Re: [PATCH] buffer: remove useless comment and WB_REASON_FREE_MORE_MEM, reason.

From: Jan Kara
Date: Tue Apr 14 2020 - 11:10:15 EST


On Mon 13-04-20 13:12:10, Zhiqiang Liu wrote:
> From: Zhiqiang Liu <liuzhiqiang26@xxxxxxxxxx>
>
> free_more_memory func has been completely removed in commit bc48f001de12
> ("buffer: eliminate the need to call free_more_memory() in __getblk_slow()")
>
> So comment and `WB_REASON_FREE_MORE_MEM` reason about free_more_memory
> are no longer needed.
>
> Signed-off-by: Zhiqiang Liu <liuzhiqiang26@xxxxxxxxxx>

Thanks. The patch looks good to me. You can add:

Reviewed-by: Jan Kara <jack@xxxxxxx>

Honza

> ---
> fs/buffer.c | 2 +-
> include/linux/backing-dev-defs.h | 1 -
> include/trace/events/writeback.h | 1 -
> 3 files changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/fs/buffer.c b/fs/buffer.c
> index b8d28370cfd7..07ab0405f3f5 100644
> --- a/fs/buffer.c
> +++ b/fs/buffer.c
> @@ -973,7 +973,7 @@ grow_dev_page(struct block_device *bdev, sector_t block,
> struct page *page;
> struct buffer_head *bh;
> sector_t end_block;
> - int ret = 0; /* Will call free_more_memory() */
> + int ret = 0;
> gfp_t gfp_mask;
>
> gfp_mask = mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS) | gfp;
> diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h
> index 4fc87dee005a..ee577a83cfe6 100644
> --- a/include/linux/backing-dev-defs.h
> +++ b/include/linux/backing-dev-defs.h
> @@ -54,7 +54,6 @@ enum wb_reason {
> WB_REASON_SYNC,
> WB_REASON_PERIODIC,
> WB_REASON_LAPTOP_TIMER,
> - WB_REASON_FREE_MORE_MEM,
> WB_REASON_FS_FREE_SPACE,
> /*
> * There is no bdi forker thread any more and works are done
> diff --git a/include/trace/events/writeback.h b/include/trace/events/writeback.h
> index d94def25e4dc..85a33bea76f1 100644
> --- a/include/trace/events/writeback.h
> +++ b/include/trace/events/writeback.h
> @@ -36,7 +36,6 @@
> EM( WB_REASON_SYNC, "sync") \
> EM( WB_REASON_PERIODIC, "periodic") \
> EM( WB_REASON_LAPTOP_TIMER, "laptop_timer") \
> - EM( WB_REASON_FREE_MORE_MEM, "free_more_memory") \
> EM( WB_REASON_FS_FREE_SPACE, "fs_free_space") \
> EMe(WB_REASON_FORKER_THREAD, "forker_thread")
>
> --
> 2.19.1
>
>
--
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR