iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

mm: generalize putback scan functions

Browse Source 
This combines two similar functions move_active_pages_to_lru() and
putback_inactive_pages() into single move_pages_to_lru().  This remove
duplicate code and makes object file size smaller.

Before:
   text	   data	    bss	    dec	    hex	filename
  57082	   4732	    128	  61942	   f1f6	mm/vmscan.o
After:
   text	   data	    bss	    dec	    hex	filename
  55112	   4600	    128	  59840	   e9c0	mm/vmscan.o

Note, that now we are checking for !page_evictable() coming from
shrink_active_list(), which shouldn't change any behavior since that path
works with evictable pages only.

Link: http://lkml.kernel.org/r/155290129627.31489.8321971028677203248.stgit@localhost.localdomain
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Kirill Tkhai 2019-05-13 17:17:00 -07:00 committed by Linus Torvalds
parent f372d89e5d
commit a222f34158
1 changed files with 40 additions and 82 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

122
mm/vmscan.c
View File

@ -1807,33 +1807,53 @@ static int too_many_isolated(struct pglist_data *pgdat, int file,
return isolated > inactive;
}
static noinline_for_stack void
putback_inactive_pages(struct lruvec *lruvec, struct list_head *page_list)
/*
* This moves pages from @list to corresponding LRU list.
*
* We move them the other way if the page is referenced by one or more
* processes, from rmap.
*
* If the pages are mostly unmapped, the processing is fast and it is
* appropriate to hold zone_lru_lock across the whole operation. But if
* the pages are mapped, the processing is slow (page_referenced()) so we
* should drop zone_lru_lock around each page. It's impossible to balance
* this, so instead we remove the pages from the LRU while processing them.
* It is safe to rely on PG_active against the non-LRU pages in here because
* nobody will play with that bit on a non-LRU page.
*
* The downside is that we have to touch page->_refcount against each page.
* But we had to alter page->flags anyway.
*
* Returns the number of pages moved to the given lruvec.
*/
static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec,
struct list_head *list)
{
struct pglist_data *pgdat = lruvec_pgdat(lruvec);
int nr_pages, nr_moved = 0;
LIST_HEAD(pages_to_free);
struct page *page;
enum lru_list lru;
/*
* Put back any unfreeable pages.
*/
while (!list_empty(page_list)) {
struct page *page = lru_to_page(page_list);
int lru;
while (!list_empty(list)) {
page = lru_to_page(list);
VM_BUG_ON_PAGE(PageLRU(page), page);
list_del(&page->lru);
if (unlikely(!page_evictable(page))) {
list_del(&page->lru);
spin_unlock_irq(&pgdat->lru_lock);
putback_lru_page(page);
spin_lock_irq(&pgdat->lru_lock);
continue;
}
lruvec = mem_cgroup_page_lruvec(page, pgdat);
SetPageLRU(page);
lru = page_lru(page);
add_page_to_lru_list(page, lruvec, lru);
nr_pages = hpage_nr_pages(page);
update_lru_size(lruvec, lru, page_zonenum(page), nr_pages);
list_move(&page->lru, &lruvec->lists[lru]);
if (put_page_testzero(page)) {
__ClearPageLRU(page);
@ -1847,13 +1867,17 @@ putback_inactive_pages(struct lruvec *lruvec, struct list_head *page_list)
spin_lock_irq(&pgdat->lru_lock);
} else
list_add(&page->lru, &pages_to_free);
} else {
nr_moved += nr_pages;
}
}
/*
* To save our caller's stack, now use input list for pages to free.
*/
list_splice(&pages_to_free, page_list);
list_splice(&pages_to_free, list);
return nr_moved;
}
/*
@ -1945,7 +1969,7 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
reclaim_stat->recent_rotated[0] = stat.nr_activate[0];
reclaim_stat->recent_rotated[1] = stat.nr_activate[1];
putback_inactive_pages(lruvec, &page_list);
move_pages_to_lru(lruvec, &page_list);
__mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, -nr_taken);
@ -1982,72 +2006,6 @@ shrink_inactive_list(unsigned long nr_to_scan, struct lruvec *lruvec,
return nr_reclaimed;
}
/*
* This moves pages from the active list to the inactive list.
*
* We move them the other way if the page is referenced by one or more
* processes, from rmap.
*
* If the pages are mostly unmapped, the processing is fast and it is
* appropriate to hold pgdat->lru_lock across the whole operation. But if
* the pages are mapped, the processing is slow (page_referenced()) so we
* should drop pgdat->lru_lock around each page. It's impossible to balance
* this, so instead we remove the pages from the LRU while processing them.
* It is safe to rely on PG_active against the non-LRU pages in here because
* nobody will play with that bit on a non-LRU page.
*
* The downside is that we have to touch page->_refcount against each page.
* But we had to alter page->flags anyway.
*
* Returns the number of pages moved to the given lru.
*/
static unsigned move_active_pages_to_lru(struct lruvec *lruvec,
struct list_head *list,
enum lru_list lru)
{
struct pglist_data *pgdat = lruvec_pgdat(lruvec);
LIST_HEAD(pages_to_free);
struct page *page;
int nr_pages;
int nr_moved = 0;
while (!list_empty(list)) {
page = lru_to_page(list);
lruvec = mem_cgroup_page_lruvec(page, pgdat);
VM_BUG_ON_PAGE(PageLRU(page), page);
SetPageLRU(page);
nr_pages = hpage_nr_pages(page);
update_lru_size(lruvec, lru, page_zonenum(page), nr_pages);
list_move(&page->lru, &lruvec->lists[lru]);
if (put_page_testzero(page)) {
__ClearPageLRU(page);
__ClearPageActive(page);
del_page_from_lru_list(page, lruvec, lru);
if (unlikely(PageCompound(page))) {
spin_unlock_irq(&pgdat->lru_lock);
mem_cgroup_uncharge(page);
(*get_compound_page_dtor(page))(page);
spin_lock_irq(&pgdat->lru_lock);
} else
list_add(&page->lru, &pages_to_free);
} else {
nr_moved += nr_pages;
}
}
/*
* To save our caller's stack, now use input list for pages to free.
*/
list_splice(&pages_to_free, list);
return nr_moved;
}
static void shrink_active_list(unsigned long nr_to_scan,
struct lruvec *lruvec,
struct scan_control *sc,
@ -2134,8 +2092,8 @@ static void shrink_active_list(unsigned long nr_to_scan,
*/
reclaim_stat->recent_rotated[file] += nr_rotated;
nr_activate = move_active_pages_to_lru(lruvec, &l_active, lru);
nr_deactivate = move_active_pages_to_lru(lruvec, &l_inactive, lru - LRU_ACTIVE);
nr_activate = move_pages_to_lru(lruvec, &l_active);
nr_deactivate = move_pages_to_lru(lruvec, &l_inactive);
/* Keep all free pages in l_active list */
list_splice(&l_inactive, &l_active);