fscache: Use clear_and_wake_up_bit() in fscache_create_volume_work()
authorHou Tao <houtao1@huawei.com>
Fri, 13 Jan 2023 11:52:11 +0000 (19:52 +0800)
committerDavid Howells <dhowells@redhat.com>
Mon, 30 Jan 2023 12:51:54 +0000 (12:51 +0000)
commit3288666c72568fe1cc7f5c5ae33dfd3ab18004c8
treebe3af6c5f73e396fe2786fd7c1359bdc9a161f41
parent8226e37d82f43657da34dd770e2b38f20242ada7
fscache: Use clear_and_wake_up_bit() in fscache_create_volume_work()

fscache_create_volume_work() uses wake_up_bit() to wake up the processes
which are waiting for the completion of volume creation. According to
comments in wake_up_bit() and waitqueue_active(), an extra smp_mb() is
needed to guarantee the memory order between FSCACHE_VOLUME_CREATING
flag and waitqueue_active() before invoking wake_up_bit().

Fixing it by using clear_and_wake_up_bit() to add the missing memory
barrier.

Reviewed-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20230113115211.2895845-3-houtao@huaweicloud.com/
fs/fscache/volume.c