Re: [PATCH] sched/rt: Remove unnecessary CONFIG_RT_GROUP_SCHED in rt_se_prio()

From: åçæ
Date: Tue Oct 30 2018 - 11:42:37 EST


Hi,

I am sorry that I did not consider CONFIG_SMP is also not configured.
In this case, 'struct rt_rq' has no member named 'highest_prio'. So, I
I understand why the code here needs CONFIG_RT_GROUP_SCHED.
When CONFIG_SMP or CONFIG_RT_GROUP_SCHED is configured,
'struct rt_rq' will have member named 'highest_prio'.

So, this patch does't make sense.


kbuild test robot <lkp@xxxxxxxxx> ä2018å10æ30æåä äå11:14åéï
>
> Hi Muchun,
>
> Thank you for the patch! Yet something to improve:
>
> [auto build test ERROR on tip/sched/core]
> [also build test ERROR on v4.19 next-20181030]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>
> url: https://github.com/0day-ci/linux/commits/Muchun-Song/sched-rt-Remove-unnecessary-CONFIG_RT_GROUP_SCHED-in-rt_se_prio/20181030-225925
> config: i386-randconfig-x002-201843 (attached as .config)
> compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
> reproduce:
> # save the attached .config to linux build tree
> make ARCH=i386
>
> All errors (new ones prefixed by >>):
>
> kernel/sched/rt.c: In function 'rt_se_prio':
> >> kernel/sched/rt.c:900:15: error: 'struct rt_rq' has no member named 'highest_prio'
> return rt_rq->highest_prio.curr;
> ^~
>
> vim +900 kernel/sched/rt.c
>
> ac086bc2 kernel/sched_rt.c Peter Zijlstra 2008-04-19 894
> 6f505b16 kernel/sched_rt.c Peter Zijlstra 2008-01-25 895 static inline int rt_se_prio(struct sched_rt_entity *rt_se)
> 6f505b16 kernel/sched_rt.c Peter Zijlstra 2008-01-25 896 {
> 6f505b16 kernel/sched_rt.c Peter Zijlstra 2008-01-25 897 struct rt_rq *rt_rq = group_rt_rq(rt_se);
> 6f505b16 kernel/sched_rt.c Peter Zijlstra 2008-01-25 898
> 6f505b16 kernel/sched_rt.c Peter Zijlstra 2008-01-25 899 if (rt_rq)
> e864c499 kernel/sched_rt.c Gregory Haskins 2008-12-29 @900 return rt_rq->highest_prio.curr;
> 6f505b16 kernel/sched_rt.c Peter Zijlstra 2008-01-25 901
> 6f505b16 kernel/sched_rt.c Peter Zijlstra 2008-01-25 902 return rt_task_of(rt_se)->prio;
> 6f505b16 kernel/sched_rt.c Peter Zijlstra 2008-01-25 903 }
> 6f505b16 kernel/sched_rt.c Peter Zijlstra 2008-01-25 904
>
> :::::: The code at line 900 was first introduced by commit
> :::::: e864c499d9e57805ae1f9e7ea404dd223759cd53 sched: track the next-highest priority on each runqueue
>
> :::::: TO: Gregory Haskins <ghaskins@xxxxxxxxxx>
> :::::: CC: Gregory Haskins <ghaskins@xxxxxxxxxx>
>
> ---
> 0-DAY kernel test infrastructure Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all Intel Corporation