From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f72.google.com (mail-wm0-f72.google.com [74.125.82.72]) by kanga.kvack.org (Postfix) with ESMTP id A46E56B0069 for ; Mon, 30 Oct 2017 09:10:17 -0400 (EDT) Received: by mail-wm0-f72.google.com with SMTP id y7so5942379wmd.18 for ; Mon, 30 Oct 2017 06:10:17 -0700 (PDT) Received: from mx2.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id 38si10520525wry.273.2017.10.30.06.10.16 for (version=TLS1 cipher=AES128-SHA bits=128/128); Mon, 30 Oct 2017 06:10:16 -0700 (PDT) Date: Mon, 30 Oct 2017 14:10:16 +0100 From: Jan Kara Subject: Re: [PATCH 3/4] bdi: add error handle for bdi_debug_register Message-ID: <20171030131016.GI23278@quack2.suse.cz> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: weiping zhang Cc: axboe@kernel.dk, jack@suse.cz, linux-block@vger.kernel.org, linux-mm@kvack.org On Fri 27-10-17 01:36:14, weiping zhang wrote: > In order to make error handle more cleaner we call bdi_debug_register > before set state to WB_registered, that we can avoid call bdi_unregister > in release_bdi(). > > Signed-off-by: weiping zhang > --- > mm/backing-dev.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/mm/backing-dev.c b/mm/backing-dev.c > index e9d6a1ede12b..54396d53f471 100644 > --- a/mm/backing-dev.c > +++ b/mm/backing-dev.c > @@ -893,10 +893,13 @@ int bdi_register_va(struct backing_dev_info *bdi, const char *fmt, va_list args) > if (IS_ERR(dev)) > return PTR_ERR(dev); > > + if (bdi_debug_register(bdi, dev_name(dev))) { > + device_destroy(bdi_class, dev->devt); > + return -ENOMEM; > + } > cgwb_bdi_register(bdi); > bdi->dev = dev; > > - bdi_debug_register(bdi, dev_name(dev)); > set_bit(WB_registered, &bdi->wb.state); > > spin_lock_bh(&bdi_lock); > @@ -916,6 +919,8 @@ int bdi_register(struct backing_dev_info *bdi, const char *fmt, ...) > va_start(args, fmt); > ret = bdi_register_va(bdi, fmt, args); > va_end(args); > + if (ret) > + bdi_put(bdi); Why do you drop bdi reference here in case of error? We didn't do it previously if bdi_register_va() failed for other reasons... Honza -- Jan Kara SUSE Labs, CR -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org