[patch 1/3] nohz: only wakeup a single target cpu when kicking a task

2021-01-28 Thread Marcelo Tosatti
When adding a tick dependency to a task, its necessary to wakeup the CPU where the task resides to reevaluate tick dependencies on that CPU. However the current code wakes up all nohz_full CPUs, which is unnecessary. Switch to waking up a single CPU, by using ordering of writes to task->cpu and

[patch 1/3] nohz: only wakeup a single target cpu when kicking a task

2021-01-28 Thread Marcelo Tosatti
When adding a tick dependency to a task, its necessary to wakeup the CPU where the task resides to reevaluate tick dependencies on that CPU. However the current code wakes up all nohz_full CPUs, which is unnecessary. Switch to waking up a single CPU, by using ordering of writes to task->cpu and