diff options
| author | Matthew Wilcox (Oracle) | 2023-10-04 17:53:07 +0100 |
|---|---|---|
| committer | Andrew Morton | 2023-10-18 14:34:16 -0700 |
| commit | 247dbcdbf790c52fc76cf8e327cd0a5778e41e66 (patch) | |
| tree | 6c11950be173d9cb443f7553eaebf3d7913062b7 /mm/kasan | |
| parent | 7a4847e54cc1889d109ce2a6ebed19aafc4a4af8 (diff) | |
bitops: add xor_unlock_is_negative_byte()
Replace clear_bit_and_unlock_is_negative_byte() with
xor_unlock_is_negative_byte(). We have a few places that like to lock a
folio, set a flag and unlock it again. Allow for the possibility of
combining the latter two operations for efficiency. We are guaranteed
that the caller holds the lock, so it is safe to unlock it with the xor.
The caller must guarantee that nobody else will set the flag without
holding the lock; it is not safe to do this with the PG_dirty flag, for
example.
Link: https://lkml.kernel.org/r/20231004165317.1061855-8-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/kasan')
| -rw-r--r-- | mm/kasan/kasan_test.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/mm/kasan/kasan_test.c b/mm/kasan/kasan_test.c index 2030c7ff7de9..821c9ea0473a 100644 --- a/mm/kasan/kasan_test.c +++ b/mm/kasan/kasan_test.c @@ -1099,9 +1099,10 @@ static void kasan_bitops_test_and_modify(struct kunit *test, int nr, void *addr) KUNIT_EXPECT_KASAN_FAIL(test, __test_and_change_bit(nr, addr)); KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = test_bit(nr, addr)); -#if defined(clear_bit_unlock_is_negative_byte) - KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = - clear_bit_unlock_is_negative_byte(nr, addr)); +#if defined(xor_unlock_is_negative_byte) + if (nr < 7) + KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = + xor_unlock_is_negative_byte(1 << nr, addr)); #endif } |