From 94ad1c80e28f9700c84b4d28d1e5302ddf63a6fd Mon Sep 17 00:00:00 2001 From: Fred Isaman Date: Tue, 1 Mar 2011 01:34:14 +0000 Subject: NFSv4.1: coelesce across layout stripes Add a pg_test layout driver hook which is used to avoid coelescing I/O across layout stripes. Signed-off-by: Andy Adamson Signed-off-by: Andy Adamson Signed-off-by: Dean Hildebrand Signed-off-by: Fred Isaman Signed-off-by: Fred Isaman Signed-off-by: Benny Halevy Signed-off-by: Boaz Harrosh Signed-off-by: Oleg Drokin Signed-off-by: Tao Guo Signed-off-by: Trond Myklebust --- fs/nfs/pagelist.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) (limited to 'fs/nfs/pagelist.c') diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c index e1164e3f9e69..9b9a65c9bb4f 100644 --- a/fs/nfs/pagelist.c +++ b/fs/nfs/pagelist.c @@ -226,6 +226,7 @@ void nfs_pageio_init(struct nfs_pageio_descriptor *desc, desc->pg_doio = doio; desc->pg_ioflags = io_flags; desc->pg_error = 0; + desc->pg_lseg = NULL; } /** @@ -240,7 +241,8 @@ void nfs_pageio_init(struct nfs_pageio_descriptor *desc, * Return 'true' if this is the case, else return 'false'. */ static int nfs_can_coalesce_requests(struct nfs_page *prev, - struct nfs_page *req) + struct nfs_page *req, + struct nfs_pageio_descriptor *pgio) { if (req->wb_context->cred != prev->wb_context->cred) return 0; @@ -254,6 +256,12 @@ static int nfs_can_coalesce_requests(struct nfs_page *prev, return 0; if (prev->wb_pgbase + prev->wb_bytes != PAGE_CACHE_SIZE) return 0; + /* + * Non-whole file layouts need to check that req is inside of + * pgio->pg_lseg. + */ + if (pgio->pg_test && !pgio->pg_test(pgio, prev, req)) + return 0; return 1; } @@ -286,7 +294,7 @@ static int nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc, if (newlen > desc->pg_bsize) return 0; prev = nfs_list_entry(desc->pg_list.prev); - if (!nfs_can_coalesce_requests(prev, req)) + if (!nfs_can_coalesce_requests(prev, req, desc)) return 0; } else desc->pg_base = req->wb_pgbase; -- cgit v1.2.3