NFS: Add a count of the number of unstable writes carried by an inode
In order to know when we should do opportunistic commits of the unstable
writes, when the VM is doing a background flush, we add a field to count
the number of unstable writes.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 89e9831..aa5a83100 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1404,6 +1404,7 @@
INIT_LIST_HEAD(&nfsi->access_cache_inode_lru);
INIT_RADIX_TREE(&nfsi->nfs_page_tree, GFP_ATOMIC);
nfsi->npages = 0;
+ nfsi->ncommit = 0;
atomic_set(&nfsi->silly_count, 1);
INIT_HLIST_HEAD(&nfsi->silly_list);
init_waitqueue_head(&nfsi->waitqueue);
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 09e9709..dc08a6f 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -438,6 +438,7 @@
radix_tree_tag_set(&nfsi->nfs_page_tree,
req->wb_index,
NFS_PAGE_TAG_COMMIT);
+ nfsi->ncommit++;
spin_unlock(&inode->i_lock);
inc_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
inc_bdi_stat(req->wb_page->mapping->backing_dev_info, BDI_RECLAIMABLE);
@@ -573,11 +574,15 @@
nfs_scan_commit(struct inode *inode, struct list_head *dst, pgoff_t idx_start, unsigned int npages)
{
struct nfs_inode *nfsi = NFS_I(inode);
+ int ret;
if (!nfs_need_commit(nfsi))
return 0;
- return nfs_scan_list(nfsi, dst, idx_start, npages, NFS_PAGE_TAG_COMMIT);
+ ret = nfs_scan_list(nfsi, dst, idx_start, npages, NFS_PAGE_TAG_COMMIT);
+ if (ret > 0)
+ nfsi->ncommit -= ret;
+ return ret;
}
#else
static inline int nfs_need_commit(struct nfs_inode *nfsi)
@@ -642,9 +647,10 @@
spin_lock(&inode->i_lock);
}
- if (nfs_clear_request_commit(req))
- radix_tree_tag_clear(&NFS_I(inode)->nfs_page_tree,
- req->wb_index, NFS_PAGE_TAG_COMMIT);
+ if (nfs_clear_request_commit(req) &&
+ radix_tree_tag_clear(&NFS_I(inode)->nfs_page_tree,
+ req->wb_index, NFS_PAGE_TAG_COMMIT) != NULL)
+ NFS_I(inode)->ncommit--;
/* Okay, the request matches. Update the region */
if (offset < req->wb_offset) {