Re: [PATCH 13/24] pnfs_submit: read path changeover

Boaz Harrosh
2010-06-09T19:39:17Z

On 06/09/2010 10:29 PM, Fred Isaman wrote:
> On Wed, Jun 9, 2010 at 3:19 PM, Boaz Harrosh <bharrosh@panasas.com> wrote:
>> On 06/08/2010 07:19 AM, Fred Isaman wrote:
>>> Change readpages path to only call LAYOUTGET once.
>>>
>>> Signed-off-by: Fred Isaman <iisaman@netapp.com>
>>> ---
>>> 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?
>>
>
> The point is that it is in the header file, not a c file.
>

That's what I meant. Why is it in the header file. Why not
in .c file and declared.

> Fred
>

(-Bz

>>> {
>>> - 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
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>