Commit c7b23b68 authored by Yosry Ahmed's avatar Yosry Ahmed Committed by Andrew Morton
Browse files

mm: vmscan: refactor updating current->reclaim_state 

During reclaim, we keep track of pages reclaimed from other means than
LRU-based reclaim through scan_control->reclaim_state->reclaimed_slab,
which we stash a pointer to in current task_struct.

However, we keep track of more than just reclaimed slab pages through
this.  We also use it for clean file pages dropped through pruned inodes,
and xfs buffer pages freed.  Rename reclaimed_slab to reclaimed, and add a
helper function that wraps updating it through current, so that future
changes to this logic are contained within include/linux/swap.h.

Link: https://lkml.kernel.org/r/20230413104034.1086717-4-yosryahmed@google.com


Signed-off-by: default avatarYosry Ahmed <yosryahmed@google.com>
Acked-by: default avatarMichal Hocko <mhocko@suse.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Lameter <cl@linux.com>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: NeilBrown <neilb@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent ef05e689

fs/inode.c

+1 −2
Original line number Diff line number Diff line
@@ -864,8 +864,7 @@ static enum lru_status inode_lru_isolate(struct list_head *item, 
				__count_vm_events(KSWAPD_INODESTEAL, reap);

			else

				__count_vm_events(PGINODESTEAL, reap);

			if (current->reclaim_state)

				current->reclaim_state->reclaimed_slab += reap;

			mm_account_reclaimed_pages(reap);

		}

		iput(inode);

		spin_lock(lru_lock);

fs/xfs/xfs_buf.c

+1 −2
Original line number Diff line number Diff line
@@ -286,8 +286,7 @@ xfs_buf_free_pages( 
		if (bp->b_pages[i])

			__free_page(bp->b_pages[i]);

	}

	if (current->reclaim_state)

		current->reclaim_state->reclaimed_slab += bp->b_page_count;

	mm_account_reclaimed_pages(bp->b_page_count);



	if (bp->b_pages != bp->b_page_array)

		kmem_free(bp->b_pages);

include/linux/swap.h

+16 −1
Original line number Diff line number Diff line
@@ -153,13 +153,28 @@ union swap_header { 
 * memory reclaim

 */

struct reclaim_state {

	unsigned long reclaimed_slab;

	/* pages reclaimed outside of LRU-based reclaim */

	unsigned long reclaimed;

#ifdef CONFIG_LRU_GEN

	/* per-thread mm walk data */

	struct lru_gen_mm_walk *mm_walk;

#endif

};



/*

 * mm_account_reclaimed_pages(): account reclaimed pages outside of LRU-based

 * reclaim

 * @pages: number of pages reclaimed

 *

 * If the current process is undergoing a reclaim operation, increment the

 * number of reclaimed pages by @pages.

 */

static inline void mm_account_reclaimed_pages(unsigned long pages)

{

	if (current->reclaim_state)

		current->reclaim_state->reclaimed += pages;

}



#ifdef __KERNEL__



struct address_space;

mm/slab.c

+1 −2
Original line number Diff line number Diff line
@@ -1392,8 +1392,7 @@ static void kmem_freepages(struct kmem_cache *cachep, struct slab *slab) 
	smp_wmb();

	__folio_clear_slab(folio);



	if (current->reclaim_state)

		current->reclaim_state->reclaimed_slab += 1 << order;

	mm_account_reclaimed_pages(1 << order);

	unaccount_slab(slab, order, cachep);

	__free_pages(&folio->page, order);

}

mm/slob.c

+2 −4
Original line number Diff line number Diff line
@@ -61,7 +61,7 @@ 
#include <linux/slab.h>



#include <linux/mm.h>

#include <linux/swap.h> /* struct reclaim_state */

#include <linux/swap.h> /* mm_account_reclaimed_pages() */

#include <linux/cache.h>

#include <linux/init.h>

#include <linux/export.h>
@@ -211,9 +211,7 @@ static void slob_free_pages(void *b, int order) 
{

	struct page *sp = virt_to_page(b);



	if (current->reclaim_state)

		current->reclaim_state->reclaimed_slab += 1 << order;



	mm_account_reclaimed_pages(1 << order);

	mod_node_page_state(page_pgdat(sp), NR_SLAB_UNRECLAIMABLE_B,

			    -(PAGE_SIZE << order));

	__free_pages(sp, order);