d0464b0c01
In some rare cases, race happens between 2 processes in the same uid. 1. Process A is dying 2. system_server calls RemoveProcessGroup() for A 3. Zygote forks Process B with the same uid of A 4. system_server calls MkdirAndChown(uid) for B 5. system_server calls MkdirAndChown(uid, pid) for B As 2 & 4/5 belong to different threads, 2 might happens before or after step 4/5, or even in the middle of 4/5. In such a case, 4 or 5 will fail, leaving process B in wrong (Zygote) group. The uid dir is only created when the corresponding apps have been launched at least once. It's reasonable to assume one of them is going to be launched again. Deleting and recreating the uid dir just slows down applaunch. Introducing a new lock in libprocessgroup can also solve the race issue. But that will slow down the applaunch further. Therefore, reusing the uid dir is an optimized way to solve the race. Ignore-AOSP-First: Freezer is not a public feature yet Bug: 192512069 Bug: 168907513 Test: Kill corresponding apps and check the uid cgroupfs dir Merged-In: I2e91088f21f45e4eda6c709a4af65ace7e135801 Change-Id: I2e91088f21f45e4eda6c709a4af65ace7e135801 |
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| .. | ||
| cgrouprc | ||
| cgrouprc_format | ||
| include/processgroup | ||
| profiles | ||
| setup | ||
| Android.bp | ||
| cgroup_map.cpp | ||
| cgroup_map.h | ||
| OWNERS | ||
| processgroup.cpp | ||
| sched_policy.cpp | ||
| task_profiles.cpp | ||
| task_profiles.h | ||