Re: [PATCH v2, RESEND] sched/rt: Try to restart rt period timer when rt runtime exceeded

On Fri, Dec 03, 2021 at 03:36:18AM +0000, Li Hua wrote:

When rt_runtime is modified from -1 to a valid control value, it may cause the task to be throttled all the time. Operations like the following will trigger the bug. E.g:

1. echo -1 > /proc/sys/kernel/sched_rt_runtime_us
2. Run a FIFO task named A that executes while(1)
3. echo 950000 > /proc/sys/kernel/sched_rt_runtime_us

When rt_runtime is -1, The rt period timer will not be activated when task A enqueued. And then the task will be throttled after setting rt_runtime to 950,000. The task will always be throttled because the rt period timer is not activated.

Reported-by: Hulk Robot hulkci@huawei.com Signed-off-by: Li Hua hucool.lihua@huawei.com

Thanks, do you think you can reply here with a Fixes: tag so I can add it?