[PATCH 03/11] nfs: use clear_and_wake_up_bit().

NeilBrown
2024-12-06T02:19:21Z

In three places nfs clears a bit and then sends a wake_up_bit().
Using clear_and_wake_up_bit() makes this code cleaner and avoids the
need for explicit barriers.

In 2 cases the wake_up is conditional on a "congested" flag. For these
we use the flag to select between clear_bit and clear_and_wake_up_bit.

Signed-off-by: NeilBrown <neilb@suse.de>
---
fs/nfs/inode.c | 4 +---
fs/nfs/pagelist.c | 14 ++++++--------
2 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 596f35170137..4c4c3ab57fcd 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1451,9 +1451,7 @@ int nfs_clear_invalid_mapping(struct address_space *mapping)
ret = nfs_invalidate_mapping(inode, mapping);
trace_nfs_invalidate_mapping_exit(inode, ret);

- clear_bit_unlock(NFS_INO_INVALIDATING, bitlock);
- smp_mb__after_atomic();
- wake_up_bit(bitlock, NFS_INO_INVALIDATING);
+ clear_and_wake_up_bit(NFS_INO_INVALIDATING, bitlock);
out:
return ret;
}
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index e27c07bd8929..7f3914064cee 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -214,11 +214,10 @@ nfs_page_set_headlock(struct nfs_page *req)
void
nfs_page_clear_headlock(struct nfs_page *req)
{
- clear_bit_unlock(PG_HEADLOCK, &req->wb_flags);
- smp_mb__after_atomic();
if (!test_bit(PG_CONTENDED1, &req->wb_flags))
- return;
- wake_up_bit(&req->wb_flags, PG_HEADLOCK);
+ clear_bit_unlock(PG_HEADLOCK, &req->wb_flags);
+ else
+ clear_and_wake_up_bit(PG_HEADLOCK, &req->wb_flags);
}

/*
@@ -519,11 +518,10 @@ nfs_create_subreq(struct nfs_page *req,
*/
void nfs_unlock_request(struct nfs_page *req)
{
- clear_bit_unlock(PG_BUSY, &req->wb_flags);
- smp_mb__after_atomic();
if (!test_bit(PG_CONTENDED2, &req->wb_flags))
- return;
- wake_up_bit(&req->wb_flags, PG_BUSY);
+ clear_bit_unlock(PG_BUSY, &req->wb_flags);
+ else
+ clear_and_wake_up_bit(PG_BUSY, &req->wb_flags);
}

/**
--
2.47.0