From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de ([195.135.220.15]:60230 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751348AbdHXK4h (ORCPT ); Thu, 24 Aug 2017 06:56:37 -0400 Date: Thu, 24 Aug 2017 12:56:35 +0200 From: Michal Hocko Subject: Re: [PATCH] xfs: Drop setting redundant PF_KSWAPD in kswapd context Message-ID: <20170824105635.GA5965@dhcp22.suse.cz> References: <20170824104247.8288-1-khandual@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170824104247.8288-1-khandual@linux.vnet.ibm.com> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Anshuman Khandual Cc: linux-mm@kvack.org, linux-xfs@vger.kernel.org, linux-kernel@vger.kernel.org, dchinner@redhat.com, bfoster@redhat.com, sandeen@sandeen.net On Thu 24-08-17 16:12:47, Anshuman Khandual wrote: > xfs_btree_split() calls xfs_btree_split_worker() with args.kswapd set > if current->flags alrady has PF_KSWAPD. Hence we should not again add > PF_KSWAPD into the current flags inside kswapd context. So drop this > redundant flag addition. I am not familiar with the code but your change seems incorect. The whole point of args->kswapd is to convey the kswapd context to the worker which is obviously running in a different context. So this patch loses the kswapd context. > Signed-off-by: Anshuman Khandual > --- > fs/xfs/libxfs/xfs_btree.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c > index e0bcc4a..b3c85e3 100644 > --- a/fs/xfs/libxfs/xfs_btree.c > +++ b/fs/xfs/libxfs/xfs_btree.c > @@ -2895,7 +2895,7 @@ struct xfs_btree_split_args { > * in any way. > */ > if (args->kswapd) > - new_pflags |= PF_MEMALLOC | PF_SWAPWRITE | PF_KSWAPD; > + new_pflags |= PF_MEMALLOC | PF_SWAPWRITE; > > current_set_flags_nested(&pflags, new_pflags); > > -- > 1.8.5.2 -- Michal Hocko SUSE Labs