On 21.12.18 15:40, Nikolay Borisov wrote:
> All users of VM_MAX_READAHEAD actually convert it to kbytes and then to
> pages. Define the macro explicitly as (SZ_128K / PAGE_SIZE). This
> simplifies the expression in every filesystem. Also rename the macro to
> VM_READAHEAD_PAGES to properly convey its meaning. Finally remove unused
> VM_MIN_READAHEAD
>
> Signed-off-by: Nikolay Borisov <nborisov@xxxxxxxx>
> ---
> block/blk-core.c | 3 +--
> fs/9p/vfs_super.c | 2 +-
> fs/afs/super.c | 2 +-
> fs/btrfs/disk-io.c | 2 +-
> fs/fuse/inode.c | 2 +-
> include/linux/mm.h | 4 ++--
> 6 files changed, 7 insertions(+), 8 deletions(-)
>
> diff --git a/block/blk-core.c b/block/blk-core.c
> index deb56932f8c4..d25c8564a117 100644
> --- a/block/blk-core.c
> +++ b/block/blk-core.c
> @@ -1031,8 +1031,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id,
> if (!q->stats)
> goto fail_stats;
>
> - q->backing_dev_info->ra_pages =
> - (VM_MAX_READAHEAD * 1024) / PAGE_SIZE;
> + q->backing_dev_info->ra_pages = VM_READAHEAD_PAGES;
> q->backing_dev_info->capabilities = BDI_CAP_CGROUP_WRITEBACK;
> q->backing_dev_info->name = "block";
> q->node = node_id;
> diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
> index 48ce50484e80..10d3bd3f534b 100644
> --- a/fs/9p/vfs_super.c
> +++ b/fs/9p/vfs_super.c
> @@ -92,7 +92,7 @@ v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
> return ret;
>
> if (v9ses->cache)
> - sb->s_bdi->ra_pages = (VM_MAX_READAHEAD * 1024)/PAGE_SIZE;
> + sb->s_bdi->ra_pages = VM_READAHEAD_PAGES;
>
> sb->s_flags |= SB_ACTIVE | SB_DIRSYNC;
> if (!v9ses->cache)
> diff --git a/fs/afs/super.c b/fs/afs/super.c
> index dcd07fe99871..e684f6769b15 100644
> --- a/fs/afs/super.c
> +++ b/fs/afs/super.c
> @@ -399,7 +399,7 @@ static int afs_fill_super(struct super_block *sb,
> ret = super_setup_bdi(sb);
> if (ret)
> return ret;
> - sb->s_bdi->ra_pages = VM_MAX_READAHEAD * 1024 / PAGE_SIZE;
> + sb->s_bdi->ra_pages = VM_READAHEAD_PAGES;
>
> /* allocate the root inode and dentry */
> if (as->dyn_root) {
> diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
> index 6d776717d8b3..ee47d8b5b50c 100644
> --- a/fs/btrfs/disk-io.c
> +++ b/fs/btrfs/disk-io.c
> @@ -2900,7 +2900,7 @@ int open_ctree(struct super_block *sb,
> sb->s_bdi->congested_fn = btrfs_congested_fn;
> sb->s_bdi->congested_data = fs_info;
> sb->s_bdi->capabilities |= BDI_CAP_CGROUP_WRITEBACK;
> - sb->s_bdi->ra_pages = VM_MAX_READAHEAD * SZ_1K / PAGE_SIZE;
> + sb->s_bdi->ra_pages = VM_READAHEAD_PAGES;
> sb->s_bdi->ra_pages *= btrfs_super_num_devices(disk_super);
> sb->s_bdi->ra_pages = max(sb->s_bdi->ra_pages, SZ_4M / PAGE_SIZE);
>
> diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
> index 568abed20eb2..d3eab53a29b7 100644
> --- a/fs/fuse/inode.c
> +++ b/fs/fuse/inode.c
> @@ -1009,7 +1009,7 @@ static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
> if (err)
> return err;
>
> - sb->s_bdi->ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_SIZE;
> + sb->s_bdi->ra_pages = VM_READAHEAD_PAGES;
> /* fuse does it's own writeback accounting */
> sb->s_bdi->capabilities = BDI_CAP_NO_ACCT_WB | BDI_CAP_STRICTLIMIT;
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 5411de93a363..1579082af177 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -26,6 +26,7 @@
> #include <linux/page_ref.h>
> #include <linux/memremap.h>
> #include <linux/overflow.h>
> +#include <linux/sizes.h>
>
> struct mempolicy;
> struct anon_vma;
> @@ -2396,8 +2397,7 @@ int __must_check write_one_page(struct page *page);
> void task_dirty_inc(struct task_struct *tsk);
>
> /* readahead.c */
> -#define VM_MAX_READAHEAD 128 /* kbytes */
> -#define VM_MIN_READAHEAD 16 /* kbytes (includes current page) */
> +#define VM_READAHEAD_PAGES (SZ_128K / PAGE_SIZE)
>
> int force_page_cache_readahead(struct address_space *mapping, struct file *filp,
> pgoff_t offset, unsigned long nr_to_read);
>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
--
Thanks,
David / dhildenb
