f2fs: readahead contiguous pages for restore_node_summary
If cp has no CP_UMOUNT_FLAG, we will read all pages in whole node segment
one by one, it makes low performance. So let's merge contiguous pages and
readahead for better performance.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
[Jaegeuk Kim: adjust the new bio operations]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 0e1a3df..0855168 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1565,47 +1565,84 @@
return 0;
}
+/*
+ * ra_sum_pages() merge contiguous pages into one bio and submit.
+ * these pre-readed pages are linked in pages list.
+ */
+static int ra_sum_pages(struct f2fs_sb_info *sbi, struct list_head *pages,
+ int start, int nrpages)
+{
+ struct page *page;
+ int page_idx = start;
+
+ for (; page_idx < start + nrpages; page_idx++) {
+ /* alloc temporal page for read node summary info*/
+ page = alloc_page(GFP_NOFS | __GFP_ZERO);
+ if (!page) {
+ struct page *tmp;
+ list_for_each_entry_safe(page, tmp, pages, lru) {
+ list_del(&page->lru);
+ unlock_page(page);
+ __free_pages(page, 0);
+ }
+ return -ENOMEM;
+ }
+
+ lock_page(page);
+ page->index = page_idx;
+ list_add_tail(&page->lru, pages);
+ }
+
+ list_for_each_entry(page, pages, lru)
+ f2fs_submit_page_mbio(sbi, page, page->index, META, READ);
+
+ f2fs_submit_merged_bio(sbi, META, true, READ);
+ return 0;
+}
+
int restore_node_summary(struct f2fs_sb_info *sbi,
unsigned int segno, struct f2fs_summary_block *sum)
{
struct f2fs_node *rn;
struct f2fs_summary *sum_entry;
- struct page *page;
+ struct page *page, *tmp;
block_t addr;
- int i, last_offset;
-
- /* alloc temporal page for read node */
- page = alloc_page(GFP_NOFS | __GFP_ZERO);
- if (!page)
- return -ENOMEM;
- lock_page(page);
+ int bio_blocks = MAX_BIO_BLOCKS(max_hw_blocks(sbi));
+ int i, last_offset, nrpages, err = 0;
+ LIST_HEAD(page_list);
/* scan the node segment */
last_offset = sbi->blocks_per_seg;
addr = START_BLOCK(sbi, segno);
sum_entry = &sum->entries[0];
- for (i = 0; i < last_offset; i++, sum_entry++) {
- /*
- * In order to read next node page,
- * we must clear PageUptodate flag.
- */
- ClearPageUptodate(page);
+ for (i = 0; i < last_offset; i += nrpages, addr += nrpages) {
+ nrpages = min(last_offset - i, bio_blocks);
- if (f2fs_submit_page_bio(sbi, page, addr, READ_SYNC))
- goto out;
+ /* read ahead node pages */
+ err = ra_sum_pages(sbi, &page_list, addr, nrpages);
+ if (err)
+ return err;
- lock_page(page);
- rn = F2FS_NODE(page);
- sum_entry->nid = rn->footer.nid;
- sum_entry->version = 0;
- sum_entry->ofs_in_node = 0;
- addr++;
+ list_for_each_entry_safe(page, tmp, &page_list, lru) {
+
+ lock_page(page);
+ if(PageUptodate(page)) {
+ rn = F2FS_NODE(page);
+ sum_entry->nid = rn->footer.nid;
+ sum_entry->version = 0;
+ sum_entry->ofs_in_node = 0;
+ sum_entry++;
+ } else {
+ err = -EIO;
+ }
+
+ list_del(&page->lru);
+ unlock_page(page);
+ __free_pages(page, 0);
+ }
}
- unlock_page(page);
-out:
- __free_pages(page, 0);
- return 0;
+ return err;
}
static bool flush_nats_in_journal(struct f2fs_sb_info *sbi)
