NFS: Use an atomic_long_t to count the number of requests
Rather than forcing us to take the inode->i_lock just in order to bump
the number.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 5ab5ca2..0809355 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -434,9 +434,7 @@ nfs_destroy_unlinked_subrequests(struct nfs_page *destroy_list,
if (test_and_clear_bit(PG_INODE_REF, &subreq->wb_flags)) {
nfs_release_request(subreq);
- spin_lock(&inode->i_lock);
- NFS_I(inode)->nrequests--;
- spin_unlock(&inode->i_lock);
+ atomic_long_dec(&NFS_I(inode)->nrequests);
}
/* subreq is now totally disconnected from page group or any
@@ -567,9 +565,7 @@ nfs_lock_and_join_requests(struct page *page)
if (test_and_clear_bit(PG_REMOVE, &head->wb_flags)) {
set_bit(PG_INODE_REF, &head->wb_flags);
kref_get(&head->wb_kref);
- spin_lock(&inode->i_lock);
- NFS_I(inode)->nrequests++;
- spin_unlock(&inode->i_lock);
+ atomic_long_inc(&NFS_I(inode)->nrequests);
}
nfs_page_group_unlock(head);
@@ -755,7 +751,7 @@ static void nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
nfs_lock_request(req);
spin_lock(&inode->i_lock);
- if (!nfsi->nrequests &&
+ if (!nfs_have_writebacks(inode) &&
NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE))
inode->i_version++;
/*
@@ -767,7 +763,7 @@ static void nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
SetPagePrivate(req->wb_page);
set_page_private(req->wb_page, (unsigned long)req);
}
- nfsi->nrequests++;
+ atomic_long_inc(&nfsi->nrequests);
/* this a head request for a page group - mark it as having an
* extra reference so sub groups can follow suit.
* This flag also informs pgio layer when to bump nrequests when
@@ -786,6 +782,7 @@ static void nfs_inode_remove_request(struct nfs_page *req)
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_page *head;
+ atomic_long_dec(&nfsi->nrequests);
if (nfs_page_group_sync_on_bit(req, PG_REMOVE)) {
head = req->wb_head;
@@ -795,11 +792,6 @@ static void nfs_inode_remove_request(struct nfs_page *req)
ClearPagePrivate(head->wb_page);
clear_bit(PG_MAPPED, &head->wb_flags);
}
- nfsi->nrequests--;
- spin_unlock(&inode->i_lock);
- } else {
- spin_lock(&inode->i_lock);
- nfsi->nrequests--;
spin_unlock(&inode->i_lock);
}