f2fs: reduce stack memory cost by using bitfield in struct f2fs_io_info

This patch tries to use bitfield in struct f2fs_io_info to improve
memory usage.

struct f2fs_io_info {
...
	unsigned int need_lock:8;	/* indicate we need to lock cp_rwsem */
	unsigned int version:8;		/* version of the node */
	unsigned int submitted:1;	/* indicate IO submission */
	unsigned int in_list:1;		/* indicate fio is in io_list */
	unsigned int is_por:1;		/* indicate IO is from recovery or not */
	unsigned int retry:1;		/* need to reallocate block address */
	unsigned int encrypted:1;	/* indicate file is encrypted */
	unsigned int post_read:1;	/* require post read */
...
};

After this patch, size of struct f2fs_io_info reduces from 136 to 120.

[Nathan: fix a compile warning (single-bit-bitfield-constant-conversion)]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c
index 7e2b44d..89ce08b 100644 (file)
--- a/fs/f2fs/checkpoint.c
+++ b/fs/f2fs/checkpoint.c
@@ -70,7 +70,7 @@ static struct page *__get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index,
                .old_blkaddr = index,
                .new_blkaddr = index,
                .encrypted_page = NULL,
-               .is_por = !is_meta,
+               .is_por = !is_meta ? 1 : 0,
        };
        int err;
 
@@ -237,8 +237,8 @@ int f2fs_ra_meta_pages(struct f2fs_sb_info *sbi, block_t start, int nrpages,
                .op = REQ_OP_READ,
                .op_flags = sync ? (REQ_META | REQ_PRIO) : REQ_RAHEAD,
                .encrypted_page = NULL,
-               .in_list = false,
-               .is_por = (type == META_POR),
+               .in_list = 0,
+               .is_por = (type == META_POR) ? 1 : 0,
        };
        struct blk_plug plug;
        int err;

diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
index b196b88..a469cdd 100644 (file)
--- a/fs/f2fs/compress.c
+++ b/fs/f2fs/compress.c
@@ -1213,10 +1213,11 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,
                .page = NULL,
                .encrypted_page = NULL,
                .compressed_page = NULL,
-               .submitted = false,
+               .submitted = 0,
                .io_type = io_type,
                .io_wbc = wbc,
-               .encrypted = fscrypt_inode_uses_fs_layer_crypto(cc->inode),
+               .encrypted = fscrypt_inode_uses_fs_layer_crypto(cc->inode) ?
+                                                                       1 : 0,
        };
        struct dnode_of_data dn;
        struct node_info ni;

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index c940da1..754841b 100644 (file)
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -992,7 +992,7 @@ next:
                bio_page = fio->page;
 
        /* set submitted = true as a return value */
-       fio->submitted = true;
+       fio->submitted = 1;
 
        inc_page_count(sbi, WB_DATA_TYPE(bio_page));
 
@@ -1008,7 +1008,7 @@ alloc_new:
                                (fio->type == DATA || fio->type == NODE) &&
                                fio->new_blkaddr & F2FS_IO_SIZE_MASK(sbi)) {
                        dec_page_count(sbi, WB_DATA_TYPE(bio_page));
-                       fio->retry = true;
+                       fio->retry = 1;
                        goto skip;
                }
                io->bio = __bio_alloc(fio, BIO_MAX_VECS);
@@ -2776,10 +2776,10 @@ int f2fs_write_single_data_page(struct page *page, int *submitted,
                .old_blkaddr = NULL_ADDR,
                .page = page,
                .encrypted_page = NULL,
-               .submitted = false,
+               .submitted = 0,
                .compr_blocks = compr_blocks,
                .need_lock = LOCK_RETRY,
-               .post_read = f2fs_post_read_required(inode),
+               .post_read = f2fs_post_read_required(inode) ? 1 : 0,
                .io_type = io_type,
                .io_wbc = wbc,
                .bio = bio,
@@ -2900,7 +2900,7 @@ out:
        }
 
        if (submitted)
-               *submitted = fio.submitted ? 1 : 0;
+               *submitted = fio.submitted;
 
        return 0;
 

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index f3c5f77..5449c82 100644 (file)
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1210,19 +1210,19 @@ struct f2fs_io_info {
        struct page *encrypted_page;    /* encrypted page */
        struct page *compressed_page;   /* compressed page */
        struct list_head list;          /* serialize IOs */
-       bool submitted;         /* indicate IO submission */
-       int need_lock;          /* indicate we need to lock cp_rwsem */
-       bool in_list;           /* indicate fio is in io_list */
-       bool is_por;            /* indicate IO is from recovery or not */
-       bool retry;             /* need to reallocate block address */
-       int compr_blocks;       /* # of compressed block addresses */
-       bool encrypted;         /* indicate file is encrypted */
-       bool post_read;         /* require post read */
+       unsigned int compr_blocks;      /* # of compressed block addresses */
+       unsigned int need_lock:8;       /* indicate we need to lock cp_rwsem */
+       unsigned int version:8;         /* version of the node */
+       unsigned int submitted:1;       /* indicate IO submission */
+       unsigned int in_list:1;         /* indicate fio is in io_list */
+       unsigned int is_por:1;          /* indicate IO is from recovery or not */
+       unsigned int retry:1;           /* need to reallocate block address */
+       unsigned int encrypted:1;       /* indicate file is encrypted */
+       unsigned int post_read:1;       /* require post read */
        enum iostat_type io_type;       /* io type */
        struct writeback_control *io_wbc; /* writeback control */
        struct bio **bio;               /* bio for ipu */
        sector_t *last_block;           /* last block number in bio */
-       unsigned char version;          /* version of the node */
 };
 
 struct bio_entry {

diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index 97e8462..0a9dfa4 100644 (file)
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -1156,8 +1156,8 @@ static int ra_data_block(struct inode *inode, pgoff_t index)
                .op = REQ_OP_READ,
                .op_flags = 0,
                .encrypted_page = NULL,
-               .in_list = false,
-               .retry = false,
+               .in_list = 0,
+               .retry = 0,
        };
        int err;
 
@@ -1245,8 +1245,8 @@ static int move_data_block(struct inode *inode, block_t bidx,
                .op = REQ_OP_READ,
                .op_flags = 0,
                .encrypted_page = NULL,
-               .in_list = false,
-               .retry = false,
+               .in_list = 0,
+               .retry = 0,
        };
        struct dnode_of_data dn;
        struct f2fs_summary sum;

diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index fbd1d25..19a1fee 100644 (file)
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1586,7 +1586,7 @@ static int __write_node_page(struct page *page, bool atomic, bool *submitted,
                .op_flags = wbc_to_write_flags(wbc),
                .page = page,
                .encrypted_page = NULL,
-               .submitted = false,
+               .submitted = 0,
                .io_type = io_type,
                .io_wbc = wbc,
        };

diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
index f46a8c0..69b01b5 100644 (file)
--- a/fs/f2fs/segment.c
+++ b/fs/f2fs/segment.c
@@ -3314,10 +3314,10 @@ void f2fs_allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
                struct f2fs_bio_info *io;
 
                if (F2FS_IO_ALIGNED(sbi))
-                       fio->retry = false;
+                       fio->retry = 0;
 
                INIT_LIST_HEAD(&fio->list);
-               fio->in_list = true;
+               fio->in_list = 1;
                io = sbi->write_io[fio->type] + fio->temp;
                spin_lock(&io->io_lock);
                list_add_tail(&fio->list, &io->io_list);
@@ -3398,7 +3398,7 @@ void f2fs_do_write_meta_page(struct f2fs_sb_info *sbi, struct page *page,
                .new_blkaddr = page->index,
                .page = page,
                .encrypted_page = NULL,
-               .in_list = false,
+               .in_list = 0,
        };
 
        if (unlikely(page->index >= MAIN_BLKADDR(sbi)))