Re: [PATCH v5 13/19] sched: Split out __sched() deactivate task logic into a helper
From: kernel test robot
Date: Wed Aug 23 2023 - 20:05:04 EST
Hi John,
kernel test robot noticed the following build warnings:
[auto build test WARNING on tip/locking/core]
[also build test WARNING on linus/master tip/auto-latest v6.5-rc7]
[cannot apply to tip/sched/core tip/master next-20230823]
[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/John-Stultz/sched-Unify-runtime-accounting-across-classes/20230821-121604
base: tip/locking/core
patch link: https://lore.kernel.org/r/20230819060915.3001568-14-jstultz%40google.com
patch subject: [PATCH v5 13/19] sched: Split out __sched() deactivate task logic into a helper
config: um-allnoconfig (https://download.01.org/0day-ci/archive/20230824/202308240712.RzqTiO81-lkp@xxxxxxxxx/config)
compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project.git 4a5ac14ee968ff0ad5d2cc1ffa0299048db4c88a)
reproduce: (https://download.01.org/0day-ci/archive/20230824/202308240712.RzqTiO81-lkp@xxxxxxxxx/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@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202308240712.RzqTiO81-lkp@xxxxxxxxx/
All warnings (new ones prefixed by >>):
In file included from kernel/sched/core.c:9:
In file included from include/linux/highmem.h:12:
In file included from include/linux/hardirq.h:11:
In file included from arch/um/include/asm/hardirq.h:5:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/um/include/asm/io.h:24:
include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
547 | val = __raw_readb(PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
560 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu'
37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
| ^
In file included from kernel/sched/core.c:9:
In file included from include/linux/highmem.h:12:
In file included from include/linux/hardirq.h:11:
In file included from arch/um/include/asm/hardirq.h:5:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/um/include/asm/io.h:24:
include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
573 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr));
| ~~~~~~~~~~ ^
include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu'
35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
| ^
In file included from kernel/sched/core.c:9:
In file included from include/linux/highmem.h:12:
In file included from include/linux/hardirq.h:11:
In file included from arch/um/include/asm/hardirq.h:5:
In file included from include/asm-generic/hardirq.h:17:
In file included from include/linux/irq.h:20:
In file included from include/linux/io.h:13:
In file included from arch/um/include/asm/io.h:24:
include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
584 | __raw_writeb(value, PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
594 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
604 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:692:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
692 | readsb(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:700:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
700 | readsw(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:708:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
708 | readsl(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:717:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
717 | writesb(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:726:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
726 | writesw(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
include/asm-generic/io.h:735:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
735 | writesl(PCI_IOBASE + addr, buffer, count);
| ~~~~~~~~~~ ^
>> kernel/sched/core.c:6565:6: warning: no previous prototype for function 'try_to_deactivate_task' [-Wmissing-prototypes]
6565 | bool try_to_deactivate_task(struct rq *rq, struct task_struct *p, unsigned long state)
| ^
kernel/sched/core.c:6565:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
6565 | bool try_to_deactivate_task(struct rq *rq, struct task_struct *p, unsigned long state)
| ^
| static
kernel/sched/core.c:3697:20: warning: unused function 'rq_has_pinned_tasks' [-Wunused-function]
3697 | static inline bool rq_has_pinned_tasks(struct rq *rq)
| ^
kernel/sched/core.c:5834:20: warning: unused function 'sched_tick_start' [-Wunused-function]
5834 | static inline void sched_tick_start(int cpu) { }
| ^
kernel/sched/core.c:5835:20: warning: unused function 'sched_tick_stop' [-Wunused-function]
5835 | static inline void sched_tick_stop(int cpu) { }
| ^
kernel/sched/core.c:6535:20: warning: unused function 'sched_core_cpu_starting' [-Wunused-function]
6535 | static inline void sched_core_cpu_starting(unsigned int cpu) {}
| ^
kernel/sched/core.c:6536:20: warning: unused function 'sched_core_cpu_deactivate' [-Wunused-function]
6536 | static inline void sched_core_cpu_deactivate(unsigned int cpu) {}
| ^
kernel/sched/core.c:6537:20: warning: unused function 'sched_core_cpu_dying' [-Wunused-function]
6537 | static inline void sched_core_cpu_dying(unsigned int cpu) {}
| ^
19 warnings generated.
vim +/try_to_deactivate_task +6565 kernel/sched/core.c
6564
> 6565 bool try_to_deactivate_task(struct rq *rq, struct task_struct *p, unsigned long state)
6566 {
6567 if (signal_pending_state(state, p)) {
6568 WRITE_ONCE(p->__state, TASK_RUNNING);
6569 } else {
6570 p->sched_contributes_to_load =
6571 (state & TASK_UNINTERRUPTIBLE) &&
6572 !(state & TASK_NOLOAD) &&
6573 !(state & TASK_FROZEN);
6574
6575 if (p->sched_contributes_to_load)
6576 rq->nr_uninterruptible++;
6577
6578 /*
6579 * __schedule() ttwu()
6580 * prev_state = prev->state; if (p->on_rq && ...)
6581 * if (prev_state) goto out;
6582 * p->on_rq = 0; smp_acquire__after_ctrl_dep();
6583 * p->state = TASK_WAKING
6584 *
6585 * Where __schedule() and ttwu() have matching control dependencies.
6586 *
6587 * After this, schedule() must not care about p->state any more.
6588 */
6589 deactivate_task(rq, p, DEQUEUE_SLEEP | DEQUEUE_NOCLOCK);
6590
6591 if (p->in_iowait) {
6592 atomic_inc(&rq->nr_iowait);
6593 delayacct_blkio_start();
6594 }
6595 return true;
6596 }
6597 return false;
6598 }
6599
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki