From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752550AbaCFI0x (ORCPT ); Thu, 6 Mar 2014 03:26:53 -0500 Received: from lgeamrelo01.lge.com ([156.147.1.125]:56208 "EHLO LGEAMRELO01.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752504AbaCFI0w (ORCPT ); Thu, 6 Mar 2014 03:26:52 -0500 X-AuditID: 9c93017d-b7c89ae000006ae1-dc-531831498e5b Date: Thu, 6 Mar 2014 17:26:53 +0900 From: Minchan Kim To: Sergey Senozhatsky Cc: Andrew Morton , Jerome Marchand , Nitin Gupta , linux-kernel@vger.kernel.org, Sasha Levin Subject: Re: [PATCH] zram: move comp allocation out of init_lock Message-ID: <20140306082653.GC14287@bbox> References: <1393927856-23434-1-git-send-email-sergey.senozhatsky@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1393927856-23434-1-git-send-email-sergey.senozhatsky@gmail.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Sergey, On Tue, Mar 04, 2014 at 01:10:56PM +0300, Sergey Senozhatsky wrote: > While fixing lockdep spew of ->init_lock reported by Sasha Levin [1], Minchan > Kim noted [2] that it's better to move compression backend allocation (using > GPF_KERNEL) out of the ->init_lock lock, same way as with zram_meta_alloc(), > in order to prevent the same lockdep spew. > > [1] https://lkml.org/lkml/2014/2/27/337 > [2] https://lkml.org/lkml/2014/3/3/32 > > Cc: Sasha Levin > Reported-by: Minchan Kim > Signed-off-by: Sergey Senozhatsky Thanks for looking. > --- > drivers/block/zram/zram_drv.c | 27 +++++++++++++++------------ > 1 file changed, 15 insertions(+), 12 deletions(-) > > diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c > index 15d46f2..e4d536b 100644 > --- a/drivers/block/zram/zram_drv.c > +++ b/drivers/block/zram/zram_drv.c > @@ -580,9 +580,10 @@ static ssize_t disksize_store(struct device *dev, > struct device_attribute *attr, const char *buf, size_t len) > { > u64 disksize; > + struct zcomp *comp; > struct zram_meta *meta; > struct zram *zram = dev_to_zram(dev); > - int err; > + int err = -EINVAL; > > disksize = memparse(buf, NULL); > if (!disksize) > @@ -593,30 +594,32 @@ static ssize_t disksize_store(struct device *dev, > if (!meta) > return -ENOMEM; > > + comp = zcomp_create(zram->compressor, zram->max_comp_streams); > + if (!comp) { > + pr_info("Cannot initialise %s compressing backend\n", > + zram->compressor); -ENOMEM? Otherwise, Acked-by: Minchan Kim > + goto out_cleanup; > + } > + > down_write(&zram->init_lock); > if (init_done(zram)) { > + up_write(&zram->init_lock); > pr_info("Cannot change disksize for initialized device\n"); > err = -EBUSY; > - goto out_free_meta; > - } > - > - zram->comp = zcomp_create(zram->compressor, zram->max_comp_streams); > - if (!zram->comp) { > - pr_info("Cannot initialise %s compressing backend\n", > - zram->compressor); > - err = -EINVAL; > - goto out_free_meta; > + goto out_cleanup; > } > > zram->meta = meta; > + zram->comp = comp; > zram->disksize = disksize; > set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT); > up_write(&zram->init_lock); > > return len; > > -out_free_meta: > - up_write(&zram->init_lock); > +out_cleanup: > + if (comp) > + zcomp_destroy(comp); > zram_meta_free(meta); > return err; > } > -- > 1.9.0.382.g7f3562c > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- Kind regards, Minchan Kim