| Message ID | 20231007153956.344794-1-shikemeng@huaweicloud.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] fuse: remove unneeded lock which protecting update of congestion_threshold | expand |
On Sat, 7 Oct 2023 at 09:40, Kemeng Shi <shikemeng@huaweicloud.com> wrote: > > Commit 670d21c6e17f6 ("fuse: remove reliance on bdi congestion") change how > congestion_threshold is used and lock in > fuse_conn_congestion_threshold_write is not needed anymore. > 1. Access to supe_block is removed along with removing of bdi congestion. > Then down_read(&fc->killsb) which protecting access to super_block is no > needed. > 2. Compare num_background and congestion_threshold without holding > bg_lock. Then there is no need to hold bg_lock to update > congestion_threshold. > > Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> Applied, thanks. Miklos
diff --git a/fs/fuse/control.c b/fs/fuse/control.c index ab62e4624256..1bf928e277fe 100644 --- a/fs/fuse/control.c +++ b/fs/fuse/control.c @@ -174,11 +174,7 @@ static ssize_t fuse_conn_congestion_threshold_write(struct file *file, if (!fc) goto out; - down_read(&fc->killsb); - spin_lock(&fc->bg_lock); - fc->congestion_threshold = val; - spin_unlock(&fc->bg_lock); - up_read(&fc->killsb); + WRITE_ONCE(fc->congestion_threshold, val); fuse_conn_put(fc); out: return ret;
Commit 670d21c6e17f6 ("fuse: remove reliance on bdi congestion") change how congestion_threshold is used and lock in fuse_conn_congestion_threshold_write is not needed anymore. 1. Access to supe_block is removed along with removing of bdi congestion. Then down_read(&fc->killsb) which protecting access to super_block is no needed. 2. Compare num_background and congestion_threshold without holding bg_lock. Then there is no need to hold bg_lock to update congestion_threshold. Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com> --- fs/fuse/control.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)