forked from Minki/linux
f7fdcb6010
221 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Linus Torvalds
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5ebe0ee802 |
There is a nice new document from Neil on how pathname lookups work and
some new CAN driver documentation. Beyond that, we have kernel-doc fixes, a bit more work to support reproducible builds, and the usual collection of small fixes. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJWO6HiAAoJEI3ONVYwIuV6ihwQAK0KC72h0706bdwDJ1p1/aJU QLuPeiKYWgGAXq2zgOyw3Povj4bkMwkiq1IGHLyK0Id4tg3ngxOXjimk4YKrqarI BD5HdpOm7IyQEe66ZU9b1RFDVst+bg3yp6ZIZsH5vQxl/KnyJ6AyaaDk8TPYId8S 1+CykJzxyi7GyT/jlLpHbKtBKrraoVke+cNPMAvOf0NjSyO7Ix5B+qH50sttG6Eu 9qcQ8hlKXOdZRTiGW6P+jeZNA+e5+CRpnG9VHBquHy4lI85kQThhWq41UMH690PP eRbLipeUybb0FwW2KwuMjGKEMDkMvrGJh0TzSXX9lGHd+5/41v7zcyKh8vJcpLjh bNQ2WOAKUBd2d15EP1MNoKXDLGJXusJczLwOjigWiSCQvgouAWwMrpWEw+Obv8Yl rdoH1oQqDFfDnk6mnKrSaqLWGNuLxDtkEl/1P0jsGSK6lM3FDkOgTuNPYXTJJgxN rXuGmPhyUlS2srERUeQJw2rISN0WRBvcKJGkMX6IpvrXHkItbelqK+yY1DeKPmcm qgbIx9ZWNqtltFpG22VVByqAVwucO5Nu8cAIQ2ysJsTnKOvQCQmhu5UKTjBCkEJM VpeMm32BfNiJFLuLTQGWBZ8bkRl2shQyXhOaR3uyqG4T+rpPD3qJi6dtFRpsAzOB q1nZuJCpOaxJFzjSKvpJ =emZ7 -----END PGP SIGNATURE----- Merge tag 'docs-for-linus' of git://git.lwn.net/linux Pull documentation update from Jon Corbet: "There is a nice new document from Neil on how pathname lookups work and some new CAN driver documentation. Beyond that, we have kernel-doc fixes, a bit more work to support reproducible builds, and the usual collection of small fixes" * tag 'docs-for-linus' of git://git.lwn.net/linux: (34 commits) Documentation: add new description of path-name lookup. Documentation/vm/slub.txt: document slabinfo-gnuplot.sh Doc: ABI/stable: Fix typo in ABI/stable doc: Clarify that nmi_watchdog param is for hardlockups Typo correction for description in gpio document. DocBook: Fix kernel-doc to be case-insensitive for private: kernel-docs.txt: update kernelnewbies reference Doc:kvm: Fix typo in Doc/virtual/kvm Documentation/Changes: Add bc in "Current Minimal Requirements" section Documentation/email-clients.txt: remove trailing whitespace DocBook: Use a fixed encoding for output MAINTAINERS: The docs tree has moved Docs/kernel-parameters: Add earlycon devicetree usage SubmittingPatches: make Subject examples match the de facto standard Documentation: gpio: mention that <function>-gpio has been deprecated Documentation: cgroups: just fix a few typos Documentation: Update kselftest.txt Documentation: DMA API: Be more explicit that nents is always the same Documentation: Update the default value of crashkernel low zram: update documentation ... |
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Tejun Heo
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e4b7037c86 |
cgroup: drop cgroup__DEVEL__legacy_files_on_dfl
Now that interfaces for the major three controllers - cpu, memory, io - are shaping up, there's no reason to have an option to force legacy files to show up on the unified hierarchy for testing. Drop it. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org> |
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Tejun Heo
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afcf6c8b75 |
cgroup: add cgroup_subsys->free() method and use it to fix pids controller
pids controller is completely broken in that it uncharges when a task exits allowing zombies to escape resource control. With the recent updates, cgroup core now maintains cgroup association till task free and pids controller can be fixed by uncharging on free instead of exit. This patch adds cgroup_subsys->free() method and update pids controller to use it instead of ->exit() for uncharging. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Aleksa Sarai <cyphar@cyphar.com> |
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Tejun Heo
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2e91fa7f6d |
cgroup: keep zombies associated with their original cgroups
cgroup_exit() is called when a task exits and disassociates the
exiting task from its cgroups and half-attach it to the root cgroup.
This is unnecessary and undesirable.
No controller actually needs an exiting task to be disassociated with
non-root cgroups. Both cpu and perf_event controllers update the
association to the root cgroup from their exit callbacks just to keep
consistent with the cgroup core behavior.
Also, this disassociation makes it difficult to track resources held
by zombies or determine where the zombies came from. Currently, pids
controller is completely broken as it uncharges on exit and zombies
always escape the resource restriction. With cgroup association being
reset on exit, fixing it is pretty painful.
There's no reason to reset cgroup membership on exit. The zombie can
be removed from its css_set so that it doesn't show up on
"cgroup.procs" and thus can't be migrated or interfere with cgroup
removal. It can still pin and point to the css_set so that its cgroup
membership is maintained. This patch makes cgroup core keep zombies
associated with their cgroups at the time of exit.
* Previous patches decoupled populated_cnt tracking from css_set
lifetime, so a dying task can be simply unlinked from its css_set
while pinning and pointing to the css_set. This keeps css_set
association from task side alive while hiding it from "cgroup.procs"
and populated_cnt tracking. The css_set reference is dropped when
the task_struct is freed.
* ->exit() callback no longer needs the css arguments as the
associated css never changes once PF_EXITING is set. Removed.
* cpu and perf_events controllers no longer need ->exit() callbacks.
There's no reason to explicitly switch away on exit. The final
schedule out is enough. The callbacks are removed.
* On traditional hierarchies, nothing changes. "/proc/PID/cgroup"
still reports "/" for all zombies. On the default hierarchy,
"/proc/PID/cgroup" keeps reporting the cgroup that the task belonged
to at the time of exit. If the cgroup gets removed before the task
is reaped, " (deleted)" is appended.
v2: Build brekage due to missing dummy cgroup_free() when
!CONFIG_CGROUP fixed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
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Yuan Sun
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55d0159541 |
Documentation: cgroups: just fix a few typos
Just fix some typos in blkio-controller.txt, freezer-subsystem.txt, unified-hierarchy.txt. Signed-off-by: Yuan Sun <sunyuan3@huawei.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> |
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Tejun Heo
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4a07c222d3 |
cgroup: replace "cgroup.populated" with "cgroup.events"
memcg already uses "memory.events" for event reporting and other controllers may need event reporting too. Let's standardize on "$SUBSYS.events" interface file for reporting events which don't happen too frequently and thus can share event notification. "cgroup.populated" is replaced with "populated" field in "cgroup.events" and documentation is updated accordingly. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org> |
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Linus Torvalds
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b0a1ea51bd |
Merge branch 'for-4.3/blkcg' of git://git.kernel.dk/linux-block
Pull blk-cg updates from Jens Axboe:
"A bit later in the cycle, but this has been in the block tree for a a
while. This is basically four patchsets from Tejun, that improve our
buffered cgroup writeback. It was dependent on the other cgroup
changes, but they went in earlier in this cycle.
Series 1 is set of 5 patches that has cgroup writeback updates:
- bdi_writeback iteration fix which could lead to some wb's being
skipped or repeated during e.g. sync under memory pressure.
- Simplification of wb work wait mechanism.
- Writeback tracepoints updated to report cgroup.
Series 2 is is a set of updates for the CFQ cgroup writeback handling:
cfq has always charged all async IOs to the root cgroup. It didn't
have much choice as writeback didn't know about cgroups and there
was no way to tell who to blame for a given writeback IO.
writeback finally grew support for cgroups and now tags each
writeback IO with the appropriate cgroup to charge it against.
This patchset updates cfq so that it follows the blkcg each bio is
tagged with. Async cfq_queues are now shared across cfq_group,
which is per-cgroup, instead of per-request_queue cfq_data. This
makes all IOs follow the weight based IO resource distribution
implemented by cfq.
- Switched from GFP_ATOMIC to GFP_NOWAIT as suggested by Jeff.
- Other misc review points addressed, acks added and rebased.
Series 3 is the blkcg policy cleanup patches:
This patchset contains assorted cleanups for blkcg_policy methods
and blk[c]g_policy_data handling.
- alloc/free added for blkg_policy_data. exit dropped.
- alloc/free added for blkcg_policy_data.
- blk-throttle's async percpu allocation is replaced with direct
allocation.
- all methods now take blk[c]g_policy_data instead of blkcg_gq or
blkcg.
And finally, series 4 is a set of patches cleaning up the blkcg stats
handling:
blkcg's stats have always been somwhat of a mess. This patchset
tries to improve the situation a bit.
- The following patches added to consolidate blkcg entry point and
blkg creation. This is in itself is an improvement and helps
colllecting common stats on bio issue.
- per-blkg stats now accounted on bio issue rather than request
completion so that bio based and request based drivers can behave
the same way. The issue was spotted by Vivek.
- cfq-iosched implements custom recursive stats and blk-throttle
implements custom per-cpu stats. This patchset make blkcg core
support both by default.
- cfq-iosched and blk-throttle keep track of the same stats
multiple times. Unify them"
* 'for-4.3/blkcg' of git://git.kernel.dk/linux-block: (45 commits)
blkcg: use CGROUP_WEIGHT_* scale for io.weight on the unified hierarchy
blkcg: s/CFQ_WEIGHT_*/CFQ_WEIGHT_LEGACY_*/
blkcg: implement interface for the unified hierarchy
blkcg: misc preparations for unified hierarchy interface
blkcg: separate out tg_conf_updated() from tg_set_conf()
blkcg: move body parsing from blkg_conf_prep() to its callers
blkcg: mark existing cftypes as legacy
blkcg: rename subsystem name from blkio to io
blkcg: refine error codes returned during blkcg configuration
blkcg: remove unnecessary NULL checks from __cfqg_set_weight_device()
blkcg: reduce stack usage of blkg_rwstat_recursive_sum()
blkcg: remove cfqg_stats->sectors
blkcg: move io_service_bytes and io_serviced stats into blkcg_gq
blkcg: make blkg_[rw]stat_recursive_sum() to be able to index into blkcg_gq
blkcg: make blkcg_[rw]stat per-cpu
blkcg: add blkg_[rw]stat->aux_cnt and replace cfq_group->dead_stats with it
blkcg: consolidate blkg creation in blkcg_bio_issue_check()
blk-throttle: improve queue bypass handling
blkcg: move root blkg lookup optimization from throtl_lookup_tg() to __blkg_lookup()
blkcg: inline [__]blkg_lookup()
...
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Tejun Heo
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20f1f4b5ff | Merge branch 'for-4.3-unified-base' into for-4.3 | ||
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Tejun Heo
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69d7fde590 |
blkcg: use CGROUP_WEIGHT_* scale for io.weight on the unified hierarchy
cgroup is trying to make interface consistent across different controllers. For weight based resource control, the knob should have the range [1, 10000] and default to 100. This patch updates cfq-iosched so that the weight range conforms. The internal calculations have enough range and the widening of the weight range shouldn't cause any problem. * blkcg_policy->cpd_bind_fn() is added. If present, this is invoked when blkcg is attached to a hierarchy. * cfq_cpd_init() is updated to use the new default value on the unified hierarchy. * cfq_cpd_bind() callback is implemented to clear per-blkg configs and apply the default config matching the hierarchy type. * cfqd->root_group->[leaf_]weight initialization in cfq_init_queue() is moved into !CONFIG_CFQ_GROUP_IOSCHED block. cfq_cpd_bind() is now responsible for initializing the initial weights when blkcg is enabled. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Arianna Avanzini <avanzini.arianna@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com> |
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Tejun Heo
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2ee867dcfa |
blkcg: implement interface for the unified hierarchy
blkcg interface grew to be the biggest of all controllers and
unfortunately most inconsistent too. The interface files are
inconsistent with a number of cloes duplicates. Some files have
recursive variants while others don't. There's distinction between
normal and leaf weights which isn't intuitive and there are a lot of
stat knobs which don't make much sense outside of debugging and expose
too much implementation details to userland.
In the unified hierarchy, everything is always hierarchical and
internal nodes can't have tasks rendering the two structural issues
twisting the current interface. The interface has to be updated in a
significant anyway and this is a good chance to revamp it as a whole.
This patch implements blkcg interface for the unified hierarchy.
* (from a previous patch) blkcg is identified by "io" instead of
"blkio" on the unified hierarchy. Given that the whole interface is
updated anyway, the rename shouldn't carry noticeable conversion
overhead.
* The original interface consisted of 27 files is replaced with the
following three files.
blkio.stat : per-blkcg stats
blkio.weight : per-cgroup and per-cgroup-queue weight settings
blkio.max : per-cgroup-queue bps and iops max limits
Documentation/cgroups/unified-hierarchy.txt updated accordingly.
v2: blkcg_policy->dfl_cftypes wasn't removed on
blkcg_policy_unregister() corrupting the cftypes list. Fixed.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
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Tejun Heo
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77ea733884 |
blkcg: move io_service_bytes and io_serviced stats into blkcg_gq
Currently, both cfq-iosched and blk-throttle keep track of
io_service_bytes and io_serviced stats. While keeping track of them
separately may be useful during development, it doesn't make much
sense otherwise. Also, blk-throttle was counting bio's as IOs while
cfq-iosched request's, which is more confusing than informative.
This patch adds ->stat_bytes and ->stat_ios to blkg (blkcg_gq),
removes the counterparts from cfq-iosched and blk-throttle and let
them print from the common blkg counters. The common counters are
incremented during bio issue in blkcg_bio_issue_check().
The outputs are still filtered by whether the policy has
blkg_policy_data on a given blkg, so cfq's output won't show up if it
has never been used for a given blkg. The only times when the outputs
would differ significantly are when policies are attached on the fly
or elevators are switched back and forth. Those are quite exceptional
operations and I don't think they warrant keeping separate counters.
v3: Update blkio-controller.txt accordingly.
v2: Account IOs during bio issues instead of request completions so
that bio-based drivers can be handled the same way.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
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Tejun Heo
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6abc8ca19d |
cgroup: define controller file conventions
Traditionally, each cgroup controller implemented whatever interface it wanted leading to interfaces which are widely inconsistent. Examining the requirements of the controllers readily yield that there are only a few control schemes shared among all. Two major controllers already had to implement new interface for the unified hierarchy due to significant structural changes. Let's take the chance to establish common conventions throughout all controllers. This patch defines CGROUP_WEIGHT_MIN/DFL/MAX to be used on all weight based control knobs and documents the conventions that controllers should follow on the unified hierarchy. Except for io.weight knob, all existing unified hierarchy knobs are already compliant. A follow-up patch will update io.weight. v2: Added descriptions of min, low and high knobs. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Li Zefan <lizefan@huawei.com> Cc: Peter Zijlstra <peterz@infradead.org> |
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Aleksa Sarai
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917d8e2d10 |
cgroup: add documentation for the PIDs controller
Add documentation derived from kernel/cgroup_pids.c to the relevant Documentation/ directory, along with a few examples of how to use the PIDs controller as well an explanation of its peculiarities. Signed-off-by: Aleksa Sarai <cyphar@cyphar.com> Signed-off-by: Tejun Heo <tj@kernel.org> |
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Linus Torvalds
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bbe179f88d |
Merge branch 'for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo: - threadgroup_lock got reorganized so that its users can pick the actual locking mechanism to use. Its only user - cgroups - is updated to use a percpu_rwsem instead of per-process rwsem. This makes things a bit lighter on hot paths and allows cgroups to perform and fail multi-task (a process) migrations atomically. Multi-task migrations are used in several places including the unified hierarchy. - Delegation rule and documentation added to unified hierarchy. This will likely be the last interface update from the cgroup core side for unified hierarchy before lifting the devel mask. - Some groundwork for the pids controller which is scheduled to be merged in the coming devel cycle. * 'for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: add delegation section to unified hierarchy documentation cgroup: require write perm on common ancestor when moving processes on the default hierarchy cgroup: separate out cgroup_procs_write_permission() from __cgroup_procs_write() kernfs: make kernfs_get_inode() public MAINTAINERS: add a cgroup core co-maintainer cgroup: fix uninitialised iterator in for_each_subsys_which cgroup: replace explicit ss_mask checking with for_each_subsys_which cgroup: use bitmask to filter for_each_subsys cgroup: add seq_file forward declaration for struct cftype cgroup: simplify threadgroup locking sched, cgroup: replace signal_struct->group_rwsem with a global percpu_rwsem sched, cgroup: reorganize threadgroup locking cgroup: switch to unsigned long for bitmasks cgroup: reorganize include/linux/cgroup.h cgroup: separate out include/linux/cgroup-defs.h cgroup: fix some comment typos |
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Tejun Heo
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8a0792ef8e |
cgroup: add delegation section to unified hierarchy documentation
v2: Rearranged paragraphs as suggested by Johannes Weiner. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Johannes Weiner <hannes@cmpxchg.org> |
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Tejun Heo
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3e1534cf4a |
writeback, blkio: add documentation for cgroup writeback support
Update Documentation/cgroups/blkio-controller.txt to reflect the recently added cgroup writeback support. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Li Zefan <lizefan@huawei.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: cgroups@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Jens Axboe <axboe@fb.com> |
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Greg Thelen
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c4843a7593 |
memcg: add per cgroup dirty page accounting
When modifying PG_Dirty on cached file pages, update the new
MEM_CGROUP_STAT_DIRTY counter. This is done in the same places where
global NR_FILE_DIRTY is managed. The new memcg stat is visible in the
per memcg memory.stat cgroupfs file. The most recent past attempt at
this was http://thread.gmane.org/gmane.linux.kernel.cgroups/8632
The new accounting supports future efforts to add per cgroup dirty
page throttling and writeback. It also helps an administrator break
down a container's memory usage and provides evidence to understand
memcg oom kills (the new dirty count is included in memcg oom kill
messages).
The ability to move page accounting between memcg
(memory.move_charge_at_immigrate) makes this accounting more
complicated than the global counter. The existing
mem_cgroup_{begin,end}_page_stat() lock is used to serialize move
accounting with stat updates.
Typical update operation:
memcg = mem_cgroup_begin_page_stat(page)
if (TestSetPageDirty()) {
[...]
mem_cgroup_update_page_stat(memcg)
}
mem_cgroup_end_page_stat(memcg)
Summary of mem_cgroup_end_page_stat() overhead:
- Without CONFIG_MEMCG it's a no-op
- With CONFIG_MEMCG and no inter memcg task movement, it's just
rcu_read_lock()
- With CONFIG_MEMCG and inter memcg task movement, it's
rcu_read_lock() + spin_lock_irqsave()
A memcg parameter is added to several routines because their callers
now grab mem_cgroup_begin_page_stat() which returns the memcg later
needed by for mem_cgroup_update_page_stat().
Because mem_cgroup_begin_page_stat() may disable interrupts, some
adjustments are needed:
- move __mark_inode_dirty() from __set_page_dirty() to its caller.
__mark_inode_dirty() locking does not want interrupts disabled.
- use spin_lock_irqsave(tree_lock) rather than spin_lock_irq() in
__delete_from_page_cache(), replace_page_cache_page(),
invalidate_complete_page2(), and __remove_mapping().
text data bss dec hex filename
8925147 1774832 1785856 12485835 be84cb vmlinux-!CONFIG_MEMCG-before
8925339 1774832 1785856 12486027 be858b vmlinux-!CONFIG_MEMCG-after
+192 text bytes
8965977 1784992 1785856 12536825 bf4bf9 vmlinux-CONFIG_MEMCG-before
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Linus Torvalds
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d6a24d0640 |
The documentation tree update for 4.1. Numerous fixes, the overdue removal
of the i2o docs, some new Chinese translations, and, hopefully, the README fix that will end the flow of identical patches to that file. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJVMOeZAAoJEI3ONVYwIuV6/1YQAJwcVvd3ow6cMKuf8eRKMgjd crJUdRF9FTwyY21SRHBaonyiKOthnVedOUYnFQ5Z7jbII0EohJ//72nW0pQrHoGi 0avkbM+ZAZzXfd/paOiZ5HtYkc8Bdc70mPU1fzfexnPm/JACOGznxQsob05r6/sT W1GyJcrLlp4uPrba9rhAdGtaa+mEFrt4SVCI+odXOnxQ/KOZSIu1n1F3bSSvL9zV YMBgRrCso+Cdtuhe4N3O1jsVy/hyOnvtqcUgwlD4VzElsshKvxdxHn47yeeWK1qI zZfGTv+q5QI/eZgIhBIrBpdCafgLipAmNZhX+M76xeNydhfhp60VizRgKfb6JiW1 M+nLSnv2vxh4wgkJs7yWgW+8TJ0eCF/w2P/mBi6hDXuIul9gwgmNk+EZ7LONSh+2 l3PV/dyswNs04qbYgFt2rygsxcg79RRbD54zi+S/3NU38/gh7nlidASKmNu1boG/ KdZx3F0rmX/xQu4aQ5nIQl2N7sVLkEec+oN+ukQGyBTLVHkfAK06Z4EWUeYmmBKh M6gqRY5XJMtCm8D5bons/yZmwmpdZFZMxFGJ4enUwrfsJ8FQ8qy/KmFqF8SojGWQ HYs4ZUptz6SYa7K0Txe/q0pkrW+doy7t/Bz+JBNNdG7eLeHIpKhSqSlLIdB7MRKw NFA8a4PdgdMpf+Zr4bRy =LDbk -----END PGP SIGNATURE----- Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6 Pull documentation updates from Jonathan Corbet: "Numerous fixes, the overdue removal of the i2o docs, some new Chinese translations, and, hopefully, the README fix that will end the flow of identical patches to that file" * tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (34 commits) Documentation/memcg: update memcg/kmem status Documentation: blackfin: Makefile: Typo building issue Documentation/vm/pagemap.txt: correct location of page-types tool Documentation/memory-barriers.txt: typo fix doc: Add guest_nice column to example output of `cat /proc/stat' Documentation/kernel-parameters: Move "eagerfpu" to its right place Documentation: gpio: Update ACPI part of the document to mention _DSD docs/completion.txt: Various tweaks and corrections doc: completion: context, scope and language fixes Documentation:Update Documentation/zh_CN/arm64/memory.txt Documentation:Update Documentation/zh_CN/arm64/booting.txt Documentation: Chinese translation of arm64/legacy_instructions.txt DocBook media: fix broken EIA hyperlink Documentation: tweak the maintainers entry README: Change gzip/bzip2 to xz compression format README: Update version number reference doc:pci: Fix typo in Documentation/PCI Documentation: drm: Use '->' when describing access through pointers. Documentation: Remove mentioning of block barriers Documentation/email-clients.txt: Fix one grammar mistake, add extra info about TB ... |
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Linus Torvalds
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4fd48b45ff |
Merge branch 'for-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo: "Nothing too interesting. Rik made cpuset cooperate better with isolcpus and there are several other cleanup patches" * 'for-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cpuset, isolcpus: document relationship between cpusets & isolcpus cpusets, isolcpus: exclude isolcpus from load balancing in cpusets sched, isolcpu: make cpu_isolated_map visible outside scheduler cpuset: initialize cpuset a bit early cgroup: Use kvfree in pidlist_free() cgroup: call cgroup_subsys->bind on cgroup subsys initialization |
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Vladimir Davydov
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197175427a |
Documentation/memcg: update memcg/kmem status
Memcg/kmem reclaim support has been finally merged. Reflect this in the documentation. Acked-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> |
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Rik van Riel
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34ebe93341 |
cpuset, isolcpus: document relationship between cpusets & isolcpus
Document the subtly changed relationship between cpusets and isolcpus. Turns out the old documentation did not match the code... Signed-off-by: Rik van Riel <riel@redhat.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Zefan Li <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org> |
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Johannes Weiner
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d2973697b3 |
mm: memcontrol: use "max" instead of "infinity" in control knobs
The memcg control knobs indicate the highest possible value using the symbolic name "infinity", which is long and awkward to type. Switch to the string "max", which is just as descriptive but shorter and sweeter. This changes a user interface, so do it before the release and before the development flag is dropped from the default hierarchy. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Tejun Heo <tj@kernel.org> Cc: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Johannes Weiner
|
241994ed86 |
mm: memcontrol: default hierarchy interface for memory
Introduce the basic control files to account, partition, and limit
memory using cgroups in default hierarchy mode.
This interface versioning allows us to address fundamental design
issues in the existing memory cgroup interface, further explained
below. The old interface will be maintained indefinitely, but a
clearer model and improved workload performance should encourage
existing users to switch over to the new one eventually.
The control files are thus:
- memory.current shows the current consumption of the cgroup and its
descendants, in bytes.
- memory.low configures the lower end of the cgroup's expected
memory consumption range. The kernel considers memory below that
boundary to be a reserve - the minimum that the workload needs in
order to make forward progress - and generally avoids reclaiming
it, unless there is an imminent risk of entering an OOM situation.
- memory.high configures the upper end of the cgroup's expected
memory consumption range. A cgroup whose consumption grows beyond
this threshold is forced into direct reclaim, to work off the
excess and to throttle new allocations heavily, but is generally
allowed to continue and the OOM killer is not invoked.
- memory.max configures the hard maximum amount of memory that the
cgroup is allowed to consume before the OOM killer is invoked.
- memory.events shows event counters that indicate how often the
cgroup was reclaimed while below memory.low, how often it was
forced to reclaim excess beyond memory.high, how often it hit
memory.max, and how often it entered OOM due to memory.max. This
allows users to identify configuration problems when observing a
degradation in workload performance. An overcommitted system will
have an increased rate of low boundary breaches, whereas increased
rates of high limit breaches, maximum hits, or even OOM situations
will indicate internally overcommitted cgroups.
For existing users of memory cgroups, the following deviations from
the current interface are worth pointing out and explaining:
- The original lower boundary, the soft limit, is defined as a limit
that is per default unset. As a result, the set of cgroups that
global reclaim prefers is opt-in, rather than opt-out. The costs
for optimizing these mostly negative lookups are so high that the
implementation, despite its enormous size, does not even provide
the basic desirable behavior. First off, the soft limit has no
hierarchical meaning. All configured groups are organized in a
global rbtree and treated like equal peers, regardless where they
are located in the hierarchy. This makes subtree delegation
impossible. Second, the soft limit reclaim pass is so aggressive
that it not just introduces high allocation latencies into the
system, but also impacts system performance due to overreclaim, to
the point where the feature becomes self-defeating.
The memory.low boundary on the other hand is a top-down allocated
reserve. A cgroup enjoys reclaim protection when it and all its
ancestors are below their low boundaries, which makes delegation
of subtrees possible. Secondly, new cgroups have no reserve per
default and in the common case most cgroups are eligible for the
preferred reclaim pass. This allows the new low boundary to be
efficiently implemented with just a minor addition to the generic
reclaim code, without the need for out-of-band data structures and
reclaim passes. Because the generic reclaim code considers all
cgroups except for the ones running low in the preferred first
reclaim pass, overreclaim of individual groups is eliminated as
well, resulting in much better overall workload performance.
- The original high boundary, the hard limit, is defined as a strict
limit that can not budge, even if the OOM killer has to be called.
But this generally goes against the goal of making the most out of
the available memory. The memory consumption of workloads varies
during runtime, and that requires users to overcommit. But doing
that with a strict upper limit requires either a fairly accurate
prediction of the working set size or adding slack to the limit.
Since working set size estimation is hard and error prone, and
getting it wrong results in OOM kills, most users tend to err on
the side of a looser limit and end up wasting precious resources.
The memory.high boundary on the other hand can be set much more
conservatively. When hit, it throttles allocations by forcing
them into direct reclaim to work off the excess, but it never
invokes the OOM killer. As a result, a high boundary that is
chosen too aggressively will not terminate the processes, but
instead it will lead to gradual performance degradation. The user
can monitor this and make corrections until the minimal memory
footprint that still gives acceptable performance is found.
In extreme cases, with many concurrent allocations and a complete
breakdown of reclaim progress within the group, the high boundary
can be exceeded. But even then it's mostly better to satisfy the
allocation from the slack available in other groups or the rest of
the system than killing the group. Otherwise, memory.max is there
to limit this type of spillover and ultimately contain buggy or
even malicious applications.
- The original control file names are unwieldy and inconsistent in
many different ways. For example, the upper boundary hit count is
exported in the memory.failcnt file, but an OOM event count has to
be manually counted by listening to memory.oom_control events, and
lower boundary / soft limit events have to be counted by first
setting a threshold for that value and then counting those events.
Also, usage and limit files encode their units in the filename.
That makes the filenames very long, even though this is not
information that a user needs to be reminded of every time they
type out those names.
To address these naming issues, as well as to signal clearly that
the new interface carries a new configuration model, the naming
conventions in it necessarily differ from the old interface.
- The original limit files indicate the state of an unset limit with
a very high number, and a configured limit can be unset by echoing
-1 into those files. But that very high number is implementation
and architecture dependent and not very descriptive. And while -1
can be understood as an underflow into the highest possible value,
-2 or -10M etc. do not work, so it's not inconsistent.
memory.low, memory.high, and memory.max will use the string
"infinity" to indicate and set the highest possible value.
[akpm@linux-foundation.org: use seq_puts() for basic strings]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
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Henrik Austad
|
f595f76def |
Update of Documentation/cgroups/00-INDEX
unified-hierarchy.txt was added by
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Linus Torvalds
|
78a45c6f06 |
Merge branch 'akpm' (second patch-bomb from Andrew)
Merge second patchbomb from Andrew Morton: - the rest of MM - misc fs fixes - add execveat() syscall - new ratelimit feature for fault-injection - decompressor updates - ipc/ updates - fallocate feature creep - fsnotify cleanups - a few other misc things * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (99 commits) cgroups: Documentation: fix trivial typos and wrong paragraph numberings parisc: percpu: update comments referring to __get_cpu_var percpu: update local_ops.txt to reflect this_cpu operations percpu: remove __get_cpu_var and __raw_get_cpu_var macros fsnotify: remove destroy_list from fsnotify_mark fsnotify: unify inode and mount marks handling fallocate: create FAN_MODIFY and IN_MODIFY events mm/cma: make kmemleak ignore CMA regions slub: fix cpuset check in get_any_partial slab: fix cpuset check in fallback_alloc shmdt: use i_size_read() instead of ->i_size ipc/shm.c: fix overly aggressive shmdt() when calls span multiple segments ipc/msg: increase MSGMNI, remove scaling ipc/sem.c: increase SEMMSL, SEMMNI, SEMOPM ipc/sem.c: change memory barrier in sem_lock() to smp_rmb() lib/decompress.c: consistency of compress formats for kernel image decompress_bunzip2: off by one in get_next_block() usr/Kconfig: make initrd compression algorithm selection not expert fault-inject: add ratelimit option ratelimit: add initialization macro ... |
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SeongJae Park
|
29d293b600 |
cgroups: Documentation: fix trivial typos and wrong paragraph numberings
Signed-off-by: SeongJae Park <sj38.park@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Linus Torvalds
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823e334ecd |
Docs changes for the 3.19 merge window
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Johannes Weiner
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1306a85aed |
mm: embed the memcg pointer directly into struct page
Memory cgroups used to have 5 per-page pointers. To allow users to
disable that amount of overhead during runtime, those pointers were
allocated in a separate array, with a translation layer between them and
struct page.
There is now only one page pointer remaining: the memcg pointer, that
indicates which cgroup the page is associated with when charged. The
complexity of runtime allocation and the runtime translation overhead is
no longer justified to save that *potential* 0.19% of memory. With
CONFIG_SLUB, page->mem_cgroup actually sits in the doubleword padding
after the page->private member and doesn't even increase struct page,
and then this patch actually saves space. Remaining users that care can
still compile their kernels without CONFIG_MEMCG.
text data bss dec hex filename
8828345 1725264 983040 11536649 b00909 vmlinux.old
8827425 1725264 966656 11519345 afc571 vmlinux.new
[mhocko@suse.cz: update Documentation/cgroups/memory.txt]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Vladimir Davydov <vdavydov@parallels.com>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Johannes Weiner
|
5b1efc027c |
kernel: res_counter: remove the unused API
All memory accounting and limiting has been switched over to the lockless page counters. Bye, res_counter! [akpm@linux-foundation.org: update Documentation/cgroups/memory.txt] [mhocko@suse.cz: ditch the last remainings of res_counter] Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Vladimir Davydov <vdavydov@parallels.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Tejun Heo <tj@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Johannes Weiner
|
71f87bee38 |
mm: hugetlb_cgroup: convert to lockless page counters
Abandon the spinlock-protected byte counters in favor of the unlocked page counters in the hugetlb controller as well. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Vladimir Davydov <vdavydov@parallels.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Tejun Heo <tj@kernel.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Johannes Weiner
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3e32cb2e0a |
mm: memcontrol: lockless page counters
Memory is internally accounted in bytes, using spinlock-protected 64-bit
counters, even though the smallest accounting delta is a page. The
counter interface is also convoluted and does too many things.
Introduce a new lockless word-sized page counter API, then change all
memory accounting over to it. The translation from and to bytes then only
happens when interfacing with userspace.
The removed locking overhead is noticable when scaling beyond the per-cpu
charge caches - on a 4-socket machine with 144-threads, the following test
shows the performance differences of 288 memcgs concurrently running a
page fault benchmark:
vanilla:
18631648.500498 task-clock (msec) # 140.643 CPUs utilized ( +- 0.33% )
1,380,638 context-switches # 0.074 K/sec ( +- 0.75% )
24,390 cpu-migrations # 0.001 K/sec ( +- 8.44% )
1,843,305,768 page-faults # 0.099 M/sec ( +- 0.00% )
50,134,994,088,218 cycles # 2.691 GHz ( +- 0.33% )
<not supported> stalled-cycles-frontend
<not supported> stalled-cycles-backend
8,049,712,224,651 instructions # 0.16 insns per cycle ( +- 0.04% )
1,586,970,584,979 branches # 85.176 M/sec ( +- 0.05% )
1,724,989,949 branch-misses # 0.11% of all branches ( +- 0.48% )
132.474343877 seconds time elapsed ( +- 0.21% )
lockless:
12195979.037525 task-clock (msec) # 133.480 CPUs utilized ( +- 0.18% )
832,850 context-switches # 0.068 K/sec ( +- 0.54% )
15,624 cpu-migrations # 0.001 K/sec ( +- 10.17% )
1,843,304,774 page-faults # 0.151 M/sec ( +- 0.00% )
32,811,216,801,141 cycles # 2.690 GHz ( +- 0.18% )
<not supported> stalled-cycles-frontend
<not supported> stalled-cycles-backend
9,999,265,091,727 instructions # 0.30 insns per cycle ( +- 0.10% )
2,076,759,325,203 branches # 170.282 M/sec ( +- 0.12% )
1,656,917,214 branch-misses # 0.08% of all branches ( +- 0.55% )
91.369330729 seconds time elapsed ( +- 0.45% )
On top of improved scalability, this also gets rid of the icky long long
types in the very heart of memcg, which is great for 32 bit and also makes
the code a lot more readable.
Notable differences between the old and new API:
- res_counter_charge() and res_counter_charge_nofail() become
page_counter_try_charge() and page_counter_charge() resp. to match
the more common kernel naming scheme of try_do()/do()
- res_counter_uncharge_until() is only ever used to cancel a local
counter and never to uncharge bigger segments of a hierarchy, so
it's replaced by the simpler page_counter_cancel()
- res_counter_set_limit() is replaced by page_counter_limit(), which
expects its callers to serialize against themselves
- res_counter_memparse_write_strategy() is replaced by
page_counter_limit(), which rounds down to the nearest page size -
rather than up. This is more reasonable for explicitely requested
hard upper limits.
- to keep charging light-weight, page_counter_try_charge() charges
speculatively, only to roll back if the result exceeds the limit.
Because of this, a failing bigger charge can temporarily lock out
smaller charges that would otherwise succeed. The error is bounded
to the difference between the smallest and the biggest possible
charge size, so for memcg, this means that a failing THP charge can
send base page charges into reclaim upto 2MB (4MB) before the limit
would have been reached. This should be acceptable.
[akpm@linux-foundation.org: add includes for WARN_ON_ONCE and memparse]
[akpm@linux-foundation.org: add includes for WARN_ON_ONCE, memparse, strncmp, and PAGE_SIZE]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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SeongJae Park
|
845502d263 |
cgroups: Documentation: fix wrong cgroupfs paths
Few paths used as example to describe cgroupfs usage have been wrong
from
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Zefan Li
|
2ad654bc5e |
cpuset: PF_SPREAD_PAGE and PF_SPREAD_SLAB should be atomic flags
When we change cpuset.memory_spread_{page,slab}, cpuset will flip
PF_SPREAD_{PAGE,SLAB} bit of tsk->flags for each task in that cpuset.
This should be done using atomic bitops, but currently we don't,
which is broken.
Tetsuo reported a hard-to-reproduce kernel crash on RHEL6, which happened
when one thread tried to clear PF_USED_MATH while at the same time another
thread tried to flip PF_SPREAD_PAGE/PF_SPREAD_SLAB. They both operate on
the same task.
Here's the full report:
https://lkml.org/lkml/2014/9/19/230
To fix this, we make PF_SPREAD_PAGE and PF_SPREAD_SLAB atomic flags.
v4:
- updated mm/slab.c. (Fengguang Wu)
- updated Documentation.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Cc: Kees Cook <keescook@chromium.org>
Fixes:
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Johannes Weiner
|
0a31bc97c8 |
mm: memcontrol: rewrite uncharge API
The memcg uncharging code that is involved towards the end of a page's lifetime - truncation, reclaim, swapout, migration - is impressively complicated and fragile. Because anonymous and file pages were always charged before they had their page->mapping established, uncharges had to happen when the page type could still be known from the context; as in unmap for anonymous, page cache removal for file and shmem pages, and swap cache truncation for swap pages. However, these operations happen well before the page is actually freed, and so a lot of synchronization is necessary: - Charging, uncharging, page migration, and charge migration all need to take a per-page bit spinlock as they could race with uncharging. - Swap cache truncation happens during both swap-in and swap-out, and possibly repeatedly before the page is actually freed. This means that the memcg swapout code is called from many contexts that make no sense and it has to figure out the direction from page state to make sure memory and memory+swap are always correctly charged. - On page migration, the old page might be unmapped but then reused, so memcg code has to prevent untimely uncharging in that case. Because this code - which should be a simple charge transfer - is so special-cased, it is not reusable for replace_page_cache(). But now that charged pages always have a page->mapping, introduce mem_cgroup_uncharge(), which is called after the final put_page(), when we know for sure that nobody is looking at the page anymore. For page migration, introduce mem_cgroup_migrate(), which is called after the migration is successful and the new page is fully rmapped. Because the old page is no longer uncharged after migration, prevent double charges by decoupling the page's memcg association (PCG_USED and pc->mem_cgroup) from the page holding an actual charge. The new bits PCG_MEM and PCG_MEMSW represent the respective charges and are transferred to the new page during migration. mem_cgroup_migrate() is suitable for replace_page_cache() as well, which gets rid of mem_cgroup_replace_page_cache(). However, care needs to be taken because both the source and the target page can already be charged and on the LRU when fuse is splicing: grab the page lock on the charge moving side to prevent changing pc->mem_cgroup of a page under migration. Also, the lruvecs of both pages change as we uncharge the old and charge the new during migration, and putback may race with us, so grab the lru lock and isolate the pages iff on LRU to prevent races and ensure the pages are on the right lruvec afterward. Swap accounting is massively simplified: because the page is no longer uncharged as early as swap cache deletion, a new mem_cgroup_swapout() can transfer the page's memory+swap charge (PCG_MEMSW) to the swap entry before the final put_page() in page reclaim. Finally, page_cgroup changes are now protected by whatever protection the page itself offers: anonymous pages are charged under the page table lock, whereas page cache insertions, swapin, and migration hold the page lock. Uncharging happens under full exclusion with no outstanding references. Charging and uncharging also ensure that the page is off-LRU, which serializes against charge migration. Remove the very costly page_cgroup lock and set pc->flags non-atomically. [mhocko@suse.cz: mem_cgroup_charge_statistics needs preempt_disable] [vdavydov@parallels.com: fix flags definition] Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Hugh Dickins <hughd@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vladimir Davydov <vdavydov@parallels.com> Tested-by: Jet Chen <jet.chen@intel.com> Acked-by: Michal Hocko <mhocko@suse.cz> Tested-by: Felipe Balbi <balbi@ti.com> Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Johannes Weiner
|
00501b531c |
mm: memcontrol: rewrite charge API
These patches rework memcg charge lifetime to integrate more naturally
with the lifetime of user pages. This drastically simplifies the code and
reduces charging and uncharging overhead. The most expensive part of
charging and uncharging is the page_cgroup bit spinlock, which is removed
entirely after this series.
Here are the top-10 profile entries of a stress test that reads a 128G
sparse file on a freshly booted box, without even a dedicated cgroup (i.e.
executing in the root memcg). Before:
15.36% cat [kernel.kallsyms] [k] copy_user_generic_string
13.31% cat [kernel.kallsyms] [k] memset
11.48% cat [kernel.kallsyms] [k] do_mpage_readpage
4.23% cat [kernel.kallsyms] [k] get_page_from_freelist
2.38% cat [kernel.kallsyms] [k] put_page
2.32% cat [kernel.kallsyms] [k] __mem_cgroup_commit_charge
2.18% kswapd0 [kernel.kallsyms] [k] __mem_cgroup_uncharge_common
1.92% kswapd0 [kernel.kallsyms] [k] shrink_page_list
1.86% cat [kernel.kallsyms] [k] __radix_tree_lookup
1.62% cat [kernel.kallsyms] [k] __pagevec_lru_add_fn
After:
15.67% cat [kernel.kallsyms] [k] copy_user_generic_string
13.48% cat [kernel.kallsyms] [k] memset
11.42% cat [kernel.kallsyms] [k] do_mpage_readpage
3.98% cat [kernel.kallsyms] [k] get_page_from_freelist
2.46% cat [kernel.kallsyms] [k] put_page
2.13% kswapd0 [kernel.kallsyms] [k] shrink_page_list
1.88% cat [kernel.kallsyms] [k] __radix_tree_lookup
1.67% cat [kernel.kallsyms] [k] __pagevec_lru_add_fn
1.39% kswapd0 [kernel.kallsyms] [k] free_pcppages_bulk
1.30% cat [kernel.kallsyms] [k] kfree
As you can see, the memcg footprint has shrunk quite a bit.
text data bss dec hex filename
37970 9892 400 48262 bc86 mm/memcontrol.o.old
35239 9892 400 45531 b1db mm/memcontrol.o
This patch (of 4):
The memcg charge API charges pages before they are rmapped - i.e. have an
actual "type" - and so every callsite needs its own set of charge and
uncharge functions to know what type is being operated on. Worse,
uncharge has to happen from a context that is still type-specific, rather
than at the end of the page's lifetime with exclusive access, and so
requires a lot of synchronization.
Rewrite the charge API to provide a generic set of try_charge(),
commit_charge() and cancel_charge() transaction operations, much like
what's currently done for swap-in:
mem_cgroup_try_charge() attempts to reserve a charge, reclaiming
pages from the memcg if necessary.
mem_cgroup_commit_charge() commits the page to the charge once it
has a valid page->mapping and PageAnon() reliably tells the type.
mem_cgroup_cancel_charge() aborts the transaction.
This reduces the charge API and enables subsequent patches to
drastically simplify uncharging.
As pages need to be committed after rmap is established but before they
are added to the LRU, page_add_new_anon_rmap() must stop doing LRU
additions again. Revive lru_cache_add_active_or_unevictable().
[hughd@google.com: fix shmem_unuse]
[hughd@google.com: Add comments on the private use of -EAGAIN]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
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Tejun Heo
|
a8ddc8215e |
cgroup: distinguish the default and legacy hierarchies when handling cftypes
Until now, cftype arrays carried files for both the default and legacy
hierarchies and the files which needed to be used on only one of them
were flagged with either CFTYPE_ONLY_ON_DFL or CFTYPE_INSANE. This
gets confusing very quickly and we may end up exposing interface files
to the default hierarchy without thinking it through.
This patch makes cgroup core provide separate sets of interfaces for
cftype handling so that the cftypes for the default and legacy
hierarchies are clearly distinguished. The previous two patches
renamed the existing ones so that they clearly indicate that they're
for the legacy hierarchies. This patch adds the interface for the
default hierarchy and apply them selectively depending on the
hierarchy type.
* cftypes added through cgroup_subsys->dfl_cftypes and
cgroup_add_dfl_cftypes() only show up on the default hierarchy.
* cftypes added through cgroup_subsys->legacy_cftypes and
cgroup_add_legacy_cftypes() only show up on the legacy hierarchies.
* cgroup_subsys->dfl_cftypes and ->legacy_cftypes can point to the
same array for the cases where the interface files are identical on
both types of hierarchies.
* This makes all the existing subsystem interface files legacy-only by
default and all subsystems will have no interface file created when
enabled on the default hierarchy. Each subsystem should explicitly
review and compose the interface for the default hierarchy.
* A boot param "cgroup__DEVEL__legacy_files_on_dfl" is added which
makes subsystems which haven't decided the interface files for the
default hierarchy to present the legacy files on the default
hierarchy so that its behavior on the default hierarchy can be
tested. As the awkward name suggests, this is for development only.
* memcg's CFTYPE_INSANE on "use_hierarchy" is noop now as the whole
array isn't used on the default hierarchy. The flag is removed.
v2: Updated documentation for cgroup__DEVEL__legacy_files_on_dfl.
v3: Clear CFTYPE_ONLY_ON_DFL and CFTYPE_INSANE when cfts are removed
as suggested by Li.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Aristeu Rozanski <aris@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
|
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Tejun Heo
|
af0ba6789c |
cgroup: implement cgroup_subsys->depends_on
Currently, the blkio subsystem attributes all of writeback IOs to the root. One of the issues is that there's no way to tell who originated a writeback IO from block layer. Those IOs are usually issued asynchronously from a task which didn't have anything to do with actually generating the dirty pages. The memory subsystem, when enabled, already keeps track of the ownership of each dirty page and it's desirable for blkio to piggyback instead of adding its own per-page tag. blkio piggybacking on memory is an implementation detail which preferably should be handled automatically without requiring explicit userland action. To achieve that, this patch implements cgroup_subsys->depends_on which contains the mask of subsystems which should be enabled together when the subsystem is enabled. The previous patches already implemented the support for enabled but invisible subsystems and cgroup_subsys->depends_on can be easily implemented by updating cgroup_refresh_child_subsys_mask() so that it calculates cgroup->child_subsys_mask considering cgroup_subsys->depends_on of the explicitly enabled subsystems. Documentation/cgroups/unified-hierarchy.txt is updated to explain that subsystems may not become immediately available after being unused from userland and that dependency could be a factor in it. As subsystems may already keep residual references, this doesn't significantly change how subsystem rebinding can be used. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> |
||
|
Tejun Heo
|
b4536f0cab |
cgroup: implement cgroup_subsys->css_reset()
cgroup is implementing support for subsystem dependency which would require a way to enable a subsystem even when it's not directly configured through "cgroup.subtree_control". The previous patches added support for explicitly and implicitly enabled subsystems and showing/hiding their interface files. An explicitly enabled subsystem may become implicitly enabled if it's turned off through "cgroup.subtree_control" but there are subsystems depending on it. In such cases, the subsystem, as it's turned off when seen from userland, shouldn't enforce any resource control. Also, the subsystem may be explicitly turned on later again and its interface files should be as close to the intial state as possible. This patch adds cgroup_subsys->css_reset() which is invoked when a css is hidden. The callback should disable resource control and reset the state to the vanilla state. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> |
||
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Linus Torvalds
|
14208b0ec5 |
Merge branch 'for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup updates from Tejun Heo:
"A lot of activities on cgroup side. Heavy restructuring including
locking simplification took place to improve the code base and enable
implementation of the unified hierarchy, which currently exists behind
a __DEVEL__ mount option. The core support is mostly complete but
individual controllers need further work. To explain the design and
rationales of the the unified hierarchy
Documentation/cgroups/unified-hierarchy.txt
is added.
Another notable change is css (cgroup_subsys_state - what each
controller uses to identify and interact with a cgroup) iteration
update. This is part of continuing updates on css object lifetime and
visibility. cgroup started with reference count draining on removal
way back and is now reaching a point where csses behave and are
iterated like normal refcnted objects albeit with some complexities to
allow distinguishing the state where they're being deleted. The css
iteration update isn't taken advantage of yet but is planned to be
used to simplify memcg significantly"
* 'for-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (77 commits)
cgroup: disallow disabled controllers on the default hierarchy
cgroup: don't destroy the default root
cgroup: disallow debug controller on the default hierarchy
cgroup: clean up MAINTAINERS entries
cgroup: implement css_tryget()
device_cgroup: use css_has_online_children() instead of has_children()
cgroup: convert cgroup_has_live_children() into css_has_online_children()
cgroup: use CSS_ONLINE instead of CGRP_DEAD
cgroup: iterate cgroup_subsys_states directly
cgroup: introduce CSS_RELEASED and reduce css iteration fallback window
cgroup: move cgroup->serial_nr into cgroup_subsys_state
cgroup: link all cgroup_subsys_states in their sibling lists
cgroup: move cgroup->sibling and ->children into cgroup_subsys_state
cgroup: remove cgroup->parent
device_cgroup: remove direct access to cgroup->children
memcg: update memcg_has_children() to use css_next_child()
memcg: remove tasks/children test from mem_cgroup_force_empty()
cgroup: remove css_parent()
cgroup: skip refcnting on normal root csses and cgrp_dfl_root self css
cgroup: use cgroup->self.refcnt for cgroup refcnting
...
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Michal Hocko
|
688eb988d1 |
vmscan: memcg: always use swappiness of the reclaimed memcg
Memory reclaim always uses swappiness of the reclaim target memcg (origin of the memory pressure) or vm_swappiness for global memory reclaim. This behavior was consistent (except for difference between global and hard limit reclaim) because swappiness was enforced to be consistent within each memcg hierarchy. After "mm: memcontrol: remove hierarchy restrictions for swappiness and oom_control" each memcg can have its own swappiness independent of hierarchical parents, though, so the consistency guarantee is gone. This can lead to an unexpected behavior. Say that a group is explicitly configured to not swapout by memory.swappiness=0 but its memory gets swapped out anyway when the memory pressure comes from its parent with a It is also unexpected that the knob is meaningless without setting the hard limit which would trigger the reclaim and enforce the swappiness. There are setups where the hard limit is configured higher in the hierarchy by an administrator and children groups are under control of somebody else who is interested in the swapout behavior but not necessarily about the memory limit. From a semantic point of view swappiness is an attribute defining anon vs. file proportional scanning of LRU which is memcg specific (unlike charges which are propagated up the hierarchy) so it should be applied to the particular memcg's LRU regardless where the memory pressure comes from. This patch removes vmscan_swappiness() and stores the swappiness into the scan_control structure. mem_cgroup_swappiness is then used to provide the correct value before shrink_lruvec is called. The global vm_swappiness is used for the root memcg. [hughd@google.com: oopses immediately when booted with cgroup_disable=memory] Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Vladimir Davydov
|
2ee0646870 |
Documentation/memcg: warn about incomplete kmemcg state
Kmemcg is currently under development and lacks some important features. In particular, it does not have support of kmem reclaim on memory pressure inside cgroup, which practically makes it unusable in real life. Let's warn about it in both Kconfig and Documentation to prevent complaints arising. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Johannes Weiner
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3dae7fec5e |
mm: memcontrol: remove hierarchy restrictions for swappiness and oom_control
Per-memcg swappiness and oom killing can currently not be tweaked on a memcg that is part of a hierarchy, but not the root of that hierarchy. Users have complained that they can't configure this when they turned on hierarchy mode. In fact, with hierarchy mode becoming the default, this restriction disables the tunables entirely. But there is no good reason for this restriction. The settings for swappiness and OOM killing are taken from whatever memcg whose limit triggered reclaim and OOM invocation, regardless of its position in the hierarchy tree. Allow setting swappiness on any group. The knob on the root memcg already reads the global VM swappiness, make it writable as well. Allow disabling the OOM killer on any non-root memcg. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Tejun Heo <tj@kernel.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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Michal Hocko
|
f61c42a7d9 |
memcg: remove tasks/children test from mem_cgroup_force_empty()
Tejun has correctly pointed out that tasks/children test in mem_cgroup_force_empty is not correct because there is no other locking which preserves this state throughout the rest of the function so both new tasks can join the group or new children groups can be added while somebody is writing to memory.force_empty. A new task would break mem_cgroup_reparent_charges expectation that all failures as described by mem_cgroup_force_empty_list are temporal and there is no way out. The main use case for the knob as described by Documentation/cgroups/memory.txt is to: " The typical use case for this interface is before calling rmdir(). Because rmdir() moves all pages to parent, some out-of-use page caches can be moved to the parent. If you want to avoid that, force_empty will be useful. " This means that reparenting is not really required as rmdir will reparent pages implicitly from the safe context. If we remove it from mem_cgroup_force_empty then we are safe even with existing tasks because the number of reclaim attempts is bounded. Moreover the knob still does what the documentation claims (modulo reparenting which doesn't make any difference) and users might expect. Longterm we want to deprecate the whole knob and put the reparented pages to the tail of parent LRU during cgroup removal. tj: Removed unused variable @cgrp from mem_cgroup_force_empty() Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org> |
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Tejun Heo
|
6573157800 |
cgroup: add documentation about unified hierarchy
Unified hierarchy will be the new version of cgroup interface. This patch adds Documentation/cgroups/unified-hierarchy.txt which describes the design and rationales of unified hierarchy. v2: Grammatical updates as per Randy Dunlap's review. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Randy Dunlap <rdunlap@infradead.org> |
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Michal Hocko
|
d715ae08f2 |
memcg: rename high level charging functions
mem_cgroup_newpage_charge is used only for charging anonymous memory so it is better to rename it to mem_cgroup_charge_anon. mem_cgroup_cache_charge is used for file backed memory so rename it to mem_cgroup_charge_file. Signed-off-by: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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David Rientjes
|
539a13b47e |
res_counter: remove interface for locked charging and uncharging
The res_counter_{charge,uncharge}_locked() variants are not used in the
kernel outside of the resource counter code itself, so remove the
interface.
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Jianguo Wu <wujianguo@huawei.com>
Cc: Tim Hockin <thockin@google.com>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds
|
b399c46ea0 |
Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab: - a new jpeg codec driver for Samsung Exynos (jpeg-hw-exynos4) - a new dvb frontend for ds2103 chipset (m88ds2103) - a new sensor driver for Samsung S5K5BAF UXGA (s5k5baf) - new drivers for R-Car VSP1 - a new radio driver: radio-raremono - a new tuner driver for ts2022 chipset (m88ts2022) - the analog part of em28xx is now a separate module that only load/runs if the device is not a pure digital TV device - added a staging driver for bcm2048 radio devices - the omap 2 video driver (omap24xx) was moved to staging. This driver is for an old hardware and uses a deprecated Kernel internal API. If nobody cares enough to fix it, it would be removed on a couple Kernel releases - the sn9c102 driver was moved to staging. This driver was replaced by gspca, and disabled on some distros, as almost all devices are known to work properly with gspca. It should be removed from kernel on a couple Kernel releases - lots of driver fixes, improvements and cleanups * 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (421 commits) [media] media: v4l2-dev: fix video device index assignment [media] rc-core: reuse device numbers [media] em28xx-cards: properly initialize the device bitmap [media] Staging: media: Fix line length exceeding 80 characters in as102_drv.c [media] Staging: media: Fix line length exceeding 80 characters in as102_fe.c [media] Staging: media: Fix quoted string split across line in as102_fe.c [media] media: st-rc: Add reset support [media] m2m-deinterlace: fix allocated struct type [media] radio-usb-si4713: fix sparse non static symbol warnings [media] em28xx-audio: remove needless check before usb_free_coherent() [media] au0828: Fix sparse non static symbol warning Revert "[media] go7007-usb: only use go->dev after allocated" [media] em28xx-audio: provide an error code when URB submit fails [media] em28xx: fix check for audio only usb interfaces when changing the usb alternate setting [media] em28xx: fix usb alternate setting for analog and digital video endpoints > 0 [media] em28xx: make 'em28xx_ctrl_ops' static em28xx-alsa: Fix error patch for init/fini [media] em28xx-audio: flush work at .fini [media] drxk: remove the option to load firmware asynchronously [media] em28xx: adjust period size at runtime ... |
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Linus Torvalds
|
4ba9920e5e |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
1) BPF debugger and asm tool by Daniel Borkmann.
2) Speed up create/bind in AF_PACKET, also from Daniel Borkmann.
3) Correct reciprocal_divide and update users, from Hannes Frederic
Sowa and Daniel Borkmann.
4) Currently we only have a "set" operation for the hw timestamp socket
ioctl, add a "get" operation to match. From Ben Hutchings.
5) Add better trace events for debugging driver datapath problems, also
from Ben Hutchings.
6) Implement auto corking in TCP, from Eric Dumazet. Basically, if we
have a small send and a previous packet is already in the qdisc or
device queue, defer until TX completion or we get more data.
7) Allow userspace to manage ipv6 temporary addresses, from Jiri Pirko.
8) Add a qdisc bypass option for AF_PACKET sockets, from Daniel
Borkmann.
9) Share IP header compression code between Bluetooth and IEEE802154
layers, from Jukka Rissanen.
10) Fix ipv6 router reachability probing, from Jiri Benc.
11) Allow packets to be captured on macvtap devices, from Vlad Yasevich.
12) Support tunneling in GRO layer, from Jerry Chu.
13) Allow bonding to be configured fully using netlink, from Scott
Feldman.
14) Allow AF_PACKET users to obtain the VLAN TPID, just like they can
already get the TCI. From Atzm Watanabe.
15) New "Heavy Hitter" qdisc, from Terry Lam.
16) Significantly improve the IPSEC support in pktgen, from Fan Du.
17) Allow ipv4 tunnels to cache routes, just like sockets. From Tom
Herbert.
18) Add Proportional Integral Enhanced packet scheduler, from Vijay
Subramanian.
19) Allow openvswitch to mmap'd netlink, from Thomas Graf.
20) Key TCP metrics blobs also by source address, not just destination
address. From Christoph Paasch.
21) Support 10G in generic phylib. From Andy Fleming.
22) Try to short-circuit GRO flow compares using device provided RX
hash, if provided. From Tom Herbert.
The wireless and netfilter folks have been busy little bees too.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2064 commits)
net/cxgb4: Fix referencing freed adapter
ipv6: reallocate addrconf router for ipv6 address when lo device up
fib_frontend: fix possible NULL pointer dereference
rtnetlink: remove IFLA_BOND_SLAVE definition
rtnetlink: remove check for fill_slave_info in rtnl_have_link_slave_info
qlcnic: update version to 5.3.55
qlcnic: Enhance logic to calculate msix vectors.
qlcnic: Refactor interrupt coalescing code for all adapters.
qlcnic: Update poll controller code path
qlcnic: Interrupt code cleanup
qlcnic: Enhance Tx timeout debugging.
qlcnic: Use bool for rx_mac_learn.
bonding: fix u64 division
rtnetlink: add missing IFLA_BOND_AD_INFO_UNSPEC
sfc: Use the correct maximum TX DMA ring size for SFC9100
Add Shradha Shah as the sfc driver maintainer.
net/vxlan: Share RX skb de-marking and checksum checks with ovs
tulip: cleanup by using ARRAY_SIZE()
ip_tunnel: clear IPCB in ip_tunnel_xmit() in case dst_link_failure() is called
net/cxgb4: Don't retrieve stats during recovery
...
|
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Daniel Borkmann
|
82a37132f3 |
netfilter: x_tables: lightweight process control group matching
It would be useful e.g. in a server or desktop environment to have a facility in the notion of fine-grained "per application" or "per application group" firewall policies. Probably, users in the mobile, embedded area (e.g. Android based) with different security policy requirements for application groups could have great benefit from that as well. For example, with a little bit of configuration effort, an admin could whitelist well-known applications, and thus block otherwise unwanted "hard-to-track" applications like [1] from a user's machine. Blocking is just one example, but it is not limited to that, meaning we can have much different scenarios/policies that netfilter allows us than just blocking, e.g. fine grained settings where applications are allowed to connect/send traffic to, application traffic marking/conntracking, application-specific packet mangling, and so on. Implementation of PID-based matching would not be appropriate as they frequently change, and child tracking would make that even more complex and ugly. Cgroups would be a perfect candidate for accomplishing that as they associate a set of tasks with a set of parameters for one or more subsystems, in our case the netfilter subsystem, which, of course, can be combined with other cgroup subsystems into something more complex if needed. As mentioned, to overcome this constraint, such processes could be placed into one or multiple cgroups where different fine-grained rules can be defined depending on the application scenario, while e.g. everything else that is not part of that could be dropped (or vice versa), thus making life harder for unwanted processes to communicate to the outside world. So, we make use of cgroups here to track jobs and limit their resources in terms of iptables policies; in other words, limiting, tracking, etc what they are allowed to communicate. In our case we're working on outgoing traffic based on which local socket that originated from. Also, one doesn't even need to have an a-prio knowledge of the application internals regarding their particular use of ports or protocols. Matching is *extremly* lightweight as we just test for the sk_classid marker of sockets, originating from net_cls. net_cls and netfilter do not contradict each other; in fact, each construct can live as standalone or they can be used in combination with each other, which is perfectly fine, plus it serves Tejun's requirement to not introduce a new cgroups subsystem. Through this, we result in a very minimal and efficient module, and don't add anything except netfilter code. One possible, minimal usage example (many other iptables options can be applied obviously): 1) Configuring cgroups if not already done, e.g.: mkdir /sys/fs/cgroup/net_cls mount -t cgroup -o net_cls net_cls /sys/fs/cgroup/net_cls mkdir /sys/fs/cgroup/net_cls/0 echo 1 > /sys/fs/cgroup/net_cls/0/net_cls.classid (resp. a real flow handle id for tc) 2) Configuring netfilter (iptables-nftables), e.g.: iptables -A OUTPUT -m cgroup ! --cgroup 1 -j DROP 3) Running applications, e.g.: ping 208.67.222.222 <pid:1799> echo 1799 > /sys/fs/cgroup/net_cls/0/tasks 64 bytes from 208.67.222.222: icmp_seq=44 ttl=49 time=11.9 ms [...] ping 208.67.220.220 <pid:1804> ping: sendmsg: Operation not permitted [...] echo 1804 > /sys/fs/cgroup/net_cls/0/tasks 64 bytes from 208.67.220.220: icmp_seq=89 ttl=56 time=19.0 ms [...] Of course, real-world deployments would make use of cgroups user space toolsuite, or own custom policy daemons dynamically moving applications from/to various cgroups. [1] http://www.blackhat.com/presentations/bh-europe-06/bh-eu-06-biondi/bh-eu-06-biondi-up.pdf Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: cgroups@vger.kernel.org Acked-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> |
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Masanari Iida
|
8173d5a495 |
doc: cgroups: Fix typo in doc/cgroups
Correct spelling typo in memory.txt and resource_counter.txt Signed-off-by: Masanari Iida <standby24x7@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org> |