Ingo Molnar wrote: > * Balbir Singh <[EMAIL PROTECTED]> wrote: > >> Fix the delay accounting regression introduced by commit >> 75d4ef16a6aa84f708188bada182315f80aab6fa. rq no longer has sched_info >> data associated with it. task_struct sched_info structure is used by >> delay accounting to provide back statistics to user space. > > no, this really is broken code. sched_clock() is not a generally > reliable time source so at a minimum the rq->clock fix i mentioned is > needed. What user-space tools are utilizing delay-accounting by the way?
Applications I can think of are 1. iotop 2. Some typical applications are mentioned in https://ols2006.108.redhat.com/2007/Reprints/nagar-Reprint.pdf > We have most of this data available under SCHEDSTATS - how about > consolidating CONFIG_TASK_DELAY_ACCT into CONFIG_SCHEDSTATS? > > Ingo Yes, we do use schedstats - except for two cases that I know of? 1. To accumulate information in taskstats to share with user space (we copy the data from schedstats into taskstats) 2. We accumulate the data for dead threads in a thread group -- Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
