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>

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>
Trond Myklebust
1 parent 9fd367f0f3
Showing 3 changed files with 15 additions and 10 deletions Side-by-side Diff
fs/nfs/pagelist.c
fs/nfs/write.c
include/linux/nfs_page.h
@@ -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++;
 			}
@@ -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");
@@ -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),
...	...	@@ -381,10 +381,10 @@
381	381	/**
382	382	* nfs_scan_list - Scan a list for matching requests
383	383	* @nfsi: NFS inode
384		- * @head: One of the NFS inode request lists
385	384	* @dst: Destination list
386	385	* @idx_start: lower bound of page->index to scan
387	386	* @npages: idx_start + npages sets the upper bound to scan.
	387	+ * @tag: tag to scan for
388	388	*
389	389	* Moves elements from one of the inode request lists.
390	390	* If the number of requests is set to 0, the entire address_space
391	391
...	...	@@ -392,9 +392,9 @@
392	392	* The requests are not checked to ensure that they form a contiguous set.
393	393	* You must be holding the inode's req_lock when calling this function
394	394	*/
395		-int nfs_scan_list(struct nfs_inode nfsi, struct list_head head,
	395	+int nfs_scan_list(struct nfs_inode *nfsi,
396	396	struct list_head *dst, pgoff_t idx_start,
397		- unsigned int npages)
	397	+ unsigned int npages, int tag)
398	398	{
399	399	struct nfs_page *pgvec[NFS_SCAN_MAXENTRIES];
400	400	struct nfs_page *req;
401	401
...	...	@@ -409,9 +409,9 @@
409	409	idx_end = idx_start + npages - 1;
410	410
411	411	for (;;) {
412		- found = radix_tree_gang_lookup(&nfsi->nfs_page_tree,
	412	+ found = radix_tree_gang_lookup_tag(&nfsi->nfs_page_tree,
413	413	(void **)&pgvec[0], idx_start,
414		- NFS_SCAN_MAXENTRIES);
	414	+ NFS_SCAN_MAXENTRIES, tag);
415	415	if (found <= 0)
416	416	break;
417	417	for (i = 0; i < found; i++) {
418	418
...	...	@@ -419,10 +419,10 @@
419	419	if (req->wb_index > idx_end)
420	420	goto out;
421	421	idx_start = req->wb_index + 1;
422		- if (req->wb_list_head != head)
423		- continue;
424	422	if (nfs_set_page_tag_locked(req)) {
425	423	nfs_list_remove_request(req);
	424	+ radix_tree_tag_clear(&nfsi->nfs_page_tree,
	425	+ req->wb_index, tag);
426	426	nfs_list_add_request(req, dst);
427	427	res++;
428	428	}
...	...	@@ -462,6 +462,9 @@
462	462	nfs_list_add_request(req, &nfsi->commit);
463	463	nfsi->ncommit++;
464	464	set_bit(PG_NEED_COMMIT, &(req)->wb_flags);
	465	+ radix_tree_tag_set(&nfsi->nfs_page_tree,
	466	+ req->wb_index,
	467	+ NFS_PAGE_TAG_COMMIT);
465	468	spin_unlock(&nfsi->req_lock);
466	469	inc_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
467	470	__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
...	...	@@ -575,7 +578,8 @@
575	578	int res = 0;
576	579
577	580	if (nfsi->ncommit != 0) {
578		- res = nfs_scan_list(nfsi, &nfsi->commit, dst, idx_start, npages);
	581	+ res = nfs_scan_list(nfsi, dst, idx_start, npages,
	582	+ NFS_PAGE_TAG_COMMIT);
579	583	nfsi->ncommit -= res;
580	584	if ((nfsi->ncommit == 0) != list_empty(&nfsi->commit))
581	585	printk(KERN_ERR "NFS: desynchronized value of nfs_i.ncommit.\n");
...	...	@@ -22,6 +22,7 @@
22	22	* Valid flags for the radix tree
23	23	*/
24	24	#define NFS_PAGE_TAG_LOCKED 0
	25	+#define NFS_PAGE_TAG_COMMIT 1
25	26
26	27	/*
27	28	* Valid flags for a dirty buffer
...	...	@@ -71,8 +72,8 @@
71	72	extern void nfs_release_request(struct nfs_page *req);
72	73
73	74
74		-extern int nfs_scan_list(struct nfs_inode nfsi, struct list_head head, struct list_head *dst,
75		- pgoff_t idx_start, unsigned int npages);
	75	+extern int nfs_scan_list(struct nfs_inode nfsi, struct list_head dst,
	76	+ pgoff_t idx_start, unsigned int npages, int tag);
76	77	extern void nfs_pageio_init(struct nfs_pageio_descriptor *desc,
77	78	struct inode *inode,
78	79	int (doio)(struct inode , struct list_head *, unsigned int, size_t, int),