mm/filemap: Add folio_end_writeback()

Add an end_page_writeback() wrapper function for users that are not yet
converted to folios.

folio_end_writeback() is less than half the size of end_page_writeback()
at just 105 bytes compared to 228 bytes, due to removing all the
compound_head() calls.  The 30 byte wrapper function makes this a net
saving of 93 bytes.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
This commit is contained in:
Matthew Wilcox (Oracle) 2021-03-03 15:21:55 -05:00
parent 575ced1c8b
commit 4268b48077
3 changed files with 29 additions and 23 deletions

View File

@ -767,7 +767,8 @@ static inline int wait_on_page_locked_killable(struct page *page)
int put_and_wait_on_page_locked(struct page *page, int state);
void wait_on_page_writeback(struct page *page);
int wait_on_page_writeback_killable(struct page *page);
extern void end_page_writeback(struct page *page);
void end_page_writeback(struct page *page);
void folio_end_writeback(struct folio *folio);
void wait_for_stable_page(struct page *page);
void __set_page_dirty(struct page *, struct address_space *, int warn);

View File

@ -1230,11 +1230,11 @@ static void wake_up_page_bit(struct page *page, int bit_nr)
spin_unlock_irqrestore(&q->lock, flags);
}
static void wake_up_page(struct page *page, int bit)
static void folio_wake(struct folio *folio, int bit)
{
if (!PageWaiters(page))
if (!folio_test_waiters(folio))
return;
wake_up_page_bit(page, bit);
wake_up_page_bit(&folio->page, bit);
}
/*
@ -1571,39 +1571,38 @@ int wait_on_page_private_2_killable(struct page *page)
EXPORT_SYMBOL(wait_on_page_private_2_killable);
/**
* end_page_writeback - end writeback against a page
* @page: the page
* folio_end_writeback - End writeback against a folio.
* @folio: The folio.
*/
void end_page_writeback(struct page *page)
void folio_end_writeback(struct folio *folio)
{
/*
* TestClearPageReclaim could be used here but it is an atomic
* operation and overkill in this particular case. Failing to
* shuffle a page marked for immediate reclaim is too mild to
* justify taking an atomic operation penalty at the end of
* ever page writeback.
* folio_test_clear_reclaim() could be used here but it is an
* atomic operation and overkill in this particular case. Failing
* to shuffle a folio marked for immediate reclaim is too mild
* a gain to justify taking an atomic operation penalty at the
* end of every folio writeback.
*/
if (PageReclaim(page)) {
struct folio *folio = page_folio(page);
ClearPageReclaim(page);
if (folio_test_reclaim(folio)) {
folio_clear_reclaim(folio);
folio_rotate_reclaimable(folio);
}
/*
* Writeback does not hold a page reference of its own, relying
* Writeback does not hold a folio reference of its own, relying
* on truncation to wait for the clearing of PG_writeback.
* But here we must make sure that the page is not freed and
* reused before the wake_up_page().
* But here we must make sure that the folio is not freed and
* reused before the folio_wake().
*/
get_page(page);
if (!test_clear_page_writeback(page))
folio_get(folio);
if (!test_clear_page_writeback(&folio->page))
BUG();
smp_mb__after_atomic();
wake_up_page(page, PG_writeback);
put_page(page);
folio_wake(folio, PG_writeback);
folio_put(folio);
}
EXPORT_SYMBOL(end_page_writeback);
EXPORT_SYMBOL(folio_end_writeback);
/*
* After completing I/O on a page, call this routine to update the page

View File

@ -17,3 +17,9 @@ void unlock_page(struct page *page)
return folio_unlock(page_folio(page));
}
EXPORT_SYMBOL(unlock_page);
void end_page_writeback(struct page *page)
{
return folio_end_writeback(page_folio(page));
}
EXPORT_SYMBOL(end_page_writeback);