Not boosting kill target's priority can cause priority inversion. Boost
its priority from the reaper thread right after sending a SIGKILL to
prevent priority inversion. Also, using normal priority to the victim
processes. Thus, they won't take too much CPU resource which preempt
UI or important processes.
Bug: 238495258
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Change-Id: I789ec402f038a1b48d25f62f859be69bbddfad16
Merged-In: Ib4665d3df62f58e36686ca134f9ae07836fd6945
Setting cpusets and priorities for the kill target involves fs operations
which can block on kernel internal locks. Doing that from lmkd main thread
context has the danger of blocking lmkd. With the introduction of the
reaper threads the time for the target to exit is not as critical since
its memory is freed by the reaper thread.
To prevent lmkd from being blocked, move setting cpuset for the kill
target into the reaper thread and remove priority setting logic with
heavy use of procfs reads.
Bug: 238495258
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Change-Id: I5defc6baa4ff1425d9835371b47a64e375ebac10
Merged-In: I5defc6baa4ff1425d9835371b47a64e375ebac10
pid_remove() is not a thread-safe function and can be called only from
the main thread. Calling it from the watchdog_callback() executed in the
context of the watchdog thread can cause a use-after-free failure if the
same record is being used by the main thread. Fix this issue by marking
the process record as invalid instead of destroying it. Later on invalid
records will be cleared in kill_one_process() called from the context of
the main thread.
Fixes: f8727745f9 ("lmkd: Remove process record after it is killed by lmkd watchdog")
Bug: 248448498
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Change-Id: I0c7776aea1518c17f0a29904a44b7fe8f33980ca
After lmkd watchdog kills a process, its record should be removed.
Bug: 243567425
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Change-Id: I70bb2a432df8088ebc9865fbc36b065738248d19
Fix the text of the warning when pthread_setschedparam fails to set
SCHED_OTHER scheduling policy for a reaper thread.
Bug: 237180716
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Change-Id: I1b04713d145f4f3c243f16f932c753f5b06d48e6
Reaper threads can take considerable time to free target's
memory running at RT priority that they inherit from LMKD.
This might prevent other critical tasks from being scheduled
while reaper threads are active.
Explicitly set reaper threads to run under normal scheduling
policy but set their nice value to ANDROID_PRIORITY_HIGHEST.
Bug: 237180716
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Change-Id: Idad817e698ae1d5ac6cee5aa3281c69c7e0d257f
Use the /sys/fs/cgroup/uid_%u/pid_%u path instead of
/dev/memcg/apps/uid_%u/pid_%u" if the memcg controller is mounted in the
v2 cgroup hierarchy. Skip the code that refers to memcg attributes that
only exist in the cgroup v1 hierarchy when using the v2 memcg. Complain
if it is attempted to use the old kill strategy in combination with
memcg v2 since only the new strategy is compatible with the v2 cgroup
hiearchy.
Bug: 213617178
Test: Tested lmkd inside the Cuttlefish emulator. Triggered an
Test: out-of-memory condition as follows:
Test: i=0; while [ $i -lt 16 ]; do dd if=/dev/zero of=/dev/null bs=1G count=1 & ((i++)) done
Test: That caused the following output to appear in logcat:
Test: 02-03 18:13:02.772 241 241 I lowmemorykiller: Kill 'com.android.packageinstaller' (3031), uid 10022, oom_score_adj 975 to free 29348kB rss, 21232kB swap; reason: min watermark is breached and swap is low (135016kB < 150384kB)
Test: 02-03 18:13:02.772 241 241 I killinfo: [3031,10022,975,0,29348,3,73644,98460,8,1000,33448,40220,1503848,135016,81720,1387040,27268,29520,50348,103164,20176,57664,0,0,0,519,103,5,0,21232,30016,0,2]
Test: From the kernel log:
Test: [ 302.834958] Out of memory: Killed process 3017 (ADB-JDWP Connec) total-vm:13522856kB, anon-rss:0kB, file-rss:0kB, shmem-rss:560kB, UID:10052 pgtables:1008kB oom_score_adj:975
Test: [ 303.223702] Out of memory: Killed process 2859 (HeapTaskDaemon) total-vm:13534452kB, anon-rss:0kB, file-rss:0kB, shmem-rss:560kB, UID:10051 pgtables:1060kB oom_score_adj:965
Test: [ 303.478833] Out of memory: Killed process 2816 (Signal Catcher) total-vm:13524108kB, anon-rss:0kB, file-rss:0kB, shmem-rss:564kB, UID:10073 pgtables:1016kB oom_score_adj:965
Test: [ 304.823796] Out of memory: Killed process 2438 (ReferenceQueueD) total-vm:13529180kB, anon-rss:0kB, file-rss:0kB, shmem-rss:568kB, UID:10015 pgtables:1056kB oom_score_adj:955
Test: [ 305.226728] Out of memory: Killed process 3126 (DefaultDispatch) total-vm:13532596kB, anon-rss:0kB, file-rss:0kB, shmem-rss:528kB, UID:10019 pgtables:1064kB oom_score_adj:945
Test: [ 305.935615] Out of memory: Killed process 2637 (Jit thread pool) total-vm:13523084kB, anon-rss:0kB, file-rss:0kB, shmem-rss:0kB, UID:10024 pgtables:1036kB oom_score_adj:935
Test: [ 307.055895] Out of memory: Killed process 2063 (HeapTaskDaemon) total-vm:13755876kB, anon-rss:0kB, file-rss:0kB, shmem-rss:11600kB, UID:10074 pgtables:1552kB oom_score_adj:0
Test: [ 307.398512] Out of memory: Killed process 2298 (rs.media.module) total-vm:13560404kB, anon-rss:12924kB, file-rss:0kB, shmem-rss:720kB, UID:10076 pgtables:1156kB oom_score_adj:-700
Test: [ 309.888679] Out of memory: Killed process 1745 (droid.bluetooth) total-vm:13720424kB, anon-rss:11084kB, file-rss:0kB, shmem-rss:208kB, UID:1002 pgtables:1220kB oom_score_adj:-700
Test: [ 311.050133] Out of memory: Killed process 1759 (ndroid.systemui) total-vm:13852268kB, anon-rss:26468kB, file-rss:0kB, shmem-rss:6988kB, UID:10075 pgtables:1628kB oom_score_adj:-800
Test: [ 313.520057] Out of memory: Killed process 2000 (m.android.phone) total-vm:13593404kB, anon-rss:14600kB, file-rss:236kB, shmem-rss:340kB, UID:1001 pgtables:1312kB oom_score_adj:-800
Test: [ 314.337744] Out of memory: Killed process 1911 (rkstack.process) total-vm:13540420kB, anon-rss:8232kB, file-rss:0kB, shmem-rss:180kB, UID:1073 pgtables:1128kB oom_score_adj:-800
Test: [ 314.745542] Out of memory: Killed process 1984 (com.android.se) total-vm:13525236kB, anon-rss:6944kB, file-rss:0kB, shmem-rss:188kB, UID:1068 pgtables:1012kB oom_score_adj:-800
Test: [ 315.007212] Out of memory: Killed process 677 (system_server) total-vm:15049836kB, anon-rss:1856kB, file-rss:0kB, shmem-rss:240kB, UID:1000 pgtables:2084kB oom_score_adj:-900
Change-Id: I78821bcd332af7b3f642f037faa2df15a937dc26
Signed-off-by: Bart Van Assche <bvanassche@google.com>
Retrieve cgroup attribute paths from task_profiles.json instead of
hardcoding these paths.
Bug: 213617178
Test: Tested lmkd in Cuttlefish.
Change-Id: I03f40ac8ccd4635f21432214e1acf997c505d1e9
Signed-off-by: Bart Van Assche <bvanassche@google.com>
Add psi memory, io and cpu 10sec averages into killinfo reports.
Bug: 205182133
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Martin Liu <liumartin@google.com>
Change-Id: Ifbcf47cab291fb20dbf0b5d32f1965f4e6462b49
Merged-In: Ifbcf47cab291fb20dbf0b5d32f1965f4e6462b49
Prevent that the statement that writes '\0' past the read data can write
past the end of the buffer.
Bug: 213617178
Test: Compile-tested only.
Change-Id: I6922c343a6bcb52dce0b5cf54f09b2850e9dfde2
Signed-off-by: Bart Van Assche <bvanassche@google.com>
Using ARRAY_SIZE() on a pointer yields 1 while applying .size() to a
pointer triggers a compiler error. Hence use .size() instead of
ARRAY_SIZE().
Bug: 213617178
Test: Compile-tested only.
Change-Id: Ie0f9740f59470c943f8d62b9475f7f987ed8707b
Signed-off-by: Bart Van Assche <bvanassche@google.com>
std::min() and std::max() check whether the argument types match but
min() and max() not. Hence switch to std::min() and std::max().
Bug: 213617178
Test: Compile-tested only.
Change-Id: Iaf1f63360c9360938db56d485dbd1e504129c52d
Signed-off-by: Bart Van Assche <bvanassche@google.com>
When system is under heavy memory pressure the system might be able
to keep free memory above the min watermark avoiding perceptible app
kills. In such situation system might end up using all its cpu
capacity on memory reclaim and not doing productive work. To detect
this condition, check memory full stall and compare it with the new
ro.lmk.stall_limit_critical tunable representing the stall threshold.
When the recorded level is over ro.lmk.stall_limit_critical, lmkd will
be allowed to kill perceptible apps. ro.lmk.stall_limit_critical
represents the max memory full stall in % that is allowed before
perceptible apps will get killed. By default it is set to 100%, which
effectively disables the feature.
Currently system stall is measured based on psi memory stall 10s average
value, however this definition might change in the future if better
metrics are developed. Setting ro.lmk.stall_limit_critical to 5 means
the system should be fully stalled (no productive work is done) for 5%
of the 10sec period, resulting in 0.5 sec loss due to the stall.
Bug: 205182133
Test: verify on heavy memory pressure test
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Martin Liu <liumartin@google.com>
Change-Id: I9713e30d82641d86d1b7edb5e1ba2971b935c898
Merged-In: I9713e30d82641d86d1b7edb5e1ba2971b935c898
Suren Baghdasaryan
Bart Van Assche
Presubmit Automerger Backend