diff options
author | Matthew Wilcox (Oracle) <willy@infradead.org> | 2023-10-04 19:53:02 +0300 |
---|---|---|
committer | Andrew Morton <akpm@linux-foundation.org> | 2023-10-19 00:34:16 +0300 |
commit | f45b494e2a24d86afd79cab7c343b414c5213447 (patch) | |
tree | 252790462ec5d8dd3cb181a59356cc0ae2d098cb | |
parent | 279d5fc3227f04ef2c6125e5c440e7952173a89a (diff) | |
download | linux-f45b494e2a24d86afd79cab7c343b414c5213447.tar.xz |
iomap: protect read_bytes_pending with the state_lock
Perform one atomic operation (acquiring the spinlock) instead of two
(spinlock & atomic_sub) per read completion.
Link: https://lkml.kernel.org/r/20231004165317.1061855-3-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>
-rw-r--r-- | fs/iomap/buffered-io.c | 37 |
1 files changed, 25 insertions, 12 deletions
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 6e780ca64ce3..4a996c5327ef 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -29,9 +29,9 @@ typedef int (*iomap_punch_t)(struct inode *inode, loff_t offset, loff_t length); * and I/O completions. */ struct iomap_folio_state { - atomic_t read_bytes_pending; - atomic_t write_bytes_pending; spinlock_t state_lock; + unsigned int read_bytes_pending; + atomic_t write_bytes_pending; /* * Each block has two bits in this bitmap: @@ -183,7 +183,7 @@ static void ifs_free(struct folio *folio) if (!ifs) return; - WARN_ON_ONCE(atomic_read(&ifs->read_bytes_pending)); + WARN_ON_ONCE(ifs->read_bytes_pending != 0); WARN_ON_ONCE(atomic_read(&ifs->write_bytes_pending)); WARN_ON_ONCE(ifs_is_fully_uptodate(folio, ifs) != folio_test_uptodate(folio)); @@ -250,19 +250,29 @@ static void iomap_adjust_read_range(struct inode *inode, struct folio *folio, *lenp = plen; } -static void iomap_finish_folio_read(struct folio *folio, size_t offset, +static void iomap_finish_folio_read(struct folio *folio, size_t off, size_t len, int error) { struct iomap_folio_state *ifs = folio->private; + bool uptodate = !error; + bool finished = true; - if (unlikely(error)) { - folio_clear_uptodate(folio); - folio_set_error(folio); - } else { - iomap_set_range_uptodate(folio, offset, len); + if (ifs) { + unsigned long flags; + + spin_lock_irqsave(&ifs->state_lock, flags); + if (!error) + uptodate = ifs_set_range_uptodate(folio, ifs, off, len); + ifs->read_bytes_pending -= len; + finished = !ifs->read_bytes_pending; + spin_unlock_irqrestore(&ifs->state_lock, flags); } - if (!ifs || atomic_sub_and_test(len, &ifs->read_bytes_pending)) + if (error) + folio_set_error(folio); + if (uptodate) + folio_mark_uptodate(folio); + if (finished) folio_unlock(folio); } @@ -360,8 +370,11 @@ static loff_t iomap_readpage_iter(const struct iomap_iter *iter, } ctx->cur_folio_in_bio = true; - if (ifs) - atomic_add(plen, &ifs->read_bytes_pending); + if (ifs) { + spin_lock_irq(&ifs->state_lock); + ifs->read_bytes_pending += plen; + spin_unlock_irq(&ifs->state_lock); + } sector = iomap_sector(iomap, pos); if (!ctx->bio || |