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12 commits

Author SHA1 Message Date
T.J. Mercier
47580ff76d Reapply "libprocessgroup: Remove ACgroupController_getMaxActivati..."
This reverts commit aeca8793f5.

Change-Id: I06e7e651f0cabfd43b50a278baf36f31f6061a8f
2024-10-08 23:42:54 +00:00
Priyanka Advani (xWF)
aeca8793f5 Revert "libprocessgroup: Remove ACgroupController_getMaxActivati..."
Revert submission 3212512

Reason for revert: Droidmonitor created revert due to b/372273614. Will be verifying through ABTD before submission.

Reverted changes: /q/submissionid:3212512

Change-Id: I0964d1300791334cdc9e98220324d934f7ba113e
2024-10-08 18:54:37 +00:00
T.J. Mercier
c31c5a75c8 libprocessgroup: Remove ACgroupController_getMaxActivationDepth
This was targeted for API 36 which doesn't exist yet, so this was never
released. Now that libprocessgroup does not use the libcgrouprc
interfaces, this can be removed.

Bug: 349105928
Bug: 359609093
Change-Id: I2ea466c9e8bc54bf9178fa74b45e88f26d3e4c69
2024-10-03 17:01:34 +00:00
T.J. Mercier
28b37f2704 libprocessgroup: Add MaxActivationDepth
Cgroup v2 controllers can be enabled in a subtree of the shared
hierarchy. That allows users to limit the number of cgroups with a
controller enabled to less than the total number of cgroups. [1]

There are costs for each cgroup. Kernel memory is used for each cgroup,
plus additional memory for each active controller in each cgroup. Some
kernel operations scale with the number of cgroups (with a given
controller enabled), so it can be desirable to minimize the number of
cgroups with that controller enabled.

This change allows each v2 controller configuration to specify a maximum
activation depth, past which the controller will not be activated deeper
in the Android cgroup v2 hierarchy. The hierarchy root is defined as
depth 0. MaxActivationDepth is the field name for this purpose for
controllers in the Controllers array under Cgroups2 in cgroups.json.

Here are two examples:

"MaxActivationDepth": 1
This will activate the controller in every per-application cgroup, but
not in the per-process cgroups below.

/sys/fs/cgroup                depth=0  active=true  (controller listed in cgroup.subtree_control)
/sys/fs/cgroup/uid_0          depth=1  active=true  (controller NOT listed in cgroup.subtree_control)
/sys/fs/cgroup/uid_0/pid_100  depth=2  active=false (controller NOT listed in cgroup.subtree_control)

This can also be used with
PRODUCT_CGROUP_V2_SYS_APP_ISOLATION_ENABLED := true.

"MaxActivationDepth": 1
This will activate the controller only at the app / system level, but
not in per-application cgroups below. This results in a total of only
3 cgroups with the controller enabled (root, apps, system).

/sys/fs/cgroup                         depth=0  active=true  (controller listed in cgroup.subtree_control)
/sys/fs/cgroup/apps                    depth=1  active=true  (controller NOT listed in cgroup.subtree_control)
/sys/fs/cgroup/apps/uid_10000          depth=2  active=false (controller NOT listed in cgroup.subtree_control)
/sys/fs/cgroup/apps/uid_10000/pid_100  depth=3  active=false (controller NOT listed in cgroup.subtree_control)

[1] https://www.kernel.org/doc/html/latest/admin-guide/cgroup-v2.html#enabling-and-disabling

Bug: 346584259
Test: Cuttlefish with memcg v2
Change-Id: I62109ea935261c51fc30b2054c4d28d0360f7985
2024-06-18 15:50:21 +00:00
Colin Cross
80e34e3017 Fix compiling libprocessgroup against musl
Include sys/cdefs.h before using __BEGIN_DECLS.

Bug: 190084016
Test: m USE_HOST_MUSL=true
Change-Id: Iac009275f7198476dd83ac70dbbc626b70f88ed1
2021-09-14 12:35:01 -07:00
Suren Baghdasaryan
7f19b1e6de libprocessgroup: introduce optional attribute for cgroup controllers
Memory cgroup controller is not used by high-end Android devices and is
disabled in Android kernels 5.10+, however Android Go devices still
require this controller.
Similarly schedtune controller is being replaced with cpu controller's
utilclamp feature, however some devices are using older kernels which
only support schedtune.
To prevent spamming logcat with errors we need a way to mark a
controller optional in such cases without removing it from
cgroups.json file.
Introduce "Optional" attribute to cgroup controller's cgroups.json
description to accomodate these cases. When an optional controller
fails to mount due to lack of support in the kernel it will log an
informational message without generating further errors.

Bug: 181866655
Test: boot and observe libprocessgroup messages in logcat
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Change-Id: Ib5bcfdd8d338704f3f9d8b326d8ddd88b67915a1
2021-03-11 17:42:30 +00:00
Jiyong Park
2d30fe48d4 Remove __ANDROID_API__ guards
__ANDROID_API__ guards are removed in favor of __INTRODUCED_IN macros.

Currently, __INTRODUCED_IN macro does nothing for these headers (it's
meaningful only to the headers processed by versioner which are limited
to binic headers). The plan is to make the macros to tag the declaration
with the availability attribute. Then, when the min_sdk_version of a
caller is set to an API level that is older than the API level of the
APIs, the compiler will provide them as weak symbols and enforce that
calling the APIs are guarded with a runtime check.

For now, these guards are preventing from making a build system change
to let __ANDROID_API__ track the min_sdk_version property instead of the
sdk_version property. With the build system change, __ANDROID_API__ will
suddenly drop for the native modules where min_sdk_version <
sdk_version, which is the case when the modules are included in APEXes.
As a result, some new APIs will be unavailable at build-time. Dropping
the hand-written guards fixes the problem.

Bug: 163288375
Test: m
Change-Id: If1cc6b9af410f536abe6d777c22711209fa76530
2021-01-12 20:50:27 +09:00
Marco Ballesio
f16f9417b0 libprocessgroup: support for cgroup v2 hierarchy
for a first implementation the cgroup v2 freezer controller will be used in a
way similar to cgroup v1, that is a single child group will hold all frozen
processes. Some adjustments are needed for the new structure.

- Add support for cgroup v2 syntax under procfs.
- Separate creation of a directory with ownership/mode changes to allow changes
    after mounting the cgroup kernfs root.
- Allow the creation of sub-groups under a cgroup v2 hierarchy.

Bug: 154548692
Test: manually verified that a proper cgroup v2 hierarchy is created and
accessible

Change-Id: I9af59e8214acaead3f520a94c95e75394c0df948
2020-06-10 09:14:00 -07:00
Suren Baghdasaryan
cee468fb79 Revive ACgroupController_getFlags LLNDK function to detect missing cgroups
ACgroupController_getFlags was reverted due to LLNDK breakage, however
it allows detection of cgroups that failed to mount in a more efficient
way. Revive the function as a weakly linked symbol to allow for it to
be missing in case older LLNDK library is being used with the new
system software. This effectively reverts the commit
aa1d54f0cc "Remove ACgroupController_getFlags to fix API breakage"'
except it declares ACgroupController_getFlags function as weak and
targets it for API level 30. If LLNKD library does not contain
ACgroupController_getFlags the behavior falls back to the current
way of identifying cgroups that failed to mount.

Test: build and verify correct operation with a missing cgroup
Change-Id: I9158ef53aba97972d41d71dd3396ac43796a7004
Merged-In: I9158ef53aba97972d41d71dd3396ac43796a7004
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
2020-01-29 17:24:06 +00:00
Suren Baghdasaryan
338260a467 Remove ACgroupController_getFlags to fix API breakage
Since ACgroupController_getFlags was introduced after LLNDK freeze it
causes media crashes due to missing symbol. Remove the new function and
re-implement cgroup controller detection to not require flags field but
instead check for its existence on the first access.

Bug: 135049992
Test: libcutils_test with and without CONFIG_CPUSETS enabled
Change-Id: I0220d6a926884dc22a7424d7d0a980c379c6f4eb
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
2019-06-17 16:46:23 +00:00
Suren Baghdasaryan
fa7a05fe5f libprocessgroup: add flags to indicate when a controller failed to mount
Controllers listed in cgroups.json file might fail to mount if kernel is
not configured to support them. We need a way to indicate whether a
controller was successfully mounted and is usable to avoid logging errors
and warnings when a controller that failed to mount is being used. Add
flags bitmask to cgrouprc controller descriptor and use a bit to indicate
that controller is successfully mounted. Modify cpusets_enabled() and
schedboost_enabled() functions to use this bit and report the actual
availability of the controller.

Bug: 124080437
Test: libcutils_test with cpuset and schedtune controllers disabled
Change-Id: I770cc39fe50465146e3205aacf77dc3c56923c5d
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
2019-05-21 10:03:21 -07:00
Yifan Hong
098323ba5b libprocessgroup: Add libcgrouprc
This module is an LL-NDK library that can be loaded by
modules that link to libprocessgroup (which is in VNDK).
This module defines APIs that reads cgroups.rc file
programatically. Internally, it uses libcgrouprc_format to
do so.

Test: builds
Bug: 123664216

Change-Id: I9c13c0528461758154e23cbab3a94ade7fb351ee
Merged-In: I9c13c0528461758154e23cbab3a94ade7fb351ee
2019-04-02 22:31:57 -07:00