Re: [PATCH v2 05/11] smp: replace smp_call_function_single_async() with smp_call_private()

From: kernel test robot <lkp@intel.com>
To: Donghai Qiao <dqiao@redhat.com>,
	akpm@linux-foundation.org, sfr@canb.auug.org.au, arnd@arndb.de,
	peterz@infradead.org, heying24@huawei.com,
	andriy.shevchenko@linux.intel.com, axboe@kernel.dk,
	rdunlap@infradead.org, tglx@linutronix.de, gor@linux.ibm.com
Cc: llvm@lists.linux.dev, kbuild-all@lists.01.org,
	donghai.w.qiao@gmail.com, linux-kernel@vger.kernel.org,
	Donghai Qiao <dqiao@redhat.com>
Subject: Re: [PATCH v2 05/11] smp: replace smp_call_function_single_async() with  smp_call_private()
Date: Sat, 23 Apr 2022 15:30:18 +0800	[thread overview]
Message-ID: <202204231532.nXbSK9Tk-lkp@intel.com> (raw)
In-Reply-To: <20220422200040.93813-6-dqiao@redhat.com>

Hi Donghai,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on powerpc/next]
[also build test WARNING on rafael-pm/linux-next linus/master v5.18-rc3 next-20220422]
[cannot apply to tip/x86/core]
[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]

url:    https://github.com/intel-lab-lkp/linux/commits/Donghai-Qiao/smp-cross-CPU-call-interface/20220423-060436
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: i386-randconfig-a002 (https://download.01.org/0day-ci/archive/20220423/202204231532.nXbSK9Tk-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 5bd87350a5ae429baf8f373cb226a57b62f87280)
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/3b8a90029bebdb77e2d5c0cd16f371e83d8ed2e8
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Donghai-Qiao/smp-cross-CPU-call-interface/20220423-060436
        git checkout 3b8a90029bebdb77e2d5c0cd16f371e83d8ed2e8
        # 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=i386 SHELL=/bin/bash

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

All warnings (new ones prefixed by >>):

>> block/blk-mq.c:1065:39: warning: passing 4-byte aligned argument to 16-byte aligned parameter 2 of 'smp_call_private' may result in an unaligned pointer access [-Walign-mismatch]
                   smp_call_function_single_async(cpu, &rq->csd);
                                                       ^
   1 warning generated.

vim +/smp_call_private +1065 block/blk-mq.c

963395269c7586 Christoph Hellwig         2020-06-11  1055  
f9ab49184af093 Sebastian Andrzej Siewior 2021-01-23  1056  static void blk_mq_complete_send_ipi(struct request *rq)
f9ab49184af093 Sebastian Andrzej Siewior 2021-01-23  1057  {
f9ab49184af093 Sebastian Andrzej Siewior 2021-01-23  1058  	struct llist_head *list;
f9ab49184af093 Sebastian Andrzej Siewior 2021-01-23  1059  	unsigned int cpu;
f9ab49184af093 Sebastian Andrzej Siewior 2021-01-23  1060  
f9ab49184af093 Sebastian Andrzej Siewior 2021-01-23  1061  	cpu = rq->mq_ctx->cpu;
f9ab49184af093 Sebastian Andrzej Siewior 2021-01-23  1062  	list = &per_cpu(blk_cpu_done, cpu);
f9ab49184af093 Sebastian Andrzej Siewior 2021-01-23  1063  	if (llist_add(&rq->ipi_list, list)) {
f9ab49184af093 Sebastian Andrzej Siewior 2021-01-23  1064  		INIT_CSD(&rq->csd, __blk_mq_complete_request_remote, rq);
f9ab49184af093 Sebastian Andrzej Siewior 2021-01-23 @1065  		smp_call_function_single_async(cpu, &rq->csd);
f9ab49184af093 Sebastian Andrzej Siewior 2021-01-23  1066  	}
f9ab49184af093 Sebastian Andrzej Siewior 2021-01-23  1067  }
f9ab49184af093 Sebastian Andrzej Siewior 2021-01-23  1068  

-- 
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https://01.org/lkp