diff options
| -rw-r--r-- | drivers/parport/parport_pc.c | 3 | ||||
| -rw-r--r-- | fs/buffer.c | 15 |
2 files changed, 15 insertions, 3 deletions
diff --git a/drivers/parport/parport_pc.c b/drivers/parport/parport_pc.c index d76d37bcb9c..a8580893820 100644 --- a/drivers/parport/parport_pc.c +++ b/drivers/parport/parport_pc.c @@ -1568,9 +1568,8 @@ static void __devinit detect_and_report_it87(void) outb(r | 8, 0x2F); outb(0x02, 0x2E); /* Lock */ outb(0x02, 0x2F); - - release_region(0x2e, 1); } + release_region(0x2e, 1); } #endif /* CONFIG_PARPORT_PC_SUPERIO */ diff --git a/fs/buffer.c b/fs/buffer.c index 98196327ddf..39ff14403d1 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -1181,7 +1181,20 @@ __getblk_slow(struct block_device *bdev, sector_t block, int size) void mark_buffer_dirty(struct buffer_head *bh) { WARN_ON_ONCE(!buffer_uptodate(bh)); - if (!buffer_dirty(bh) && !test_set_buffer_dirty(bh)) + + /* + * Very *carefully* optimize the it-is-already-dirty case. + * + * Don't let the final "is it dirty" escape to before we + * perhaps modified the buffer. + */ + if (buffer_dirty(bh)) { + smp_mb(); + if (buffer_dirty(bh)) + return; + } + + if (!test_set_buffer_dirty(bh)) __set_page_dirty(bh->b_page, page_mapping(bh->b_page), 0); } |