On 2019/06/20 14:55, Yafang Shao wrote: > When sys_hung_task_warnings reaches 0, the hang task messages will not > be reported any more.
It is a common mistake that sys_hung_task_warnings is already 0 when a real problem which should be reported occurred. > > If the user want to get more hung task messages, he must reset > kernel.hung_task_warnings to a postive integer or -1 with sysctl. People are setting sys_hung_task_warnings to -1 in order to make sure that the messages are printed. > This is not a good way for the user. But I don't think we should reset automatically. > We'd better reset hung task warnings in the kernel, and then the user > don't need to pay attention to this value. I suggest changing the default value of sys_hung_task_warnings to -1. > > With this patch, hung task warnings will be reset with > sys_hung_task_warnings setting in evenry check interval. Since it is uncommon that the messages are printed for more than 10 times for one check_hung_uninterruptible_tasks() call, this patch is effectively changing to always print the messages (in other words, setting -1).
