From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay2.corp.sgi.com [137.38.102.29]) by oss.sgi.com (Postfix) with ESMTP id E8C437F50 for ; Tue, 15 Apr 2014 23:18:41 -0500 (CDT) Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by relay2.corp.sgi.com (Postfix) with ESMTP id CF74F30407F for ; Tue, 15 Apr 2014 21:18:41 -0700 (PDT) Received: from mx2.suse.de (cantor2.suse.de [195.135.220.15]) by cuda.sgi.com with ESMTP id Iqpb414RH3g9ylok (version=TLSv1 cipher=AES256-SHA bits=256 verify=NO) for ; Tue, 15 Apr 2014 21:18:40 -0700 (PDT) From: NeilBrown Date: Wed, 16 Apr 2014 14:03:36 +1000 Subject: [PATCH 07/19] nfsd and VM: use PF_LESS_THROTTLE to avoid throttle in shrink_inactive_list. Message-ID: <20140416040336.10604.55772.stgit@notabene.brown> In-Reply-To: <20140416033623.10604.69237.stgit@notabene.brown> References: <20140416033623.10604.69237.stgit@notabene.brown> MIME-Version: 1.0 List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: linux-mm@kvack.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Cc: xfs@oss.sgi.com nfsd already uses PF_LESS_THROTTLE (and is the only user) to avoid throttling while dirtying pages. Use it also to avoid throttling while doing direct reclaim as this can stall nfsd in the same way. Also only set PF_LESS_THROTTLE when handling a 'write' request for a local connection. This is the only time when the throttling can cause a problem. In other cases we should throttle if the system is busy. Signed-off-by: NeilBrown --- fs/nfsd/nfssvc.c | 6 ------ fs/nfsd/vfs.c | 6 ++++++ mm/vmscan.c | 7 +++++-- 3 files changed, 11 insertions(+), 8 deletions(-) diff --git a/fs/nfsd/nfssvc.c b/fs/nfsd/nfssvc.c index 6af8bc2daf7d..cd24aa76e58d 100644 --- a/fs/nfsd/nfssvc.c +++ b/fs/nfsd/nfssvc.c @@ -593,12 +593,6 @@ nfsd(void *vrqstp) nfsdstats.th_cnt++; mutex_unlock(&nfsd_mutex); - /* - * We want less throttling in balance_dirty_pages() so that nfs to - * localhost doesn't cause nfsd to lock up due to all the client's - * dirty pages. - */ - current->flags |= PF_LESS_THROTTLE; set_freezable(); /* diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 6d7be3f80356..be2d7af3beee 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -913,6 +913,10 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, int stable = *stablep; int use_wgather; loff_t pos = offset; + unsigned int pflags; + + if (rqstp->rq_local) + current_set_flags_nested(&pflags, PF_LESS_THROTTLE); dentry = file->f_path.dentry; inode = dentry->d_inode; @@ -950,6 +954,8 @@ out_nfserr: err = 0; else err = nfserrno(host_err); + if (rqstp->rq_local) + current_restore_flags_nested(&pflags, PF_LESS_THROTTLE); return err; } diff --git a/mm/vmscan.c b/mm/vmscan.c index 05de3289d031..1b7c4e44f0a1 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1552,7 +1552,8 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, * implies that pages are cycling through the LRU faster than * they are written so also forcibly stall. */ - if (nr_unqueued_dirty == nr_taken || nr_immediate) + if ((nr_unqueued_dirty == nr_taken || nr_immediate) + && !current_test_flags(PF_LESS_THROTTLE)) congestion_wait(BLK_RW_ASYNC, HZ/10); } @@ -1561,7 +1562,9 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec, * is congested. Allow kswapd to continue until it starts encountering * unqueued dirty pages or cycling through the LRU too quickly. */ - if (!sc->hibernation_mode && !current_is_kswapd()) + if (!sc->hibernation_mode && + !current_is_kswapd() && + !current_test_flags(PF_LESS_THROTTLE)) wait_iff_congested(zone, BLK_RW_ASYNC, HZ/10); trace_mm_vmscan_lru_shrink_inactive(zone->zone_pgdat->node_id, _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs