Commit fe55d563 authored by NeilBrown's avatar NeilBrown Committed by Linus Torvalds
Browse files

remove inode_congested() 

inode_congested() reports if the backing-device for the inode is
congested.  No bdi reports congestion any more, so this always returns
'false'.

So remove inode_congested() and related functions, and remove the call
sites, assuming that inode_congested() always returns 'false'.

Link: https://lkml.kernel.org/r/164549983741.9187.2174285592262191311.stgit@noble.brown


Signed-off-by: default avatarNeilBrown <neilb@suse.de>
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Paolo Valente <paolo.valente@linaro.org>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 503d4fa6

fs/fs-writeback.c

+0 −37
Original line number Diff line number Diff line
@@ -893,43 +893,6 @@ void wbc_account_cgroup_owner(struct writeback_control *wbc, struct page *page, 
}

EXPORT_SYMBOL_GPL(wbc_account_cgroup_owner);



/**

 * inode_congested - test whether an inode is congested

 * @inode: inode to test for congestion (may be NULL)

 * @cong_bits: mask of WB_[a]sync_congested bits to test

 *

 * Tests whether @inode is congested.  @cong_bits is the mask of congestion

 * bits to test and the return value is the mask of set bits.

 *

 * If cgroup writeback is enabled for @inode, the congestion state is

 * determined by whether the cgwb (cgroup bdi_writeback) for the blkcg

 * associated with @inode is congested; otherwise, the root wb's congestion

 * state is used.

 *

 * @inode is allowed to be NULL as this function is often called on

 * mapping->host which is NULL for the swapper space.

 */

int inode_congested(struct inode *inode, int cong_bits)

{

	/*

	 * Once set, ->i_wb never becomes NULL while the inode is alive.

	 * Start transaction iff ->i_wb is visible.

	 */

	if (inode && inode_to_wb_is_valid(inode)) {

		struct bdi_writeback *wb;

		struct wb_lock_cookie lock_cookie = {};

		bool congested;



		wb = unlocked_inode_to_wb_begin(inode, &lock_cookie);

		congested = wb_congested(wb, cong_bits);

		unlocked_inode_to_wb_end(inode, &lock_cookie);

		return congested;

	}



	return wb_congested(&inode_to_bdi(inode)->wb, cong_bits);

}

EXPORT_SYMBOL_GPL(inode_congested);



/**

 * wb_split_bdi_pages - split nr_pages to write according to bandwidth

 * @wb: target bdi_writeback to split @nr_pages to

include/linux/backing-dev.h

+0 −22
Original line number Diff line number Diff line
@@ -162,7 +162,6 @@ struct bdi_writeback *wb_get_create(struct backing_dev_info *bdi, 
				    gfp_t gfp);

void wb_memcg_offline(struct mem_cgroup *memcg);

void wb_blkcg_offline(struct blkcg *blkcg);

int inode_congested(struct inode *inode, int cong_bits);



/**

 * inode_cgwb_enabled - test whether cgroup writeback is enabled on an inode
@@ -390,29 +389,8 @@ static inline void wb_blkcg_offline(struct blkcg *blkcg) 
{

}



static inline int inode_congested(struct inode *inode, int cong_bits)

{

	return wb_congested(&inode_to_bdi(inode)->wb, cong_bits);

}



#endif	/* CONFIG_CGROUP_WRITEBACK */



static inline int inode_read_congested(struct inode *inode)

{

	return inode_congested(inode, 1 << WB_sync_congested);

}



static inline int inode_write_congested(struct inode *inode)

{

	return inode_congested(inode, 1 << WB_async_congested);

}



static inline int inode_rw_congested(struct inode *inode)

{

	return inode_congested(inode, (1 << WB_sync_congested) |

				      (1 << WB_async_congested));

}



static inline int bdi_congested(struct backing_dev_info *bdi, int cong_bits)

{

	return wb_congested(&bdi->wb, cong_bits);

mm/fadvise.c

+2 −3
Original line number Diff line number Diff line
@@ -109,7 +109,6 @@ int generic_fadvise(struct file *file, loff_t offset, loff_t len, int advice) 
	case POSIX_FADV_NOREUSE:

		break;

	case POSIX_FADV_DONTNEED:

		if (!inode_write_congested(mapping->host))

		__filemap_fdatawrite_range(mapping, offset, endbyte,

					   WB_SYNC_NONE);

mm/readahead.c

+0 −6
Original line number Diff line number Diff line
@@ -709,12 +709,6 @@ void page_cache_async_ra(struct readahead_control *ractl, 


	folio_clear_readahead(folio);



	/*

	 * Defer asynchronous read-ahead on IO congestion.

	 */

	if (inode_read_congested(ractl->mapping->host))

		return;



	if (blk_cgroup_congested())

		return;

mm/vmscan.c

+1 −16
Original line number Diff line number Diff line
@@ -989,17 +989,6 @@ static inline int is_page_cache_freeable(struct page *page) 
	return page_count(page) - page_has_private(page) == 1 + page_cache_pins;

}



static int may_write_to_inode(struct inode *inode)

{

	if (current->flags & PF_SWAPWRITE)

		return 1;

	if (!inode_write_congested(inode))

		return 1;

	if (inode_to_bdi(inode) == current->backing_dev_info)

		return 1;

	return 0;

}



/*

 * We detected a synchronous write error writing a page out.  Probably

 * -ENOSPC.  We need to propagate that into the address_space for a subsequent
@@ -1201,8 +1190,6 @@ static pageout_t pageout(struct page *page, struct address_space *mapping) 
	}

	if (mapping->a_ops->writepage == NULL)

		return PAGE_ACTIVATE;

	if (!may_write_to_inode(mapping->host))

		return PAGE_KEEP;



	if (clear_page_dirty_for_io(page)) {

		int res;
@@ -1578,9 +1565,7 @@ static unsigned int shrink_page_list(struct list_head *page_list, 
		 * end of the LRU a second time.

		 */

		mapping = page_mapping(page);

		if (((dirty || writeback) && mapping &&

		     inode_write_congested(mapping->host)) ||

		    (writeback && PageReclaim(page)))

		if (writeback && PageReclaim(page))

			stat->nr_congested++;



		/*