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To: Christoph Hellwig Cc: kernel test robot , Damien Le Moal , oe-kbuild-all@lists.linux.dev, linux-kernel@vger.kernel.org, Hannes Reinecke , "Martin K. Petersen" , Bart Van Assche References: <202411050650.ilIZa8S7-lkp@intel.com> <20241105153422.GA7132@lst.de> <20241105153733.GA7219@lst.de> Content-Language: en-US From: Jens Axboe In-Reply-To: <20241105153733.GA7219@lst.de> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 11/5/24 8:37 AM, Christoph Hellwig wrote: > On Tue, Nov 05, 2024 at 08:36:33AM -0700, Jens Axboe wrote: >> On 11/5/24 8:34 AM, Christoph Hellwig wrote: >>> On Tue, Nov 05, 2024 at 06:52:25AM +0800, kernel test robot wrote: >>>>>> block/blk-zoned.c:579:5-24: WARNING: atomic_dec_and_test variation before object free at line 583. >>> >>> Does anyone know what this warning is supposed to mean? >> >> It's supposed to mean "use refcount_t for things like this". > > Have we finally resolved the performance problems with refcount_t for > fast path operations? I mean it's closer, but it's still slower. Will always be so. Does it matter for zoned devices? Probably not. I don't think it matters for this case. It's not like the ref itself is something that is user controllable in terms of being able to get anywhere near an overflow. -- Jens Axboe