NFS cleanup: speed up nfs_scan_commit using radix tree tags
Add a tag for requests that are waiting for a COMMIT
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 23e9dea..ad90cbe 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -381,10 +381,10 @@
/**
* nfs_scan_list - Scan a list for matching requests
* @nfsi: NFS inode
- * @head: One of the NFS inode request lists
* @dst: Destination list
* @idx_start: lower bound of page->index to scan
* @npages: idx_start + npages sets the upper bound to scan.
+ * @tag: tag to scan for
*
* Moves elements from one of the inode request lists.
* If the number of requests is set to 0, the entire address_space
@@ -392,9 +392,9 @@
* The requests are *not* checked to ensure that they form a contiguous set.
* You must be holding the inode's req_lock when calling this function
*/
-int nfs_scan_list(struct nfs_inode *nfsi, struct list_head *head,
+int nfs_scan_list(struct nfs_inode *nfsi,
struct list_head *dst, pgoff_t idx_start,
- unsigned int npages)
+ unsigned int npages, int tag)
{
struct nfs_page *pgvec[NFS_SCAN_MAXENTRIES];
struct nfs_page *req;
@@ -409,9 +409,9 @@
idx_end = idx_start + npages - 1;
for (;;) {
- found = radix_tree_gang_lookup(&nfsi->nfs_page_tree,
+ found = radix_tree_gang_lookup_tag(&nfsi->nfs_page_tree,
(void **)&pgvec[0], idx_start,
- NFS_SCAN_MAXENTRIES);
+ NFS_SCAN_MAXENTRIES, tag);
if (found <= 0)
break;
for (i = 0; i < found; i++) {
@@ -419,10 +419,10 @@
if (req->wb_index > idx_end)
goto out;
idx_start = req->wb_index + 1;
- if (req->wb_list_head != head)
- continue;
if (nfs_set_page_tag_locked(req)) {
nfs_list_remove_request(req);
+ radix_tree_tag_clear(&nfsi->nfs_page_tree,
+ req->wb_index, tag);
nfs_list_add_request(req, dst);
res++;
}
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 754066c..0f779ca 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -462,6 +462,9 @@
nfs_list_add_request(req, &nfsi->commit);
nfsi->ncommit++;
set_bit(PG_NEED_COMMIT, &(req)->wb_flags);
+ radix_tree_tag_set(&nfsi->nfs_page_tree,
+ req->wb_index,
+ NFS_PAGE_TAG_COMMIT);
spin_unlock(&nfsi->req_lock);
inc_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
@@ -575,7 +578,8 @@
int res = 0;
if (nfsi->ncommit != 0) {
- res = nfs_scan_list(nfsi, &nfsi->commit, dst, idx_start, npages);
+ res = nfs_scan_list(nfsi, dst, idx_start, npages,
+ NFS_PAGE_TAG_COMMIT);
nfsi->ncommit -= res;
if ((nfsi->ncommit == 0) != list_empty(&nfsi->commit))
printk(KERN_ERR "NFS: desynchronized value of nfs_i.ncommit.\n");
diff --git a/include/linux/nfs_page.h b/include/linux/nfs_page.h
index 042434c..481a421 100644
--- a/include/linux/nfs_page.h
+++ b/include/linux/nfs_page.h
@@ -22,6 +22,7 @@
* Valid flags for the radix tree
*/
#define NFS_PAGE_TAG_LOCKED 0
+#define NFS_PAGE_TAG_COMMIT 1
/*
* Valid flags for a dirty buffer
@@ -71,8 +72,8 @@
extern void nfs_release_request(struct nfs_page *req);
-extern int nfs_scan_list(struct nfs_inode *nfsi, struct list_head *head, struct list_head *dst,
- pgoff_t idx_start, unsigned int npages);
+extern int nfs_scan_list(struct nfs_inode *nfsi, struct list_head *dst,
+ pgoff_t idx_start, unsigned int npages, int tag);
extern void nfs_pageio_init(struct nfs_pageio_descriptor *desc,
struct inode *inode,
int (*doio)(struct inode *, struct list_head *, unsigned int, size_t, int),