From: Boaz Harrosh Subject: Re: [PATCH 13/24] pnfs_submit: read path changeover Date: Wed, 09 Jun 2010 22:19:18 +0300 Message-ID: <4C0FE936.2090901@panasas.com> References: <1275970761-31806-1-git-send-email-iisaman@netapp.com> <1275970761-31806-2-git-send-email-iisaman@netapp.com> <1275970761-31806-3-git-send-email-iisaman@netapp.com> <1275970761-31806-4-git-send-email-iisaman@netapp.com> <1275970761-31806-5-git-send-email-iisaman@netapp.com> <1275970761-31806-6-git-send-email-iisaman@netapp.com> <1275970761-31806-7-git-send-email-iisaman@netapp.com> <1275970761-31806-8-git-send-email-iisaman@netapp.com> <1275970761-31806-9-git-send-email-iisaman@netapp.com> <1275970761-31806-10-git-send-email-iisaman@netapp.com> <1275970761-31806-11-git-send-email-iisaman@netapp.com> <1275970761-31806-12-git-send-email-iisaman@netapp.com> <1275970761-31806-13-git-send-email-iisaman@netapp.com> <1275970761-31806-14-git-send-email-iisaman@netapp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: linux-nfs@vger.kernel.org To: Fred Isaman Return-path: Received: from daytona.panasas.com ([67.152.220.89]:63384 "EHLO daytona.int.panasas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756515Ab0FITTV (ORCPT ); Wed, 9 Jun 2010 15:19:21 -0400 In-Reply-To: <1275970761-31806-14-git-send-email-iisaman@netapp.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On 06/08/2010 07:19 AM, Fred Isaman wrote: > Change readpages path to only call LAYOUTGET once. > > Signed-off-by: Fred Isaman > --- > fs/nfs/pagelist.c | 2 ++ > fs/nfs/pnfs.c | 37 +++++++------------------------------ > fs/nfs/pnfs.h | 25 ++++++++++++++++--------- > 3 files changed, 25 insertions(+), 39 deletions(-) > > diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c > index ed647b9..c3e5a1f 100644 > --- a/fs/nfs/pagelist.c > +++ b/fs/nfs/pagelist.c > @@ -253,6 +253,8 @@ static int nfs_can_coalesce_requests(struct nfs_page *prev, > return 0; > if (prev->wb_pgbase + prev->wb_bytes != PAGE_CACHE_SIZE) > return 0; > + if (req->wb_lseg != prev->wb_lseg) > + return 0; > #ifdef CONFIG_NFS_V4_1 > if (pgio->pg_test && !pgio->pg_test(pgio, prev, req)) > return 0; > diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c > index 2b5f6fc..692a18e 100644 > --- a/fs/nfs/pnfs.c > +++ b/fs/nfs/pnfs.c > @@ -1689,7 +1689,7 @@ pnfs_readpages(struct nfs_read_data *rdata) > { > struct nfs_readargs *args = &rdata->args; > struct inode *inode = rdata->inode; > - int numpages, status, pgcount, temp; > + int numpages, pgcount, temp; > struct nfs_server *nfss = NFS_SERVER(inode); > struct nfs_inode *nfsi = NFS_I(inode); > struct pnfs_layout_segment *lseg; > @@ -1701,19 +1701,8 @@ pnfs_readpages(struct nfs_read_data *rdata) > args->count, > args->offset); > > - /* Retrieve and set layout if not allready cached */ > - status = _pnfs_update_layout(inode, > - args->context, > - args->count, > - args->offset, > - IOMODE_READ, > - &lseg); > - if (status) { > - dprintk("%s: Updating layout failed (%d), retry with NFS \n", > - __func__, status); > - trypnfs = PNFS_NOT_ATTEMPTED; > - goto out; > - } > + lseg = rdata->req->wb_lseg; > + get_lseg(lseg); > > /* Determine number of pages. */ > pgcount = args->pgbase + args->count; > @@ -1740,7 +1729,6 @@ pnfs_readpages(struct nfs_read_data *rdata) > rdata->pdata.lseg = NULL; > put_lseg(lseg); > } > - out: > dprintk("%s End (trypnfs:%d)\n", __func__, trypnfs); > return trypnfs; > } > @@ -1749,21 +1737,10 @@ enum pnfs_try_status > _pnfs_try_to_read_data(struct nfs_read_data *data, > const struct rpc_call_ops *call_ops) > { > - struct inode *ino = data->inode; > - struct nfs_server *nfss = NFS_SERVER(ino); > - > - dprintk("--> %s\n", __func__); > - /* Only create an rpc request if utilizing NFSv4 I/O */ > - if (!pnfs_enabled_sb(nfss) || > - !nfss->pnfs_curr_ld->ld_io_ops->read_pagelist) { > - dprintk("<-- %s: not using pnfs\n", __func__); > - return PNFS_NOT_ATTEMPTED; > - } else { > - dprintk("%s: Utilizing pNFS I/O\n", __func__); > - data->pdata.call_ops = call_ops; > - data->pdata.pnfs_error = 0; > - return pnfs_readpages(data); > - } Wahoo, nice stuff Ha By now this can go into it's only caller. (And caller de-inlined, what was that all about) > + dprintk("%s: Utilizing pNFS I/O\n", __func__); > + data->pdata.call_ops = call_ops; > + data->pdata.pnfs_error = 0; > + return pnfs_readpages(data); > } > > enum pnfs_try_status > diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h > index 6326ed5..816ebe1 100644 > --- a/fs/nfs/pnfs.h > +++ b/fs/nfs/pnfs.h > @@ -94,22 +94,29 @@ static inline int pnfs_enabled_sb(struct nfs_server *nfss) > return nfss->pnfs_curr_ld != NULL; > } > > +static inline void _pnfs_clear_lseg_from_pages(struct list_head *head) > +{ > + struct nfs_page *req; > + > + list_for_each_entry(req, head, wb_list) { > + put_lseg(req->wb_lseg); > + req->wb_lseg = NULL; > + } > +} > + > static inline enum pnfs_try_status > pnfs_try_to_read_data(struct nfs_read_data *data, > const struct rpc_call_ops *call_ops) Don't think this needs to be inline, whats the point? > { > - struct inode *inode = data->inode; > - struct nfs_server *nfss = NFS_SERVER(inode); > enum pnfs_try_status ret; > > - /* FIXME: read_pagelist should probably be mandated */ > - if (PNFS_EXISTS_LDIO_OP(nfss, read_pagelist)) > - ret = _pnfs_try_to_read_data(data, call_ops); > - else > - ret = PNFS_NOT_ATTEMPTED; > - > + if (!data->req->wb_lseg) > + return PNFS_NOT_ATTEMPTED; > + ret = _pnfs_try_to_read_data(data, call_ops); > if (ret == PNFS_ATTEMPTED) > - nfs_inc_stats(inode, NFSIOS_PNFS_READ); > + nfs_inc_stats(data->inode, NFSIOS_PNFS_READ); > + else > + _pnfs_clear_lseg_from_pages(&data->pages); > return ret; > } > Boaz