This is a note to let you know that I've just added the patch titled ceph: fix duplicate increment of opened_inodes metric to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ceph-fix-duplicate-increment-of-opened_inodes-metric.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 77339a6a9a6f5f8e10c4bcf8c6f2df3d63837a7c Author: Hu Weiwen <sehuww@xxxxxxxxxxxxxxxx> Date: Mon Nov 22 22:22:12 2021 +0800 ceph: fix duplicate increment of opened_inodes metric [ Upstream commit 973e5245637accc4002843f6b888495a6a7762bc ] opened_inodes is incremented twice when the same inode is opened twice with O_RDONLY and O_WRONLY respectively. To reproduce, run this python script, then check the metrics: import os for _ in range(10000): fd_r = os.open('a', os.O_RDONLY) fd_w = os.open('a', os.O_WRONLY) os.close(fd_r) os.close(fd_w) Fixes: 1dd8d4708136 ("ceph: metrics for opened files, pinned caps and opened inodes") Signed-off-by: Hu Weiwen <sehuww@xxxxxxxxxxxxxxxx> Reviewed-by: Xiubo Li <xiubli@xxxxxxxxxx> Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 676f551953060..d3f67271d3c72 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -4359,7 +4359,7 @@ void ceph_get_fmode(struct ceph_inode_info *ci, int fmode, int count) { struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(ci->vfs_inode.i_sb); int bits = (fmode << 1) | 1; - bool is_opened = false; + bool already_opened = false; int i; if (count == 1) @@ -4367,19 +4367,19 @@ void ceph_get_fmode(struct ceph_inode_info *ci, int fmode, int count) spin_lock(&ci->i_ceph_lock); for (i = 0; i < CEPH_FILE_MODE_BITS; i++) { - if (bits & (1 << i)) - ci->i_nr_by_mode[i] += count; - /* - * If any of the mode ref is larger than 1, + * If any of the mode ref is larger than 0, * that means it has been already opened by * others. Just skip checking the PIN ref. */ - if (i && ci->i_nr_by_mode[i] > 1) - is_opened = true; + if (i && ci->i_nr_by_mode[i]) + already_opened = true; + + if (bits & (1 << i)) + ci->i_nr_by_mode[i] += count; } - if (!is_opened) + if (!already_opened) percpu_counter_inc(&mdsc->metric.opened_inodes); spin_unlock(&ci->i_ceph_lock); }