From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: linux-nfs-owner@vger.kernel.org Received: from cantor2.suse.de ([195.135.220.15]:59296 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756080Ab2FTJiS (ORCPT ); Wed, 20 Jun 2012 05:38:18 -0400 From: Mel Gorman To: Andrew Morton Cc: Linux-MM , Linux-Netdev , Linux-NFS , LKML , David Miller , Trond Myklebust , Neil Brown , Christoph Hellwig , Peter Zijlstra , Mike Christie , Eric B Munson , Mel Gorman Subject: [PATCH 11/12] nfs: Prevent page allocator recursions with swap over NFS. Date: Wed, 20 Jun 2012 10:38:00 +0100 Message-Id: <1340185081-22525-12-git-send-email-mgorman@suse.de> In-Reply-To: <1340185081-22525-1-git-send-email-mgorman@suse.de> References: <1340185081-22525-1-git-send-email-mgorman@suse.de> Sender: linux-nfs-owner@vger.kernel.org List-ID: GFP_NOFS is _more_ permissive than GFP_NOIO in that it will initiate IO, just not of any filesystem data. The problem is that previously NOFS was correct because that avoids recursion into the NFS code. With swap-over-NFS, it is no longer correct as swap IO can lead to this recursion. Signed-off-by: Peter Zijlstra Signed-off-by: Mel Gorman --- fs/nfs/pagelist.c | 2 +- fs/nfs/write.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c index 9ef8b3c..7de1646 100644 --- a/fs/nfs/pagelist.c +++ b/fs/nfs/pagelist.c @@ -70,7 +70,7 @@ void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos) static inline struct nfs_page * nfs_page_alloc(void) { - struct nfs_page *p = kmem_cache_zalloc(nfs_page_cachep, GFP_KERNEL); + struct nfs_page *p = kmem_cache_zalloc(nfs_page_cachep, GFP_NOIO); if (p) INIT_LIST_HEAD(&p->wb_list); return p; diff --git a/fs/nfs/write.c b/fs/nfs/write.c index f45b9ca..6f90681 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -52,7 +52,7 @@ static mempool_t *nfs_commit_mempool; struct nfs_commit_data *nfs_commitdata_alloc(void) { - struct nfs_commit_data *p = mempool_alloc(nfs_commit_mempool, GFP_NOFS); + struct nfs_commit_data *p = mempool_alloc(nfs_commit_mempool, GFP_NOIO); if (p) { memset(p, 0, sizeof(*p)); @@ -70,7 +70,7 @@ EXPORT_SYMBOL_GPL(nfs_commit_free); struct nfs_write_header *nfs_writehdr_alloc(void) { - struct nfs_write_header *p = mempool_alloc(nfs_wdata_mempool, GFP_NOFS); + struct nfs_write_header *p = mempool_alloc(nfs_wdata_mempool, GFP_NOIO); if (p) { struct nfs_pgio_header *hdr = &p->header; -- 1.7.9.2