroup_freezer_frozen_exit()
  cgroup: prevent spurious transition into non-frozen state
  cgroup: Remove unused cgrp variable
  cgroup: document cgroup v2 freezer interface
  cgroup: add tracing points for cgroup v2 freezer
  cgroup: make TRACE_CGROUP_PATH irq-safe
  kselftests: cgroup: add freezer controller self-tests
  kselftests: cgroup: don't fail on cg_kill_all() error in cg_destroy()
  cgroup: cgroup v2 freezer
  cgroup: protect cgroup->nr_(dying_)descendants by css_set_lock
  cgroup: implement __cgroup_task_count() helper
  cgroup: rename freezer.c into legacy_freezer.c
  cgroup: remove extra cgroup_migrate_finish() call
2019-05-09 13:52:12 -07:00
Fuqian Huang 1900da520c kernel: cgroup: fix misuse of %x
Pointers should be printed with %p or %px rather than
cast to unsigned long type and printed with %lx.
Change %lx to %p to print the pointers.

Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2019-05-06 08:47:48 -07:00
Roman Gushchin 96b9c592de cgroup: get rid of cgroup_freezer_frozen_exit()
A task should never enter the exit path with the task->frozen bit set.
Any frozen task must enter the signal handling loop and the only
way to escape is through cgroup_leave_frozen(true), which
unconditionally drops the task->frozen bit. So it means that
cgroyp_freezer_frozen_exit() has zero chances to be called and
has to be removed.

Let's put a WARN_ON_ONCE() instead of the cgroup_freezer_frozen_exit()
call to catch any potential leak of the task's frozen bit.

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2019-05-06 08:39:11 -07:00
Roman Gushchin cb2c4cd878 cgroup: prevent spurious transition into non-frozen state
If freezing of a cgroup races with waking of a task from
the frozen state (like waiting in vfork() or in do_signal_stop()),
a spurious transition of the cgroup state can happen.

The task enters cgroup_leave_frozen(true), the cgroup->nr_frozen_tasks
counter decrements, and the cgroup is switched to the unfrozen state.

To prevent it, let's reserve cgroup_leave_frozen(true) for
terminating processes and use cgroup_leave_frozen(false) otherwise.

To avoid busy-looping in the signal handling loop waiting
for JOBCTL_TRAP_FREEZE set from the cgroup freezing path,
let's do it explicitly in cgroup_leave_frozen(), if the task
is going to stay frozen.

Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
2019-05-06 08:39:06 -07:00