[linux-rt-devel:linux-5.14.y-rt-rebase 245/263] kernel/sched/core.c:6336:19: warning: unused function 'preemptible_lazy'

From: kernel test robot
Date: Thu Sep 09 2021 - 06:58:33 EST


tree: https://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-5.14.y-rt-rebase
head: a1ea175d809fdb71148c7f6ff7f3f59b9b47b257
commit: 7ac22c0eae125aba94455aae5ac98daf623d4174 [245/263] sched: Add support for lazy preemption
config: mips-randconfig-r004-20210908 (attached as .config)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 261cbe98c38f8c1ee1a482fe76511110e790f58a)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install mips cross compiling tool for clang build
# apt-get install binutils-mips-linux-gnu
# https://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git/commit/?id=7ac22c0eae125aba94455aae5ac98daf623d4174
git remote add linux-rt-devel https://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git
git fetch --no-tags linux-rt-devel linux-5.14.y-rt-rebase
git checkout 7ac22c0eae125aba94455aae5ac98daf623d4174
# save the attached .config to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross O=build_dir ARCH=mips SHELL=/bin/bash kernel/sched/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

kernel/sched/core.c:3320:20: warning: unused function 'rq_has_pinned_tasks'
static inline bool rq_has_pinned_tasks(struct rq
^
kernel/sched/core.c:5214:20: warning: unused function 'sched_tick_start'
static inline void sched_tick_start(int cpu) { }
^
kernel/sched/core.c:5215:20: warning: unused function 'sched_tick_stop'
static inline void sched_tick_stop(int cpu) { }
^
kernel/sched/core.c:5944:20: warning: unused function 'sched_core_cpu_starting'
static inline void sched_core_cpu_starting(unsigned int cpu) {}
^
kernel/sched/core.c:5945:20: warning: unused function 'sched_core_cpu_deactivate'
static inline void sched_core_cpu_deactivate(unsigned int cpu) {}
^
kernel/sched/core.c:5946:20: warning: unused function 'sched_core_cpu_dying'
static inline void sched_core_cpu_dying(unsigned int cpu) {}
^
>> kernel/sched/core.c:6336:19: warning: unused function 'preemptible_lazy'
static inline int preemptible_lazy(void)
^
fatal error: error in backend: Nested variants found in inline asm string: ' .set push
.set noat
.set push
.set arch=r4000
.if ( 0x00 ) != -1)) 0x00 ) != -1)) : ($( static struct ftrace_branch_data __attribute__((__aligned__(4))) __attribute__((__section__("_ftrace_branch"))) __if_trace = $( .func = __func__, .file = "arch/mips/include/asm/cmpxchg.h", .line = 163, $); 0x00 ) != -1)) : $))) ) && ( 0 ); .set push; .set mips64r2; .rept 1; sync 0x00; .endr; .set pop; .else; ; .endif
1: ll $0, $2 # __cmpxchg_asm
bne $0, ${3:z}, 2f
.set pop
move $$1, ${4:z}
.set arch=r4000
sc $$1, $1
beqz $$1, 1b
.set pop
2: .if ( 0x00 ) != -1)) 0x00 ) != -1)) : ($( static struct ftrace_branch_data __attribute__((__aligned__(4))) __attribute__((__section__("_ftrace_branch"))) __if_trace = $( .func = __func__, .file = "arch/mips/include/asm/cmpxchg.h", .line = 163, $); 0x00 ) != -1)) : $))) ) && ( 0 ); .set push; .set mips64r2; .rept 1; sync 0x00; .endr; .set pop; .else; ; .endif
'
clang-14: error: clang frontend command failed with exit code 70 (use -v to see invocation)
clang version 14.0.0 (git://gitmirror/llvm_project 261cbe98c38f8c1ee1a482fe76511110e790f58a)
Target: mipsel-unknown-linux
Thread model: posix
InstalledDir: /opt/cross/clang-261cbe98c3/bin
clang-14: note: diagnostic msg:
Makefile arch include kernel nr_bisected scripts source usr


vim +/preemptible_lazy +6336 kernel/sched/core.c

6335
> 6336 static inline int preemptible_lazy(void)
6337 {
6338 return 1;
6339 }
6340

---
0-DAY CI Kernel Test Service, Intel Corporation
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Attachment: .config.gz
Description: application/gzip