kernel/sched/core.c | 2 ++ 1 file changed, 2 insertions(+)
When build with CONFIG_UCLAMP_TASK && !CONFIG_UCLAMP_TASK_GROUP,
the variable 'uclamp_mutex' is defined but not used:
kernel/sched/core.c:1361:21: warning: 'uclamp_mutex' defined but not used [-Wunused-variable]
1361 | static DEFINE_MUTEX(uclamp_mutex);
Fix this by only defining the variable uclamp_mutex when the
CONFIG_UCLAMP_TASK_GROUP is enabled.
Fixes: 2480c093130f ("sched/uclamp: Extend CPU's cgroup controller")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/lkml/202410250459.EJe6PJI5-lkp@intel.com/
Signed-off-by: Qi Xi <xiqi2@huawei.com>
---
kernel/sched/core.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index f3951e4a55e5..9109fed6f022 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -1348,6 +1348,7 @@ void set_load_weight(struct task_struct *p, bool update_load)
}
#ifdef CONFIG_UCLAMP_TASK
+#ifdef CONFIG_UCLAMP_TASK_GROUP
/*
* Serializes updates of utilization clamp values
*
@@ -1359,6 +1360,7 @@ void set_load_weight(struct task_struct *p, bool update_load)
* updates or API abuses.
*/
static DEFINE_MUTEX(uclamp_mutex);
+#endif /* CONFIG_UCLAMP_TASK_GROUP */
/* Max allowed minimum utilization */
static unsigned int __maybe_unused sysctl_sched_uclamp_util_min = SCHED_CAPACITY_SCALE;
--
2.33.0Hi Qi,
kernel test robot noticed the following build errors:
[auto build test ERROR on tip/sched/core]
[also build test ERROR on linus/master v6.12-rc4 next-20241025]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Qi-Xi/sched-Fix-compile-warning-about-variable-uclamp_mutex/20241025-115315
base: tip/sched/core
patch link: https://lore.kernel.org/r/20241025034740.546570-1-xiqi2%40huawei.com
patch subject: [PATCH] sched: Fix compile warning about variable 'uclamp_mutex'
config: i386-randconfig-053-20241026 (https://download.01.org/0day-ci/archive/20241026/202410260638.VpY4j0AB-lkp@intel.com/config)
compiler: clang version 19.1.2 (https://github.com/llvm/llvm-project 7ba7d8e2f7b6445b60679da826210cdde29eaf8b)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241026/202410260638.VpY4j0AB-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202410260638.VpY4j0AB-lkp@intel.com/
All errors (new ones prefixed by >>):
In file included from kernel/sched/core.c:10:
In file included from include/linux/highmem.h:8:
In file included from include/linux/cacheflush.h:5:
In file included from arch/x86/include/asm/cacheflush.h:5:
In file included from include/linux/mm.h:2213:
include/linux/vmstat.h:518:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
518 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
| ~~~~~~~~~~~ ^ ~~~
>> kernel/sched/core.c:1865:16: error: use of undeclared identifier 'uclamp_mutex'; did you mean 'uclamp_none'?
1865 | guard(mutex)(&uclamp_mutex);
| ^~~~~~~~~~~~
| uclamp_none
kernel/sched/sched.h:3377:28: note: 'uclamp_none' declared here
3377 | static inline unsigned int uclamp_none(enum uclamp_id clamp_id)
| ^
1 warning and 1 error generated.
vim +1865 kernel/sched/core.c
494dcdf46e5cde YueHaibing 2022-04-27 1857
78eb4ea25cd5fd Joel Granados 2024-07-24 1858 static int sysctl_sched_uclamp_handler(const struct ctl_table *table, int write,
32927393dc1ccd Christoph Hellwig 2020-04-24 1859 void *buffer, size_t *lenp, loff_t *ppos)
e8f14172c6b11e Patrick Bellasi 2019-06-21 1860 {
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1861 bool update_root_tg = false;
13685c4a08fca9 Qais Yousef 2020-07-16 1862 int old_min, old_max, old_min_rt;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1863 int result;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1864
0f92cdf36f848f Peter Zijlstra 2023-08-01 @1865 guard(mutex)(&uclamp_mutex);
0f92cdf36f848f Peter Zijlstra 2023-08-01 1866
e8f14172c6b11e Patrick Bellasi 2019-06-21 1867 old_min = sysctl_sched_uclamp_util_min;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1868 old_max = sysctl_sched_uclamp_util_max;
13685c4a08fca9 Qais Yousef 2020-07-16 1869 old_min_rt = sysctl_sched_uclamp_util_min_rt_default;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1870
e8f14172c6b11e Patrick Bellasi 2019-06-21 1871 result = proc_dointvec(table, write, buffer, lenp, ppos);
e8f14172c6b11e Patrick Bellasi 2019-06-21 1872 if (result)
e8f14172c6b11e Patrick Bellasi 2019-06-21 1873 goto undo;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1874 if (!write)
0f92cdf36f848f Peter Zijlstra 2023-08-01 1875 return 0;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1876
e8f14172c6b11e Patrick Bellasi 2019-06-21 1877 if (sysctl_sched_uclamp_util_min > sysctl_sched_uclamp_util_max ||
13685c4a08fca9 Qais Yousef 2020-07-16 1878 sysctl_sched_uclamp_util_max > SCHED_CAPACITY_SCALE ||
13685c4a08fca9 Qais Yousef 2020-07-16 1879 sysctl_sched_uclamp_util_min_rt_default > SCHED_CAPACITY_SCALE) {
13685c4a08fca9 Qais Yousef 2020-07-16 1880
e8f14172c6b11e Patrick Bellasi 2019-06-21 1881 result = -EINVAL;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1882 goto undo;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1883 }
e8f14172c6b11e Patrick Bellasi 2019-06-21 1884
e8f14172c6b11e Patrick Bellasi 2019-06-21 1885 if (old_min != sysctl_sched_uclamp_util_min) {
e8f14172c6b11e Patrick Bellasi 2019-06-21 1886 uclamp_se_set(&uclamp_default[UCLAMP_MIN],
a509a7cd797470 Patrick Bellasi 2019-06-21 1887 sysctl_sched_uclamp_util_min, false);
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1888 update_root_tg = true;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1889 }
e8f14172c6b11e Patrick Bellasi 2019-06-21 1890 if (old_max != sysctl_sched_uclamp_util_max) {
e8f14172c6b11e Patrick Bellasi 2019-06-21 1891 uclamp_se_set(&uclamp_default[UCLAMP_MAX],
a509a7cd797470 Patrick Bellasi 2019-06-21 1892 sysctl_sched_uclamp_util_max, false);
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1893 update_root_tg = true;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1894 }
e8f14172c6b11e Patrick Bellasi 2019-06-21 1895
46609ce227039f Qais Yousef 2020-06-30 1896 if (update_root_tg) {
46609ce227039f Qais Yousef 2020-06-30 1897 static_branch_enable(&sched_uclamp_used);
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1898 uclamp_update_root_tg();
46609ce227039f Qais Yousef 2020-06-30 1899 }
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1900
13685c4a08fca9 Qais Yousef 2020-07-16 1901 if (old_min_rt != sysctl_sched_uclamp_util_min_rt_default) {
13685c4a08fca9 Qais Yousef 2020-07-16 1902 static_branch_enable(&sched_uclamp_used);
13685c4a08fca9 Qais Yousef 2020-07-16 1903 uclamp_sync_util_min_rt_default();
13685c4a08fca9 Qais Yousef 2020-07-16 1904 }
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1905
e8f14172c6b11e Patrick Bellasi 2019-06-21 1906 /*
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1907 * We update all RUNNABLE tasks only when task groups are in use.
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1908 * Otherwise, keep it simple and do just a lazy update at each next
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1909 * task enqueue time.
e8f14172c6b11e Patrick Bellasi 2019-06-21 1910 */
0f92cdf36f848f Peter Zijlstra 2023-08-01 1911 return 0;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1912
e8f14172c6b11e Patrick Bellasi 2019-06-21 1913 undo:
e8f14172c6b11e Patrick Bellasi 2019-06-21 1914 sysctl_sched_uclamp_util_min = old_min;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1915 sysctl_sched_uclamp_util_max = old_max;
13685c4a08fca9 Qais Yousef 2020-07-16 1916 sysctl_sched_uclamp_util_min_rt_default = old_min_rt;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1917 return result;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1918 }
494dcdf46e5cde YueHaibing 2022-04-27 1919 #endif
e8f14172c6b11e Patrick Bellasi 2019-06-21 1920
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
Hi Qi,
kernel test robot noticed the following build errors:
[auto build test ERROR on tip/sched/core]
[also build test ERROR on linus/master v6.12-rc4 next-20241025]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Qi-Xi/sched-Fix-compile-warning-about-variable-uclamp_mutex/20241025-115315
base: tip/sched/core
patch link: https://lore.kernel.org/r/20241025034740.546570-1-xiqi2%40huawei.com
patch subject: [PATCH] sched: Fix compile warning about variable 'uclamp_mutex'
config: i386-randconfig-052-20241026 (https://download.01.org/0day-ci/archive/20241026/202410260511.Ky8AtElD-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241026/202410260511.Ky8AtElD-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202410260511.Ky8AtElD-lkp@intel.com/
All errors (new ones prefixed by >>):
kernel/sched/core.c: In function 'sysctl_sched_uclamp_handler':
>> kernel/sched/core.c:1865:23: error: 'uclamp_mutex' undeclared (first use in this function); did you mean 'uclamp_none'?
1865 | guard(mutex)(&uclamp_mutex);
| ^~~~~~~~~~~~
| uclamp_none
kernel/sched/core.c:1865:23: note: each undeclared identifier is reported only once for each function it appears in
vim +1865 kernel/sched/core.c
494dcdf46e5cde YueHaibing 2022-04-27 1857
78eb4ea25cd5fd Joel Granados 2024-07-24 1858 static int sysctl_sched_uclamp_handler(const struct ctl_table *table, int write,
32927393dc1ccd Christoph Hellwig 2020-04-24 1859 void *buffer, size_t *lenp, loff_t *ppos)
e8f14172c6b11e Patrick Bellasi 2019-06-21 1860 {
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1861 bool update_root_tg = false;
13685c4a08fca9 Qais Yousef 2020-07-16 1862 int old_min, old_max, old_min_rt;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1863 int result;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1864
0f92cdf36f848f Peter Zijlstra 2023-08-01 @1865 guard(mutex)(&uclamp_mutex);
0f92cdf36f848f Peter Zijlstra 2023-08-01 1866
e8f14172c6b11e Patrick Bellasi 2019-06-21 1867 old_min = sysctl_sched_uclamp_util_min;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1868 old_max = sysctl_sched_uclamp_util_max;
13685c4a08fca9 Qais Yousef 2020-07-16 1869 old_min_rt = sysctl_sched_uclamp_util_min_rt_default;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1870
e8f14172c6b11e Patrick Bellasi 2019-06-21 1871 result = proc_dointvec(table, write, buffer, lenp, ppos);
e8f14172c6b11e Patrick Bellasi 2019-06-21 1872 if (result)
e8f14172c6b11e Patrick Bellasi 2019-06-21 1873 goto undo;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1874 if (!write)
0f92cdf36f848f Peter Zijlstra 2023-08-01 1875 return 0;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1876
e8f14172c6b11e Patrick Bellasi 2019-06-21 1877 if (sysctl_sched_uclamp_util_min > sysctl_sched_uclamp_util_max ||
13685c4a08fca9 Qais Yousef 2020-07-16 1878 sysctl_sched_uclamp_util_max > SCHED_CAPACITY_SCALE ||
13685c4a08fca9 Qais Yousef 2020-07-16 1879 sysctl_sched_uclamp_util_min_rt_default > SCHED_CAPACITY_SCALE) {
13685c4a08fca9 Qais Yousef 2020-07-16 1880
e8f14172c6b11e Patrick Bellasi 2019-06-21 1881 result = -EINVAL;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1882 goto undo;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1883 }
e8f14172c6b11e Patrick Bellasi 2019-06-21 1884
e8f14172c6b11e Patrick Bellasi 2019-06-21 1885 if (old_min != sysctl_sched_uclamp_util_min) {
e8f14172c6b11e Patrick Bellasi 2019-06-21 1886 uclamp_se_set(&uclamp_default[UCLAMP_MIN],
a509a7cd797470 Patrick Bellasi 2019-06-21 1887 sysctl_sched_uclamp_util_min, false);
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1888 update_root_tg = true;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1889 }
e8f14172c6b11e Patrick Bellasi 2019-06-21 1890 if (old_max != sysctl_sched_uclamp_util_max) {
e8f14172c6b11e Patrick Bellasi 2019-06-21 1891 uclamp_se_set(&uclamp_default[UCLAMP_MAX],
a509a7cd797470 Patrick Bellasi 2019-06-21 1892 sysctl_sched_uclamp_util_max, false);
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1893 update_root_tg = true;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1894 }
e8f14172c6b11e Patrick Bellasi 2019-06-21 1895
46609ce227039f Qais Yousef 2020-06-30 1896 if (update_root_tg) {
46609ce227039f Qais Yousef 2020-06-30 1897 static_branch_enable(&sched_uclamp_used);
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1898 uclamp_update_root_tg();
46609ce227039f Qais Yousef 2020-06-30 1899 }
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1900
13685c4a08fca9 Qais Yousef 2020-07-16 1901 if (old_min_rt != sysctl_sched_uclamp_util_min_rt_default) {
13685c4a08fca9 Qais Yousef 2020-07-16 1902 static_branch_enable(&sched_uclamp_used);
13685c4a08fca9 Qais Yousef 2020-07-16 1903 uclamp_sync_util_min_rt_default();
13685c4a08fca9 Qais Yousef 2020-07-16 1904 }
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1905
e8f14172c6b11e Patrick Bellasi 2019-06-21 1906 /*
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1907 * We update all RUNNABLE tasks only when task groups are in use.
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1908 * Otherwise, keep it simple and do just a lazy update at each next
7274a5c1bbec45 Patrick Bellasi 2019-08-22 1909 * task enqueue time.
e8f14172c6b11e Patrick Bellasi 2019-06-21 1910 */
0f92cdf36f848f Peter Zijlstra 2023-08-01 1911 return 0;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1912
e8f14172c6b11e Patrick Bellasi 2019-06-21 1913 undo:
e8f14172c6b11e Patrick Bellasi 2019-06-21 1914 sysctl_sched_uclamp_util_min = old_min;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1915 sysctl_sched_uclamp_util_max = old_max;
13685c4a08fca9 Qais Yousef 2020-07-16 1916 sysctl_sched_uclamp_util_min_rt_default = old_min_rt;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1917 return result;
e8f14172c6b11e Patrick Bellasi 2019-06-21 1918 }
494dcdf46e5cde YueHaibing 2022-04-27 1919 #endif
e8f14172c6b11e Patrick Bellasi 2019-06-21 1920
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
On Fri, Oct 25, 2024 at 11:47:40AM +0800, Qi Xi wrote: > When build with CONFIG_UCLAMP_TASK && !CONFIG_UCLAMP_TASK_GROUP, > the variable 'uclamp_mutex' is defined but not used: > > kernel/sched/core.c:1361:21: warning: 'uclamp_mutex' defined but not used [-Wunused-variable] > 1361 | static DEFINE_MUTEX(uclamp_mutex); > > Fix this by only defining the variable uclamp_mutex when the > CONFIG_UCLAMP_TASK_GROUP is enabled. sigh.. I hate our CONFIG space :/ Perhaps add __maybe_unused like the other variables it sits right next to instead of adding yet more #ifdef crud?
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