On Apr 23, 2014, at 8:20 AM, Boaz Harrosh <bharrosh@xxxxxxxxxxx> wrote:
> On 04/23/2014 12:29 AM, Weston Andros Adamson wrote:
>> Now that pg_test can change the size of the request (by returning a non-zero
>> size smaller than the request), pg_test functions that call other
>> pg_test functions must return the minimum of the result - or 0 if any fail.
>>
>> Also clean up the logic of some pg_test functions so that all checks are
>> for contitions where coalescing is not possible.
>>
>> Signed-off-by: Weston Andros Adamson <dros@xxxxxxxxxxxxxxx>
>> ---
>> fs/nfs/nfs4filelayout.c | 27 ++++++++++++++-------------
>> fs/nfs/objlayout/objio_osd.c | 12 ++++++++----
>> fs/nfs/pnfs.c | 15 ++++++++++-----
>> 3 files changed, 32 insertions(+), 22 deletions(-)
>>
>> diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
>> index 3b32c95..cfd76bd 100644
>> --- a/fs/nfs/nfs4filelayout.c
>> +++ b/fs/nfs/nfs4filelayout.c
>> @@ -930,26 +930,27 @@ static size_t
>> filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
>> struct nfs_page *req)
>> {
>> + unsigned int size;
>> u64 p_stripe, r_stripe;
>> u32 stripe_unit;
>>
>> - if (!pnfs_generic_pg_test(pgio, prev, req) ||
>> - !nfs_generic_pg_test(pgio, prev, req))
>> + /* calls nfs_generic_pg_test */
>> + size = pnfs_generic_pg_test(pgio, prev, req);
>> + if (!size)
>> return 0;
>>
>> - if (!prev)
>> - return req->wb_bytes;
>> + if (prev) {
>> + p_stripe = (u64)req_offset(prev);
>> + r_stripe = (u64)req_offset(req);
>> + stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
>>
>> - p_stripe = (u64)req_offset(prev);
>> - r_stripe = (u64)req_offset(req);
>> - stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
>> + do_div(p_stripe, stripe_unit);
>> + do_div(r_stripe, stripe_unit);
>>
>> - do_div(p_stripe, stripe_unit);
>> - do_div(r_stripe, stripe_unit);
>> -
>> - if (p_stripe == r_stripe)
>> - return req->wb_bytes;
>> - return 0;
>> + if (p_stripe != r_stripe)
>> + return 0;
>> + }
>> + return min(size, req->wb_bytes);
>> }
>>
>> static void
>> diff --git a/fs/nfs/objlayout/objio_osd.c b/fs/nfs/objlayout/objio_osd.c
>> index c20352a..31de29e 100644
>> --- a/fs/nfs/objlayout/objio_osd.c
>> +++ b/fs/nfs/objlayout/objio_osd.c
>> @@ -571,13 +571,17 @@ int objio_write_pagelist(struct nfs_write_data *wdata, int how)
>> static size_t objio_pg_test(struct nfs_pageio_descriptor *pgio,
>> struct nfs_page *prev, struct nfs_page *req)
>> {
>> - if (!pnfs_generic_pg_test(pgio, prev, req))
>> + unsigned int size;
>> +
>> + size = pnfs_generic_pg_test(pgio, prev, req);
>> +
>> + if (!size)
>> return 0;
>>
>> - if (pgio->pg_count + req->wb_bytes <=
>> + if (pgio->pg_count + req->wb_bytes >
>> (unsigned long)pgio->pg_layout_private)
>> - return req->wb_bytes;
>> - return 0;
>> + return 0;
>
> objio_osd can enjoy the new facility by returning the
> remainder here:
>
> max_io = (unsigned long)pgio->pg_layout_private);
>
> wb_bytes = min(size, req->wb_bytes);
>
> if (pgio->pg_count + req->wb_bytes > max_io)
> wb_bytes = max_io - pgio->pg_count;
>
> return wb_bytes;
>
> Which reminds me that this code sucks and I need to fix it. I will do
> so after you send your changes.
>
> [I promise to test these guys soon. Can you please put them on a public tree?]
Yes, I’ll put something up on linux-nfs.org.
Thanks!
-dros
>
> Thanks
> Boaz
>
>> + return min(size, req->wb_bytes);
>> }
>>
>> static void objio_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
>> diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
>> index 6201bf6..7c89385 100644
>> --- a/fs/nfs/pnfs.c
>> +++ b/fs/nfs/pnfs.c
>> @@ -1469,8 +1469,12 @@ size_t
>> pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
>> struct nfs_page *req)
>> {
>> - if (pgio->pg_lseg == NULL)
>> - return nfs_generic_pg_test(pgio, prev, req);
>> + unsigned int size;
>> +
>> + size = nfs_generic_pg_test(pgio, prev, req);
>> +
>> + if (!size)
>> + return 0;
>>
>> /*
>> * Test if a nfs_page is fully contained in the pnfs_layout_range.
>> @@ -1486,10 +1490,11 @@ pnfs_generic_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
>> * first byte that lies outside the pnfs_layout_range. FIXME?
>> *
>> */
>> - if (req_offset(req) < end_offset(pgio->pg_lseg->pls_range.offset,
>> + if (req_offset(req) >= end_offset(pgio->pg_lseg->pls_range.offset,
>> pgio->pg_lseg->pls_range.length))
>> - return req->wb_bytes;
>> - return 0;
>> + return 0;
>> +
>> + return min(size, req->wb_bytes);
>> }
>> EXPORT_SYMBOL_GPL(pnfs_generic_pg_test);
--
To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
