linux-toradex.git/Documentation/ABI/testing/sysfs-kernel-slab, branch master

doc: Move SLUB documentation to the admin guide

2025-06-18T11:06:26+00:00

This section is supposed to be for internal documentation, while the
document is advice for sysadmins.  Move it to the appropriate place.

Signed-off-by: Matthew Wilcox (Oracle) 
Acked-by: Harry Yoo 
Link: https://patch.msgid.link/20250611155916.2579160-2-willy@infradead.org
Signed-off-by: Vlastimil Babka

Update Christoph's Email address and make it consistent

2025-05-13T06:50:31+00:00

Use cl@gentwo.org throughout and remove the old email addresses.

Link: https://lkml.kernel.org/r/8b962f57-4d98-cbb0-cd82-b6ba456733e8@gentwo.org
Signed-off-by: Christoph Lameter 
Signed-off-by: Andrew Morton

docs: rename Documentation/vm to Documentation/mm

2022-06-27T19:52:53+00:00

so it will be consistent with code mm directory and with
Documentation/admin-guide/mm and won't be confused with virtual machines.

Signed-off-by: Mike Rapoport 
Suggested-by: Matthew Wilcox 
Tested-by: Ira Weiny 
Acked-by: Jonathan Corbet 
Acked-by: Wu XiangCheng

ABI: sysfs-kernel-slab: Document some stats

2021-09-28T10:48:15+00:00

Document three slab stats that were added in 2011 and 2017.

Fixes: 49e2258586b4 ("slub: per cpu cache for partial pages")
Fixes: 8eb8284b4129 ("usercopy: Prepare for usercopy whitelisting")

Signed-off-by: Mauro Carvalho Chehab 
Link: https://lore.kernel.org/r/8960435734c5aa918568ce7891171448c4d68709.1632750608.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman

ABI: sysfs-kernel-slab: use a wildcard for the cache name

2021-09-21T16:31:15+00:00

the "cache" part of the description is actually a wildcard,
as, in practice, this will use per-subsystem names:

    /sys/kernel/slab/Acpi-Namespace/align
    /sys/kernel/slab/Acpi-Operand/align
    /sys/kernel/slab/Acpi-Parse/align
...
    /sys/kernel/slab/zswap_entry/align

Signed-off-by: Mauro Carvalho Chehab 
Link: https://lore.kernel.org/r/64095cc0a38d0f675ab798d4f04d8631674b59f7.1631782432.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman

docs: ABI: cleanup several ABI documents

2020-10-30T12:14:29+00:00

There are some ABI documents that, while they don't generate
any warnings, they have issues when parsed by get_abi.pl script
on its output result.

Address them, in order to provide a clean output.

Reviewed-by: Tom Rix  # for fpga-manager
Reviewed-By: Kajol Jain # for sysfs-bus-event_source-devices-hv_gpci and sysfs-bus-event_source-devices-hv_24x7
Acked-by: Jonathan Cameron  #for IIO
Acked-by: Oded Gabbay  # for Habanalabs
Acked-by: Vaibhav Jain  # for sysfs-bus-papr-pmem
Acked-by: Cezary Rojewski  # for catpt
Acked-by: Suzuki K Poulose 
Acked-by: Ilya Dryomov  # for rbd
Acked-by: Jonathan Corbet 
Signed-off-by: Mauro Carvalho Chehab 
Link: https://lore.kernel.org/r/5bc78e5b68ed1e9e39135173857cb2e753be868f.1604042072.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman

mm, slab: extend slab/shrink to shrink all memcg caches

2019-09-24T22:54:07+00:00

Currently, a value of '1" is written to /sys/kernel/slab//shrink
file to shrink the slab by flushing out all the per-cpu slabs and free
slabs in partial lists.  This can be useful to squeeze out a bit more
memory under extreme condition as well as making the active object counts
in /proc/slabinfo more accurate.

This usually applies only to the root caches, as the SLUB_MEMCG_SYSFS_ON
option is usually not enabled and "slub_memcg_sysfs=1" not set.  Even if
memcg sysfs is turned on, it is too cumbersome and impractical to manage
all those per-memcg sysfs files in a real production system.

So there is no practical way to shrink memcg caches.  Fix this by enabling
a proper write to the shrink sysfs file of the root cache to scan all the
available memcg caches and shrink them as well.  For a non-root memcg
cache (when SLUB_MEMCG_SYSFS_ON or slub_memcg_sysfs is on), only that
cache will be shrunk when written.

On a 2-socket 64-core 256-thread arm64 system with 64k page after
a parallel kernel build, the the amount of memory occupied by slabs
before shrinking slabs were:

 # grep task_struct /proc/slabinfo
 task_struct        53137  53192   4288   61    4 : tunables    0    0
 0 : slabdata    872    872      0
 # grep "^S[lRU]" /proc/meminfo
 Slab:            3936832 kB
 SReclaimable:     399104 kB
 SUnreclaim:      3537728 kB

After shrinking slabs (by echoing "1" to all shrink files):

 # grep "^S[lRU]" /proc/meminfo
 Slab:            1356288 kB
 SReclaimable:     263296 kB
 SUnreclaim:      1092992 kB
 # grep task_struct /proc/slabinfo
 task_struct         2764   6832   4288   61    4 : tunables    0    0
 0 : slabdata    112    112      0

Link: http://lkml.kernel.org/r/20190723151445.7385-1-longman@redhat.com
Signed-off-by: Waiman Long 
Acked-by: Roman Gushchin 
Acked-by: Christoph Lameter 
Cc: Pekka Enberg 
Cc: David Rientjes 
Cc: Joonsoo Kim 
Cc: Michal Hocko 
Cc: Johannes Weiner 
Cc: Shakeel Butt 
Cc: Vladimir Davydov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

docs/vm: rename documentation files to .rst

2018-04-16T20:18:15+00:00

Signed-off-by: Mike Rapoport 
Signed-off-by: Jonathan Corbet

docs: fix locations of several documents that got moved

2016-10-24T10:12:35+00:00

The previous patch renamed several files that are cross-referenced
along the Kernel documentation. Adjust the links to point to
the right places.

Signed-off-by: Mauro Carvalho Chehab

slub: document setting min order with debug_guardpage_minorder > 0

2012-01-13T04:13:04+00:00

Acked-by: David Rientjes 
Cc: Pekka Enberg 
Cc: "Rafael J. Wysocki" 
Signed-off-by: Stanislaw Gruszka 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds