f2fs: add a new function to support for merging contiguous read

For better read performance, we add a new function to support for merging
contiguous read as the one for write.

v1-->v2:
 o add declarations here as Gu Zheng suggested.
 o use new structure f2fs_bio_info introduced by Jaegeuk Kim.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Acked-by: Gu Zheng <guz.fnst@cn.fujitsu.com>

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 2e54522a8061eba36fa4ae72849818589f9664fc..ce3cbd92585e73d68c66177221c7f565bb1b03b8 100644 (file)
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -414,6 +414,56 @@ int f2fs_readpage(struct f2fs_sb_info *sbi, struct page *page,
        return 0;
 }
 
+void f2fs_submit_read_bio(struct f2fs_sb_info *sbi, int rw)
+{
+       struct f2fs_bio_info *io = &sbi->read_io;
+
+       if (!io->bio)
+               return;
+
+       mutex_lock(&io->io_mutex);
+       if (io->bio) {
+               submit_bio(rw, io->bio);
+               io->bio = NULL;
+       }
+       mutex_unlock(&io->io_mutex);
+}
+
+void submit_read_page(struct f2fs_sb_info *sbi, struct page *page,
+                                       block_t blk_addr, int rw)
+{
+       struct block_device *bdev = sbi->sb->s_bdev;
+       struct f2fs_bio_info *io = &sbi->read_io;
+       int bio_blocks;
+
+       verify_block_addr(sbi, blk_addr);
+
+       mutex_lock(&io->io_mutex);
+
+       if (io->bio && io->last_block_in_bio != blk_addr - 1) {
+               submit_bio(rw, io->bio);
+               io->bio = NULL;
+       }
+alloc_new:
+       if (io->bio == NULL) {
+               bio_blocks = MAX_BIO_BLOCKS(max_hw_blocks(sbi));
+               io->bio = f2fs_bio_alloc(bdev, bio_blocks);
+               io->bio->bi_sector = SECTOR_FROM_BLOCK(sbi, blk_addr);
+               io->bio->bi_end_io = read_end_io;
+       }
+
+       if (bio_add_page(io->bio, page, PAGE_CACHE_SIZE, 0) <
+                                                       PAGE_CACHE_SIZE) {
+               submit_bio(rw, io->bio);
+               io->bio = NULL;
+               goto alloc_new;
+       }
+
+       io->last_block_in_bio = blk_addr;
+
+       mutex_unlock(&io->io_mutex);
+}
+
 /*
  * This function should be used by the data read flow only where it
  * does not check the "create" flag that indicates block allocation.

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index b665ce492e1fd2eb9497884549c2e9295739cbe9..72718ef0d56aaa19c64a93390ddc7fa5983fb831 100644 (file)
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -382,6 +382,7 @@ struct f2fs_sb_info {
        struct f2fs_sm_info *sm_info;           /* segment manager */
 
        /* for bio operations */
+       struct f2fs_bio_info read_io;                   /* for read bios */
        struct f2fs_bio_info write_io[NR_PAGE_TYPE];    /* for write bios */
 
        /* for checkpoint */
@@ -1132,6 +1133,8 @@ struct page *find_data_page(struct inode *, pgoff_t, bool);
 struct page *get_lock_data_page(struct inode *, pgoff_t);
 struct page *get_new_data_page(struct inode *, struct page *, pgoff_t, bool);
 int f2fs_readpage(struct f2fs_sb_info *, struct page *, block_t, int);
+void f2fs_submit_read_bio(struct f2fs_sb_info *, int);
+void submit_read_page(struct f2fs_sb_info *, struct page *, block_t, int);
 int do_write_data_page(struct page *);
 
 /*

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 8c677e958deb4793113349bcba79734199d507f0..9981b28744edcd593730894831ceef4c0483c150 100644 (file)
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -878,6 +878,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
        sbi->por_doing = false;
        spin_lock_init(&sbi->stat_lock);
 
+       mutex_init(&sbi->read_io.io_mutex);
        for (i = 0; i < NR_PAGE_TYPE; i++)
                mutex_init(&sbi->write_io[i].io_mutex);