On 2015/06/25 11:00AM, Cong Wang wrote: > On Thu, May 28, 2015 at 2:11 AM, Balbir Singh <bsinghar...@gmail.com> wrote: > > On Mon, May 25, 2015 at 12:42 PM, Naveen N. Rao > > <naveen.n....@linux.vnet.ibm.com> wrote: > >> /proc/<pid>/schedstat is currently only available if CONFIG_SCHEDSTATS is > >> enabled. But, all the fields that this exposes are available and valid > >> if CONFIG_TASK_DELAY_ACCT is enabled as well. > >> > > [...] > > > The change looks reasonable, from what I can understand you want these > > changes so that you can use /proc/<pid>/schedstat instead of the > > netlink interface when CONFIG_TASK_DELAY_ACCT is enabled. > > > > Why? > > If you need the procfs interface, just enable CONFIG_SCHEDSTATS. > If you need the netlink interface, enable CONFIG_TASK_DELAY_ACCT. > They are just two different interfaces for getting the same sched > information, so why make this change? > > There must be some reason you don't want to enable > CONFIG_SCHEDSTATS? If so, please add it in the changelog. > > My guess is it depends on DEBUG_KERNEL which is not what you > want? But I see no reason it should have that dependency, it just > exposes some stats, looks like can be just removed (and moved out > of Kconfig,debug of course).
The primary issue with CONFIG_SCHEDSTATS is the (slight) additional overhead it introduces, per Kconfig. Due to this, it is not enabled by default by some of the distro kernels. Regards, Naveen -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
