From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0D1BFC3A5A6 for ; Mon, 23 Sep 2019 10:10:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DF47120882 for ; Mon, 23 Sep 2019 10:10:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405759AbfIWKK3 (ORCPT ); Mon, 23 Sep 2019 06:10:29 -0400 Received: from mx2.suse.de ([195.135.220.15]:47368 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2405672AbfIWKK3 (ORCPT ); Mon, 23 Sep 2019 06:10:29 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id A0A9FAF65; Mon, 23 Sep 2019 10:10:27 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id 516001E4669; Mon, 23 Sep 2019 12:10:42 +0200 (CEST) Date: Mon, 23 Sep 2019 12:10:42 +0200 From: Jan Kara To: Goldwyn Rodrigues Cc: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-btrfs@vger.kernel.org, hch@infradead.org, andres@anarazel.de, david@fromorbit.com, riteshh@linux.ibm.com, linux-f2fs-devel@lists.sourceforge.net, Ted Tso , Goldwyn Rodrigues Subject: Re: [PATCH 2/3] ext4: fix inode rwsem regression Message-ID: <20190923101042.GA25332@quack2.suse.cz> References: <20190911093926.pfkkx25mffzeuo32@alap3.anarazel.de> <20190911164517.16130-1-rgoldwyn@suse.de> <20190911164517.16130-3-rgoldwyn@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190911164517.16130-3-rgoldwyn@suse.de> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Wed 11-09-19 11:45:16, Goldwyn Rodrigues wrote: > From: Goldwyn Rodrigues > > This is similar to 942491c9e6d6 ("xfs: fix AIM7 regression") > Apparently our current rwsem code doesn't like doing the trylock, then > lock for real scheme. So change our read/write methods to just do the > trylock for the RWF_NOWAIT case. > > Fixes: 728fbc0e10b7 ("ext4: nowait aio support") > Signed-off-by: Goldwyn Rodrigues Thanks for fixing this! The patch looks good to me. You can add: Reviewed-by: Jan Kara BTW, I've also added Ted as ext4 maintainer to CC. Honza > --- > fs/ext4/file.c | 17 +++++++++++------ > 1 file changed, 11 insertions(+), 6 deletions(-) > > diff --git a/fs/ext4/file.c b/fs/ext4/file.c > index 70b0438dbc94..d5b2d0cc325d 100644 > --- a/fs/ext4/file.c > +++ b/fs/ext4/file.c > @@ -40,11 +40,13 @@ static ssize_t ext4_dax_read_iter(struct kiocb *iocb, struct iov_iter *to) > struct inode *inode = file_inode(iocb->ki_filp); > ssize_t ret; > > - if (!inode_trylock_shared(inode)) { > - if (iocb->ki_flags & IOCB_NOWAIT) > + if (iocb->ki_flags & IOCB_NOWAIT) { > + if (!inode_trylock_shared(inode)) > return -EAGAIN; > + } else { > inode_lock_shared(inode); > } > + > /* > * Recheck under inode lock - at this point we are sure it cannot > * change anymore > @@ -190,11 +192,13 @@ ext4_dax_write_iter(struct kiocb *iocb, struct iov_iter *from) > struct inode *inode = file_inode(iocb->ki_filp); > ssize_t ret; > > - if (!inode_trylock(inode)) { > - if (iocb->ki_flags & IOCB_NOWAIT) > + if (iocb->ki_flags & IOCB_NOWAIT) { > + if (!inode_trylock(inode)) > return -EAGAIN; > + } else { > inode_lock(inode); > } > + > ret = ext4_write_checks(iocb, from); > if (ret <= 0) > goto out; > @@ -233,9 +237,10 @@ ext4_file_write_iter(struct kiocb *iocb, struct iov_iter *from) > if (!o_direct && (iocb->ki_flags & IOCB_NOWAIT)) > return -EOPNOTSUPP; > > - if (!inode_trylock(inode)) { > - if (iocb->ki_flags & IOCB_NOWAIT) > + if (iocb->ki_flags & IOCB_NOWAIT) { > + if (!inode_trylock(inode)) > return -EAGAIN; > + } else { > inode_lock(inode); > } > > -- > 2.16.4 > -- Jan Kara SUSE Labs, CR