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author | Yan, Zheng <zyan@redhat.com> | 2019-02-01 14:57:15 +0800 |
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committer | Ilya Dryomov <idryomov@gmail.com> | 2019-03-05 18:55:17 +0100 |
commit | fe33032daae2e584d9e7e33bab44c9eafced1f8f (patch) | |
tree | a03be95fd94ffcd66c69e2146a1930837f769eb4 /fs/ceph/dir.c | |
parent | 37c4efc1ddf98ba8b234d116d863a9464445901e (diff) | |
download | lwn-fe33032daae2e584d9e7e33bab44c9eafced1f8f.tar.gz lwn-fe33032daae2e584d9e7e33bab44c9eafced1f8f.zip |
ceph: add mount option to limit caps count
If number of caps exceed the limit, ceph_trim_dentires() also trim
dentries with valid leases. Trimming dentry releases references to
associated inode, which may evict inode and release caps.
By default, there is no limit for caps count.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Diffstat (limited to 'fs/ceph/dir.c')
-rw-r--r-- | fs/ceph/dir.c | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c index eba283557653..a8f429882249 100644 --- a/fs/ceph/dir.c +++ b/fs/ceph/dir.c @@ -1224,6 +1224,7 @@ enum { struct ceph_lease_walk_control { bool dir_lease; + bool expire_dir_lease; unsigned long nr_to_scan; unsigned long dir_lease_ttl; }; @@ -1345,7 +1346,13 @@ static int __dir_lease_check(struct dentry *dentry, void *arg) /* Move dentry to tail of dir lease list if we don't want * to delete it. So dentries in the list are checked in a * round robin manner */ - return TOUCH; + if (!lwc->expire_dir_lease) + return TOUCH; + if (dentry->d_lockref.count > 0 || + (di->flags & CEPH_DENTRY_REFERENCED)) + return TOUCH; + /* invalidate dir lease */ + di->lease_shared_gen = 0; } return DELETE; } @@ -1353,8 +1360,17 @@ static int __dir_lease_check(struct dentry *dentry, void *arg) int ceph_trim_dentries(struct ceph_mds_client *mdsc) { struct ceph_lease_walk_control lwc; + unsigned long count; unsigned long freed; + spin_lock(&mdsc->caps_list_lock); + if (mdsc->caps_use_max > 0 && + mdsc->caps_use_count > mdsc->caps_use_max) + count = mdsc->caps_use_count - mdsc->caps_use_max; + else + count = 0; + spin_unlock(&mdsc->caps_list_lock); + lwc.dir_lease = false; lwc.nr_to_scan = CEPH_CAPS_PER_RELEASE * 2; freed = __dentry_leases_walk(mdsc, &lwc, __dentry_lease_check); @@ -1365,6 +1381,8 @@ int ceph_trim_dentries(struct ceph_mds_client *mdsc) lwc.nr_to_scan = CEPH_CAPS_PER_RELEASE; lwc.dir_lease = true; + lwc.expire_dir_lease = freed < count; + lwc.dir_lease_ttl = mdsc->fsc->mount_options->caps_wanted_delay_max * HZ; freed +=__dentry_leases_walk(mdsc, &lwc, __dir_lease_check); if (!lwc.nr_to_scan) /* more to check */ return -EAGAIN; |