From b31268ac793fd300da66b9c28bbf0a200339ab96 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 21 Mar 2011 17:02:00 -0400 Subject: [PATCH] FS: Use stable writes when not doing a bulk flush If we're only doing a single write, and there are no other unstable writes being queued up, we might want to just flip to using a stable write RPC call. Reviewed-by: NeilBrown Signed-off-by: Trond Myklebust --- fs/nfs/pagelist.c | 3 +++ fs/nfs/write.c | 16 +++++++++++++--- include/linux/nfs_fs.h | 2 ++ include/linux/nfs_page.h | 1 + 4 files changed, 19 insertions(+), 3 deletions(-) diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c index 23e794410669..fd85618149a1 100644 --- a/fs/nfs/pagelist.c +++ b/fs/nfs/pagelist.c @@ -223,6 +223,7 @@ void nfs_pageio_init(struct nfs_pageio_descriptor *desc, desc->pg_count = 0; desc->pg_bsize = bsize; desc->pg_base = 0; + desc->pg_moreio = 0; desc->pg_inode = inode; desc->pg_doio = doio; desc->pg_ioflags = io_flags; @@ -335,9 +336,11 @@ int nfs_pageio_add_request(struct nfs_pageio_descriptor *desc, struct nfs_page *req) { while (!nfs_pageio_do_add_request(desc, req)) { + desc->pg_moreio = 1; nfs_pageio_doio(desc); if (desc->pg_error < 0) return 0; + desc->pg_moreio = 0; } return 1; } diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 47a3ad63e0d5..4d686ee53244 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -179,8 +179,8 @@ static int wb_priority(struct writeback_control *wbc) if (wbc->for_reclaim) return FLUSH_HIGHPRI | FLUSH_STABLE; if (wbc->for_kupdate || wbc->for_background) - return FLUSH_LOWPRI; - return 0; + return FLUSH_LOWPRI | FLUSH_COND_STABLE; + return FLUSH_COND_STABLE; } /* @@ -863,7 +863,7 @@ static int nfs_write_rpcsetup(struct nfs_page *req, data->args.context = get_nfs_open_context(req->wb_context); data->args.lock_context = req->wb_lock_context; data->args.stable = NFS_UNSTABLE; - if (how & FLUSH_STABLE) { + if (how & (FLUSH_STABLE | FLUSH_COND_STABLE)) { data->args.stable = NFS_DATA_SYNC; if (!nfs_need_commit(NFS_I(inode))) data->args.stable = NFS_FILE_SYNC; @@ -912,6 +912,12 @@ static int nfs_flush_multi(struct nfs_pageio_descriptor *desc) nfs_list_remove_request(req); + if ((desc->pg_ioflags & FLUSH_COND_STABLE) && + (desc->pg_moreio || NFS_I(desc->pg_inode)->ncommit || + desc->pg_count > wsize)) + desc->pg_ioflags &= ~FLUSH_COND_STABLE; + + nbytes = desc->pg_count; do { size_t len = min(nbytes, wsize); @@ -1002,6 +1008,10 @@ static int nfs_flush_one(struct nfs_pageio_descriptor *desc) if ((!lseg) && list_is_singular(&data->pages)) lseg = pnfs_update_layout(desc->pg_inode, req->wb_context, IOMODE_RW); + if ((desc->pg_ioflags & FLUSH_COND_STABLE) && + (desc->pg_moreio || NFS_I(desc->pg_inode)->ncommit)) + desc->pg_ioflags &= ~FLUSH_COND_STABLE; + /* Set up the argument struct */ ret = nfs_write_rpcsetup(req, data, &nfs_write_full_ops, desc->pg_count, 0, lseg, desc->pg_ioflags); out: diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h index f88522b10a38..cb2add401f25 100644 --- a/include/linux/nfs_fs.h +++ b/include/linux/nfs_fs.h @@ -33,6 +33,8 @@ #define FLUSH_STABLE 4 /* commit to stable storage */ #define FLUSH_LOWPRI 8 /* low priority background flush */ #define FLUSH_HIGHPRI 16 /* high priority memory reclaim flush */ +#define FLUSH_COND_STABLE 32 /* conditional stable write - only stable + * if everything fits in one RPC */ #ifdef __KERNEL__ diff --git a/include/linux/nfs_page.h b/include/linux/nfs_page.h index 90907ada6d52..92d54c81f51e 100644 --- a/include/linux/nfs_page.h +++ b/include/linux/nfs_page.h @@ -57,6 +57,7 @@ struct nfs_pageio_descriptor { size_t pg_count; size_t pg_bsize; unsigned int pg_base; + char pg_moreio; struct inode *pg_inode; int (*pg_doio)(struct nfs_pageio_descriptor *); -- 2.34.1