kernel/sched/rt.c:9:18: warning: 'max_rt_runtime' defined but not used

kernel/sched/rt.c:9:18: warning: 'max_rt_runtime' defined but not used

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   7e284070abe53d448517b80493863595af4ab5f0
commit: 28f152cd0926596e69d412467b11b6fe6fe4e864 sched/rt: fix build error when CONFIG_SYSCTL is disable
date:   7 weeks ago
config: i386-tinyconfig (https://download.01.org/0day-ci/archive/20220528/202205280150.1w6rdhr4-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.3.0-1) 11.3.0
reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=28f152cd0926596e69d412467b11b6fe6fe4e864
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout 28f152cd0926596e69d412467b11b6fe6fe4e864
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash kernel/

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   In file included from kernel/sched/build_policy.c:43:
   kernel/sched/rt.c:309:6: warning: no previous prototype for 'unregister_rt_sched_group' [-Wmissing-prototypes]
     309 | void unregister_rt_sched_group(struct task_group *tg) { }
         |      ^~~~~~~~~~~~~~~~~~~~~~~~~
   kernel/sched/rt.c:311:6: warning: no previous prototype for 'free_rt_sched_group' [-Wmissing-prototypes]
     311 | void free_rt_sched_group(struct task_group *tg) { }
         |      ^~~~~~~~~~~~~~~~~~~
   kernel/sched/rt.c:313:5: warning: no previous prototype for 'alloc_rt_sched_group' [-Wmissing-prototypes]
     313 | int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
         |     ^~~~~~~~~~~~~~~~~~~~
   kernel/sched/rt.c:716:6: warning: no previous prototype for 'sched_rt_bandwidth_account' [-Wmissing-prototypes]
     716 | bool sched_rt_bandwidth_account(struct rt_rq *rt_rq)
         |      ^~~~~~~~~~~~~~~~~~~~~~~~~~
>> kernel/sched/rt.c:9:18: warning: 'max_rt_runtime' defined but not used [-Wunused-const-variable=]
       9 | static const u64 max_rt_runtime = MAX_BW;
         |                  ^~~~~~~~~~~~~~


vim +/max_rt_runtime +9 kernel/sched/rt.c

d505b8af58912a Huaixin Chang  2020-04-25  @9  static const u64 max_rt_runtime = MAX_BW;
ce0dbbbb30aee6 Clark Williams 2013-02-07  10  

:::::: The code at line 9 was first introduced by commit
:::::: d505b8af58912ae1e1a211fabc9995b19bd40828 sched: Defend cfs and rt bandwidth quota against overflow

:::::: TO: Huaixin Chang <changhuaixin@linux.alibaba.com>
:::::: CC: Peter Zijlstra <peterz@infradead.org>

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

[PATCH] sched/rt: fix compilation on i386 for umax_rt_runtime

[Luis Chamberlain]

On i386 you can end up with this compilation warning:

kernel/sched/rt.c:9:18: warning: 'max_rt_runtime' defined but not used [-Wunused-const-variable=]

This can happen when SYSCTL or RT_GROUP_SCHED is disabled.
Fix this.

Reported-by: kernel test robot <lkp@intel.com>
Cc: Baisong Zhong <zhongbaisong@huawei.com>
Signed-off-by: Luis Chamberlain <mcgrof@bgt140507bm04>
---
 kernel/sched/rt.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 8c9ed9664840..eb2a167be098 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -5,8 +5,10 @@
  */
 
 int sched_rr_timeslice = RR_TIMESLICE;
+#if defined(CONFIG_SYSCTL) || defined(CONFIG_RT_GROUP_SCHED)
 /* More than 4 hours if BW_SHIFT equals 20. */
 static const u64 max_rt_runtime = MAX_BW;
+#endif
 
 static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun);
 
-- 
2.35.1

[PATCH] sched/rt: fix compilation on i386 for umax_rt_runtime

[Luis Chamberlain]

[-- Attachment #1: Type: text/plain, Size: 922 bytes --]

On i386 you can end up with this compilation warning:

kernel/sched/rt.c:9:18: warning: 'max_rt_runtime' defined but not used [-Wunused-const-variable=]

This can happen when SYSCTL or RT_GROUP_SCHED is disabled.
Fix this.

Reported-by: kernel test robot <lkp@intel.com>
Cc: Baisong Zhong <zhongbaisong@huawei.com>
Signed-off-by: Luis Chamberlain <mcgrof@bgt140507bm04>
---
 kernel/sched/rt.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 8c9ed9664840..eb2a167be098 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -5,8 +5,10 @@
  */
 
 int sched_rr_timeslice = RR_TIMESLICE;
+#if defined(CONFIG_SYSCTL) || defined(CONFIG_RT_GROUP_SCHED)
 /* More than 4 hours if BW_SHIFT equals 20. */
 static const u64 max_rt_runtime = MAX_BW;
+#endif
 
 static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun);
 
-- 
2.35.1