All of lore.kernel.org
 help / color / mirror / Atom feed
From: kernel test robot <lkp@intel.com>
To: Roman Kagan <rkagan@amazon.de>, linux-kernel@vger.kernel.org
Cc: llvm@lists.linux.dev, oe-kbuild-all@lists.linux.dev,
	Daniel Bristot de Oliveira <bristot@redhat.com>,
	Ben Segall <bsegall@google.com>,
	Zhang Qiao <zhangqiao22@huawei.com>,
	Ingo Molnar <mingo@redhat.com>, Waiman Long <longman@redhat.com>,
	Dietmar Eggemann <dietmar.eggemann@arm.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Valentin Schneider <vschneid@redhat.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Mel Gorman <mgorman@suse.de>, Juri Lelli <juri.lelli@redhat.com>
Subject: Re: [PATCH] sched/fair: sanitize vruntime of entity being placed
Date: Sat, 28 Jan 2023 15:45:42 +0800	[thread overview]
Message-ID: <202301281536.CiaoBlBO-lkp@intel.com> (raw)
In-Reply-To: <20230127163230.3339408-1-rkagan@amazon.de>

Hi Roman,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on tip/sched/core]
[also build test WARNING on linus/master v6.2-rc5]
[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/Roman-Kagan/sched-fair-sanitize-vruntime-of-entity-being-placed/20230128-130846
patch link:    https://lore.kernel.org/r/20230127163230.3339408-1-rkagan%40amazon.de
patch subject: [PATCH] sched/fair: sanitize vruntime of entity being placed
config: hexagon-randconfig-r041-20230123 (https://download.01.org/0day-ci/archive/20230128/202301281536.CiaoBlBO-lkp@intel.com/config)
compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 4196ca3278f78c6e19246e54ab0ecb364e37d66a)
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
        # https://github.com/intel-lab-lkp/linux/commit/2db31a18bcb88c280481672d7721f7e003d8df5a
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Roman-Kagan/sched-fair-sanitize-vruntime-of-entity-being-placed/20230128-130846
        git checkout 2db31a18bcb88c280481672d7721f7e003d8df5a
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash kernel/sched/

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/fair.c:28:
   In file included from include/linux/highmem.h:12:
   In file included from include/linux/hardirq.h:11:
   In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
   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/hexagon/include/asm/io.h:334:
   include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           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]
           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'
   #define __le16_to_cpu(x) ((__force __u16)(__le16)(x))
                                                     ^
   In file included from kernel/sched/fair.c:28:
   In file included from include/linux/highmem.h:12:
   In file included from include/linux/hardirq.h:11:
   In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
   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/hexagon/include/asm/io.h:334:
   include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           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'
   #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
                                                     ^
   In file included from kernel/sched/fair.c:28:
   In file included from include/linux/highmem.h:12:
   In file included from include/linux/hardirq.h:11:
   In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1:
   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/hexagon/include/asm/io.h:334:
   include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic]
           __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]
           __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]
           __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr);
                                                         ~~~~~~~~~~ ^
>> kernel/sched/fair.c:4697:27: warning: overflow in expression; result is -129542144 with type 'long' [-Winteger-overflow]
           if ((s64)sleep_time > 60 * NSEC_PER_SEC)
                                    ^
   kernel/sched/fair.c:6078:6: warning: no previous prototype for function 'init_cfs_bandwidth' [-Wmissing-prototypes]
   void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
        ^
   kernel/sched/fair.c:6078:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
   ^
   static 
   kernel/sched/fair.c:12498:6: warning: no previous prototype for function 'free_fair_sched_group' [-Wmissing-prototypes]
   void free_fair_sched_group(struct task_group *tg) { }
        ^
   kernel/sched/fair.c:12498:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void free_fair_sched_group(struct task_group *tg) { }
   ^
   static 
   kernel/sched/fair.c:12500:5: warning: no previous prototype for function 'alloc_fair_sched_group' [-Wmissing-prototypes]
   int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
       ^
   kernel/sched/fair.c:12500:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
   ^
   static 
   kernel/sched/fair.c:12505:6: warning: no previous prototype for function 'online_fair_sched_group' [-Wmissing-prototypes]
   void online_fair_sched_group(struct task_group *tg) { }
        ^
   kernel/sched/fair.c:12505:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void online_fair_sched_group(struct task_group *tg) { }
   ^
   static 
   kernel/sched/fair.c:12507:6: warning: no previous prototype for function 'unregister_fair_sched_group' [-Wmissing-prototypes]
   void unregister_fair_sched_group(struct task_group *tg) { }
        ^
   kernel/sched/fair.c:12507:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void unregister_fair_sched_group(struct task_group *tg) { }
   ^
   static 
   kernel/sched/fair.c:535:20: warning: unused function 'list_del_leaf_cfs_rq' [-Wunused-function]
   static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq)
                      ^
   kernel/sched/fair.c:556:19: warning: unused function 'tg_is_idle' [-Wunused-function]
   static inline int tg_is_idle(struct task_group *tg)
                     ^
   kernel/sched/fair.c:6051:20: warning: unused function 'cfs_bandwidth_used' [-Wunused-function]
   static inline bool cfs_bandwidth_used(void)
                      ^
   kernel/sched/fair.c:6059:20: warning: unused function 'sync_throttle' [-Wunused-function]
   static inline void sync_throttle(struct task_group *tg, int cpu) {}
                      ^
   kernel/sched/fair.c:6084:37: warning: unused function 'tg_cfs_bandwidth' [-Wunused-function]
   static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
                                       ^
   kernel/sched/fair.c:6088:20: warning: unused function 'destroy_cfs_bandwidth' [-Wunused-function]
   static inline void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
                      ^
   18 warnings generated.


vim +/long +4697 kernel/sched/fair.c

  4654	
  4655	static void
  4656	place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
  4657	{
  4658		u64 vruntime = cfs_rq->min_vruntime;
  4659		u64 sleep_time;
  4660	
  4661		/*
  4662		 * The 'current' period is already promised to the current tasks,
  4663		 * however the extra weight of the new task will slow them down a
  4664		 * little, place the new task so that it fits in the slot that
  4665		 * stays open at the end.
  4666		 */
  4667		if (initial && sched_feat(START_DEBIT))
  4668			vruntime += sched_vslice(cfs_rq, se);
  4669	
  4670		/* sleeps up to a single latency don't count. */
  4671		if (!initial) {
  4672			unsigned long thresh;
  4673	
  4674			if (se_is_idle(se))
  4675				thresh = sysctl_sched_min_granularity;
  4676			else
  4677				thresh = sysctl_sched_latency;
  4678	
  4679			/*
  4680			 * Halve their sleep time's effect, to allow
  4681			 * for a gentler effect of sleepers:
  4682			 */
  4683			if (sched_feat(GENTLE_FAIR_SLEEPERS))
  4684				thresh >>= 1;
  4685	
  4686			vruntime -= thresh;
  4687		}
  4688	
  4689		/*
  4690		 * Pull vruntime of the entity being placed to the base level of
  4691		 * cfs_rq, to prevent boosting it if placed backwards.  If the entity
  4692		 * slept for a long time, don't even try to compare its vruntime with
  4693		 * the base as it may be too far off and the comparison may get
  4694		 * inversed due to s64 overflow.
  4695		 */
  4696		sleep_time = rq_clock_task(rq_of(cfs_rq)) - se->exec_start;
> 4697		if ((s64)sleep_time > 60 * NSEC_PER_SEC)
  4698			se->vruntime = vruntime;
  4699		else
  4700			se->vruntime = max_vruntime(se->vruntime, vruntime);
  4701	}
  4702	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests

  parent reply	other threads:[~2023-01-28  7:46 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-01-27 16:32 [PATCH] sched/fair: sanitize vruntime of entity being placed Roman Kagan
2023-01-28  6:42 ` kernel test robot
2023-01-28  7:45 ` kernel test robot [this message]
2023-01-28 10:41 ` Zhang Qiao
2023-01-28 17:27 ` Chen Yu
2023-01-29  1:27   ` Zhang Qiao
2023-01-30 13:15     ` Chen Yu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=202301281536.CiaoBlBO-lkp@intel.com \
    --to=lkp@intel.com \
    --cc=bristot@redhat.com \
    --cc=bsegall@google.com \
    --cc=dietmar.eggemann@arm.com \
    --cc=juri.lelli@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=llvm@lists.linux.dev \
    --cc=longman@redhat.com \
    --cc=mgorman@suse.de \
    --cc=mingo@redhat.com \
    --cc=oe-kbuild-all@lists.linux.dev \
    --cc=peterz@infradead.org \
    --cc=rkagan@amazon.de \
    --cc=rostedt@goodmis.org \
    --cc=vincent.guittot@linaro.org \
    --cc=vschneid@redhat.com \
    --cc=zhangqiao22@huawei.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.