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Hi Balbir, Do you know why in the sched_info_arrive() and sched_info_depart() functions the calculation of delta_jiffies does not use the time_after or time_before macro to prevent the miscalculation when jiffies overflow? For instance the delta_jiffies variable is simply calculated as: delta_jiffies = now - t->sched_info.last_queued; Do not you think the more logical way should be if (time_after(now, t->sched_info.last_queued)) delta_jiffies = now - t->sched_info.last_queued; else delta_jiffies = (MAX_JIFFIES - t->sched_info.last_queued) + now I have included more variables to measure some issues of schedule in the kernel (following schedstat idea) and I noticed that jiffies wraparound has led to wrong values, since the user space tool when collecting the values is producing negative values. Any comments? Can I provide a patch for that? BR, Mauricio Lin. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ | ||||||||||||
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