summaryrefslogtreecommitdiff
path: root/mm
diff options
context:
space:
mode:
authorMatthew Wilcox (Oracle) <willy@infradead.org>2023-10-04 17:53:17 +0100
committerAndrew Morton <akpm@linux-foundation.org>2023-10-18 14:34:17 -0700
commit2580d554585c52a644839864ef9238af5b030ebc (patch)
tree7577d911beacd7d8a2e17693bac5bdeb26b3e8f3 /mm
parent7d0795d098a127508f3e29ab4257c9ab598efaea (diff)
mm: use folio_xor_flags_has_waiters() in folio_end_writeback()
Match how folio_unlock() works by combining the test for PG_waiters with the clearing of PG_writeback. This should have a small performance win, and removes the last user of folio_wake(). Link: https://lkml.kernel.org/r/20231004165317.1061855-18-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexander Gordeev <agordeev@linux.ibm.com> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Christian Borntraeger <borntraeger@linux.ibm.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Henderson <richard.henderson@linaro.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r--mm/filemap.c15
-rw-r--r--mm/internal.h2
-rw-r--r--mm/page-writeback.c9
3 files changed, 10 insertions, 16 deletions
diff --git a/mm/filemap.c b/mm/filemap.c
index 523d9e15b3b0..b04ba896aac9 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1175,13 +1175,6 @@ static void folio_wake_bit(struct folio *folio, int bit_nr)
spin_unlock_irqrestore(&q->lock, flags);
}
-static void folio_wake(struct folio *folio, int bit)
-{
- if (!folio_test_waiters(folio))
- return;
- folio_wake_bit(folio, bit);
-}
-
/*
* A choice of three behaviors for folio_wait_bit_common():
*/
@@ -1618,13 +1611,11 @@ void folio_end_writeback(struct folio *folio)
* 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 folio is not freed and
- * reused before the folio_wake().
+ * reused before the folio_wake_bit().
*/
folio_get(folio);
- __folio_end_writeback(folio);
-
- smp_mb__after_atomic();
- folio_wake(folio, PG_writeback);
+ if (__folio_end_writeback(folio))
+ folio_wake_bit(folio, PG_writeback);
acct_reclaim_writeback(folio);
folio_put(folio);
}
diff --git a/mm/internal.h b/mm/internal.h
index ac4bbe2e2ca6..2b79da9deb64 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -105,7 +105,7 @@ static inline void wake_throttle_isolated(pg_data_t *pgdat)
vm_fault_t do_swap_page(struct vm_fault *vmf);
void folio_rotate_reclaimable(struct folio *folio);
-void __folio_end_writeback(struct folio *folio);
+bool __folio_end_writeback(struct folio *folio);
void deactivate_file_folio(struct folio *folio);
void folio_activate(struct folio *folio);
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index a37e4c33d1ab..46f2f5d3d183 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -2940,10 +2940,11 @@ static void wb_inode_writeback_end(struct bdi_writeback *wb)
spin_unlock_irqrestore(&wb->work_lock, flags);
}
-void __folio_end_writeback(struct folio *folio)
+bool __folio_end_writeback(struct folio *folio)
{
long nr = folio_nr_pages(folio);
struct address_space *mapping = folio_mapping(folio);
+ bool ret;
folio_memcg_lock(folio);
if (mapping && mapping_use_writeback_tags(mapping)) {
@@ -2952,7 +2953,7 @@ void __folio_end_writeback(struct folio *folio)
unsigned long flags;
xa_lock_irqsave(&mapping->i_pages, flags);
- folio_test_clear_writeback(folio);
+ ret = folio_xor_flags_has_waiters(folio, 1 << PG_writeback);
__xa_clear_mark(&mapping->i_pages, folio_index(folio),
PAGECACHE_TAG_WRITEBACK);
if (bdi->capabilities & BDI_CAP_WRITEBACK_ACCT) {
@@ -2970,13 +2971,15 @@ void __folio_end_writeback(struct folio *folio)
xa_unlock_irqrestore(&mapping->i_pages, flags);
} else {
- folio_test_clear_writeback(folio);
+ ret = folio_xor_flags_has_waiters(folio, 1 << PG_writeback);
}
lruvec_stat_mod_folio(folio, NR_WRITEBACK, -nr);
zone_stat_mod_folio(folio, NR_ZONE_WRITE_PENDING, -nr);
node_stat_mod_folio(folio, NR_WRITTEN, nr);
folio_memcg_unlock(folio);
+
+ return ret;
}
bool __folio_start_writeback(struct folio *folio, bool keep_write)